The "CO2 is Plant Food" Crock

Of course Tim Curtin's response here(# 19) should IMHO be deleted. His arguments were ripped apart on his own thread, and then he has the gall to pop up here, with more ridiculous claims and accusations of a contributor's arguments making him akin to the fraudster Bernie Madoff. How childish.

Curtin has published his frankly silly stuff (at least that is how I interpret it) in the non-ISI WOS listed contrarian journal, E & E (I suppose he knew it would not stand a change of being published in a more rigid journal as the many flaws would have been pointed out by the referees, followed by a swift rejection).

As I said before, anyone interested in the systematic demolition of a contrarian's views ought to visit the Tim Curtin thread.

Adelady (August 19, 2010 8:58 AM): you said

"frank. Photosynthesis isn't the only effect of CO2 on a plant's growing environment.

http://www.sciencedaily.com/releases/2010/08/100809161138.htm

Not so encouraging."

Drivel, even by your standards, adewoman.

That ScienceDaily report merely parrots without acknowledgment the IRRI media release on the Welch et al paper. Even the BBC was forced by Anthony Watts to retract its own parroting of Welch/IRRI with their ludicrous claim that ABSOLUTE rice yields had declined, rather than merely, allegedly, the rate of growth of such yields, which is what the paper actually claimed.

adewoman: the Welch paper specifically assumes ZERO CO2 fertilization, exactly what we have come to expect from the so-called National Academy of Science (aka Walt Disney Studios).

And dear adewoman (how can we meet?), if you had any shred of competence you, unlike Welch and co who do not have any, would check the FAO data base on rice yields from 1990 to 1999 in the countries covered by Welch & co, against the yields from 1990 to 2008 inclusive.

Dear addie, the FAO data shows that while Welch et al claimed their data for six countries from c.1994 to 1999 was enough to project declining rice yields worldwide for ever after from 1999, here are the actual linear trends for changes (GROWTH or DECLINE) in growth of yields in their six countries from 1990 to 2008:

China: y = -0.0526x + 1.4725
R² = 0.0222

India: y = 0.1092x + 0.4847
R² = 0.0075

Indonesia: y = 0.0992x - 0.2249
R² = 0.0868

Philippines: y = 0.0772x + 1.0813
R² = 0.0099

Thailand: y = -0.0265x + 2.2615
R² = 0.0009

Vietnam: y = 0.0469x + 2.1476
R² = 0.0117

Now they projected the following DECLINES in absolute yields for those countries (in % p.a.):

China (high): 0
China (low): - 0.07
China (actual, 2nd d, 1990-2008):y = -0.0526x + 1.4725

India (high): -.04
India (low): - .07
India (actual, 2nd d, 1990-2008):y = 0.1092x + 0.4847

Indonesia (high): 0.22
Indonesia (low): 0.17
Indonesia (actual, 2nd d, 1990-2008): y = 0.0992x - 0.2249

Philippines (high): 0.31
Philippines (low): 0.32
Philippines (actual, 2nd d, 1990-2008):y = 0.0772x + 1.0813

Thailand (high): 0.23
Thailand (low): -0.35
Thailand (actual, 2nd d, 1990-2008):y = -0.0265x + 2.2615

Vietnam (Hanoi, high): 0.38; (Omon, high): -0.33
Vietnam (Hanoi, low): -0.22; (Omon, low): -0.76
Vietnam (actual, 2nd d, national):y = 0.0469x + 2.1476

Dear addled: if you think the actual trends in rice yield GROWTH rates support the claim in the IRRI/ScienceDaily/BBC that ââas the daily minimum temperature increases, or as nights get hotter, rice yields drop,â said Mr. Jarrod Welch, lead author of the reportâ, all plans for us to meet are off!

Tim Curtin:

> I realise Tim Lambert will delete this Reply to Adelady (at #10) as soon as he sees it here, so I will also post this at the one thread here where I am allowed to exercise some free speech.

this is a private blog. what makes you think you have some God-given right to free speech?

[bet this doesn't get published!!!!!](http://ifyoulikeitsomuchwhydontyougolivethere.com/2008/09/10/abuse-publ…)

Someone notify Tim Lambert, Dim Curtain's out of his cell.

Hi Tim, with your renowned sense of fair play here is my response to those whom you still allow to attack me without so far allowing me any right of reply to comments like this:

Wow!

No, no, no, nooooo!

I was trying to see if I could get a straight answer out of Cohenite and Tim Curtain. I will will win a lot of money if I don't.

Posted by: Jeremy C | August 20, 2010 9:45 AM

Then we have Adelady (August 19, 2010 8:58 AM) who said

"frank. Photosynthesis isn't the only effect of CO2 on a plant's growing environment.

http://www.sciencedaily.com/releases/2010/08/100809161138.htm

Not so encouraging."

The link is to a media release from IRRI (near Manila) announcing the paper by Welch et al that appeared in PNAS on 9th August and referred to here by P Lewis for allegedly refuting any role of [CO2] in rice yields.

Drivel, even by your standards, adewoman.

That ScienceDaily report merely parrots without acknowledgment the IRRI media release on the Welch et al paper. Even the BBC was forced by Anthony Watts to retract its own parroting of Welch/IRRI with their ludicrous claim that ABSOLUTE rice yields had declined, rather than merely, allegedly, the rate of growth of such yields, which is what the paper actually claimed.

adewoman: the Welch paper specifically assumes ZERO CO2 fertilization, exactly what we have come to expect from the so-called National Academy of Science (aka Walt Disney Studios).

And dear adewoman (how can we meet?), if you had any shred of competence you, unlike Welch and co who do not have any, would check the FAO data base on rice yields from 1990 to 1999 in the countries covered by Welch & co, against the yields from 1990 to 2008 inclusive.

Dear addie, the FAO data shows that while Welch et al claimed their data for six countries from c.1994 to 1999 was enough to project declining rice yields worldwide for ever after from 1999, here are the actual linear trends for changes (GROWTH or DECLINE) in growth of yields in their six countries from 1990 to 2008:

China: y = -0.0526x + 1.4725
R² = 0.0222

India: y = 0.1092x + 0.4847
R² = 0.0075

Indonesia: y = 0.0992x - 0.2249
R² = 0.0868

Philippines: y = 0.0772x + 1.0813
R² = 0.0099

Thailand: y = -0.0265x + 2.2615
R² = 0.0009

Vietnam: y = 0.0469x + 2.1476
R² = 0.0117

Now they projected the following DECLINES in absolute yields for those countries (in % p.a.):

China (high): 0
China (low): - 0.07
China (actual, 2nd d, 1990-2008):y = -0.0526x + 1.4725

India (high): -.04
India (low): - .07
India (actual, 2nd d, 1990-2008):y = 0.1092x + 0.4847

Indonesia (high): 0.22
Indonesia (low): 0.17
Indonesia (actual, 2nd d, 1990-2008): y = 0.0992x - 0.2249

Philippines (high): 0.31
Philippines (low): 0.32
Philippines (actual, 2nd d, 1990-2008):y = 0.0772x + 1.0813

Thailand (high): 0.23
Thailand (low): -0.35
Thailand (actual, 2nd d, 1990-2008):y = -0.0265x + 2.2615

Vietnam (Hanoi, high): 0.38; (Omon, high): -0.33
Vietnam (Hanoi, low): -0.22; (Omon, low): -0.76
Vietnam (actual, 2nd d, national):y = 0.0469x + 2.1476

Dear addled: if you think the actual trends in rice yield growth rates support the claim in the IRRI/ScienceDaily/BBC that ââas the daily minimum temperature increases, or as nights get hotter, rice yields drop,â said Mr. Jarrod Welch, lead author of the reportâ, all plans for us to meet are off!

Adelady (August 19, 2010 8:58 AM): you said

"frank. Photosynthesis isn't the only effect of CO2 on a plant's growing environment.

http://www.sciencedaily.com/releases/2010/08/100809161138.htm

Not so encouraging."

Drivel, even by your standards, adewoman.

That ScienceDaily report merely parrots without acknowledgment the IRRI media release on the Welch et al paper. Even the BBC was forced by Anthony Watts to retract its own parroting of Welch/IRRI with their ludicrous claim that ABSOLUTE rice yields had declined, rather than merely, allegedly, the rate of growth of such yields, which is what the paper actually claimed.

adewoman: the Welch paper specifically assumes ZERO CO2 fertilization, exactly what we have come to expect from the so-called National Academy of Science (aka Walt Disney Studios).

And dear adewoman (how can we meet?) if you had any shred of competence you, unlike Welch and co who do not have any, would check the FAO data base on rice yields from 1990 to 1999 in the countries covered by Welch & co, against the yields from 2000 to 2008 inclusive.

Dear addie, the FAO data shows that while Welch et al claimed their data for six countries from c.1994 to 1999 was enough to project declining rice yields worldwide for ever after from 1999, here are the actual linear trends for their six countries from 1990 to 2008:

China: y = -0.0526x + 1.4725
R² = 0.0222

India: y = 0.1092x + 0.4847
R² = 0.0075

Indonesia: y = 0.0992x - 0.2249
R² = 0.0868

Philippines: y = 0.0772x + 1.0813
R² = 0.0099

Thailand: y = -0.0265x + 2.2615
R² = 0.0009

Vietnam: y = 0.0469x + 2.1476
R² = 0.0117

Now they projected the following DECLINES in yields for those countries (in % p.a.):

China (high): 0
China (low): - 0.07
China (actual, 2nd d, 1990-2008):y = -0.0526x + 1.4725

India (high): -.04
India (low): - .07
India (actual, 2nd d, 1990-2008):y = 0.1092x + 0.4847

Indonesia (high): 0.22
Indonesia (low): 0.17
Indonesia (actual, 2nd d, 1990-2008): y = 0.0992x - 0.2249

Philippines (high): 0.31
Philippines (low): 0.32
Philippines (actual, 2nd d, 1990-2008):y = 0.0772x + 1.0813

Thailand (high): 0.23
Thailand (low): -0.35
Thailand (actual, 2nd d, 1990-2008):y = -0.0265x + 2.2615

Vietnam (Hanoi, high): 0.38; (Omon, high): -0.33
Vietnam (Hanoi, low): -0.22; (Omon, low): -0.76
Vietnam (actual, 2nd d, national):y = 0.0469x + 2.1476
Dear addled: if you think the actual trends in rice yields support the claim in the IRRI/ScienceDaily/BBC that ââas the daily minimum temperature increases, or as nights get hotter, rice yields drop,â said Mr. Jarrod Welch, lead author of the reportâ, all plans for us to meet are off!

Adelady (August 19, 2010 8:58 AM): you said

"frank. Photosynthesis isn't the only effect of CO2 on a plant's growing environment.

http://www.sciencedaily.com/releases/2010/08/100809161138.htm

Not so encouraging."

The link is to a media release from IRRI (near Manila) announcing the paper by Welch et al that appeared in PNAS on 9th August and referred to here by P Lewis for allegedly refuting any role of [CO2] in rice yields.

Drivel, even by your standards, adewoman.

That ScienceDaily report merely parrots without acknowledgment the IRRI media release on the Welch et al paper. Even the BBC was forced by Anthony Watts to retract its own parroting of Welch/IRRI with their ludicrous claim that ABSOLUTE rice yields had declined, rather than merely, allegedly, the rate of growth of such yields, which is what the paper actually claimed.

adewoman: the Welch paper specifically assumes ZERO CO2 fertilization, exactly what we have come to expect from the so-called National Academy of Science (aka Walt Disney Studios).

And dear adewoman (how can we meet?), if you had any shred of competence you, unlike Welch and co who do not have any, would check the FAO data base on rice yields from 1990 to 1999 in the countries covered by Welch & co, against the yields from 1990 to 2008 inclusive.

Dear addie, the FAO data shows that while Welch et al claimed their data for six countries from c.1994 to 1999 was enough to project declining rice yields worldwide for ever after from 1999, here are the actual linear trends for changes (GROWTH or DECLINE) in growth of yields in their six countries from 1990 to 2008:

China: y = -0.0526x + 1.4725
R² = 0.0222

India: y = 0.1092x + 0.4847
R² = 0.0075

Indonesia: y = 0.0992x - 0.2249
R² = 0.0868

Philippines: y = 0.0772x + 1.0813
R² = 0.0099

Thailand: y = -0.0265x + 2.2615
R² = 0.0009

Vietnam: y = 0.0469x + 2.1476
R² = 0.0117

Now they projected the following DECLINES in absolute yields for those countries (in % p.a.):

China (high): 0
China (low): - 0.07
China (actual, 2nd d, 1990-2008):y = -0.0526x + 1.4725

India (high): -.04
India (low): - .07
India (actual, 2nd d, 1990-2008):y = 0.1092x + 0.4847

Indonesia (high): 0.22
Indonesia (low): 0.17
Indonesia (actual, 2nd d, 1990-2008): y = 0.0992x - 0.2249

Philippines (high): 0.31
Philippines (low): 0.32
Philippines (actual, 2nd d, 1990-2008):y = 0.0772x + 1.0813

Thailand (high): 0.23
Thailand (low): -0.35
Thailand (actual, 2nd d, 1990-2008):y = -0.0265x + 2.2615

Vietnam (Hanoi, high): 0.38; (Omon, high): -0.33
Vietnam (Hanoi, low): -0.22; (Omon, low): -0.76
Vietnam (actual, 2nd d, national):y = 0.0469x + 2.1476

Dear addled: if you think the actual trends in rice yield growth rates support the claim in the IRRI/ScienceDaily/BBC that ââas the daily minimum temperature increases, or as nights get hotter, rice yields drop,â said Mr. Jarrod Welch, lead author of the reportâ, all plans for us to meet are off!

Adelady (August 19, 2010 8:58 AM): you said

"frank. Photosynthesis isn't the only effect of CO2 on a plant's growing environment.

http://www.sciencedaily.com/releases/2010/08/100809161138.htm

Not so encouraging."

Drivel, even by your standards, adewoman.

That ScienceDaily report merely parrots without acknowledgment the IRRI media release on the Welch et al paper. Even the BBC was forced by Anthony Watts to retract its own parroting of Welch/IRRI with their ludicrous claim that ABSOLUTE rice yields had declined, rather than merely, allegedly, the rate of growth of such yields, which is what the paper actually claimed.

adewoman: the Welch paper specifically assumes ZERO CO2 fertilization, exactly what we have come to expect from the so-called National Academy of Science (aka Walt Disney Studios).

And dear adewoman (how can we meet?) if you had any shred of competence you, unlike Welch and co who do not have any, would check the FAO data base on rice yields from 1990 to 1999 in the countries covered by Welch & co, against the yields from 2000 to 2008 inclusive.

Dear addie, the FAO data shows that while Welch et al claimed their data for six countries from c.1994 to 1999 was enough to project declining rice yields worldwide for ever after from 1999, here are the actual linear trends for their six countries from 1990 to 2008:

China: y = -0.0526x + 1.4725
R² = 0.0222

India: y = 0.1092x + 0.4847
R² = 0.0075

Indonesia: y = 0.0992x - 0.2249
R² = 0.0868

Philippines: y = 0.0772x + 1.0813
R² = 0.0099

Thailand: y = -0.0265x + 2.2615
R² = 0.0009

Vietnam: y = 0.0469x + 2.1476
R² = 0.0117

Now they projected the following DECLINES in yields for those countries (in % p.a.):

China (high): 0
China (low): - 0.07
China (actual, 2nd d, 1990-2008):y = -0.0526x + 1.4725

India (high): -.04
India (low): - .07
India (actual, 2nd d, 1990-2008):y = 0.1092x + 0.4847

Indonesia (high): 0.22
Indonesia (low): 0.17
Indonesia (actual, 2nd d, 1990-2008): y = 0.0992x - 0.2249

Philippines (high): 0.31
Philippines (low): 0.32
Philippines (actual, 2nd d, 1990-2008):y = 0.0772x + 1.0813

Thailand (high): 0.23
Thailand (low): -0.35
Thailand (actual, 2nd d, 1990-2008):y = -0.0265x + 2.2615

Vietnam (Hanoi, high): 0.38; (Omon, high): -0.33
Vietnam (Hanoi, low): -0.22; (Omon, low): -0.76
Vietnam (actual, 2nd d, national):y = 0.0469x + 2.1476
Dear addled: if you think the actual trends in rice yields support the claim in the IRRI/ScienceDaily/BBC that ââas the daily minimum temperature increases, or as nights get hotter, rice yields drop,â said Mr. Jarrod Welch, lead author of the reportâ, all plans for us to meet are off!

Paddy,

Are you really defending the man who said that, if ocean acidification was really happenning, it would not be a worry because we'd then [be able to use the sea for drinking and irrigation?](http://scienceblogs.com/deltoid/2010/04/tim_curtin_thread_now_a_live_s…)

Bernard [helpfully gives us a summary](http://scienceblogs.com/deltoid/2010/04/tim_curtin_thread_now_a_live_s…) of the increasing surreality of TC's arguments on that subject...

Then he says that the fraction of our emitted CO2 that does not end up in the atmosphere [goes exclusively to bolster food production](http://scienceblogs.com/deltoid/2010/04/tim_curtin_thread_now_a_live_s…)...

His entire criticism of the MAGICC model, which underpins a lot of his argument that the IPCC is wrong, was based on using [the wrong equation](http://scienceblogs.com/deltoid/2010/04/tim_curtin_thread_now_a_live_s…) from a paper he did not understand...

A man who comments on the scientific merit of papers based on what somebody else had to say about them, [not having read them](http://scienceblogs.com/deltoid/2010/04/tim_curtin_thread_now_a_live_s…)...

And then calls a paper nothing but a tissue of l!es from beginning to end, making [all sorts of absurd claims](http://scienceblogs.com/deltoid/2010/04/tim_curtin_thread_now_a_live_s…) and misrepresenting the authors in ways that have not even yet been invented... As of the end of his thread, he never answered about how he could [justify his l!es](http://scienceblogs.com/deltoid/2010/04/tim_curtin_thread_now_a_live_s…), especially [this one](http://scienceblogs.com/deltoid/2010/04/tim_curtin_thread_now_a_live_s…).

Ah, Paddy, but why does that not surprise me, coming from a person with an intellectual age so low as to publish [this comment](http://scienceblogs.com/deltoid/2010/04/tim_curtin_thread_now_a_live_s…) on a scientific blog:
>Jeff, I looked you up, I'm very impressed and luved the photo of you collecting seal semen, I coming to Holland soon, would you like to hook up ?

Jeff Harvey,
"Theoretical models correalting C02 with NPP are only as good or accurate as the parameters that are fitted into them."

Oh Jeff, do you not realise that exactly the same is true about the parameters fitted into GCMs?

Come on guys. Where is the link between anthropogenic CO2 and 'global warming' ? It still has not been detected.

[Hans](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

There is nothing "incorrect" about [my last post on this thread](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

Several more degrees of global warming will have significant effects both on the biosphere in general, and on human societies as a matter of relevance to ourselves and to our decendants.

This is simple, inescapable fact. Talk to a scientist some time to find out why.

That [the poster "J" does not understand this](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…), and that you do not seem to have understood my point either, is no fault of mine. There is certainly no basis for [one anonymous idiot](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…), supported by another [anonymous nincompoop](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…), to be threatening Tim Lambert with a subpÅna in order to determine the identity of a semi-anonymous poster on a blog, such as I am.

If I could understand your garbled comment better than I am able to, I would address your points specifically. As it stands though, you present no coherent argument, and you are really just pissing on your own shoes.

Congratulations for doing your part to [shift "B" even further toward 0](http://i34.tinypic.com/etv66q.jpg).

Tim,

Why do you allow people like Wow,
Stu and Chek to make asinine comments about someone's lack of English when that person has already apologised for it in advance?

If I were to stereotype I would say this is typical Oz chauvinist behaviour.

Tim

My ban has lasted one year!

When is it going to end?

Girma

Tim,

What a nice safe blog you can now have.

Endless repetitions of Jeff Harvey telling you why he is such a great scientist with understanding of everything in the political world even though he has never set foot outside academe.

Lots of yes people to agree with you.

No need to engage in any real discussion about climate change.

Massage to your tinpot dictator tendencies.

Oh, it must be nirvana to you.

Bernard,

Are you saying that Tim Curtin has slipped past the Censor?

Heretic! BURN HIM!

How much does your Uni pay you to surf all day long at taxpayers' expense? Do you flit from Deltoid to Twitter to Facebook, and then go home? It'd be interesting to work out a cost-per-word for you and Jeff Harvey. Or do you write your drivel in your spare time?

Can anybody back up the claim that Tim Lambert is a "computer scientist"? What does he actually do?

Paul UK @ #56: No, I hadn't read Caroline Notmay's response.

I wasn't aware of a Global Cooling movement. Unless we're talking about the next ice age, I think any such movement would be as unwelcome as the IPCC. Apocalypse stories are as old as the hills; you'd think that modern man would be too sophisticated to fall for it every time (and the next one!), but it's just human nature I guess.

I also wasn't aware of reserch establishments being closed down. Even if there were secret cabal of denialisti working in the Tindall Centre, holding meetings at remote beauty spots and posting lookouts in case the Met Office bosses sent snoopers, the conversations would go like this:

"Hey, did you see that the Maldives government is holding cabinet meetings in scuba gear?!"

"Yeah, they've swallowed the scare story big style."

"So, have you sold your cottage on the coast?"

"No way, mate, it's good for a few centuries yet. But I told the neighbour that the waves will be lapping round his ankles next year. He's selling it to me at half price."

"Like the student in the Canterbury Tales! Brilliant! You bloody crook, you. Here's another line we can borrow: The nuclear fusion boys say that there will be fusion power stations in fifty years. They've been saying it since 1960, and nobody calls their bluff!"

For the Tindall boys to 'come out' would be writing their own P45, so I don't jolly well think so!

Can anybody back up the claim that Tim Lambert is a "computer scientist"? What does he actually do?

Actually Hans and his girlfriend Soyung who were staying with us until yesterday are real people, who could not believe it when Lambert banned me yet again even from the thread in my name which mean that I could no longer defend myself from attacks on me and my ideas. So they were glad to help me get round the ban knowing of course that my style would sooner or later give me away. You will all be glad to know they are now fulfilling visa requirements by doing farm work for 3 months at a remote NSW location sans internet access.

If I am allowed one final comment, Lee's silly equation remains at variance with the monstrous error at the heart of Zhao and Running. In algebra, A is the stock of CO2, dA is the net addition from gross E, CO2 emissions, less Uptakes via NPP (and some oceanic solution in addition to oceanic NPP). The ratio of E to U has demonstrably remained remarkably constant on average since 1958, (since 1850 according to Knorr GRL 2009), so that dA is only 44% on average of annual E. That simple arithmetic from the actual statistics on the flows in dA, E and U recorded by Le Quere et al totally refutes the claim by Zhao and his Running dog that NPP has declined since 2000.

If it has, what has happened to the 52.08 GtC of the total 92.7 GtC of E from mid-2000 to mid-2009 that did not become Airborne? Actual dA in that period was 40.63 GtC, or 44% of total E.

Lee, I leave as an exercise for you what are the respective growth rates of E and U since 1958? Hint: the trend in the Airborne Fraction was actually down from mid-1959 to mid-2007, pace Raupach, but any given yearâs reading depends on ENSO.

"The professor [Phil Jones] at the centre of the 'Climategate' affair successfully received more than £13 million ($19 million) in research funding".

Why does he not drive a Merc?

Jeff Harvey:I believe that the Gleadow study on cassava is questionable at best,fraud at worst.For one thing it was funded by the far-leftwing Finkel Foundation.For another thing her claims about cassava root yields are completely refuted by Imai[1984]This study showed that dry matter yield was increased by 54% for high CO2 only,and 150% for high CO2 AND high temp.Every metric for cassava growth in elevated CO2 was greatly increased in this study.Other studies show support her findings on leaf cyanogenic glycosides

Who is Monckton gonna sue this time.......himself?

So isnt CO2 plant food after all? It's been a long known fact that plants benefit from extra CO2 drastically, thats why even in real greenhouses concentration is artificially raised to 1000ppm.

Are you being a photosynthesis denier?

> Are you being a photosynthesis denier?

Did you actually watch the video? The point is that while plants do use CO2, the net benefit to crop yields from increased atmospheric concentrations is negative.

J:

> [...] a long known fact [...] even in real greenhouses concentration is artificially raised to 1000ppm.

Are you using the phrase "long known fact" as a shorthand for "I just pulled some sciencey-sounding numbers out of my ass"?

J, what is in this bag of plant food I put my tomato seeds in?

Do you think it's CO2?

I don't think so.

Go surf on the Wiki and read the article "photosynthesis".
EVERY plant eats CO2 from the atmosphere, and the more there are it the more they benefit. You are just ridiculing yourselves to deny the fact of photosynthesis.

Frank: You can ask any serious farmer if they add CO2 to their greenhouses and the answer is: THEY DO.

> > > [...] a long known fact [...] even in real greenhouses concentration is artificially raised to 1000ppm.

> > Are you using the phrase "long known fact" as a shorthand for "I just pulled some sciencey-sounding numbers out of my ass"?

> Frank: You can ask any serious farmer if they add CO2 to their greenhouses and the answer is: THEY DO.

"You can ask any serious farmer"? Is that another shorthand for "I just pulled another random statement out of my ass"?

You're telling me that serious, serious farmers have state-of-the-art gizmos that can pump out carbon dioxide in greenhouses and calibrate its concentration to 1000ppm, and somehow this fact isn't documented anywhere in the written literature, but we have to take your word that it's all true.

"Go surf on the Wiki and read the article "photosynthesis". EVERY plant eats CO2 from the atmosphere"

Here, do some reading yourself, kid:

http://www.newton.dep.anl.gov/askasci/bot00/bot00191.htm

google: co2 research plant growth pdf face
e.g. http://www.uswcl.ars.ag.gov/pdf/uswclpubs/wclpub-1594-Pinter.pdf

some plants react positively to CO2 some do not.
Greenhouses heated by burning gas etc increase co2 by piping combustion output to green house.

face experiments increase local CO2 levels by spraying co2 into air around the experimental field.

CO2 may be a food but the other effects - increase in extreme weather events can easily negate its increased growth.

Is the crop mass increased or is it just the leaf?

frank.
Photosynthesis isn't the only effect of CO2 on a plant's growing environment.

http://www.sciencedaily.com/releases/2010/08/100809161138.htm

Not so encouraging.

> EVERY plant eats CO2 from the atmosphere, and the more there are it the more they benefit. You are just ridiculing yourselves to deny the fact of photosynthesis.

Who's denying it? You are the one ridiculing yourself by thinking the issue is as simple as that.

To run with your example, the CO2 isn't the only environmental factor that can be managed in a greenhouse; the temperature, moisture and nutrients are all kept at the optimum for the crop intended. But for crops grown outdoors (i.e. the overwhelming majority), they're more dependent on the local climate, something that stands to change for the worse in a higher-CO2 world.

How funny is the China News Guy!

And just in the interests of scientific accuracy, "eating" is a very poor metaphor for what plants do to CO2.

Jo Nova thinks climate change is "crap"!

http://img267.imageshack.us/img267/2067/tonyabbottjonova.jpg

what a joke.

some skeptics are just realising that plants need CO2, so they jump to the conclusion that unprecedented CO2 increase will be good for the planet?

plants need water too, how about we flood the entire world?

this is a great example of the sheer ignorance of warming deniers. anyone who believes this rubbish instantly discredits themselves on the subject.

EVERY plant eats CO2 from the atmosphere, and the more there are it the more they benefit. You are just ridiculing yourselves to deny the fact of photosynthesis.

The problem is that you seem completely unaware of Liebig's Law, which is the most fundamental principle of plant nutrition. I take it you flunked biology in high school.

The Royal Society published this this week or last week, among other papers: http://rstb.royalsocietypublishing.org/content/365/1554/2835.full.pdf+h… on arable yields over the next 40 years in context of warming. CO2 good, some other things good, some others bad. End result yields up 50% this paper says by 2050.

For addition of CO2 to greenhouse environments see this from the Min of Ag in Ontario: http://www.omafra.gov.on.ca/english/crops/facts/00-077.htm an early sentence: "The benefits of carbon dioxide supplementation on plant growth and production within the greenhouse environment have been well understood for many years."

As CO2 is plant food, water is plant drink. Except that too much water can wash the whole goddam field away, plants and all. Too little and the field becomes a desert. Like CO2, there are certain levels that are beneficial and others above or below that which are not good places to go.

Great video :)

Cheers - John

Roddy Campbell:

> The Royal Society published this this week or last week, among other papers: [...] on arable yields over the next 40 years in context of warming. CO2 good, some other things good, some others bad under an energy use regime which is not fossil-fuel intensive (IPCC's A1B).

Fixed.

> an early sentence: "The benefits of carbon dioxide supplementation on plant growth and production within the greenhouse environment have been well understood for many years."

Ah, OK. At long last.

I think that most of the farmers that J from post 2 knows are Mary Juwana growers. This plant does benefit from huge amounts of CO2 so, much like the dietary requirements of a human and a cow, other plants must also benefit from it as well XD

J sounds like Tim Curtin redux. I thought we'd put this "C02 will beneift plants" garbage to bed on the April Tim Curtin thread.

Evidently not.

The denialati and those pushing this line think that its perfectly OK to extrapolate the productivity of ecosystems on the basis of a few controlled experiments in greenhouses or laboratories in which plant biomass in response to increased C02 concentrations has been examined. I have news for them: the world is not an articicial greenhouse in which conditions (inputs, outputs, consumer-based processes, etc) are strictly controlled or even eliminated. In other words, natural systems do not respond linearly to the forcing of a single element! What about N? What about P? What about top-down (consumer-reglated) or bottom-up (plant-regulated) factors that determine the productivity of natural and agricultural ecosystems?

Most of those pushing this nonsense have an understanding of ecological complexity that is IMHO at the level of a grade 5 student; they expunge not only a range of other critical abiotic processes that influence net primary productivity (NPP), but more importantly critical biotic interactions in the soil and above-ground domains that critically also influence terrestrial NPP. Some estimates are that 20% of NPP is consumed by vertebrate and invertebrate herbivores, and in agro-ecosystems this figure is likely to be much higher, given that these sytems are spatially homogeneous and the crops themselves have usually been artificially selected to reduce levels of plant secondary metabolites (= allelochemicals). We know that increases in atmsopheric C02 can lead to dramatic changes in allocations of C or N to both primary and secondary metabolites, thus resulting in significant differences in plant nutritional quality between high or ambient C02 regimes. What effect this will have on herbivore fitness is anyone's guess, but there is evidence that as nutrient levels decrease in higher C02 regimes that concentrations of some allelochemicals, especially C-based ones, will increase, making plants more toxic. Thus, herbivores will have to consume more plant biomass to accrue the same level of nutrients as they did when C02 levels were lower, but in doing so they will ingest more phytotoxins. Plants have evolved all kinds of strategies to avoid being eaten, and in this scenario humans are inadvertently helping them to defend themselves better, whilst disrupting consumer based interactions and, ultimately, the structure and function of food webs and ecosystems in which they are embedded. At the other end of the extreme, plants with N-based allelochemicals may become less toxic, making them prone to increased herbivory. And let us not forget that many early successional plants are weeds which will thrive under elevated C02 regimes. They will become increasingly aggressive and will seriously affect agricultural productivity, unless new herbicides are developed and used. The end result of this great experiment is anyone's guess, but I am fed up to here with the denialist wingnut brigade spewing forth their nonsense without even a basic understanding of the broader effects of pumping more and more C02 into the atmosphere on a range of ecological processes over quite variable spatial and temporal scales. Its patent nonsense to be drawing linear positive conclusions on the effects of C02 on the basis of what we know and what we don't. There will be many nasty surprises that we could not have seen or predicted earlier.

As I said above, most of those pushing the "C02 is plant food line" do not understand any of this, so they ignore it. In my my academic position I have worked on plant-insect interactions for the past 10 years, have published many studies examining the role of primary and secondary chemistry on multitrophic interactions, and can assure you that the effects of rapidly increasing atmospheric concentrations of C02 are not going to create a wonderful green utopia. This is pure and utter fantasy. Theoretical models correalting C02 with NPP are only as good or accurate as the parameters that are fitted into them. Models that ignore key ecophysiological processes and mechanisms on NPP are, in my opinion speaking as a scientist, mostly worthless.

I realise Tim Lambert will delete this Reply to Adelady (at #10) as soon as he sees it here, so I will also post this at the one thread here where I am allowed to exercise some free speech.

[To Jarrod Welch et al, PNAS, 2010]

I am disturbed by several features of your otherwise very impressive co-authored paper in PNAS that appeared this week.

In particular I would be interested to know why the paper ignores any positive impact on rice yields from the rising atmospheric level of carbon dioxide (hereafter [CO2]) that one suspects the paper attributes to be the proximate cause of the rising temperatures that it claims will produce declining rice yields.

So far as I can see, the paper only mentions [CO2] once, and then inaccurately, as a âfixed effectâ whereby the ambient CO2 concentration is âcommon to all farms at a given site in a given season and yearâ (p.2 of online version). Sure, that is true not only for any given year but for every year, but the level of [CO2] is of course higher in every successive year, so to describe that as a âfixed effectâ is unacceptable, or so it seems to me.

That is especially the case when many thousands of papers have described both the fertilizing effect of [CO2], without which of course there would be no rice at all anywhere, and the impact of rising [CO2] on yields of all crops everywhere, whether in greenhouses, in FACE experiments, or in general, as I have myself shown in a peer-reviewed paper (2009).

Your paper assumes that the rise in [CO2] from 356.7 ppmv at end 1993 to 367.89 ppmv at end 1999 had no impact on rice yields at the locations of study, but it certainly does not verify that assumption.

To do so, you and your co-authors need to show why Krishnan et al., for example, are mistaken to have found that in eastern India while âfor every 1 °C increase in temperature, ORYZA1 and INFOCROP rice models predicted average yield changes of â7.20 and â6.66%, respectively, at the current level of CO2 (380 ppm)⦠increases in the CO2 concentration up to 700 ppm led to the average yield increases of about 30.73% by ORYZA1 and 56.37% by INFOCROP riceâ (2007:233, my italics).

Your failure even to mention the Krishnan paper when their eastern India covers your site in Tamil Nadu is not acceptable practice - except of course in Proceedings of the National Academy of Science.

It would also be interesting to have your explanation for how Vietnam managed to become the worldâs second largest rice exporter when reckoned in terms of exports as a % of its total production from 1990, despite both its own rising population and rice consumption, in the face of the alleged falling yields there from 1995-99 resulting from the adverse weather trends in Welch et al.

Even more interesting would be to have your co-author David Daweâs explanation for how in Welch et al (2009) he endorses your paperâs claim that the observed national yield growth in the Philippines was only 1.51% p.a. âat the end of the 20th century (Table 1), when in the book he edited and largely wrote for IRRI, he reports larger increases in rice yields in the Philippines, despite his claims that yields are falling in his co-authored with Welch PNAS paper.

Here is Dawe in the IRRI book:

âData from the Bureau of Agricultural Statistics (BAS) show that the average national yield increased from 2.99 tons per hectare in 1997 to 3.33 tons per hectare in 2002. How much of this yield change can be attributed to the use of quality seeds? (Quality seed as defined here includes
foundation, registered, certified, and good seeds.) Based on a large PhilRice-BAS random survey of rice farmers, the percentage of farmers who used quality seeds in at least one cropping season increased from 38% in 1996-97 to
49% in 2001-02.

The same data set showed that the average yield advantage of using quality seeds over farmersâ seeds was around 300 to 470 kilograms per hectare in irrigated areas and 500 to 650 kilograms per hectare in rainfed areas (Table 2). Thus, from 1997 to 2002, it was calculated that only around
9% of the yield increase was due to increased use of high-quality seeds. The other 91% of the gain must be due to other factors such as fertilizer or chemical
use, improved irrigation, or weather [!!!]â.

So Dawe simultaneously holds beliefs that âweatherâ can over much the same 5 years explain both rising and falling average yields in those years!

What about the rising [CO2] that in Welch 2010 causes the rising temperatures? Or do Dawe and the other authors of Welch et al. deny that rising [CO2] has ANY fertilizing effect?

Finally, please explain in what respects your paper does not fully vindicate Bernard Madoffâs version of investment analysis?

I am sorry if I appear abrasive, but, dear Dr Welch, you yourself made large claims about your paper in Science Daily, August 10, 2010: "âWe found that as the daily minimum temperature increases, or as nights get hotter, rice yields drop,â said Jarrod Welch, lead author of the report and graduate student of economics at the University of California, San Diegoâ.

That is a wholly misleading statement, and actionable had it been made in connection with an issue of shares on the NYSE.

References:
Curtin, T. 2009. Climate Change and Food Production. Energy and Environment, 20.7: 1099-1116.

Krishnan, P., D.K. Swain, B. Chandra Bhaskar, S.K. Nayak, R.N. Dash 2007.Impact of elevated CO2 and temperature on rice yield and methods of adaptation as evaluated by crop simulation studies. Agriculture Ecosystems and Environment, 122, 233-242.

> The Royal Society published this this week or last week, among other papers: http://rstb.royalsocietypublishing.org/content/365/1554/2835.full.pdf+h… on arable yields over the next 40 years in context of warming. CO2 good, some other things good, some others bad. End result yields up 50% this paper says by 2050.

It's worth pointing out that CO2 fertilisation only accounts for 13% of that increase. Also, the 50% increase is assuming that the 'yield gap' is closed, which is an optimistic assumption.

@15 Danny

I couldn't agree more. We have people trying to argue against the science of climate change who apear to be only just finding out about photosynthesis... and letting everyone know.

Congratulations to them, now they may have a chance of passing the plants unit of a high school biology class.

j:
>Frank: You can ask any serious farmer if they add CO2 to their greenhouses and the answer is: THEY DO.

Only serious farmers use greenhouses??

> Only serious farmers use greenhouses??

It's worse than that - the implication is that if you **don't** use a greenhouse you're not a serious farmer.

We have people trying to argue against the science of climate change who apear to be only just finding out about photosynthesis... and letting everyone know.

Also, human beings exhale CO2. Obviously, burning fossil fuels doesn't do anything.

http://www.nature.com/scitable/knowledge/library/effects-of-rising-atmo…

Effects of Rising Atmospheric Concentrations of Carbon Dioxide on Plants

By: Daniel R. Taub (Biology Department, Southwestern University) © 2010 Nature Education
Citation: Taub, D. (2010) Effects of Rising Atmospheric Concentrations of Carbon Dioxide on Plants. Nature Education Knowledge 1(8):21

Perhaps we should just eat global warming deniers instead, it is about all they are good for!

J the moron,
No, CO2 is NOT a plant food, any more than oxygen is an animal food. Plants need not only CO2 to grow, but nitrogen from the air and soil, minerals from the soil, and water. You think CO2 is so important for plants that we can simply increase the CO2 amounts to benefit them and ignore all the other effects that may be harmful? What idiocy!

I have a question for Anthony Cox and Tim Curtain. in talking about the effect that extra CO2 might have on plants are you saying that at this point in time the amount of CO2 in the atmosphere is increasing an dif so what is the majority source of that CO2? Adequate answers please.

http://www.sciencemag.org/cgi/content/abstract/329/5994/940

Very good video, thanks for posting it Tim.

The great thing about these videos is how complex interactive factors are put across simply and directly. All the more peculiar then that some commenters here either didn't watch the film, or are simply incapable of understanding. I notice not one of them picked up on perhaps the most disturbing aspect - the alarming rate of loss of phytoplankton, most recently outlined by Boyce, Lewis and Worm (abstract here). The notion that a critical element in oceanic ecosystems is failing is even scarier than the prospect of more droughts, floods, wildfires and heatwaves.

WTF is Tim Curtin doing on this thread?

Tim Lambert, I thought this source of inane, time-wasting blather had been qaurantined.

I just don't even know how to respond to J's ignorance.

Water is essential for humans. But drink too much of it and things get very tricky, [as this unfortunate woman found out](http://www.dailymail.co.uk/news/worldnews/article-1224051/Wee-For-Wii-w…). Of course, she died as a result.

You just can't dumb-down chemistry to the point of "you need this stuff to function, therefore any amount of it is beneficial".

> You just can't dumb-down chemistry to the point of "you need this stuff to function, therefore any amount of it is beneficial".

Nor can you dumb down the atmosphere to the point of "if more CO2 helps some agriculture in tightly controlled greenhouse environments, then more atmospheric CO2 can't lead to **any** negative agricultural consequences outside of greenhouses - where the majority of the world's agriculture takes place."

Nor can you dumb down the atmosphere to the point of "if more CO2 helps some agriculture in tightly controlled greenhouse environments, then more atmospheric CO2 can't lead to any negative agricultural consequences...

Well, I guess you can.......if you're silly and irrational about it! ;)

"what is the majority source of that CO2? Adequate answers please"

Combustion of hydrobarbons by humans in the form of coal, oil and gas.

I guess one of the things that this whole discussion enters into is whether CO2 should be classed as a pollutant when it is good for plants. Taking such a simplistic view is, of course, nonsense; nitrate is a 'plant food' as well, however this hasn't stopped NOx (which forms nitrate in the atmosphere) being quite rightly classed as a pollutant. Bottom line is that any benefit from CO2 fertilisation is completely wiped out by all the Bad Stuff that comes from elevated CO2 concentrations.

oh look: Rising temperatures reducing ability of plants to absorb carbon, study warnsResearch shows warming over past decade caused droughts that reduced number of plants available to soak up CO²

http://www.guardian.co.uk/environment/2010/aug/19/rising-temperatures-p…

"I guess one of the things that this whole discussion enters into is whether CO2 should be classed as a pollutant when it is good for plants."

How about discussing whether CO2 is good for plants?

It isn't.

Pull a plant out of the ground.

Put it in a sealed jar filled with CO2.

The plant will die.

As to whether it's a pollutant, is our intent when burning fossil fuels to make plants grow?

No?

Then CO2 produced is a pollutant.

James, I notice now you say that such a simple statement as "it's good for plants" is too simplistic.

I may have gone a little OTT.

However, still a bad idea to say "it's good for plants" when people are just *GAGGING* to misappropriate the statement for nefarious purposes.

There are at least three problems here

1. The assumption that what is good for plants is also good for the users of plants (in this case us). It aint so. You may get woody biomass, but unless it is that tyou are seeking - rather than leaf or flower or protein then it is irrelevant

2. That what is good for some plants is good for all plants. If they aren't the plants we want to help, then it is pointless

3. That the plants can take up and use the extra Co2. Again, not clear. It is contingent. Hence the FACE studies

Most FACE studies show little or negative benefit to plants used by humans and dsiruption to plant biodiversity.

Wow!

No, no, no, nooooo!

I was trying to see if I could get a straight answer out of Cohenite and Tim Curtain. I will will win a lot of money if I don't.

[Tim Curtin](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

You just can't help yourself can you? Not only did you completely and abysmally fail to justify your chemistry and biology nonsense on your second personal thread, but you had to break the rules and have your sandpit shut down.

Own goal, that.

I'm in two minds about whether that is a good thing, because I really did want to see if you were able to justify, in any way at all, any of your ridiculous claims.

I was also going to ask you whether or not you'd figured out how I interrogated the Mauna Loa data to obtain [the extrapolation that I did](http://i47.tinypic.com/x532g5.jpg). Tamino's [posted on the subject again](http://tamino.wordpress.com/2010/08/09/mo-better-monckey-business/), and I thought that now would be an apposite time to reveal one simple, parsimonious way of looking at the data.

And I was so looking forward to hearing from you afterward why a linear fit or a 2nd order polynomial one would still be better...

[Sigh.]

> However, still a bad idea to say "it's good for plants" when people are just GAGGING to misappropriate the statement for nefarious purposes.

That was me trying to give an example of deny-o-think. In my opinion, anyone who tries to use such a statement like that without any consideration for either the details or the big picture is just demonstrating how intellectually feeble they are. Or dishonest, take your pick.

"J the moron, No, CO2 is NOT a plant food, any more than oxygen is an animal food. Plants need not only CO2 to grow, but nitrogen from the air and soil, minerals from the soil, and water. You think CO2 is so important for plants that we can simply increase the CO2 amounts to benefit them and ignore all the other effects that may be harmful? What idiocy!"

Its a scientific fact that more CO2 in the atmosphere increases the crop yields. Yes, plants need other things aswell but that doesnt mean extra CO2 does not help them. You should also go back to high school and read about photosynthesis - the carbon in C is a BUILDING BLOCK, therefore it IS plant food. Millions of years ago when there was 20xCO2 in the atmosphere the plants and animals were the BIGGEST in the history of Earth.

This has nothing to do with the debate of if we should pump more CO2 or not. The discussion was about CO2 being plant food or not. And it IS plant food, there's no doubt of it. But I guess it is not allowed to speak from any potentional benefits, since CAGW-religion permits that and labels you a 'denier' if you do. Only harmful effects are allowed to be discussed at - only to cause constant alarm.

"How about discussing whether CO2 is good for plants?
It isn't.
Pull a plant out of the ground.
Put it in a sealed jar filled with CO2.
The plant will die.
As to whether it's a pollutant, is our intent when burning fossil fuels to make plants grow?
No?
Then CO2 produced is a pollutant."

Typical straw man fallacy. Plants can and will benefit from much more CO2 than the current ~390ppm. CO2 isnt about pollution, debate behind CO2 is about global warming and whether it has a significant effect. NO2 SO2 etc are pollutants which we should take care of.

*[Post from Tim Curtin sockpuppet removed]*

J:
>will benefit from much more CO2

You've [already been directed](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) to go and learn some of the basics of this subject. Your comment quoted above shows that you have not done so.

Paddy Constantine, please remain at your station. Black Helicopters have been dispatched and will be with you shortly.

Paddy Constantine, you appear to be a gullible believer in any old crank nonsense that comes along.

Why don't you detail your scientific experience so that the background justification to your obviously strongly held beliefs can be known.

My guess is that just like Tim Curtin you wouldn't know one end of a test tube from the other, but perhaps that's unfair.

> Its a scientific fact that more CO2 in the atmosphere increases the crop yields.

That's so simplistic - or maybe "incomplete" is a better description - that on its own it's genuinely misleading.

It depends on whether CO2 is a limiting factor or not.

It depends on the particular plant.

It depends on whether you measure the total biomass or **just the bits that humans (or animals) can digest** - and if you care how well they can digest it because the composition can change significantly.

It depends on whether you lose more of your crops to adverse weather conditions due to climate change associated with the increased CO2 (just a few hours of excessive night-time temperatures at one point in the growing cycle for some types of rice can seriously damage yield).

It depends whether you can keep your plants producing at high levels because the CO2 and temperature give a big boost to a bunch of plant and animal competitors to your crop.

> ...it is not allowed to speak from any potentional benefits...

I don't have a problem with speaking of potential benefits, as long as it's a balanced assessment. And the balance of the evidence makes it very difficult to say that more CO2 will benefit agriculture directed to human benefit, because it's very difficult to rule out significant negative impacts that more than wipe out any improvements you hope to get from the CO2 itself.

Dang.

Paddy Constantine was a Curtin sock puppet?

I wish I'd caught his 'wisdom' before it was tidied away.

And it throws a whole new light on the original several posts...

@Lotharsson:
"That's so simplistic - or maybe "incomplete" is a better description - that on its own it's genuinely misleading.
It depends on whether CO2 is a limiting factor or not.
It depends on the particular plant.
It depends on whether you measure the total biomass or just the bits that humans (or animals) can digest - and if you care how well they can digest it because the composition can change significantly.
It depends on whether you lose more of your crops to adverse weather conditions due to climate change associated with the increased CO2 (just a few hours of excessive night-time temperatures at one point in the growing cycle for some types of rice can seriously damage yield).
It depends whether you can keep your plants producing at high levels because the CO2 and temperature give a big boost to a bunch of plant and animal competitors to your crop.

I don't have a problem with speaking of potential benefits, as long as it's a balanced assessment. And the balance of the evidence makes it very difficult to say that more CO2 will benefit agriculture directed to human benefit, because it's very difficult to rule out significant negative impacts that more than wipe out any improvements you hope to get from the CO2 itself."

How about some peer-reviewed literature then?
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V8W-4894P5X-…
"This paper presents a detailed analysis of several hundred plant carbon exchange rate (CER) and dry weight (DW) responses to atmospheric CO2 enrichment determined over the past 10 years. It demonstrates that the percentage increase in plant growth produced by raising the air's CO2 content is generally not reduced by less than optimal levels of light, water or soil nutrients, nor by high temperatures, salinity or gaseous air pollution. More often than not, in fact, the data show the relative growth-enhancing effects of atmospheric CO2 enrichment to be greatest when resource limitations and environmental stresses are most severe."

Pay attention to the last phrase - with more limitations the benefit will be actually MORE!

If we also take in to account how the CO2-concentration is rising - only half what we pump (even that the emissions have rised exponentially still its always just 50%!) is constantly stayin in the atmosphere. Why? As if the ecosystem was hungry for more CO2.

Only valid point against this argument is that if it causes significant warming and if this warming will have a negative impact (I guess it may also have many positive impacts but those are not discussed in the IPCC scare-science) nullify any benefits CO2 might have. It all comes to the climate sensitivity (clouds) which yet waits to be proven positive or negative...

All serious comment on the Russian Heat Wave and the Pakistani Floods have focused as changes in the Jet Stream as the cause.
I have not found any serious commentator trying to link CO2 and the Jet Stream.
This video only adds confusion, is cheap propaganda, what next blame CO2 for the Second World War and 9/11?

My link was broken. The reference was:
Idso, K.E. and Idso, S.B. 1994. Plant responses to atmospheric CO2 enrichment in the face of environmental constraints: A review of the past 10 years' research. Agricultural and Forest Meteorology 69: 153-203.
can be found with Google.

The extra heat energy CO2 holds in the atmosphere is causing disruption to what are generally well established weather system patterns that farmers for instance have grown used to over generations. The jet streams are part of those weather systems.

While it's difficult to attribute individual events to CO2, it is consistent with [IPCC predictions](*http://www.ipcc.ch/publications_and_data/ar4/syr/en/spms3.html) of more extreme and more frequent extreme weather events.

J:

By your (and Idso's) 'logic', it's beneficial for one to cut off his own legs. Because when he does so, he'll grow 'faster', in the sense that his height will experience a larger "percentage increase" when he grows (even if the absolute increase is the same).

You fail.

Drought-Induced Reduction in Global Terrestrial Net Primary Production from 2000 Through 2009,
Maosheng Zhao* and Steven W. Running :

http://www.sciencemag.org/cgi/content/abstract/329/5994/940

Plain English report:

http://news.discovery.com/earth/worlds-plants-wilting-in-the-heat.html

> Why? As if the ecosystem was hungry for more CO2.

That's a very silly comment.

If my land gets flooded is it "as if the land is hungry for more water"?

> I guess it may also have many positive impacts but those are not discussed in the IPCC scare-science

I take it you haven't read the IPCC report? Or considered any of the (limited set of) factors I earlier suggested you might like to take into account?

Why is that?

> This paper presents a detailed analysis of several hundred plant carbon exchange rate (CER) and dry weight (DW) responses ...

...because as we all know what humans most care about is dry weight alone, not nutrient content or digestibility or robustness across varying weather conditions or resistance to attackers...

Try reading a bit more widely. (There's a bunch of responses to similar claims about CO2 being fantastic for agriculture on the Tim Curtin thread.)

I also note you have STILL failed to address the literature that discusses any number of significant negatives from anthropogenic climate change. Why is that?

Suibhne:

>*All serious comment on the Russian Heat Wave and the Pakistani Floods have focused as changes in the Jet Stream as the cause. I have not found any serious commentator trying to link CO2 and the Jet Stream.*

A disingenous post from Suibhne, trying to evade the [predicted link](http://www.nytimes.com/cwire/2010/08/18/18climatewire-pakistan----a-sad…) between higher temperatures and such disasters.

>*Most experts are still cautioning against tying any specific event directly to emissions of greenhouse gases. But scientists at the World Meteorological Organization (WMO) in Geneva say there's no doubt that higher Atlantic Ocean temperatures contributed to the disaster begun late last month.*

What a creep Suibine is.

chek:

While it's difficult to attribute individual events to CO2, it is consistent with IPCC predictions of more extreme and more frequent extreme weather events.

Individual events are not evidence of the warming effect of CO2 and I think it's important to avoid getting into any argument about whether they are or are not. The logic is more like the other way around, e.g. heat waves are likely warmer than they would have been without global warming

Millions of years ago when there was 20xCO2 in the atmosphere the plants and animals were the BIGGEST in the history of Earth.

Bigger than the blue whale?

Actually, bigger animals would only be possible in an atmosphere with greater amounts of OXYGEN, not carbon dioxide. You are still a moron, J.

J.

Your post [here](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…), and those previous, are so full of nonsense that it would take an entire thread to discuss it all.

You're not a scientist, are you?

j:
>I guess it may also have many positive impacts but those are not discussed in the IPCC scare-science

Is it more of a case that you expect science to return results that are beneficial to humans?

Should science only be beneficial?

Is it that your expectations are the problem?

Fakermans Post 60 is typical of the intellectual bankruptcy of the warmest tendency.
When asked to supply any SERIOUS commentary linking the Jet Stream with CO2 he resorts to a warmist propaganda centre (E&E) for his only quote.
He fools no one but himself!
Probably he doesn't read any serious sources as they would just get him even more confused.

@Lotharsson:
"That's a very silly comment.
If my land gets flooded is it "as if the land is hungry for more water"?"

If the land instantly sucks half of the water you pour into them, then they are thirsty yes. But your comparison was not really comparable to mine, its more like a straw man argument, since too much water will kill the plants (any CO2-amount we could ever pump wont suffocate em).
What warming would do if CO2 caused significant warming is another discussion.

"I take it you haven't read the IPCC report? Or considered any of the (limited set of) factors I earlier suggested you might like to take into account?
Why is that?
This paper presents a detailed analysis of several hundred plant carbon exchange rate (CER) and dry weight (DW) responses ...
...because as we all know what humans most care about is dry weight alone, not nutrient content or digestibility or robustness across varying weather conditions or resistance to attackers..."

Well, do you have any reference that increased CO2 will just make the undigestiable parts bigger, but not crops or leafs?

"Try reading a bit more widely. (There's a bunch of responses to similar claims about CO2 being fantastic for agriculture on the Tim Curtin thread.)
I also note you have STILL failed to address the literature that discusses any number of significant negatives from anthropogenic climate change. Why is that?"

The whole question is IF warming equals bad and IF CO2 causes significant or any warming at all. It all comes to the cloud feedbacks which are found to be negative in the tropics (Spencer et al 2007), and the latest finding of still missing hot spot (MMH2010 debunking Santer et al) supports this theory. Models do not know how the energy flows in planet earth since model results strongly disagree with the observations (just looking at the global trend is way too simplistic way for 'verifying' models. Garbage In, Gospel Out.

Just wait and see what CERN CLOUD-experiment results tell. There are more than ten papers about to be published in a few months.

And the harm of warming - omg. Perhaps you should try global COOLING (which is slowly happening if we look the last 10 000 years). Read the history books how humankind suffered in the LIA. Lets enjoy the Holocene interglacial while it lasts.

j:
>What warming would do if CO2 caused significant warming is another discussion.

Actually no it isn't. You can't isolate one from the other.
What the science is about is whole system analysis.

The reason this discussion exists at all is because you and others cherry pick issues.

j:
>The whole question is IF warming equals bad and IF CO2 causes significant or any warming at all.

You express double standards in one post!
Earlier in the same post you state that warming is a separate issue.

You can't guide the direction of the discussion, if you yourself are changing/breaking your own rules of engagement.

To clarify, you stated the discussion was about CO2 being plant food and that the warming issue was for another discussion.

I love how the video says that plankton populations are declining, yet makes no connection of this trend to AGW. It seems like they are counting on most people just assuming that AGW is the cause. The truth is that no one knows the cause of the decline.

No one knows the cause of the MASSIVE 6% decline. (6% sounds like an error bar to me.)

[These fluctuations are strongly correlated with basin-scale climate indices, whereas long-term declining trends are related to increasing sea surface temperatures.](http://www.nature.com/nature/journal/v466/n7306/full/nature09268.html)
In other words, manifestations of AGW.

> If the land instantly sucks half of the water you pour into them, then they are thirsty yes.

My point was not to make a high-fidelity analogy. It was to point out the silliness in imputing "what the ecosystem **wants**" (disregarding the apparent anthropomorphisation) from "what happens to it". In particular, since you're talking about crops, you fail to distinguish between what the land can accommodate and what's good for agriculture.

> ...(any CO2-amount we could ever pump wont suffocate em)...

You are cherry-picking the **effects** you want to take account of, and **discounting** the rest - now on the negative effects side, just as you did earlier on the positive side.

And you're not even cherry-picking the "positive" effects very well, because you're avoiding picking the measures that human *actually* care about.

> Well, do you have any reference that increased CO2 will just make the undigestiable parts bigger, but not crops or leafs?

No, because that's not what I claimed.

The total biomass can increase, but the total human-usable yield can still decrease.

As I said, go read [this Tim Curtin thread](http://scienceblogs.com/deltoid/2010/04/tim_curtin_thread_now_a_live_s…) where he makes essentially the same blinkered claim as you, and gets knocked down again and again and again - in far more detail than I have provided here, and with references.

[J](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

That fact that you do not understand the significance of several more degrees of global warming, is sufficient to indicate to anyone who does understand the import of such a change, exactly how

1. ignorant
2. uneducated
3. poorly-informed
4. deliberately misrepresentational
5. outright lying

you are.

Take your pick of any or all of the above - there are no other viable alternatives.

Normally I take interest when twits like J show up since many times the counter posts bring up information and links of which I wasn't aware.
But this is cracked record nonsense.
J is either a simple crank (and I do mean simple...) or he/she/it is a paid denier shill.
Take your pick, but this is shit that the bull would be ashamed of....

Juice,

You'd [come across](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) as less of a fool if you [read the paper](http://www.nature.com/nature/journal/v466/n7306/full/nature09268.html) before commenting on its merits. The video references the paper, and surprisingly enough the paper supports the point the video is making.

Bernard, you must more careful with your look at climate change. Some, of which provide a composition for a collecting complaint like you.

Your anonymity is here no defense against a sub poena to Lambert to reveal, who you are. For example the Australian academy of the science of report (August 2010) first chart (fig. 3.1, p. 7) tenor to show "the global external laughed temperature anomaly in that compare to 1951-1980" of 1850 to 2010 (CRU) or of 1880-2010 (GISS, NCDC). The "anomaly" are creates external laughed "warmed" have chiefly negative of 1850 or 1880 until the '1940's, and through it the impression of the positive anomalies there the '1970's, that there of global temperatures.

That impression is alone an artefact of the absence of that measurements helpful to show the temperature over most the globe until the '1940's, above all in the tropics, and that meant that the Fig.3.1 of the AAS of report is deceitful. It is reported especially objectionably for the authors of the AAC to not to have tested its sources when both THE NCDC and GISS makes no secret the lacking of even so much, like 50 percent global cover of helpfully measured external laughed temperatures before the 1940 how through the cards of NCDC, revealing almost complete absence of such records over the hot tropics of the world before 1950 shown, during the "temperature anomaly" of to years 1950-1980 in the Fig.3.1 of the report include the tropics.

That mean external laughed a misleading increase in the claimed global temperature of the reason period of 1950-1980 that the tropics includes through exclusion of the tropics before 1950. Similarly the fig. the 3.2 showing of the report excludes extend the "anomaly" in the course of the period 2005-2009 helpful records over much of the cold higher because they diminished cover (GISS, 2010). Above all, both the former Ussr and Canada has extend diminished sharply its helpful temperature cover of its cooler and higher since 1990. Shortly said, Bernard J, in your last post here,i find highly incorrect.

Apologies for my English

"Your anonymity is here no defense against a sub poena"

It's called "subpoena".

One word.

"the global external laughed temperature"

what is a global laughed temperature?

"That impression is alone an artefact of the absence of that measurements helpful to show the temperature "

Oh look. More gibberish.

"Apologies for my English"

Nope, not accepted. Because the english is not the problem, the gibberish nonsense is.

Heck, you can't even QUOTE english correctly!

>Above all, both the former Ussr and Canada has extend diminished sharply its helpful temperature cover of its cooler and higher since 1990.

I think this is a citing of the widely debunked station dropout meme.

Although I'm not entirely sure...

I think you're right Stu.
It's AKA clause one of the hardy classic meme "The temperature record is unreliable".
Clause two of course is "... and the scientists are dishonest".

The same old, same old run of the mill denial.

This is actually scary...

I try to follow the global warming debate and is clearly on the side that says that increased CO2 caused by human activities is increasing global temperatures and we most do something about it. My opinions are partly based on the opinion in blogs like this and the input from commenters, which normally sound to have good insight.

However, when something is discussed that I actually now about- the effects of CO2 on photosynthesis and growth is discussed, I see the voice of reason, J., being bashed with bogus arguments.

I hope you know more about global warming than you do about photosynthesis, because otherwise I have to reconsider the evidence and conclusions presented here concerning global warming.

Weird how many people have ideas about the legal system being brought to bear - and how many of them are coming from the same "scientific" perspective.

Monckton threatens lawsuits at the drop of a hat, the NZ Climate Science Coalition(?) files suit to force a judge to force someone to invalidate a temperature record that may or may not inform government policy, Virginia(?) AG Cuccinelli (sp?) in the US tries it on against Mann's university, Tim Curtin has all sorts of entertaining but wacky fantasies about using law enforcement and the legal system against some of his detractors, and now Hans who seems to have used a not-particularly-great automatic translation system somehow implies that Bernard could face legal proceedings on what seems to be rather ... fanciful grounds.

The last are also quite amusing - apparently Hans thinks there are issues with GISS/NCDC/CRU data, so Bernard, who AFAIK has not been associated with any of those organisations, is at risk of appearing in some unspecified form of legal proceedings? Someone needs to concentrate on fiction.

You know, it's almost like they can't get a robust scientific case together, so they're trying other avenues...and half of them haven't a clue about how the legal system works.

(Oh, and Hans - it may be merely that your comprehension of English is lacking which could be entirely understandable if it's not your native language, but your comment appears to rely on misunderstanding Bernard's last comment to which you refer as "highly incorrect".)

> This is actually scary...

You're right. Your comment is actually scary, because you think that you should form an opinion about climate science from blogs, and worse - that you should discount climate science because of something said in a video about photosynthesis (what's more, something you claim is wrong, but don't bother to specify).

>*I see the voice of reason, J., being bashed with bogus arguments.*

Care to cite an example of the bashing with bogus arguments that you claim Chondrus?

Chondrus,

When you write, "I see the voice of reason, J., being bashed with bogus arguments", it seems to me that you give away the fact that you know nothing whatsoever about plant ecophysiology and the importance of scale in ecology.

I think that J's simple arguments have been blown out of the water. In my first post on this thread (# 21) I alluded to the effects of increased atmospheric C levels on plant stoichiometry - meaning how this will affect levels of other vital nutrients such as N and P, as well as on other primary metabolites such as soluble amino acids and proteins. Moreover, plants have evolved chemical defences to avoid being eaten - these are usually based on foliar N or C. As concentrations of C increase, plant biomass may increase but quality per unti of biomass will decrease owing to the loss of proteins and a concomitat increase in phytoxins that are C-based, or a decrease in phytotoxins that are N-based.

These effects will ripple up through food chains because the fitness of herbivores and their natural enemies is strongly affected by copncentrations of primary and secondary metabolites in plant tissues; plant-plant compeition will also be affected through possible effects on allelopathic compounds. Ultimately, changes in plant quality will be manifested horizontally through broader ecological communities. There will be many possible negative consequenses, and, most worryingly of all, nasty surprises in store. This is the outcome of the global human experiment, for that is what it is. It is therefore utter rubbish to argue with any level of confidence that nature benefits from increased atmsopheric C02. IT MOST CERTAINLY DOES NOT, at leat in the time scales involved. Natural systems have evolved over many thousands of years under relatively low ambient C02 regimes. A sudden spike in these due to the human combustion of fossil fuels is challenging theses systems and the species that make them up to respond at time scales which represent the blink of an evolutionary eye. The result will be, in concert with other anthropogenic assaults across the biosphere, the unraveling of food webs and the simplification of ecological networks. This will reduce their stability and make many more prone to collapse. At the same time the flow of vital ecological services that sustain civilization may be disrupted.

But J is clearly not a scientist (I am, and much of my research involves plants and insects) and he/she apparently does not understand one iota of this, and instead relies on cutting and pasting material from web sites like 'Co2-Science' written up by the Idso clan and their web site which has alleged links with the Western Fuels Association - a coal industry lobbying group. In my opinion this makes any of their 'conclusions' suspect.

So, Chondrus, go ahead, believe what you like. But if you think for a nanosecond that J's views are a 'voice of reason' on this thread then methinks you have a helluva lot to learn about science and ecology.

"(Oh, and Hans - it may be merely that your comprehension of English is lacking which could be entirely understandable"

But his language translation is irrelevent when he's apparently quoting the content of a paper as: "the global external laughed temperature anomaly in that compare to 1951-1980"

Here is is quote:

+++

For example the Australian academy of the science of report (August 2010) first chart (fig. 3.1, p. 7) tenor to show "the global external laughed temperature anomaly in that compare to 1951-1980"

+++

Australian report would be in English, yes?

No, I don't think Hans is really that bad at english or, if he is, he's been coached as to what to say.

What going "english is not my language" does for him is allow him to make up gibberish that NOT ONE PERSON understands as if it explains how everyone else has it wrong without that horrible risk of being corrected that can happen when you state your position.

Apologies for my bad English in my last, my Korean girl friend was not around, and her English is much better than mine!

Wow: our dog has better understanding than you, its R2 correlations are always at least 0.99 (ever heard of Pavlov?).

What I tried to say before my German-English translator interfered, was that "global" temperatures before say 1940, when the coverage was less than 50% of the globe, was "anomalised" to the period 1950-1980, when it finally reached 80%.

Stu: Inspection of CRU, NOAA and GISS shows their cold statistics in 1850-1940 exclude the tropics before 1940, and their hot statistics after 1990 exclude cold places after collapse of USSR in 1990 (and Canada's Alaskan etc thermometers' southward shift after 1990, see E.M. Smith and GISS).

Chondrus: You are a rare voice of intellectual honesty here. None of Tim Lambert and his grovelers, especially Jeff and Bernard, has any understanding generally of what photosynthesis involves.

Jeff when he says: "in my first post on this thread (# 21) on the effects of increased atmospheric C on plant stoichiometry - significantly, how this [affects] other important nutrients such as for example N and P [and] other primary metabolites such as for example soluble amino acids and proteins...".

What only slightly surprises me is that Jeff holds down a post in the very tolerant Netherlands, where they correctly consider that it is cheaper to align him to some whacky institute than to a home for the absurd.

His comment that rising CO2 can be treated as if concomitant increases in N & P etc are impossible leads to this demonstrably insane comment:

"It is therefore utter rubbish to argue with any level of confidence that nature benefits from increased atmospheric C02". Yet we have, with nearly 7 billion people eating more food-embodied carbon now than one billion did in 1800.

Jeff, you are a lovely guy, let's meet in Berlin some day, and let me try to explain why you are tragically wrong, tragically, because you are determined to visit famine on 10 billion people by 2050.

"Wow: our dog has better understanding than you, its R2 correlations are always at least 0.99 (ever heard of Pavlov?)."

Your english has suddenly improved, Hans. Isn't that interesting.

The content is still negative. Not so interesting.

Now, why did you quote a paper in English after running it through an English-German translation then through a German-English translator?

Your dog probably understands logic better than you do.

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ì´ì°ííìë ì¸ë¥ì 문ëªì ë°ì ìí¤ë ì¤ìí ìììëë¤.
íêµììë ìì´ ì¤ì´ë¤ê³  ìì§ ììµëë¤.
ì¤ì´ë¤ê³  ìë¤ë©´ ê·¸ ì´ì ë ëë¶ë¤ì´ ì¤ì´ë¤ê³  ì기 ë문ìëë¤.
í¹ì ì구문ëªì ìí¥ì¼ë¡ ìì ë§ì´ ë¨¹ì§ ì기ë문ìëë¤.

-In English

I am Hans girlfriend. I have lived in Korea for many years, but i have never experienced global warming due to increased Co2. This increased plant growth, and developed our world. If any reason for a decrease in rice yields it is because people no longer wish to farm it. Instead opting for more profitable options. Otherwise I see no difference in rice yields. Sorry for Hans earlier attempt, I am pleased he is trying to improve his English!

Hans,

Your post is quite honestly hilarious. And I mean this in terms of its lack of scientific acumen. I would like you to provide even the tiniest bit of evidence that increases in crop yields had anything to do with increases in atmsopheric carbon dioxide. You are making the cardinal sin of establishing causation on the basis of one (your preferred) correlation. The fact is that crop yields increased due to technological innovations, such as intensive agricultural practices, including applications of pesticides and more efficient fertilizers etc. Although, as many now know, these have deleterious effects which are being borne out in the longer term.

Please also explain why the planet quite recently evolved and sustained higher biological diversity at any time in the planet's history when ambient levels of C02 were quite low, at least in comparison with many periods in the Earth's history.

I will refrain from discussing certain aspects of plant physiology here because it is quite clear to me that you do not understand even the most basic terms. Do you know anything - and I mean anything - about primary and secondary plant chemistry? About the role this plays in nature?

Lastly, Hans, are you a scientist? What expertise do you possess in plant science or agronomy? I think I know the answer to that question. Yup, bring on Dunning-Kruger!

Here's a recent study in Nature which addresses some of the physiological changes that occur in plants as C02 increases...

http://www.sciencemag.org/cgi/content/full/328/5980/899

http://indymedia.org.au/2010/05/14/rising-carbon-emissions-threaten-cro…

The bottom line is that those pushing the 'C02 is plant food' gibberish see nature in simply linear terms. Cause and effect relationships therefore, in the view of those pushing this line, are simple and positive. But as I said above, they are not. Ros Gleadow's research in Australia shows that plants with C-based allelochemicals may invest more C into phytotoxins, whilst shunting out plant nutrients to compensate. This means that herbivores will have to consume more plant biomass to accrue the same level of nutrients they did before under lower C02 regimes, but at the same time that will ingest more plant toxins. Plants did not evolve to be eaten and most species possess a veritable armory of chemical and morphological defenses against herbivores and pathogens.

Plants with N-based phytotoxins may also become less-well defended. Given that many of our most important crops have been artificially selected to reduce levels of phytotoxins, its possible that plagues of inext herbivores will become more prevalant in response to concomitant changes in primary and secondary plant chemistry under elevated C02 levels. Who knows... the problem is that ecological mechanisms generated at small scales are integrally connected with more deteministic systemic proceses occurring at larger scales. The outcome of pumping more and more C02 into ther atmosphere will differentially affect species in food webs, unraveling many of them.

I would like to know from Hans what expertise he possesses to be able to make the arguments that he does. How many empirical studies have you performed, Hans, in which you have examined the relationship between C02, plant fitness and effects on consumers up the food chain? I ask this because it is not possible to predict with any accuracy the broader effect of the global experiment on natural systems, and no scientist worth his money would conclude on the basis of all that we do not know that the end result will be beneficial for humanity. There are too many biotic and abiotic processes involved of which we understand very little.

"I am Hans girlfriend."

Ah, yes, good old Pamela.

I know her quite well.

Come on, some noname posts on here to speak for all China.

Yeah, I'm really digging that the Asians would rather starve than work to bring in all that rice. Just too difficult...

And it's completely acceptable that this information comes unsolicited from one Korean on the internet. SHE would know what the entire Far East farming community is doing.

Hans' foray into English reminds me of Mark Twain's re-translation of "[The Jumping Frog of Calaveras County](http://members.cox.net/deleyd/religion/solarmyth/frog.html)." Worth a read, for those who've never encountered it.

Ummm... I mean Twain is worth a read. Not Hans.

"Jeff, you are a lovely guy, let's meet in Berlin some day, and let me try to explain why you are tragically wrong, tragically, because you are determined to visit famine on 10 billion people by 2050."

Yet according to Hans' "girlfriend", the farmers are the ones who are bringing famine because they can't be bothered farming:

"If any reason for a decrease in rice yields it is because people no longer wish to farm it. Instead opting for more profitable options."

Which to believe...

> ...its R2 correlations are always at least 0.99... Yet we have, with nearly 7 billion people eating more food-embodied carbon now than one billion did in 1800. ...let me try to explain why you are tragically wrong, tragically, because you are determined to visit famine on 10 billion people by 2050.

Sounds like a Tim Curtin sockpuppet to me, but I have no evidence either way.

>"let's meet in Berlin some day, and let me try to explain why you are tragically wrong, tragically, because you are determined to visit famine on 10 billion people by 2050."

Why meet in Berlin when han's can't provide evidence to substantiate his claim in text? hans text is the format for this debate, text allows proper citation of credible evidence. Something you are failing at.

BTW, implicit in your (unsupported) claim is a claim that advances technology and economic growth visit famine on 10 billion people by 2050 if we fail to also further increase CO2 concentrations. However also implicit in your (unsupported) claim is failure to count the losses of production due to increased heatwaves, flooding and drought, pests, desease and weeds. And a complete failure to factor in the effects post 2050.

> If any reason for a decrease in rice yields it is because people no longer wish to farm it.

I suspect not. The scientists aren't dumb enough to use total annual yield for a country or region to infer climate-change effects on agriculture. They measure production **per unit area**.

> And a complete failure to factor in the effects post 2050.

Yep, it's a standard Tim Curtin-like false accounting.

Which is ironic because in his thread he couldn't help but allege every few dozen posts that scientists or the IPCC or other commenters were engaged in "Madoffian" levels of false accounting.

I love Tim's Madoff references...
If only Hans had accused someone of being madoffian, or neo-malthusian, we'd know it's a sockpuppet for sure.

One problem with the video, though, is that one aspect of CO2 is its fertilisation effect, and I think a lot of the debate skirts around the issue. We seem to get a lot of nutters coming up with this one and debate sometimes degenerates into time-wastage.

I think it needs to be perfectly clear that climate scientists DO NOT forget the CO2 fertilisation effect, that it's basic biology that RuBisCO is undersaturated under current conditions, though so are many other nutrients, and that this is in fact taken into account by climate models.

And the fact that CO2 is a plant nutrient has no bearing whatsoever on its effects on climate. Once the vegetation feedback has been worked out, we should all be moving on.

I originally responded to Hans less than a couple of hours after his first post, but my reply, having more than 3 links, is still in moderation. It might not actually make it through, as I was rather snarky in my tone...

Nevertheless Hans, his girlfriend, Tim Curtin, and any others who subscribe to the magic of CO might pause and consider that [for the last decade productivity has been compromised](http://www.sciencemag.org/cgi/content/abstract/329/5994/940), exactly as Jeff Harvey, myself, Lotharsson, MFS, Chris O'Neill, jakerman, dhogaza, and a cast of dozens of others have been pointing out for the several years since Curtin first raised his nonsense on Deltoid.

Please note, Hans/Curtin, I get no satisfaction from being right, and I am sure that none of the others here do either. As an ecologist I know that this spells doom for many species, now and the more so into the future. Quite aside from the neventual implications to humans and human societies.

And for the record Hans/Hans' girlfriend, I have a very detailed understanding of not only the biochemistry of photosynthesis, but of its dynamics in an ecological context. Just as Jeff does, I find it frustrating to have to explain ad nauseum such complex, multi-factor rate-limited processes to uninformed people: explaining why your presumption that simply increasing CO concentration will automatically increase global primary productivity is wrong isn't worth the repeating for the umpteenth time. If you really want to know, spend some time reading either of Tim Curtin's threads here.

I will try one analogy though... would increasing the distance that an accelerator pedal can be pressed down increase the maximum speed of a motor vehicle? Why/why not?

> Nevertheless Hans, his girlfriend, Tim Curtin...

That second comma was important on my first quick skim of your comment!

> ...the magic of CO...

Presumably you meant CO2...

Gee, J disappears and Hans shows up...
maybe Hans girlfriend is J's sister?

Chondrus, J, Hans, Hans' Korean girlfriend, Tim Curtin's Dead Sockpuppets Club et al.: I find it very frustrating that we have, in this very thread, at least two scientists in the relevant field patiently and with increasing, understandable exasperation explaining why 'more CO2 is ah-okay for our nutritional basis' cannot be generalised thusly and why multiple limiting factors are at work that need to be ALL taken into account, which you *__consistently__* ignore. And that's not even counting the other commenters pointing you to literature that says the same.

Hans, you seem to have a little trouble with the English language; happily, I know German: Was Sie als "Argumente" vorbringen sind wenig mehr als Allgemeinplätze, ohne jegliche wissenschaftliche Basis.

There, had to get that off my chest.

/rant

Halo Jason: Also sprach Zarathustra!

Jason : "Was Sie als "Argumente" vorbringen sind wenig mehr als Allgemeinplätze, ohne jegliche wissenschaftliche Basis"

Jason,i cant agree with what you have said: " I find it very frustrating that we have, in this very thread, at least two scientists in the relevant field patiently and with increasing, understandable exasperation explaining why 'more CO2 is ah-okay for our nutritional basis' cannot be generalised thusly and why multiple limiting factors are at work that need to be ALL taken into account".

The video which began thread often rubbished Chris Monckton's correct assertion that CO2 is plant food. In video blamed the floods in Pakistan and fires in Russia on CO2, but overlooked big freeze in Bolivia and early snow in both Russia and Switzerland as being also due to versatile rising CO2.

The video praised dishonest paper by Welch & co which denies any role at all for CO2 in the actual increase in the growth rate of rice yields which claims is falling when a FAO shows it has been rising just about everywhere.

The truth is that as I have already said here, we all eat and drink stuff that is mostly carbohydrate, which embodies carbon from photosynthesis of atmospheric CO2. Reducing that CO2 now proposed MUST reduce the feedstock all living matter. So there are benefits from that action plan for at least some of the dumkopfs that inhabit this space. Thanks again to SoYoung for this. Regards to experience in the field, I prefer to remain anonymous for personal & professional reasons.

"The video which began thread often rubbished Chris Monckton's correct assertion that CO2 is plant food."

It isn't plant food.

Open up your gro-bag that you plant your tomatoes in.

Is it stuffed full of CO2?

No.

"we all eat and drink stuff that is mostly carbohydrate, which embodies carbon "

So is carbon human food?

No.

If we replaced 90% of your dinner with carbon, would that dinner still feed you for a normal meal?

No.

Wow,

Hans sounds a lot like Tim Curtin. If it isn't him it's his alter ego.

Hans, answer my previous points. You are wrapped up in quantitative assumptions, whereas you ignore qualitative parameters. A bigger plant is not necessarily more nutritious. We have to better understand the effects of increased C02 on C:N:P ratios in plants, given that the latter two nutrients are often limiting. Animals, especially insects are often nitrogen limited. There is abundant evidence that N will decrease in plant tissues as C is taken up. And of course cnages in C:N:P ratios will affect conentrations of N and C based allelochemicals.

This "C02 is plant food" mantra is therefore rubbish. Basically, this argument was shot to pieces on the Tim Curtin thread and yet here I am again, having to demolish it once again. It ignores a huge number of context and trait dependent parameters. It ignores interactions with the biotic and abiotic environment. Hans, please name me scientists working in the field who claim that we will reduce hunger by pumping more and more C02 into the atmosphere. And I mean scientists with length publication records, especially those who understand consumer-based food webs.

Moreover, plants will acclimitaize to higher levels of C02; in other words biomnass will increase to a certain point in some plants (certainly in many it will not) but then will level off.

And what about you? What are your relevant qualifications in this field?

Jeff Harvey
There are many studies that show that enhanced CO2 promotes both growth and yield.Even when there maybe some loss due to micro-nutrient lack,the overall effect is still
increased productivity.
Wnd Jeff,please get off your high horse about questioning other peoples "qualifications"etc.You do it all the time and it is intellectually childish.

There are many studies that show that enhanced CO2 promotes both growth and yield. Even when there maybe some loss due to micro-nutrient lack,the overall effect is still increased productivity.

So name one that demonstrates CO2 alone enhances useable productivity. Claiming so isn't terribly convincing.

please get off your high horse about questioning other peoples "qualifications"etc.You do it all the time and it is intellectually childish.

Not nearly as embarrassingly childish as those parroting 'CO2 is plant food' just because they heard some wazoo claim it, surely?

Wnd Jeff,please get off your high horse about questioning other peoples "qualifications"etc.You do it all the time and it is intellectually childish.

So says the person *without* qualifications, of course.

"Jeff,please get off your high horse about questioning other peoples "qualifications"etc.You do it all the time and it is intellectually childish.

Posted by: warren"

Nope, he was going on about *Hans'* qualifications.

After all he's merely SAYING that "this is so", but how do we know he has any clue?

Actually, we can answer that: he HAS no clue, but there we go.

As to you, warren, why do you keep going on about the qualifications of those 30,000 scientists against AGW science?

Why do you want NOT to hear from specialists in a field?

If CO2 is the determining factor in plant growth, why is it a common finding that plants grown in high CO2 have fewer stomata on their leaves (e.g. Woodward, 1987; Royer, 2001)?

Name one study...sure!
Vu,Allen,Gesch 2006 Up regulation of photosynthesis and sucrose metabolism enzymes..of sugarcane under elevated growth CO2.Plant Science 171.
dhogaza,I have scientific qualifications,but that is not the point.Jeff Harvey appears to try and lord it over people because of his so-called "expertise".He does it all the time this blog,only ofcourse to the sceptics.He never takes the same line withe believers.It would be preferable if he would use facts and logic to make his mark,rather than some inflated view of his own status.
WOW,the oregon petition had one purpose,and that is to demonstrate that there is no such thing as a consensus,which it amply demonstated.As for specialists in the field,do you mean people like John Christy,Roy Spencer,Richard Lindzen and Willie Soon?Are they some of these "specialists" you refer to?

Wrren, where were those plants raised? And what was the energetic cost of their raising? And what about the lack of predation in their study?

(ignore that the US Corn Belt will NOT like you pushing sugar cane)

You really need to know something about the processes before you can spout off about them as any form of proof.

And, warren, you see Jeff rollin', you hatin'.

"the oregon petition had one purpose,and that is to demonstrate that there is no such thing as a consensus,"

No, it had ONE purpose: propaganda, for which the truth was an irrelevant commodity.

They are all touted as scientists against AGW, therefore the existence of dental hygienists on the list is very much an overstatement of their education on the subject.

As to Roy? When it comes to his faith vs his science training, his faith will win every time.

Soon? Have you read his paper? I don't think you did yourself any favours there.

And the list of publications from Christy and Lindzen is thin indeed, whilst their punditry has never been higher. They are, to use someone else's denigration, scientists who are now playing politicians and, as I pointed out at the time, are no longer scientists plying that trade.

warren said:"Jeff Harvey appears to try and lord it over people because of his so-called "expertise".He does it all the time this blog,only ofcourse to the sceptics.He never takes the same line withe believers."

That is because the "believers" don't make shit up and pretend to be experts, as Hans did. You obviously noticed the profound silence by Hans, and thought you had to fill the void.

The Oregon petition showed that you can collect signatures from technical people without expertise in climate science, who overestimate their level of understanding of science based on their ignorance. You want consensus in a field, you look at how productive ideas are.

The other thing about the Oregon Petition, is that it is worded to fool the naive and gullible. Note that the signers are denying catastrophic global warming, not global warming. Catastrophic level, well that is up to the signer to decide. Is that worst-case scenario? If so, even I could sign it, if not for the fact that I know the purpose of these petitions is to mislead the public.

warren:"As for specialists in the field,do you mean people like John Christy,Roy Spencer,Richard Lindzen and Willie Soon?Are they some of these "specialists" you refer to?"

Wow, what a sad list! Christy and Spencer are the pair, who after being told repeatedly their satellite temperatures were in error, had to have their error found by an outside group.
The Effect of Diurnal Correction on Satellite-Derived Lower Tropospheric Temperature
Carl A. Mears and Frank J. Wentz
Science,
2 September 2005: 1548-1551.

I actually heard Christy bring up the "CO2 lags warming by 800 years" argument in a Q&A a couple of years ago, which is a stupid argument meant to deceive the masses.

Soon was never competent in climate to begin with. "In 2004 Soon was awarded the "Petr Beckmann Award for courage and achievement in the defense of scientific truth" by Doctors for Disaster Preparedness." ROTFL!

Lindzen can't admit he was wrong about the magic negative feedback fairy (infrared iris) saving our bacon.

Warren, the first red flag when searching for that paper is that CO2 'science' has it listed.

The second was that it studied the impact on a single C4 species.

The third was that the growing conditions aren't specified in the abstract.

The fourth is that at double the concentration of atmospheric CO2 we're experiencing currently, I'm not aware of any reliable models detailing the climate impact on weather patterns and hence global food production.

And the fifth is that the impact on wider interdependent biological systems, as explained over and over again in the Curtin threads, are not quantified.

But as you're all too willing to buy the CO2=plant food=net gain sloganising, when the real world impact is not addressed by that paper, perhaps you can address those points yourself.

Jeff asked "Hans, please name me scientists working in the field who claim that we will reduce hunger by pumping more and more C02 into the atmosphere....
Moreover, plants will acclimitaize to higher levels of C02; in other words biomnass will increase to a certain point in some plants (certainly in many it will not) but then will level off."

Jawohl:

Keith Jaggard, Aiming Qi, Eric Ober, "Possible changes to arable crop yields by 2050". Phil.Trans.R.Soc. (2010), 365, 2835-2851.

From the Abstract:

By 2050, the world population is likely to be 9.1 billion, the CO2 concentration 550 ppm, the ozone concentration 60 ppb and the climate warmer by ca 28C. In these conditions, what contribution can increased crop yield make to feeding the world?

CO2 enrichment is likely to increase yields of most crops by approximately 13 per cent but leave yields of C4 crops unchanged. It will tend to reduce water consumption by all crops, but this effect will be approximately cancelled out by the effect of the increased temperature on evaporation rates. In many places increased temperature will provide opportunities to manipulate agronomy to improve crop performance. Ozone concentration increases will decrease yields by 5 per cent or more.

Plant breeders will probably be able to increase yields considerably in the CO2-enriched environment of the future, and most weeds and airborne pests and diseases should remain controllable, so long as policy changes do not remove too many types of crop-protection chemicals. However, soilborne pathogens are likely to be an increasing problem when warmer weather will increase their
multiplication rates; control is likely to need a transgenic approach to breeding for resistance.

There is a large gap between achievable yields and those delivered by farmers, even in the most efficient agricultural systems. A gap is inevitable, but there are large differences between farmers, even between those who have used the same resources. If this gap is closed and accompanied by improvements in potential yields then there is a good prospect that crop production will increase by approximately 50 per cent or more by 2050 without extra land. However, the demands for land to produce bio-energy have not been factored into these calculations.

Anyway, after rudeness in your last, my drink offer is terminated. Wiedersehn

Hans

[Warren](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

If your simplistic characterisation correct, and Jeff's, mine, and others' contradiction thereof is incorrect, then how do you [explain this](http://www.sciencemag.org/cgi/content/abstract/329/5994/940)?

I'll bet that your "[scientific qulaifications](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…)" are not in photosynthetic biochemistry or in ecology, or you would not be nearly so quick to promote the naïve idea of across-the-board linearity between CO2 concentration and primary productivity.

Warren,

What is the actual point you're trying to make?

1. That CO2 enhances plant growth? (Nobody disputes this)

2. That unconstrained increase of CO2 in the atmosphere will result in a net beneficial effect to the autotrophic biosphere? or

3. That unconstrained increase of CO2 in the atmosphere will result in a net positive effect for humankind?

This is unclear from your posts so far.

[Hans](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

It is apparent to any ecologist with an inkling of understanding about biochemistry that even in the abstract that you quote there are a number of unjustifiable assumptions. I'm off to a grant-proposal meeting just now, so I won't addres them immediately, but I think you'll find that one naïve paper guessing about the future does not refute the hard evidence/empirical data of many other studies.

I've twice now linked to Zhao and Running ([Science 20 August 2010: Vol. 329. no. 5994, pp. 940 - 943 DOI:10.1126/science.1192666](http://www.sciencemag.org/cgi/content/abstract/329/5994/940))... You should have a read and consider the implications for your imagined CO2 Utopia, where all negative shiftings are absent.

Your stance shows exactly why a little knowledge is a dangerous thing...

Oh, and Tim Lambert appears to have knocked back my first reply to you, so I will simply note that your premise of a basis for legal action is completely specious. I'll leave it to you to figure out why.

> ...your premise of a basis for legal action is completely specious...

I think that - if there isn't one already - we need a new nomenclature modeled on the well-known meme derived from Godwin's Law: you bring up Hitler/Nazis, you are automatically deemed to have lost the argument.

(Unless of course you're actually arguing about the history surrounding WWII or certain political philosophies...)

The new one would apply to discussions about science: you assert that your opponent's scientific claims constitute a basis for legal action, you lose the argument.

Perhaps someone can come up with a catchy name for it. Unfortunately Monckton, Curtin and Hans all seem to be vying for naming rights.

"Perhaps someone can come up with a catchy name for it."

how about the "Bernard your bridges" gambit?

"Perhaps someone can come up with a catchy name for it."

Strategic Leagal Intimidation To Silence or Chill Criticism (SLIT-SOCC).

Hans:

>*Your anonymity is here no defense against a sub poena to Lambert to reveal, who you are*

Where have I heard this threat before?

[BTW "Hans"](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…)' are you another fool or the [same fool](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) who thinks the time ends in 2050?

"Hans" I double passesd my post above throught google translate to get the effect you are after:

BTW, "Hans" 'Are you thinking another fool or the fool that ends the same time in 2050?

And PS, you forgot to apply Bad English to your last post.

blockquote>And PS, you forgot to apply Bad English to your last post.

His non-"Bad Englished" style is reminiscent of Curtin also.

To use [SLIT-SOCC](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) in context:

"Hans'" resort to threats of legal action is surrender via SLIT-SOCC Law, and shows recognition of "Hans'" inability to argue the science.

.

National Center for Atmospheric Research (NCAR)is getting closer to the truth about the C02 crock.

http://www.tinyurl.com.au/is0

sunspot,

Interesting link, far better than your usual linkspam, and quite relevant if your field job is to keep satellites aloft. I don't see how it relates to climate change though.

Please tell us how the observed decrease in the thermosphere affects the climate, and why the last few years, which have had the lowest recorded solar ultraviolet irradiance, are still among the hottest few on record.

Warren,

Questioning someone's qualifications IS NOT childish. Extraordinary claims require extarordinary proof. You will find very few qualified scientists making the kinds of general statements, assuming linear outcomes, that the likes of Hans and J do. And the fact that you dredged up the comical 'Oregon Petition' tells me that your science ain't much up to scratch, either.

If I was shooting my mouth of about physics or medicine, and had no qualifications in those fields, and my comments were then corrected by researchers who do have qualifications in those fields, then who would be expected to be correct? None of those spouting the nonsense about Co2-primary productivity nonsense (including yourself) know what the hell you are talking about. Sorry to be blunt, but that it the thrust of it. A few controlled experiments in labs or greenhouses do not represent the real world of complex adaptive systems with decidedly non-linear dynamics. We simply cannot ignore the importance of scales, from stochastic processes involving changes in the ecophysiology of plants and their consumers at small scales and emergent processes, such as productivity or resilience occurring at larger scales. Thus far, our understanding of the almost infinite number of processes that regulate the rules governing the assembly and functioning are in their infancy.

None of those spewing the 'C02 is plant food crock' argument on this thread have addressed a single point I have made. Not one. Instead in true contrarian fashion they have highlighted one or two studies but ignored countless others with very different takes. The paper Hans cited above appears to ignore biotic interactions, as if they don't matter. But most scientists know that they do. They also know that a dramatic rise in extreme abiotic conditions under a warming climate will make the predictions of the tidy little models mostly worthless.

In the abstract of the paper Hans cited it states that "most weeds and airborne pests and diseases should remain controllable".

I completely and utterly disagree.

On what empirical evidence? Many saying such things are crossing their fingers and hoping for the tooth fairy. Invasive organisms, many of them plants, cost the global economy billions of dollars every year. This is because they spread rapidly, are resistant to many herbicides, and end up outcompeting native plant assemblages. Far from winning the war with invasives, at the moment we are losing it big time. And with more C02 in the atmosphere early successional r-strategist weeds will become even more of a massive problem, especially in ecologically simple agricultural systems.

Lastly Hans has the audacity to accuse me of being rude, this after saying:

"What only slightly surprises me is that Jeff holds down a post in the very tolerant Netherlands, where they correctly consider that it is cheaper to align him to some whacky institute than to a home for the absurd".

So that isn't rude? If you live in glass houses, Hans, don't throw stones.

WOW,you asked for a study and you got it.If you dont like it,then that is your problem.Here is a couple more for your perusal:
1]CO2 crop growth enhancement and toxicity in wheat and rice.Bugbee,Spanarkel,Johnsen,Monje,Koerner.1994 Utah
2]Genotypic variation in rice yield enhancement by elevated CO2... Shimono,Okada,Yamakawa,Hasegawa.2009
tp hamilton
The oregon petition is something you seem to be quite uninformed about.The are more than 31000 signatories,9,000 of whom are PHD's.Of the sinatories,5,800 are specialists in Physics,3,800 in atmospheric,envirnmental or earth science,and 3000 in Biology.

m fess, you maybe need to get someone, maybe the kid next door, to read it and explain it to you.

Roy Spencer is now admitting the satellite temp data is mostly crap.

http://www.tinyurl.com.au/is9

Hi MFS,to your questions.
1]I am glad we agree that CO2 enhances plant growth,and if that is true then what is the reason for this latest post by Tim Lambert?
2]A net beneficial effect to the biophere?Yes ,that is what the evidence suggests.
3]A net positive effect for humankind?Yes the evidence suggets that a CO2 enriched atmosphere will stimulate plant growth and result in the greening of the planet.

>*I am glad we agree that CO2 enhances plant growth,*

[Firstly warren this claim is only true under certain controlled conditions.]

>*and if that is true then what is the reason for this latest post by Tim Lambert?*

The reason for this video and post is that morons like Monckton, Curtin and warren are blind to all but the positives effects of CO2. Fools continue to deny the net impact of CO2 is not determined by adding the benefits and ignoring the costs. Consistent with this approach denialists fail to cite studies re the impacts of AGW 2050.

Jeff Harvey:Exraordinary claims require extraordinary proof.Yes and personal qualifications are not "proof" when it comes discussions that rely on evidence.Let your facts and logic argue your case and nothing else.
And in regards to your posts,you always put a lot of ideas in them but not a lot of hard data.Remember,science is numbers.You can speculate about the future but you have to have some numbers to give your claims credibility.
You mention "countless" other studies with very different takes'.So go ahead Jeff,you start citing them and I will start counting them.

Jakerman,so far we have no hard data on any negative impact of enhanced CO2 in the atmosphere.There are only theories.

I wonder from under which rock Warren crawled...

Even just mention of the Oregon Petition should bring howls of derisive laughter... the whole OP charade has been so comprehensively debunked hundreds of times, yet Warren seems to think it still hangs on to some shards of credibility. The denialati seem to like making up and disseminating petitions, in a feeble attempt to suggest that many qualified people actually support their nonsense.

As for plant yields, Warren's wafer-thin posts highlight the point I made yesterday: that those pushing the 'C02 is good for primary production' line are linear thinkers, who think that quantity is everything. What about quality per unit of plant biomass? What about the factors that determine plant quality, namely foliar concentrations of primary and secondary metabolites? As I said yesterday, but it evidently has not sunk into Warren's mind, a bigger plant is not necessarily a better plant.

Moreover, what about dramatic changes in concentrations of N and C based allelochemicals, and how these affect plant quality in food chains at small scales and ecological communities and systems at larger scales? To reiterate, Warren, what do you know about population and systems ecology, and the many different processes that determine primary production, community reslience and stability?

What seriously annoys me about these armchair experts who wade in here pushing the contrarian line is that they appear to be quite content with humans to forever tinker and fiddle with the workings of systems whose functioning we barely understand but which sustain us in a huge number of ways through the free delivery of sustaining ecological services, most of which have few, if any, technological substitutes. It takes remarkable hubris, in my opinion, given all of the vast numbers of UNKNOWNS, for anyone, least of all those with no pedigree in related fields, to argue that the current atmospheric experiment that humans are conducting will be beneficial in terms of food production and should be continued.

Note also the hypocrisy of Warren and his like-minded acolytes. They are happy to wave petitions in front of our faces with lists of names they say are qualified scientists arguing that AGW is a myth and that C02 is freat for the planet, but when I, writing as a trained scientist, debunk some of their arguments, they accuse me of being 'intellectually childish' in mentioning my qualifications.

Lastly, Warren writes, "He [maning me] does it all the time this blog,only ofcourse to the sceptics. He never takes the same line withe believers". This statement alone should disqualify Warren from being taken at all seriously. This poitn suggests that the debates over AGW and the effects of C02 are akin to a political argument in which there may be middle ground. But science does not operate that way. My views are based on the vast amount of accumulated empirical evidence, which clearly shows (1) that humans are forcing climate, and (2) that the effects of increasing atmospheric concentrations of C02, in addition to rapid warming, on ecological communities and systems is likely to be deleterious, owing to some of the small scale ecophysiological effects I have already discussed.

Warren, the Oregon petition [detracts from denialist's credibility](http://www.scholarsandrogues.com/2009/08/02/152-oism-scientists-cant-be…), it certainly [doesn't help you](http://greenfyre.wordpress.com/2009/07/12/what-if-the-oregon-petition-n…).

>*Jakerman,so far we have no hard data on any negative impact of enhanced CO2 in the atmosphere.There are only theories.*

Cuts both ways (your blindness is showing again), we've had no hard data on the positives just inference on positives and negatives from the best evidence available.

BTW. I suppose warren would count crop failure due to drought, heat waves, floods has hard data on the negative effect of rising temperature.

Warren probably wouldn't count trials showing the increase in weeds, disease and pests as hard data either.

Warren latest vacuous contribution:

*Remember,science is numbers.You can speculate about the future but you have to have some numbers to give your claims credibility. You mention "countless" other studies with very different takes'.So go ahead Jeff,you start citing them and I will start counting them*.

Arguing with someone who uses this logic is like trying to win a pissing contestmatchanti-environmental response. That is to say, without 100% unequivocal proof, a problem does not exist. This tried-and-trusted contrarian logic has been used to downplay the effects of acid rain, biodiversity loss, various forms of pollution, climate change etc. Now it is Warren's turn. Since our understanding of the processes involved in regulating biodiversity and ecosystem functioning are still quite basic, then there is no reason that humans should do anything to change course. How fast are we extirpating biodiversity through a combination of assaults on natural systems? We do not accurately know, so Warren will say then we should stay the course. Maintain the status quo. A forest ecologist in teh United States once told me that to fully understand the effects of acid rain on forest ecosystems would require billions of dollars - never to be funded. So therefore, without the 100% complete evidence the problem did not not exist. He told me that this was the hub of the contrarian strategy. It is all of nothing. If the story is not utterly complete (and in science it rarely is), then there is no problem.

There is an abundance of literature showing the effects of increased C02 on primary and secondary plant metabolites, but to explore these in natural systems will require hundreds of researchers working on the same system at the same time. Rick Lindroth and Ros Gleadows have worked in the field with mixed results. Most importantly, different plants within the same community may respond quite differently to elevtated C02 regimes, leading to big winners and big losers. The end result is a reduction in local ecological diversity with some plants becoming dominats and may others disappearing altogether. But this is only one potential outcome. Its a crap shoot. And one that is not prident, given all of the unknown processes that may emerge.

> Roy Spencer is now admitting the satellite temp data is mostly crap.

Well, that's a logical response to the implication that the satellite data doesn't support your preconceived position - but it doesn't make it correct.

> Even just mention of the Oregon Petition should bring howls of derisive laughter...

It did from me ;-)

[warren](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…):

> ...personal qualifications are not "proof" when it comes discussions that rely on evidence.

[warren](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…):

> The oregon petition is something you seem to be quite uninformed about.The are more than 31000 signatories,9,000 of whom are PHD's.Of the sinatories,5,800 are specialists in Physics,3,800 in atmospheric,envirnmental or earth science,and 3000 in Biology.

Shorter warren - qualifications matter only when those holding them agree with me.

Bernard J: talk with you about as fruitful as a debate between Martin Luther and bin Laden, with your unconditional acceptance of everything you read when it promotes worldwide alarm like absurd paper of Zhao & Running, and your critical response always lacking in substance, if you read something positive about the prospects of our planet like Jaggard et al.

Jaggardâs fine paper deserves more attention than you have given, but no doubt, Zhao & Running serving your financial grant application better than Jaggard et al, so that is your preference.

Also, you love Zhao & Running Abstract when they say "Terrestrial net primary production (NPP) the amount of atmospheric carbon quantified by plants and accumulated as a solid Biomass. Previous studies have shown that climate constraints were relaxed by increasing temperature and solar radiation, resulting in an upward trend in NPP from 1982 to 1999. In the past decade (2000-2009), the
warmest since instrumental measurements began, should mean continued increases in the NPP, but we estimate a reduction of global NPP of 0.55 petagrams of carbon". Per annum? Not clear.

But their source (1) is Le Quere 2009, which shows increasing NPP since 2000, as do all other sources, eg CDIAC, simply because only about 44% of growing CO2 emissions (at over 3% p.a.) since 2000 remained airborne.

Luckily for you, I have no say in your Grant application,as you have shown a total inability to check your sources.

Schadenfreude.

Lobell et al (2008) Prioritizing Climate Change Adaptation Needs for Food Security in 2030:

>*[The findings suggest](http://news.bbc.co.uk/2/hi/science/nature/7220807.stm) southern Africa could lose more than 30% of its main crop, maize, by 2030. In South Asia losses of many regional staples, such as rice, millet and maize could top 10%, the report says.*

Even in cool climates the net gains even out with a rise of just only 1·0 °C to 1·8 °C in the UK:

>*[the results obtained](http://journals.cambridge.org/action/displayAbstract?fromPage=online&ai…) suggest that the benefits to winter wheat grain yield from CO2 doubling are offset by an increase in mean seasonal temperature of only 1·0 °C to 1·8 °C in the UK.*

[Shaw et al (2002)](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.126.9944&rep=r…) found that with increasing time higher CO2 suppressed growth.

"Hans" you've completely dropped out of charater, do you feel like the fr@ud you are?

Did you finally google "proxy server"?

The [RS found](http://royalsociety.org/General_WF.aspx?pageid=7317&terms=):

>*Growing crops much closer to real conditions has shown that increased levels of carbon dioxide in the atmosphere will have roughly half the beneficial effects that were previously hoped*

And

>*just a few days of hot temperatures can severely reduce the yield of major food crops such as wheat, soyabean, rice and groundnuts, if they [hot days] coincide with the flowering of these crops. These results suggest that there are particular thresholds above which crops become very vulnerable to climate change.*

[Hans Curtin](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

Jakerman has finally [uttered the words](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) I feared to mention myself, lest I provide you with a clue to skirting your ban here, if you were not already so informed.

Your problem is, you dopey nimrod, that although you might hide your ISP, you can't easily disguise your linguistic mannerisms.

Nor can you hide the fact of your ignorance of photosynthetic biochemistry and of ecology, whether you don the mantle of a 1950s-style economist, or a nebulous German character with a Korean girlfriend, who 'translates' with a curious mix of the language caricatures of the casts of Hogan's Heroes and of Batfink.

Try harder duffus.

"WOW,you asked for a study and you got it."

Warren, that study doesn't show that CO2 is a plant food, nor does it show that plants will grow better under a higher CO2 earth atmosphere because it's not being grown under a higher CO2 earth atmosphere.

>Bernard J: talk with you about as fruitful as a debate between Martin Luther and bin Laden, with your unconditional acceptance of everything you read when it promotes worldwide alarm like absurd paper of Zhao & Running, and your critical response always lacking in substance, if you read something positive about the prospects of our planet like Jaggard et al.

Well, of all of Hans' comments, this is certainly the one that sounds eerily the most like Tim Curtin. His grammar and argument construction is almost identical and Hans' problematic English is starting to ring fake.

[sunspot](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…),

Nice dodge, but your lack of answer seems to point more to inability than unwillingness. I really would be very interested to learn what you think is the effect that the changes in the thermosphere are having in the troposphere, where we live.

Brent,

You assume you know a lot... and fail. It's 11 pm in Australia. It's 2 pm where you are in England (can't recall if you have daylight savings). How much does YOUR employer pay YOU to waste time here?

Tim Curtin, @141:
"But their source (1) is Le Quere 2009, which shows increasing NPP since 2000, as do all other sources, eg CDIAC, simply because only about 44% of growing CO2 emissions (at over 3% p.a.) since 2000 remained airborne."

Tim keeps making this howling mistake - he made it over and over in the previous threads.

Terrestrial NPP is only one, of several sinks for CO2. His argument here is that an increasing quantity of CO2 is removed from the atmosphere each year, and therefore terrestrial NPP must be increasing. This argument assumes that either 1. terrestrial NPP is the only relevant sink, or that 2. somehow the summed behavior of all the sinks over time is a perfect proxy for the behavior of this one particular sink over time.

Tim, I'll make it easy for you (once again - pay attention this time).

Observe that A = B + C + D.
Now observe that A is increasing over time, at "3% p.a.".
Does that tell you that B is increasing "at 3% p.a."?

Of course not - but that is precisely the argument that you keep making.

Don't you know anything m fess ?

Couldn't you assimilate the text ?

"The thermosphere, which ranges in altitude from about 55 to more than 300 miles (90 to 500 kilometers), is a rarified layer of gas at the edge of space where the SUN'S RADIATION FIRST MAKES CONTACT WITH EARTH'S ATMOSPHERE."

"This research makes a compelling case for the need to study the coupled sun-Earth system," says Farzad Kamalabadi, program director in NSF's Division of Atmospheric and Geospace Sciences, "and to illustrate the importance of solar influences on our terrestrial environment with both fundamental scientific implications and societal consequences."

m fess, do you know what terrestrial means ?

"Our work demonstrates that the solar cycle not only varies on the typical 11-year time scale, but also can vary from one solar minimum to another," says lead author Stanley Solomon, a scientist at NCAR's High Altitude Observatory. "All solar minima are not equal."

Or solar maxima I might add.

The results showed the thermosphere cooling in 2008 by 41 kelvins, or K (about 74 degrees Fahrenheit) compared to 1996, with just 2 K attributable to the carbon dioxide increase.

"The results also showed the thermosphere's density decreasing by 31 percent, with just 3 percent attributable to carbon dioxide, and closely approximated the 30 percent reduction in density indicated by measurements of satellite drag."

did you notice anything m fess ?

they are telling you that the CO2 fable is falling apart !

solar energy is the dominant factor ! CO2 only has a minor role in GW !

http://www.tinyurl.com.au/is0

low solar energy, time lag, lower SST's,
la nina, freezing cold and wet, brrr

bye bye aGW

"m fess, do you know what terrestrial means ?"

Yes, it means "the ground" from the Latin "terra".

The ground doesn't float in the upper atmosphere.

Well, not unless you're high on drugs.

"solar energy is the dominant factor ! CO2 only has a minor role in GW !"

Hehehehe. What a loon. He things the thermosphere is the entire atmosphere, hydrosphere and lithosphere!

What a farce you are, spots.

It must be tough on a pair of boobs like Brent & Sunspot, with the world being full of stories they'd like to understand but having no way to tell the relevant from the drivel.

You'd like to recommend using Google, but you already know they'd muff that as well and end up being teabagged. Probably at both ends.

warren said:"tp hamilton The oregon petition is something you seem to be quite uninformed about.The are more than 31000 signatories,9,000 of whom are PHD's.Of the sinatories,5,800 are specialists in Physics,3,800 in atmospheric,envirnmental or earth science,and 3000 in Biology."

I received the petition to sign (unsolicited) in the mail a few years back, and filed it appropriately. I made a point about how the petition was deceptively worded, and you have no response. I should also mention how the petition was accompanied by something that was made to resemble a paper from Proceedings of the National Academy of Science (I think that was the journal format being mimicked, can't be sure after all these years). On my point about how almost all the signatories expertise was not in climate science, no response, either. No, you just remind us of your failure. Feel free to do so again, as if nobody can actually scroll up and read these points.

"I have thought for very long time that our sun must be a big effect on the weather"

But it doesn't shine at night, so where's the invisible sun that is warming nights quicker than the daytime?

'course it's only complete morons who cheer spotty on.

PS rather appropriate that 'enry 'ere calls 'imself a donkey...

Curtin is sprung as Hans, then is so stupid that he uses the same [jape in French](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

sunspot,

I could indeed assimilate the text. I wonder if YOU could... Do you know where the thermosphere is?

Can you tell me why you think changes in its density and temperature are important to the temperature of the troposphere (in wich we live). I mean there is a long way between the two, about 40km of stratosphere and mesosphere.

If you're trying to argue that the thermosphere is more affected by solar radiation than by greenhouse gasses you'll have little argument from me. The thermosphere starts approximately 80km above the earth's surface and ends >500km up. It sits well above the troposphere (where we live, and most of the greenhouse effect takes place). Thus the argument that the thermosphere is affected primarily by the sun, rather than CO2, is neither contentious, nor of any relation to the CO2-warming argument.

Henri,

>I have thought for very long time that our sun must be a big effect on the weather.

Well, indeed! When it's sunny the sun warms us up... when it's cloudy it's colder! :)

If you're talking about climate, however... the argument is whether the sun's influence negates the greenhouse effect of CO2.

> "Hans" you've completely dropped out of charater...

To me he sounds like he's dropped almost completely into Tim Curtin's character - including personal and scientific obsessions, persistent howlers, and somewhat idiosyncratic idiom.

Which - if true - would make his pathetic attempt to disguise himself through his "poor English" and "Korean girlfriend" particularly sad.

And would also mean that I [called it](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) back at #94 :-)

Yes, I can confirm that "Hans" is yet another one of Curtin's sockpuppets.

Henri. I, for one, am perfectly happy to accept the possibility of the sun's oscillations affecting our climate.

Just show me that the areas of the earth exposed to more sun for long periods of the year - say, the tropics - are warming faster than areas deprived of sun exposure for long periods of the year - say, the poles. Or perhaps show me that daytime - sun exposed - temperatures are rising faster than nighttime - sun not-there - temperatures.

Perfectly happy. Just show me the maps and the figures, graphs will do - century scale preferably.

"Do people on here accept the possibilty that on century timescale the climate ups and downs may be caused by oscilations in sun?"

Would this be ALL the oscillations, or just part of then, Donkey?

Because part of them is what the IPCC reports, so nobody is going to deny that mechanism on the pro-AGW side. Whether the denial of AGW side will accept merely *part* is another matter: many still think there is no warming at all.

But ALL? No, there is no possibility that all the oscillations in temperature are down to the sun's oscillations. For the simple fact that the sun is in a lull of output, yet the warming continues apace, nearly as quickly as when the sun was at a high level of activity.

Isn't Curtin's antics at sockpuppetry here against the law? It's computer trespass.

Quite a serious crime.

One Brit is even facing terrorism charges and is being extradited over them.

So the charge is quite serious.

Just because you invite someone into your living room doesn't mean they're not trespassing when they wander into your bedroom after being specifically told not to.

German, Korean, French...

How many [sockpuppets of different nationalities will Curtin try](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) before he acknowledges that he is incapable of disguising his mannerisms and his ideologies?

Silly old man.

Jeff Harvey[Your Honourable Expertness]
Jeff,your last 2 posts were good but you still did not give any hard data to back up your claims.You also avoided your chance to verify the "countless studies" assertion,but no matter, for you as a scientist I will provide some more studies that show increased yields from CO2 fertilization.
Jones et al 1984[high CO2 promotes yield in Soyabeans]
Idso 1987[Temperature enhances Co2 fertilization]
Poorter 1993[Over 156 species,a 41% increase for C3 plants,a 22% increase for C4 plants]Many trials were outdoor,field tests.
Allen 1988.CO2 fertilization,[Confirmed that nitrogen content was lower for leaves but not for seeds]This addresses your plant quality objection.
There many more and I will be happy to cite them for you.Your main point seems to be about limitations to the fertilization effect,and it is a valid one.With micro-nutrient stress the CO2 benefit is less,and extreme temperatures totally remove any benefit.However we are talking about very high temps for prolonged periods,which if they occurred would reduce yields in any case.

Henri le Cheval is also a Tim Curtin sock puppet.

*[Post from Brent sockpuppet removed]*

Warren you really are blind to findings that [contradict your beliefs](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

Tim Curtin, you are a silly old man. And quite appropriately you look a complete idiot.

"Wow, why you call me Donkey? Please,a little respect."

You have to earn respect, Donkey. Demanding it doesn't work, it just makes you a wanker.

"Of corse not ALL oscillations! I see corelations between sunspot activity and cool past periods. "

Correlation is not causation, Donkey. What's your causation?

And the IPCC also believe in the same thing. They believe that some of the variations in temperature are explained by the Sun. However, the majority of the variation is explained by the effects of CO2 and other greenhouse gases.

They've done the work, and not based it merely upon their "Opinion" like you do, Donkey.

The sun is responsible for NO MORE THAN 30% of the variation in temperatures in the global historical record. CO2 and other greenhouse gases from human generation are responsible for double that.

And that's not mere "opinion".

"My question again: Do people think this is promising... worth investigating?"

It has been.

Try reading the IPCC reports at

http://www.ipcc.ch

Funny how you're "skeptical" of something you haven't even read. I guess it makes it easier to DENY its conclusions.

TP Hamilton.
The oregon petition was meant to show that the science is not settled and that there is no consensus.It states that on the petition page.I have already posted the numbers in regards to the qualifications of the signatories.However lets look closer.Of the signatories under Atmosphere science,we have
1]Atmospheric 112
2]Climatology 39
3]Meteorology 343
4]Astronomy 59
5]Astrophysics 26
Now in order to anticipate your objections,lets just remind ourselves of the qualifications of a few other people.
Jim Hanson-Astrophysics/Maths
Michael Mann-Maths/Physics/Geology
Gavin Schmidt-Applied Mathematics
Caspar Ammann-Geology
Tim Flannery-ENGLISH !!!!????

"The oregon petition was meant to show that the science is not settled"

How can it do that when it doesn't ask for scientists who know the science involved to answer, when it doesn't explain what science is settled and when it doesn't even care if there are scientists answering?

And what is not settled? There are PhD's in geology who STILL maintain that the earth is 6000 years old and/or flat.

You can find nutcases in every sphere of influence. Especially when there's lots of money to be made in pandering to the desires of big business:

[Lovely Money](http://en.wikipedia.org/wiki/Frederick_Seitz#Consultancy_career)

Sorry my lovely,but a very poor straw man."Lot of money to be made"
Do you mean like when national science academies send their sweethearts on first class holidays to Bali and Copenhagen and Cancun?Is that what you mean?Compare Monckton and Anthony Watts coming to Australia.Financed by government,big oil,the coal industry?No sorry,from private people and from their own pockets.

"Do you mean like when national science academies send their sweethearts on first class holidays to Bali and Copenhagen and Cancun?"

No, I mean like Richard Lindzen getting $2,500 A DAY for consulting.

As opposed to this:

[Paying your own airfare](http://watchingthedeniers.wordpress.com/2010/08/12/myth-of-the-climate-…)

> I will provide some more studies that show increased yields from CO2 fertilization.

Which is a red herring, as has been explained over and over again. Not all plants benefit from CO2 fertilisation, and the **OTHER** effects of pumping CO2 into the atmosphere may more than negate any benefits so obtained.

In other words, pretending that CO2 fertilisation is all that matters is a Curtin-like false accounting trick.

And by "private individuals from their own pockets" you mean like:

[Kich Industries] [http://www.newyorker.com/reporting/2010/08/30/100830fa_fact_mayer]

[and private companies](http://www.opensecrets.org/news/2010/08/pro-environment-groups-were-out…)

like, for example, [this guy](http://www.desmogblog.com/climate-skeptic-pat-michaels-admits-cnn-forty…) who was SO OPEN about his money, that owning up to some of its source becomes news..?

Trying again...

[Koch Industries] (http://www.newyorker.com/reporting/2010/08/30/100830fa_fact_mayer)

[Koch Industries](http://www.newyorker.com/reporting/2010/08/30/100830fa_fact_mayer)

damn "spaces have meaning". Didn't Makefiles teach people ANYTHING???

Warren,

A colleague of mine did his PhD on the subject of plant stoichiometry and effects of interactions with two aphid species. I discussed this with him and he was flabbergasted that anyone with even a basic understanding of plant ecophysiology would try and extrpolate the effects of increases in C02 and somehow argue that nature will beneift from it. The studies that you cite were all conducted under closed conditions in which biotic interactions were excluded. Nature can be appropriately described as a complex adaptive system (Levin, 1999) in which there are links over an infinte number of spatiotemporal scales. But, to reiterate, THESE SYSTEMS ARE INHERENTLY EXCEEDINGLY COMNPLEX AND THE RULES GOVERNING THEIR FUNCTIONING ARR BARELY UNDERSTOOD [emphasis mine].

With no disprespect, it is clear to me that you do not understand basic population, evolutionary or systems ecology. If you did, then yoú'd realize that it is virtually impossible to generate relibale data over the scales of time and space necessary to be able to predict the outcome of the human experiment. This is the cunning strategy that you use to donwplay the inevitable ecological effects - many likely to be highly negative - of pumping more and more C02 into the atmosphere. Your strategy is the same used by those who downplay current extinction rates - that without hard evidence, 'numbers', the problem does not exist. But anyone working on trying to measure extinction rates knows that we have only formally classified about 5% or less of extant species diversity, and much less of genetic diversity. It should be obvious that as humans continue to assault and simplify natural systems, then biodiversity is being lost and fast. But those who argue as you do say, 'without the data, there is no problem'.

It is the same with the issue of C02, plant quality and cascading effects on ecological systems. The effects of this epxeriment will be non-linear: there will be winners and losers. Changes will occur in a comparatively short period of time. And given that these changes will vary from swings in C:N:P ratios to competition in ecological systems, what we do know about cause-and-effect relationships should be enough to stop tinkering with the atmosphere.

Lastly, I find it quite amusing that you write to me in a patronizing manner as if you are a sage of wisdom and as if you have a good grasp of the field. You do not. As I said, you clearly do not understand basic ecology. You are a certain candidate for the Dunning-Kruger affect award. Like it or not, I know much more about the fields of ecophysiology and ecology than you do. This positions me in a far better place to be able to evaluate all of the empirical evidence. Your promotion of the bogus Oregon Petition also undermines any credibility that you might have. It seems to me that you are a right wing libertarian with a bit of superficial knowledge. But not nearly enough.

Now please get lost with your grade-school histrionics. I have science to do.

Hans Henri Curtin.

You've been outed repeatedly; why bother pretending that you haven't been caught with your trousers around your ankles?

At your age it's too late to try to grow up, but perhaps you might consider growing a shred or two of dignity.

And warren, you might like to seriously consider the recent paper by Zhao and Running ([Science 20 August 2010: Vol. 329. no. 5994, pp. 940 - 943 DOI:10.1126/science.1192666](http://www.sciencemag.org/cgi/content/abstract/329/5994/940)), to which I have linked several times on this thread already. It seems to have caught in the craw of some of the manifestations of Curtin on this thread, so the authors must have a significant point...

CO2 just isn't doing what you seem to be expecting it to do, for exactly some of the reasons that Jeff, I, jakerman, MFS, lee, and others have been trying to explain to you. It a bit of a problem for your claim that the last decade of empirical data vehemently contradicts it.

Tim Curtin, you must be the saddest and most desperate attention seeker on the whole intertubes.

Can't you even manage to scrape together the tiny shred of self-respect and insight that would make you so embarrassed by your behaviour that you never showed your face here again?

"Where do you got your 30% number from?"

The IPCC reports, Donkey. You know, that report you don't believe without ever having read it.

If you have a different figure, then go ahead, knock yourself out.

PS you tried the "I is not a speaking of the english" before, Tim^WHans^WDonkey.

Didn't work then.

Lotharsen,what "other effects" are you talking about?Are they demonstrable?

Bernard Buddy,the Zhao/Running study was about the effect of drought,not CO2.If you are trying to say that water availability is a more important factor in determining plant growth than CO2,then you are right.Drought is cyclical,but an increase in CO2 will give greater yields to a majority of species over the long term.
Cuelemans/Mosseau 1994.Effects of elevated CO2 on woody plants.
Johnson,Ball,Walker 1997.Effects of CO2 and nitrogen fertilization on vegetation and soil nutrient content.
Moreover,a change in yield due to CO2 over 9 years,[a 6% increase]would not be measurable in statistically reliable terms.

Millions of years ago when there was 20xCO2 in the atmosphere the plants and animals were the BIGGEST in the history of Earth.

Bigger than the Giant Sequoia?

Some of the animals were big, but the plants were not notably bigger than today.

Actually, bigger animals would only be possible in an atmosphere with greater amounts of OXYGEN, not carbon dioxide.

The higher atmospheric CO2 may have actually increased the carbon:nitrogen ratio in the plants (ie making them less nutritious). This meant that herbivores had to eat more plant material to get the nitrogen they needed. This left them with more carbon, which they could deal with by either increasing their metabolism (essentially becoming warm blooded) to burn it off, or by storing it somewhere and growing bigger.

Jeff Harvey:You know something Jeff,I am starting to seriously doubt your scientific credability.You certainly dont talk like an objective scientist.You sound much more like an ideologically driven activist.I say that because you almost never put real data in your posts,you never answer points directly,and you go on and on with a whole lot of philosphical flim flam.Get scientific man!
Now to the issues in your post.In the first paragraph you say,"these systems...are barely understood".If that is true Jeff then how can you say with such certainty that increased CO2 will be detrimental to the biosphere??
In the second paragraph you say,it is virtually impossible to generate reliable data...to predict the outcome of the human experiment".But you yourself have opined at length about what you believe the outcomes will be.A contradiction is it not?
Just as a matter of interest Jeff,what are your scientific qualifications?

NOAA: Russian Heat Wave Not Due to âGlobal Warmingâ

NOAA on the 2010 Russian Heat Wave (excerpt):

Despite this strong evidence for a warming planet, greenhouse gas forcing fails to explain the 2010 heat wave over western Russia. The natural process of atmospheric blocking, and the climate impacts induced by such blocking, are the principal cause for this heat wave.

However, the temperature would have been cooler if global warming hadn't also been underway.

"Lotharsen,what "other effects" are you talking about?Are they demonstrable?

Posted by: warren"

He's talking about the enhanced greenhouse effect that results from extra CO2, warren.

WOW,I thought that might have been what he was talking about.Now to the second part of my question.Can it bne demonstrated that the enhanced greenhouse effect that we have observed is due to CO2?It should cause some warming,but how much?

Yes, it can.

Satellite observations show that the brightness of the earth in CO2 absorption wavelengths has reduced.

Satellite images also show that the radiation at the top of the atmosphere is out of balance to the tune of about 9W/m^2.

I should cause something around 3C of warming per doubling when equilibrium is reached.

WOW,the first 2 facts are correct.The third statement is speculation.We still dont know how much of the warming that we have observed is due to CO2.

No, the third statement is also fact.

It will be around 3C per doubling.

PS if you knew already that CO2's effects could be proven, why the hell did you ask?

The warming effect of CO2 can been seen in the laboratory,but we dont know how it affects the atmosphere of the real world.We just dont know how much warming it causes.
So if 3C for a doubling is a fact can you direct me to the paper the proves it to be so?Remember,it has to be a "fact".

> Just as a matter of interest Jeff,what are your scientific qualifications?

If you really want to know Jeff's qualifications, you could always google him. Just as a matter of interest Warren, what are **your** scientific qualifications?

Oh actually, I take it back.

I'm not interested. Because, despite whatever qualifications you might decide to invent, inflate or otherwise supply in response, based on your comments in this thread you are clearly a net negative contributor to the sum of human knowledge.

DAVE H,I dont mind telling you my qualifications.I have a diploma in medical laboratory science.That is all.Does that "qualify" me to take part in the discussion?

Dave, I think warren is a dental hygienist.

As to this tooth-polishers backpedaling:

"The warming effect of CO2 can been seen in the laboratory"

How many labs can you fit in polar orbiting satellites in, Warren?

The warming effect is seen IN THE ACTUAL WORLD.

"So if 3C for a doubling is a fact can you direct me to the paper the proves it to be so?"

Have a look here:

http://www.ipcc.ch

and follow the references to the relevant publications.

Google it too if you like. Use Google Scholar.

And while you're at it, maybe you can show us all the papers that prove that the plantlife on earth grow more abundantly under doubled CO2.

Cheers.

Warren,

You the one raising the issue of qualifications, so it is hypocritical and absurd that you should play the victim as if you are somehow being "excluded" on that basis.

My own qualifications are as irrelevant to this topic as your own. As a result I try to be exceedingly humble around people that do actually know what they are talking about in some considerable detail.

You on the other hand choose to talk down to them in an arrogant, and condescending manner. I find that baffling.

DaveH,No I am not the one raising the issue of qualifications.Jeff Harvey is.He tries to suggest that his argument carries more weight because he is so "qualified".I consider facts and logic to be more valid.What do you think?
I have now looked at Jeff's qualifications and they are very impressive.

"No I am not the one raising the issue of qualifications"

Wow. What a short memory you have (all the better to deny AGW with, I suppose).

[warren whinges about qualifications](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…)

And I'm still waiting for a paper that shows the plants are be better off when we reach double pre-industrial CO2 concentrations. One will do.

Warren,

Jeff's comments about qualifications were directed at one of Tim urtin's many sockpuppets on this thread, who had claimed Jeff did not know how photosynthesis works. If you know who Jeff is, you know that this is absurd and offensive. Jeff's qualifications demonstrate this, and therefore it is entirely relevant to question the authority from which this statement (and others like it) were made, given that they were mere assertions. Curtin's assertions did not have a factual or logical basis.

You OTOH have attacked Jeff for mentioning qualifications, have directly asked him what his are and questioned his scientific credibility. To then go on to make the implication that you are being harassed for being unqualified to comment on this thread is just unreasonable.

You also countered Bernard's citation of a recent study with two older ones and a claim that he was citing a paper in error (ie it referenced drought and not CO2). Now, I don't know if you're read the entire paper, but your riposte could easily be gleaned just from a perusal of the abstract. I haven't read the article, given that it is paywalled, and I am in no way qualified to comment on it - in such a situation I would be forced to rely on the expert opinion of someone such as Bernard who *is* actually experienced enough to understand the nuances of the full paper and its implications. I would be hesitant to contradict the opinion of someone thus qualified, and rather than being rude and dismissive I would be extremely polite in doing so, cognisant of the fact that I was well out of my depth but knowing that even if I was wrong, I might learn something.

That said, my initial thought based solely on the abstract is that it seems sensible to me that CO2-induced warming will lead to more drought, and that drought has a far greater negative impact on plant ecosystems than any notional benefits of CO2 fertilisation. This is without even going into the studies that highlight important species becoming less nutritious (and thus less beneficial to us) in a CO2-rich environment, or becoming more attractive (and thus more susceptible) to their pests.

So what do we have in this thread? On the one hand, we have a number of people well placed to understand the complexities of what impact a rise in CO2 is most likely to have on extremely complex and interdependent ecologies. On the other, causing most of the noise, we have a deluded fantasist using sockpuppets to agree with himself and making simplistic and absurd statments.

And then we have you, referencing the laughable Oregon petition, casting aspersions about financial interests, and then bemoaning the supposed dearth of facts and logic.

Forgive me if - speaking as a layman - I find your position wholly unconvincing.

Warren writes:

>*I have a diploma in medical laboratory science.That is all.Does that "qualify" me to take part in the discussion?*

What disqualifies Warren from credibility is making unsupported claims like this:

>*Drought is cyclical,but an increase in CO2 will give greater yields to a majority of species over the long term.*

Competent scientist have done serious work to compare the net effect of AGW and CO2 increases. The evidence I've already linked you to shows terrible net crop impact in large parts of Africa and Asia, pre 2050. The 2007 IPPC assessment finds globally a net negative crop impact by 2100 and into the future.

Jakerman:Projections and model simulations about what may happen in the future are not evidence.Evidence is Data.The data we have so far shows that both in controlled laboratory situations and field trials that elevated CO2 gives a net benefit to plant growth for a large number of species.The Monash Uni/Gleadow study on cassava is an example of where elevated CO2 results in loss of yield apparently.However given that other studies of CO2 on roots and tubers have shown yield gains[Miglietta1998,Sicher and Bunce1999,Giang/Tanaka],it would be good to see those results replicated before it is taken as gospel.There are also some questions marks over the politics of the Monash/Gleadow study as it was sponsored by the Finkel Foundation which produces the left-wing enviro magazine "G".

> Jeff's comments about qualifications were directed at one of Tim [C]urtin's many sockpuppets on this thread,... If you know who Jeff is, you know that this is absurd and offensive.

And if you know Tim Curtin, you know this is part of his modus operandi - perhaps used in an attempt to distract and derail the discussion when TC's talking points are being thoroughly shredded by evidence and logic.

> Lotharsen,what "other effects" are you talking about?Are they demonstrable?

I addressed [one set](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) earlier, followed by a [second set](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) where I pointed claimants to the Tim Curtin thread which has dealt with these issues, followed by a [link to that thread](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…). (Those responses may have been before you arrived on the thread though.)

And here's another effect that must be taken into account:

> ...it seems sensible to me that CO2-induced warming will lead to more drought, and that drought has a far greater negative impact on plant ecosystems than any notional benefits of CO2 fertilisation...

On a similar note, only a few hours or days of excessive heat during flowering can dramatically reduce yields of certain crops - and if global warming takes place these events will occur more and more often. (Papers discussing this are linked on the Tim Curtin thread.) There are also issues like geographical migration of climatic zones - which unfortunately don't take the land with them, and significant benefits from global warming to predators (whether insect, animal, plant, fungus, bacteria). No doubt there are still others, and it would be foolish to pretend they will not occur.

I seriously recommend you take your time and read through that Tim Curtin thread, perhaps skipping the parts not related to "CO2 is great for agriculture" if they don't also interest you. The claim that more atmospheric CO2 can only be good (for human agriculture) is a key tenet of TC's belief system, and is largely based on extrapolating the kinds of positive effects you cite in studies on the assumption of no corresponding negatives - and that case is addressed in any number of ways on that thread. It would be smart to get through that argument first to determine which claims of that nature may still have merit and which do not.

"The data we have so far shows that both in controlled laboratory situations and field trials that elevated CO2 gives a net benefit to plant growth for a large number of species."

No we don't.

We have lab situations which you refuse to accept as proof of CO2's effects, so that goes by the wayside.

And we have field trials that show that elevated CO2 gives a net reduction in the nutritional benefit of foodstocks and, in the case of corn, a reduction in the pest repellent properties the corn stock produces, increasing their predation.

We also know that drought weather kills off plants and that flooding causes plant death.

Just look at the Sahel and Bangladesh.

>*Projections and model simulations about what may happen in the future are not evidence.Evidence is Data.The data we have so far shows that both in controlled laboratory situations and field trials that elevated CO2 gives a net benefit to plant growth for a large number of species.*

First point Warrens is under what conditions? Next point, What species?

I have already linked you to [data from trials](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) that show [CO2 can retard growth](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…). The range of data I linked includes field trials studying multiple relevant influences. Data obtained from trials that assess temperature effects and CO2 effects.

I have already pointed out that competent scientist have assessed the evidence to make determinations (such as the AR4). You have not assessed the evidence. You simply cherry pick findings that suit your purpose. Then make unsupported claims on an issue that issue vital to the lives of hundreds of millions of people.

Warren, your blind bias is [once again](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) overwhelming you.

WOW,first off which lab situations are ones that I am denying?I would like to discuss them.
Second,as far as a net reduction in nutritional value is concerned,I dont know of many sudies that have found this.The majority of studies that I know of point the opposite way.However I am willing look at any examples you have.One trend I have observed in these studies is that in c3 plants,Nitrogen concentration is reduced in the in the biomass.However this has to be balanced against the increase in biomass due to CO2 fertilization.So,for example,in studies on wheat with elevated CO2,there have been various results between 25% to 35% increase in biomass in FACE trials.Lets use the 30% figure for the purpose of the discussion[also not without caveats].So for every given weight achieved at ambient CO2 you would get 30% more for a doubling[roughly].So 1kg in ambient would be 1.3kg at doubling.But,as has been pointed out,many studies have shown a decrease in protein concentration,somtimes as high as 15%.So with increased biomass do we have a net benefit in terms of protein production?If the protein concetration in ambient grain is X,then X times .85 will give us the protein concentration[Xi]in the elevated CO2 grain.Xi times 1.3 will give the protein weight[P].If X is 1,then we solve for [P]and get 1.105kg.This therefore is a 10% net benefit from CO2 fertilization.Futher,some tubers such as potaoes show much less loss in protein concentration,so elevated CO2 has a much greater benefit in those cases.

Jakerman,the Shaw et al 2002 trial was a multi-factor trial,and it was mainly for the effect of increased warming,not CO2.Note the infra-red heater.This is not good evidence about CO2 alone.

Warren writes:

>*Jakerman,the Shaw et al 2002 trial was a multi-factor trial,and it was mainly for the effect of increased warming,not CO2.*

I understand that I have given you too much credit. It was a [multi factor trial](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) comparing the effect of elevated CO2 in combination with other factors. Look at every single chart in the results.

>*Note the infra-red heater.This is not good evidence about CO2 alone.*

You along with other denialist are the only fools interesting in the effects of CO2 alone. That is [your blindness](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) that I have pointed to [several times](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

Jakerman,temperature does have an effect.As far as my reading takes me the initial effect of warming is positive for plant growth.At high temps however,the effect is negative,but this is due mainly to the creation of drought-like effects.In other words CO2 does not cause the loss of yield,water stress does.Now if elevated CO2 causes both higher temps AND lower precipitation,then yes the CO2 fertilization effect would be negated.But this is the crux of the debate.IE Whether or not elevated CO2 in the Earth's atmosphere will do both of these things.You probably believe it will.I as a sceptic dont believe it will.In my view a more likely scenario in a warmer world is for an increase in precipitation which in turn will drive higher agricultural yields,water generally being the number one limiting factor on dry land farming.

Warren,

I really do not want to spend too much more time to spend on this topic, except to say that most of the scientific community would adamently disagree with the simple, linear notion that increasing the concentration of atmsopheric C02 will yeild benefits to humanity. In fact, most would say quite the opposite, because scientists know that it is impossible to extrapolate the effects of simple experiments carried out under controlled conditions in laboratories in natural systems which are billions of times more complex.

This is one of the major drawbacks of ecologists - that is, trying to untangle stupendous ecological complexity. Most of us are forced to break these systems down into managable 'parts' that can be studied. This means excluding literally trillions of interactions involving billions of organisms and tens of thousands of species and their interplay with each other and both the biotic and the abiotic environment.

I had PhD student a few years ago who studied multitrophic interactions involving soil insects and above-ground insects as mediated through the same plant species. Her work involved exploring changes in primary and secondary plant metabolites in response to indirect effects caused by organisms in the opposte 'compartment'. We found that soil and above-ground biota do indeed interact, and that herbivore-induced damage of root or shoot tissues did lead to significant changes in concentrations of N-based phytotoxins in other parts of the plant, and these affected insect performance. Volatile profiles, also induced by herbivory, also were affected, leading to changes in the attractiveness of the plants to herbivores and their natural enemies.

Bear in mind that we conducted these experiments under controlled conditions in greenhouses or in tents. Also note that, because the experiments went up to the 4th trophic level, that we had to stick with insects involved in a linear chain, excluding direct and indirect interactions both vertically and horizontally with other organisms in the neighboring soil and plant community. Yet we still had colleagues telling us how 'complicated' these experiments must have been to set up and perform. They were indeed, but nothing close to the complexity in the field, which I have alluded to above.

What I am trying to say is that, because the biosphere is made up of complex adaptive systems, and that processes occurring at very different scales and levels of organization are connected, we also know that fiddling with or altering one small component at one end of the scale continuum can reveberate through the system and dramatically affect other processes at different scales.
For example this may occur because of the introduction of a sinle, non-native species into a new ecosystem where it has no evolutionary history, or because of a change in some key paramater like soil chemistry which might lead to dramatic changes in the composition of the soil community. These changes may in turn lead to quite profound shifts in the dynamics of the system which are non-linear and were impossible to predict at the outset.

The current human experiment on the atmosphere is such a process that will certainly lead to quite significant changes in local (stochastic) and systemic (deteministic) processes but which are difficult if not impossible to predict now. This is because not all plants will respond the same wy to extra C02: some will continue to produce more biomass whereas others may initially but will then quickly acclimatize and level off. Plants with N-based defense chemisty will almost certainly allocate the extra C to growth whilst reducing foliar levels of N, thus reducing concentrations of N-based allelochemicals. Plants with C-based defense chemistry are now known to be reducing foliar levels of primary metabolites (nutrients) whilst increasing investment to higher levels of C-Based foliar toxins. This means that herbivores will have to ingest more plant biomass to accrue the same nutrient levels as previously but at the same time they will be ingesting more plant toxins. This is not in the realm of fiction but of fact.

Moreover, given the rate of change, we can expect to see plants benefitting form extra C02 outcompeting those which do not benefit, or benfit less. What if they are occurring in the same local ecosystem? What will happen is that plants adapted to higher C02 regimes will competitively displace those that are not. This is simple logic. And what will happen to consumers including herbivores and their natural enemies? For most organisms, nitrogen is limiting. Many plants already store more than enough carbon and this explains why plants are, on the whole, nutritionally sub-optimal food for most herbivores. At present, there is profound concern over phosphorus shortage in terrestrial ecosystems, and again, this problem will not be solved by increasingly carbonizing the atmosphere.

Given the time, I would have been happy to discuss the effects of increased atmospheric C02 levels on changes in foliar concentrations of phenolics, proteinase inhibitors, as well as on phylogenetically conserved allelochemicals including glucosinolates, furanocoumarins, pyrollizindine alkalods, iridoid glycosides, cardiac glycosides, flavenoids etc., but as far as I know little research has been done in these areas because there are just too few scientists working on it. Fewer still are explicitly studying trophic interactions, top-down and bottom-up effects in terrestrial food webs and ecosystem dynamics in response to the human experiment on the atmosphere. Partly this is because, as I said earlier, that we will never be able to accurately predict the effects until it is too late and the data are 'all in', owing to the stupendous complexity in nature.

Against this background are a very small number of people, mostly non-biologists, spewing out nonsense on the benefits of increasing carbon-dioxide levels in the atmosphere. These people rely on a a few studies, done in greenhouses, as I have explained, but they go silent when scientists such as myself even mention the words 'complexity' or 'non-linear'. Like you, Warren, they use the strategy that without 100% unequivocal evidence there is no problem. (I suspect you jumped onto this C02 is good bandwagton after reading rhe appalling and simplistic article by Robinson et al. that accompanied the original 'Oregon Petition'.) I find it utterly remarkable that these people say what they do on the basis of all of the vast numbers of unknowns that govern the functioning of communities and ecosystems. This is exactly why most of those pushing the 'C02 is plant food' line are on the academic fringe. Go to just about any conference attended by people working with plants in their research and they will dismiss this argument as being 'loony'.

Today we could not have predicted what the destruction of the tall-grass prairies in the 19th and early 20th centuries would have had on the functioning on ecosystems in western North America. We would have been hard pressed to understand how the loss of desert grasses in New Mexico and Arizona would have been irreversible. We would have been hard pressed to understand the connection between heart-rot fungus in coniferous trees and hummingbird populations in the Rocky Mountain States (there is a connection if one looks through a number of links). We would have realized that it was impossible to predict the effects of extirpating top-level predators such as gray wolves and mountain lions on the dynamics of songbird populations in eastern North America (there is also a link if we look for it). Only in recent years has the term 'extinction debt' come into the ecological vocabulary, whereby we realize that changes inflicted on a system can take decades or centuries to manifest themselves on the stability and resiliencde of the system.

There will no doubt be small and large-scale effects of further carbonizing of the atmosphere. Many are impossible to predict now but will be manifested down the road. It takes remarkable arrogance, in my opinion, for anyone to claim that humans can manage systems whose functioning we barely understand but which sustain us in a myriad of ways, by forver tinkering with chemical and biological propeties in these systems. Its a game of Russian roulette, and one I think that it is wide not to play, given what is at stake.

I will leave it there.

Warren writes:

>*As far as my reading takes me the initial effect of warming is positive for plant growth.*

I've already linked you to evidence that warming is negative already in large parts of Africa, Asia etc. You just don't care to accept that.

>*At high temps however,the effect is negative,but this is due mainly to the creation of drought-like effects.In other words CO2 does not cause the loss of yield,water stress does.*

Go read Shaw again, you missed their findings that higher CO2 can retard growth in a warming world.

>*Now if elevated CO2 causes both higher temps AND lower precipitation,then yes the CO2 fertilization effect would be negated.But this is the crux of the debate.*

Show me where any competent persons serious doubts this. CO2 forces higher temperatures, higher temperature produce higher evaporation, and higher total atmospheric moisture and content hence more water held away from crop use ([ie drought](http://gcmd.nasa.gov/records/GCMD_IPCC_PDSI_1900-2002.html)). Hand in hand with more damaging heavy rains when the cycle dumps out.

>*IE Whether or not elevated CO2 in the Earth's atmosphere will do both of these things.You probably believe it will.I as a sceptic dont believe it will.*

You are not a skeptic. You just ignore evidence that conflicts with your beliefs. Its called denial.

Jeff Harvey;Good to see you back.To be honest,I actually enjoyed reading your latest post.Very informative.You did however,slip up just once.It was the 9th paragraph I think,the one that starts with "Against this background...".Everything else was spot on and I agree it.
Unfortunately however I must take issue with para 9,and its obvious non-facts.
1]"very small number of people,mostly non-biologists..".Absolute rubbish Jeff and we both know it,and you know I can prove you wrong.
2]"a few studies done in greenhouses..".More rubbish Jeff,you know that that is BS.There are studies done for decades,and many field trials including FACE experiments.
3]"strategy that without 100% unequivocal evidence...".A grand exageration Jeff,I have never taken that position.I look at the balance of evidence.
PS I googled your qualifications,they are impecable.

Warren writes:

>*I look at the balance of evidence.*

That's demonstrably false, just read back though this thread for examples of blatant cherry picking and turning away from multi-variable studies that conflicted with Warren's beliefs.

Warren,

Are you a biologist? What are your credentials if you claim that more than a few biologists are spewing our the "C02 will nourish nature and humanity" line? Damn it man, I work with plants, and I go to the conferences where issues like this are debated and argued! And you would be hard pressed to scrape up anybody worth his or her PhD in ecology who would confidently assert that higher C02 concentrations are a good thing. We bloody well do not know enough!!!!!

So go ahead, please point out to me any population or systems ecologist - just one - who has (1) argued that pumping C02 into the atmosphere will be positive, on balance, for nature, and (2) that we have a good enough understanding of what the likely effects will be.

Over the past 30 years a number of eminent scientists - David Tilman, Shaeed Naeem, Kevin McCann, John Huston, Philip Grime, David Wardle, Simon Levin, Steve Pacala, Michel Loreau - and a number of others in the field, have been debating the important issue of the relationship between biodiversity and ecosystem functioning. The issue has generated two schools of thought, the 'rivet-popper' hypotheses and the 'triage' hypothesis. Both camps have their disciples. In other words, there is still broad disagreement amongst experts in spite of the enormous efforts expended since the 1970s to distangle the importance of biodiversity in maintaining healthy and viable ecosystems.

We know much less about the likely outcomes of increasing atmospheric concentrations of C02, and won't know until the data are virtually all in. As I said last time, by then it will too late if things go wrong. You ought to write to one of the leading ecologists working in this highly complex field, Rick Lindroth at University of Wisconsin, and ask him what he thinks. It is his area of expertise. But I can tell you that any scientist who claims that they know that pumping more and more C02 into the air is a good thing are in my opinion speaking out of their butts.

I have some advice for you, Warren: you have lost this debate because you cannot fill in the immense number of gaps. You think that putting one or two pieces into a 100,000 piece jigsaw puzzle is enough. I got news for you pal: it ain't. Very few readers of this thread - aside from ther usual suspects - will swallow your line.

You claim to have looked at the balance of evidence, but IMHO you have a pre-determined worldview. Very little evidence is on on the effects of C02 enhancement on interaction network webs and ecological communities. Some of the data that are in - showing compensatory feeding in insect herbivores under elevated C02 regimes and changes in C:N:P ratios in plants, as well as in C-based allelochemistry, are very worrying. For the millionth time, we do not know enough about the broader effects on non-linear ecological processes to be able to conclude one way or the other. But given the rate of change, and the complex response of species and individuals at local scales, we can expect some food webs to unravel and for many ecosystems to become simplified as the asymetrical effects of increasing C02 become manifest.

That is all I am going to say. There are too many unknowns at present. Now Warren, get a life. It's over.

Abstract from one of the FACE studies by Nowak et al. (2003). Emphasis in italics is mine:

In addition, most herbaceous species had reduced leaf nitrogen (N)-content under elevated [CO2] and
thus only a modest enhancement of A net, whereas most woody species had little change in leaf N with elevated [CO
2] but a larger enhancement of A net. *Early predictions for primary production are more mixed. Predictions that enhancement of productivity would be greater in drier ecosystems or in drier years has only limited support*. Furthermore, differences in productivity enhancements among six plant functional types were not significant. By contrast, increases in productivity enhancements with increased N availability are well supported by the FACE results. *Thus, neither a resource-based conceptual model nor a plant functional type conceptual model is exclusively supported by FACE results, but rather both species identity and resource availability are important factors influencing the response of ecosystems to elevated [CO2]*.

The most important point is that the researchers found the effects of increased C02 on plants to be association-specific. Just as I said in an ealier post. This leads to the point that I have been making earlier: that non-linear association-specific responses will be amplified as one increases the spatial and temporal scales.

I would also like Warren to link for me any study he can find that has examined the effects of increased C02 on (1) food webs up to the third trophic level, inlcuding both the nutritional ecology and behavior of consumers, and on theri population dynamics, and (2) that has explictly examined the effects of increased C02 on longer term ecosystem functioning.

A: Its simple. He can't. As I said before, we do not know nearly enough.

J

Partial abstract from Norby and Luo, New Phytologist, 2004:

*There is a wealth of information on plant responses to CO2 and temperature, but there have been few ecosystem-scale experiments investigating the combined or interactive effects of CO2 enrichment and warming. Factorial experiments to investigate interactions can be difficult to design, conduct, and interpret, and their results may not support predictions at the ecosystem scale â in the context of global change they will always be case studies*

Bingo. Again, such experiments would need billions of dollars - never to be funded. So we are left with small-scale studies that mostly or wholly exclude food webs in which consumers play a major role in regulating plant biomass.

As I said before: WE DO NOT KNOW NEARLY ENOUGH. Humanity is gambling with the future on a large scale.

"WOW,first off which lab situations are ones that I am denying?"

These ones:

"197

The warming effect of CO2 can been seen in the laboratory,but we dont know how it affects the atmosphere of the real world."

You seem blind to evidence of your lies as well as blind to anyone else's evidence if you don't like it.

But this is just another example of your denial. You accept any lab trial or paper or model or hand-wave that supports your NEED to do nothing about AGW for your personal short term gain and REFUSE any similar study that shows up your need to ignore the short term for your own long term self-interest.

Denialist, thy name is thee.

"Second,as far as a net reduction in nutritional value is concerned,I dont know of many sudies that have found this"

Funny. Jeff for example has shown many.

Guess there's none so blind as a denialist in defeat...

"The majority of studies that I know of point the opposite way."

Because you refuse to hear any that don't. Selection bias to the MAXXX!

Warren @213

As far as my reading takes me the initial effect of warming is positive for plant growth.At high temps however,the effect is negative,but this is due mainly to the creation of drought-like effects.In other words CO2 does not cause the loss of yield,water stress does.Now if elevated CO2 causes both higher temps AND lower precipitation,then yes the CO2 fertilization effect would be negated.

You seem to be under the impression that, if temperatures rise, plants will only be under water stress if there is reduced water in the soil. This is not so.

If you have spent any time working in a greenhouse you will know that as temperatures get into the 30s there are plants that will wilt even if the soil is completely sodden. The plants' plumbing just can't move the water fast enough.

In addition, when water is taken up it includes dissolved minerals such as calcium, sodium and potassium. When the water evaporates from the leaves, what do you think happens to the minerals? What is the impact of this?

warren doesn't understand how to show a consensus in a scientific field:"

TP Hamilton. The oregon petition was meant to show that the science is not settled and that there is no consensus.It states that on the petition page."

What it shows is that people like you are duped and completely clueless on what consensus means much less how it is established.

Consensus is when all the experts (people who publish climate science papers) agree. Not when somebody decides themselves qualified to evaluate a scientific sounding statement with the weasel word catastrophic, and the merit of something that is deceptively printed to look like a paper from a journal, who then signs a petition, making it meaningless by their very participation!

warren:"I have already posted the numbers in regards to the qualifications of the signatories.However lets look closer.Of the signatories under Atmosphere science,we have 1]Atmospheric 112"

What is their publication record in climate science? You don't know, and don't care if they have the expertise to evaluate it. This has in fact been done, and the figure is 97% to 3%.

"2]Climatology 39 3]Meteorology 343 4]Astronomy 59 5]Astrophysics 26 Now in order to anticipate your objections,lets just remind ourselves of the qualifications of a few other people.

Jim Hanson-Astrophysics/Maths Michael Mann-Maths/Physics/Geology Gavin Schmidt-Applied Mathematics Caspar Ammann-Geology Tim Flannery-ENGLISH !!!!????"

A self contradicting argument. Mentioning the "qualified" signers of the petition based on their fields, then casting aspersions on actual climate scientists whose degrees are in those very same fields.

What matters is what they have done research and published in. You claim to say it is all about the facts and logic, but your very argument is the opposite.

The field is very interdisciplinary: there are folks with math expertise, computer programming expertise, biology, atmospheric chemistry, fluid dynamics, radiation physics, geology etc. That does not mean that all people with these areas of expertise know how they have been applied to study of climate, folks who could be fooled into signing a petition.

Good place to put these links on the threat to the food chain.

Marine Phytoplankton Declining: Striking Global Changes at the Base of the Marine Food Web Linked to Rising Ocean Temperatures

Acidifying Oceans Spell Bleak Marine Biological Future 'by End of Century', Mediterranean Research Finds

Oceans in Peril: Primed for Mass Extinction?

Ocean Acidification Threatens Food Webs, 150 Scientists Warn

Acid Oceans Threatening Marine Food Chain, Experts Warn

The 800 lb. Gorilla in the Ocean

Scientists warn of global warming threat to marine food chain

Coral doctor sounds the alarm about more acidic seas

Almost makes the whole debate over climate sensitivity seem like a bust up between siblings over who has to wash the dishes.

Warren.

For someone who claims that he follows science, and by implication, the scientific literature, you seem to be blind to the work that contradicts your repeated pronouncements that CO2 is beneficial at ever-increasing concentrations. On this matter Jeff has repeatedly pulled the wings from your fly, and yet you go from querying his credentials, to accepting them and still telling him that he is wrong whilst you are correct.

As others have said, this conversation has been had ad nausuem on Tim Curtin's threads. A number of us in addition to Jeff have referred to work explaining the complexities, but it seems to be invisible to those such as yourself and Tim Curtin. Well, guess what? It won't be invisible to the planet over time.

It's a shame that you can't get behind the paywall to understand the implications of the [Zhao and Running paper](http://www.sciencemag.org/cgi/content/abstract/329/5994/940) to which I linked. Nevertheless, as [Dave H ](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) indicated, an intelligent lay person should be able to understand the import of the abstract alone.

Speaking of abstracts, here are a few more that indicate what could happen given the best understanding of plant productivity in response to various environmental parameters, an in response to various CO2 emissions scenarios. You will note that growth Nirvana is not heavily featured as a consequence of the several parameter changes contemplated...

Multiple mechanisms of Amazonian forest biomass losses in three dynamic global vegetation models under climate change

David Galbraith1,2, Peter E. Levy1, Stephen Sitch3,4, Chris Huntingford5, Peter Cox6, Mathew Williams1, Patrick Meir1

New Phytologist
Special Issue: This issue contains a Feature on âAmazonian rain forests and droughtâ
Volume 187, Issue 3, pages 647â665, August 2010
DOI: 10.1111/j.1469-8137.2010.03350.x

Summary
The large-scale loss of Amazonian rainforest under some future climate scenarios has generally been considered to be driven by increased drying over Amazonia predicted by some general circulation models (GCMs). However, the importance of rainfall relative to other drivers has never been formally examined.â¢Here, we conducted factorial simulations to ascertain the contributions of four environmental drivers (precipitation, temperature, humidity and CO2) to simulated changes in Amazonian vegetation carbon (Cveg), in three dynamic global vegetation models (DGVMs) forced with climate data based on HadCM3 for four SRES scenarios.â¢Increased temperature was found to be more important than precipitation reduction in causing losses of Amazonian Cveg in two DGVMs (Hyland and TRIFFID), and as important as precipitation reduction in a third DGVM (LPJ). Increases in plant respiration, direct declines in photosynthesis and increases in vapour pressure deficit (VPD) all contributed to reduce Cveg under high temperature, but the contribution of each mechanism varied greatly across models. Rising CO2 mitigated much of the climate-driven biomass losses in the models.â¢Additional work is required to constrain model behaviour with experimental data under conditions of high temperature and drought. Current models may be overly sensitive to long-term elevated temperatures as they do not account for physiological acclimation.

and

Evaluation of the terrestrial carbon cycle, future plant geography and climate-carbon cycle feedbacks using five Dynamic Global Vegetation Models (DGVMs)

S . SITCH*, C. HUNTINGFORDw, N. GEDNEY*, P. E. LEVYz, M. LOMAS§, S. L . PIAO}, R . BETTSk, P. CIAIS}, P. COX**, P. FRIEDLINGSTEIN}, C. D. JONESk, I. C. PRENTICEww
and F. I. WOODWARD§

Global Change Biology (2008) 14, 2015â2039,
doi: 10.1111/j.1365-2486.2008.01626.x

Abstract
This study tests the ability of five Dynamic Global Vegetation Models (DGVMs), forced with observed climatology and atmospheric CO2, to model the contemporary global carbon cycle. The DGVMs are also coupled to a fast âclimate analogue modelâ, based on the Hadley Centre General Circulation Model (GCM), and run into the future for four Special Report Emission Scenarios (SRES): A1FI, A2, B1, B2. Results show that all DGVMs are consistent with the contemporary global land carbon budget. Under the more extreme projections of future environmental change, the responses of the DGVMs diverge markedly. In particular, large uncertainties are associated with the response of tropical vegetation to drought and boreal ecosystems to elevated temperatures and changing soil moisture status. The DGVMs show more divergence in their response to regional changes in climate than to increases in atmospheric CO2 content. All models simulate a release of land carbon in response to climate, when physiological effects of elevated atmospheric CO2 on plant production are not considered, implying a positive terrestrial climate-carbon cycle feedback. All DGVMs simulate a reduction in global net primary production (NPP) and a decrease in soil residence time in the tropics and extratropics in response to future climate. When both counteracting effects of climate and atmospheric CO2 on ecosystem function are considered, all the DGVMs simulate cumulative net land carbon uptake over the 21st century for the four SRES emission scenarios. However, for the most extreme A1FI emissions scenario, three out of five DGVMs simulate an annual net source of CO2 from the land to the atmosphere in the final decades of the 21st century. For this scenario, cumulative land uptake differs by 494 PgC among DGVMs over the 21st century. This uncertainty is equivalent to over 50 years of anthropogenic emissions at current levels.

The previous two look only at temperature, moisture, and CO2 concentrations. Here's one where a simple herbivory factor is included:

Impact of non-outbreak insect damage on vegetation in northern Europe will be greater than expected during a changing climate

Annett Wolf & Mikhail V. Kozlov & Terry V. Callaghan

Climatic Change (2008) 87:91â106
DOI 10.1007/s10584-007-9340-6

Abstract
Background insect herbivory, in addition to insect outbreaks, can have an important long term influence on the performance of tree species. Since a projected warmer climate may favour insect herbivores, we use a dynamic ecosystem model to investigate the impacts of background herbivory on vegetation growth and productivity, as well as distribution and associated changes in terrestrial ecosystems of northern Europe. We used the GUESS ecosystem modelling framework and a simple linear model for including the leaf area loss of Betula pubescens in relation to mean July temperature. We tested the sensitivity of the responses of the simulated ecosystems to different, but realistic, degrees of insect damage. Predicted temperature increases are likely to enhance the potential insect impacts on vegetation. The impacts are strongest in the eastern areas, where potential insect damage to B. pubescens can increase by 4â5%. The increase in insect damage to B. pubescens results in a reduction of total birch leaf area (LAI), total birch biomass and birch productivity (Net Primary Production). This effect is stronger than the insect damage to leaf area alone would suggest, due to its second order effect on the competition between tree species. The model's demonstration that background herbivory may cause changes in vegetation structure suggests that insect damage, generally neglected by vegetation models,
Climatic Change (2008) 87:91â106

And this is before disease dynamics are considered as a response to increasing CO2 concentration and to rising temperature, or before the complex ecological interactions of competing plant species are factored in. Throw all of herbivory, competition, disease, changed bioclimatic envelopes and other unanticipated factors together into the overall mix, and a simple increase in net primary productivity becomes a laughable expectation for anyone but the most naïve and/or uninformed non-scientifically minded ideologue.

If you can't get to any of these because they're paywalled, then you obviously do not work in an institution where scientific communication is a necessary part of business. In this case, I would have to wonder what it is that makes you so convinced that you have the intellectual and the resource capacities to mount a criticism of the scientists who make this their lives' work.

Beranrd and others,

Many thanks for your support. What I have been trying to say in response to Warren's posts is that there are too many unknowns to extrapolate linear, positive outcomes of increasing atmospheric concentrations of C02. The FACE experiments have barely scratched the surface. Rick Lindroth's research has gone a little farther, but I am sure that Rick would be the first to say that fully understanding the ecological effects of altering the chemical composition of the atmosphere is almost impossible. This is because of the enormous number of trait- and context-dependent parameters that chracterize processes and interactions occurring in nature at small scales. The scientific community has spent the better part of 30 years trying to understand the rules that govern the assembly and functioning of ecosystems and yet we've barely scratched the surface. Against this background are a suite of human-induced changes that devalue the importance of short-term experiments to some extent. Yet this is all we have to go on.

To reiterate, there is no way IMHO that we can reliably model the effects of increasing atmospheric concentrations of C02 on the structure, function, resilience and stability of ecosystems. If the effects are plant species-specific, as many of the small scale experiments have tended to show, then the only thing we can reliably predict is that there will be consequences for food webs and ecological interactions that are unpredictable but will be manifested down the road. How long in the future I cannot say, but there is little doubt that it constitutes a blind experiment with potentially serious consequences.

In his outstanding book, Fragile Dominion, which I reviewed for Nature ten years ago, ecologist Simon Levin formulated a list of 'commandments' for managing and protecting the global commons in order to ensure that it continues to function effectively and deliver vital services that sustain humanity. These commandments include the following: (1) reduce uncertainty, (2) expect surprise, (3) maintain heterogeneity, (4) sustain modularity, (5) preserve redundancy, and (6) tighten feedback loops. Tampering with the atmosphere as humanity is doing threatens to increase uncertainty, increase the number of unpredictable 'surprises', decrease heterogeneity, reduce functional redundancy, and weaken feedback loops. This is because the ecophysiological responses of plants will differ within and between communities, leading to asymmetrical responses amongst consumers up the food chain. This much is inevitable. What is impossible to know is how this will manifest itself at larger spatiao-temporal scales. The prognosis is not good. This is why I strongly criticize those who clearly do not appear to understand ecological complexity but nevertheless argue that increasing concentrations of C02 in the atmosphere will be, on the whole, positive.

In summary, there are far too many unknowns to draw such a simple conslusion. And since we are only barely making inroads into the unraveling of ecological complexity, we may not know much until it is far too late to change course.

Bernard J,you may have to forgive me but I find it difficult to take modelling studies seriously.They may be of value,but lets face it,in a stituation as complex as the biosphere,I cant see how they can accurately predict anything.I have a preference for real data from real experiments.Models dont cut it for me.The data from trials still strongly suggests that all things being equal[including temperature],elevated CO2 will give a net benefit to plant growth,generally speaking.If pests and disease incidence increases,then either resistant species will be selected,or humans will find a way to control the pest.This is the whole history of agriculture.By the way,I dont criticize scientists who make this their lifes work.I critique their arguments.

"but I find it difficult to take modelling studies seriously."

This is not our problem.

I take it you don't fly aircraft then, nor drive modern cars.

Computer models.

"in a stituation as complex as the biosphere,I cant see how they can accurately predict anything"

Ah, the excluded middle. funny how planes stay up, computers (also designed by model) work, modern drugs (computer models again) fix ailments and buildings (computer models) still stand up.

"The data from trials still strongly suggests that all things being equal[including temperature],"

1) The data from SOME trials. Most say the opposite.
2) All things are not equal. This is why you're wrong in your conclusion.

"I critique their arguments."

No you don't. You REFUSE to listen to their arguments. And then complain that they keep saying how this is their JOB to understand these things where YOU clearly DO NOT.

Bernard J,I have read the Zhao/Running paper.It was about the effect of drought on regional plant growth.They identified water as the critical factor.

"They identified water as the critical factor."

Now go see what's happening to the Russian plains, the Australian farmlands and the US Southern Midwest.

Oh, looky. Droughts.

But are you saying that droughts are the ONLY factor? Because saying "water is the critical factor" is IN NO WAY proof that more CO2 is better for plants. No matter HOW hard you wish.

Jeff Harvey:This a list of scientists who signed The Manhattan Declaration-They are all Biologists.
1]Ernst Geog Beck2]Rob Seagal3]Mitchell Taylor4]Bruce Borders5]Ian Bock6]Dan Carruthers7]SusanCrockford8]David Bellamy9]Per Engene10]Albrecht Glatzle11]Terrel Johnson12]HaraldKehl13]Jennifer Marohasy14]Les Macdonald
You look google got their various qualifications,but many are PHD's.

TP Hamilton,that 97% to 3%study that you mentioned was the Naomi Oreskes one right?I wont even bother with such thorough debunked trash.

wow, it's been wet in oz,

http://www.tinyurl.com.au/k43

http://www.tinyurl.com.au/k44

Warren,

Are you uniquely qualified to critique any scientist's arguments? Next thing I know you'll claim to have found flaws in someone's work studying microfiliarial tissue in Passerina ciris...

Basically, what comes out of your comments is not anything concrete, but wishful thinking. You HOPE that nature, on the whole, will benefit from increased C02 because it fits in with whatever personal/political agenda that you support. So you ignore the masses of critically important uncertainties that I have pointed out and have highlighted a few studies with very small scale results that fit in with your world view. It is as simple as that.

You cannot win this debate because you are not armed with the knowledge on which to wage it. Certainly, you have read some studies, and that is to your credit, but your inability to grasp the importance of ecological complexity and non-linear processes fatally undermines your thesis, as it does anyone who draws such directed conclusions.

As I have said, very few if anyone who works in the field of systems or population ecology would say that more C02 in the atmopshere will generally benefit nature, on the basis of all of the UNKNOWNS. This view is restricted, for the most part, to those aligned with right wing think tanks or astroturf groups such as C02 Science and the Greening Earth Society. But these groups are just taking the research findings of others and are twisting and distorting it to push their own political agendas. Most statured scientists, and most importantly those doing the actual research, are exceedingly cautious in the conclusions they draw. This is correct - they should be. It is too bad that those pushing political agendas do not possess such restraint. They want black and white answers where they do not exist, and downplay those - like me - who highlight the uncertainties and potentially negative consequences.

I do not mind debating with someone who is willing to acknowlwdge these uncertainties, and who would appreciate how little we know about ecosystems and communities in the broader sense. But most of the time I do not debate actual sceptics in the correct definition of the term, but contrarians on the political right who downplay any number of human threats on the environment: habitat destruction, loss of biodiversity, other forms of pollution, overharvesting etc. Sadly, Warren, you fit the bill. You need to try and learn a bit about complex adaptive systems and then come back at me with your C02-related arguments. Until then I might as well be discussing this with a brick wall.

Jakerman,re your post at 215.
CO2 forces higher temperatures... This is the crux of the debate.We sceptics do not believe that CO2 forces temperature to a great degree.

Wow, it rains, huh?

Just as well I'm sitting down.

And what proofs has the Manhattan Declaration got within it?

"Resolving that scientific questions should be evaluated solely by the scientific method;"

This is done in the research papers and the IPCC synthesis reports.

"Affirming that global climate has always changed and always will, independent of the actions of humans, and that carbon dioxide (CO2) is not a pollutant but rather a necessity for all life;"

Global climate has always changed and always will. The IPCC says this too. But it is NOT independent of the actions of humans.

Animals and plants have always gone extinct and always will. But we still caused the Dodo to go extinct. This wasn't an "irrespective".

And Cyanide is a necessity for complex life. Without it you cannot fight infection. Google apoptosis.

"Recognising that the causes and extent of recently-observed climatic change are the subject of intense debates in the climate science community and that oft-repeated assertions of a supposed âconsensusâ among climate experts are false;"

Yes, they are the subject of intense debates. But this doesn't mean there's no consensus.

The age of the universe is still under intense debate in astrophysics. Yet there is a consensus of "Big Bang" creation.

What arrogant nonsense that declaration is.

And such nonsense that even a layman in biology and chemistry knows how and where they have it COMPLETELY wrong.

This is merely, just as Roy Spencer and that dude from the Creationist Museum have done, the wishful thinking of a few people overriding their sense.

"We sceptics do not believe that CO2 forces temperature to a great degree.

Posted by: warren"

And YOU and your like accuse US of "faith" and "belief".

If it's not 3:1 increase then the effect of CO2 must be higher than 1C per doubling else the current temperature of the earth is inexplicable.

So, warren, explain how the earth is at the temperature it is and has been in the past if you don't get ~3C of warming after feedbacks on 1C of CO2 forcing.

Jeff Harvey:No I am not uniquely qualified to critique any scientists arguments.But I am qualified to post on this blog.If I make errors of fact then please point them out.
The evidence we have to date strongly suugests that there will be a net benefit to the biosphere through aerial fertilization by CO2.Does that mean I am ignoring the uncetainties?Ofcourse not.Because,"the evidence SO FAR suggests" You suggest that it could all go pear shaped.I agree.It could all go pear shaped because of the 'unknown unknowns'.But the evidence so far does not suggest that.You have mentioned that there are many uncertainties and unknowns and that our knowledge is very limited.If that is so then how can you be so certain that elevated CO2 WONT be good for the Biosphere?

> The evidence we have to date strongly suugests that there will be a net benefit to the biosphere through aerial fertilization by CO2.

Sigh. This is your oft-repeated fallacy.

**Some** evidence suggests that this may be the case for a limited subset of scenarios and subjects, but there is plenty of other evidence *that you have been pointed to several times now* that strongly suggests claims of a "net benefit" is drawing a very long bow.

> It could all go pear shaped because of the 'unknown unknowns'.

Not only that, but because of some known known negatives - as you have been pointed to a number of times now, and basically pretend do not exist.

Covering your eyes doesn't make it go away.

> ...there will be a net benefit to the biosphere...

It's also interesting to note that Jeff Harvey, Bernard J and others have pointed out any number of ways in which the biosphere will almost certainly be harmed - but you (seem to) continue to argue a "net benefit".

If you want to make a serious case here, I suggest you start out by defining the full set of metrics that **you** use to quantify "benefit to the biosphere". That should prove illuminating.

>*We sceptics do not believe that CO2 forces temperature to a great degree.*

Your beliefs are simply unsupported pap.

Without CO2 forcing we cannot account for the scale of the [interglacial- glacial cycles](http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch6s6-4.html).

Similarly without CO2 and/or Methane forcing we can't explain the scale of warming events such as [the PETM](http://news.mongabay.com/2006/1207-petm.html).

Warren -- "TP Hamilton,that 97% to 3%study that you mentioned was the Naomi Oreskes one right?I wont even bother with such thorough debunked trash"

Doran et al, published in AGU EOS.

'Examining the Scientific Consensus on Climate Change', Doran (2009)
http://europa.agu.org/?uri=/journals/eo/2009EO030002.xml&view=article

http://www.sciencedaily.com/releases/2009/01/090119210532.htm

In analyzing responses by sub-groups, Doran found that climatologists who are active in research showed the strongest consensus on the causes of global warming, with 97 percent agreeing humans play a role. Petroleum geologists and meteorologists were among the biggest doubters, with only 47 and 64 percent respectively believing in human involvement. Doran compared their responses to a recent poll showing only 58 percent of the public thinks human activity contributes to global warming.

"The petroleum geologist response is not too surprising, but the meteorologists' is very interesting," he said. "Most members of the public think meteorologists know climate, but most of them actually study very short-term phenomenon."

He was not surprised, however, by the near-unanimous agreement by climatologists.

"They're the ones who study and publish on climate science. So I guess the take-home message is, the more you know about the field of climate science, the more you're likely to believe in global warming and humankind's contribution to it."

Jakerman:
1]"..unsupported pap.." No,the null hypothesis puts the burden of proof on those making the claims of CO2 forcing.
2]"Without CO2 forcing we cannot account..." No,CO2 from glacial to interglacial was 200ppm to 280ppm,but the temperature max during interglacials was 6C to 10C higher than today.In order to have diven this kind of temp change CO2 would have to have been 1000ppm.The most likely candidiate for the warming associated with Milankovitch cycles is thought to be changes in surface albedo.Google Marsh/Interglacials
3]The cause of the PETM is unknown,therefore it is not possible to invoke a greenhouse driven mechanism.There is no doubt about the large carbon flux,but what caused it is unknown.

Warren -- "In order to have diven this kind of temp change CO2 would have to have been 1000ppm..."

I beg to differ.

Palaeoclimate: Global warmth with little extra CO2. Birgit Schneider & Ralph Schneider (2010).
(3 - 4C once thought to be associated with CO2 at 500 - 600 ppmv therein put at 385 ppmv)

Coupling of CO2 and Ice Sheet Stability Over Major Climate Transitions of the Last 20 Million Years. Tripati et al (December 2009)

Earth system sensitivity inferred from Pliocene modelling and data. Lunt et al (December 2009)
Hereâs a chart

High Earth-system climate sensitivity determined from Pliocene carbon dioxide concentrations. Pagani et al (December 2009)

Atmospheric CO2 concentrations during ancient greenhouse climates were similar to those predicted for A.D. 2100. Breecker et al (October 2009)

JBowers:thanks for that information on that survey.I have doubts about its findings though.The survey had 3146 respondents,of whom only 5% were climatologists.That is 157 climatologists.97% is 155 believers with 5 deniers.But the problem is that the Oregon petition had 39 climatologists who signed and therefore would be deemed deniers.So that leads to 2 points.First the survey cannot be truely representative of climatologists views,because there appears to be many more denying climatologists than this survey suggests.Secondly,if the surveys findings ARE correct,and it really is a 97% to 3% ratio out there in the scientific world,then going on the numbers from the oregon petition,we would get 39 climatologist deniers[3%]and a whopping 1261 climatologist believers.I have a very difficult time believing that there are 1261 climatologists on planet earth.

"No I am not uniquely qualified to critique any scientists arguments."

We can tell.

"then going on the numbers from the oregon petition,we would get 39 climatologist deniers[3%]and a whopping 1261 climatologist believers"

And this is impossible HOW exactly?

And it's only "belief" in the same sense as people "believe" tables will hold dinner plates.

You seem to have a lot of difficulty thinking. And then you project your PERSONAL INCREDULITY into reality.

'fraid it doesn't work that way, kid.

"No,the null hypothesis puts the burden of proof on those making the claims of CO2 forcing."

I'm afraid not. The proof of CO2's effect is demonstrated by the historical record.

It is YOU who has to show that the historical record doesn't display this.

The problem is you can't prove jack shit, so keep bouncing it off.

YOU say that it's much less than 3:1 feedback forcing.

Prove it.

Prove that the feedback would be less and STILL explain the historical temperatures.

Prove that the feedback would be less and STILL explain the current temperatures.

Prove the feedback would be less and STILL explain the recent rises in temperatures.

YOU have to prove YOUR point. Your point being "the feedback is much less".

Prove it.

First of all, the fact that CO2 is used in photosynthesis has nothing to do with its ability to absorb IR. Increased atmospheric CO2 still means greater absorption. Now maybe you could make the argument that increased CO2 means more plant growth, followed by more uptake in CO2 and then a decrease in atmospheric CO2. there are no credible published studies showing that this happening.

Secondly, as many have pointed out repeatedly, carbon dioxide is only one component of photosynthesis. It will kill plants in a high enough concentration:
http://volcanoes.usgs.gov/lvo/activity/monitoring/co2.php

In the end, this argument is no different than saying that because you need sunlight to make Vitamin A in your body, sunlight cannot cause melanoma.

"maybe you could make the argument that increased CO2 means more plant growth, followed by more uptake in CO2 and then a decrease in atmospheric CO2. there are no credible published studies showing that this happening."

More so, if that were true, why is the CO2 level still going up and the ocean acidity still rising from carbon absorption in the ocean?

If it's "plant food" then obviously, the plants can't eat another bite.

Not even a wafer-thin mint.

Warren writes, "The evidence we have to date strongly suggests that there will be a net benefit to the biosphere through aerial fertilization by CO2".

No, the evidence does not say this in any way, shape or form. What you are doing is saying that we have some basic information on step one of a process [involving very small scale effects of C02 fertilization on plant growth], and that this is enough to explain steps 2 through 100, which increase on an exponential scale in terms of complexity covering trophic interactions through communties and ecosystems to the biosphere. This argument of yours would be shot down in seconds at any conference. It explains why virtually nobody working on complex systems would draw such an outrageous conclusion as you do.

But that was not my point. My point is that the evidence is exceedingly thin because virtually nothing is understood about the effects of C02 fertilization in food webs that involve pathogens, herbivores, predators, as well as processes in the soil. What evidence is in suggests that responses of plants are association-specific (non-linear, in other words). This means that there will be asymmetric effects in small scale natural systems, as some species benefit more than others whilst other species do worse. Changes in primary and secondary chemistry will also occur, amplifying these differences up the food chain. This will affect context and trait dependent responses amongst plants and their consumers. Rapid increase in atmospheric C02 levels will certainly alter the structure of food webs in ways that are impossible to predict. Many of these changes will reduce redundancy, heterogeneity and resilience. But the bottom line is that anyone who claims that the evidence shows that the biosphere will enjoy a net benefit from increased C02, especially at the rates at which it is increasing, are speaking complete gibberish. Perhaps an utter layman like Arthur Robinson thinks he ubnderstands it, but he does not, any more than you do, Warren.

As I said before, Warren, if you want to maintain any credibility in an intellectual debate on this subject may I suggest that you swot up on some simple ecology. As it is, it is clear to me that you do not understand even the basics in this field and are relying on your own limited understanding of small scale ecophysiological processes to get you by. It isn't working.

EdK,yes CO2 can kill at high enough concentrations.And what were those concentrations quoted in the article?20 to 90 TIMES the ambient concentrations.If CO2 is 385ppm now,then 20 times that is 7700pmm.There is not enough fossil fuels existing in the whole world to produce that concentration.

WOW,in regards to the question of feedback from a CO2 doubling,the only 2 measured results that I know of are 1]Lindzen/Choi 2009,and 2]Spencer 2010.Lindzen used the Erbe satellite data and Spencer used the Ceres satellite data.Both were results from observations and both showed negative feedback with a climate sensitivity of 0.5C.This is well below the IPPC estimate based on models of 1.5C to 4.5C.

"And what were those concentrations quoted in the article?20 to 90 TIMES the ambient concentrations"

Workplace concentrations over 1000ppm are forbidden for work shifts of 8 hours. Indoor concentrations are usually quite a bit higher than outdoor concentrations and also note that when the entire earth is at 700ppm, there's not going to be any place to go when your 8 hour shift of living on earth is up.

"in regards to the question of feedback from a CO2 doubling,the only 2 measured results that I know of are 1]Lindzen/Choi 2009,and 2]Spencer 2010."

There's also this:

[The temperature of the earth](http://wiki.answers.com/Q/What_is_the_temperature_on_Earth)

Go ahead and explain it without having a feedback of about 3:1.

"Both were results from observations and both showed negative feedback with a climate sensitivity of 0.5C."

Then they were completely wrong. And I don't mean "a bit wrong" or "misled", but completely and utterly and eternally wrong.

[Read this](http://www.skepticalscience.com/On-temperature-and-CO2-in-the-past.html)

[and this](http://www.realclimate.org/index.php/archives/2006/03/climate-sensitivi…)

[and this](www.clim-past-discuss.net/5/2053/2009/cpd-5-2053-2009.pdf)

among many, MANY others.

Now, on that Roy Spencer comic, the problem here is that Roy removes the temperature trend then uses this to show that temperature change per CO2 change is low.

Well of course it is if you negate the temperature change...

And on Choi et al: [a professional's opinion](http://www.realclimate.org/index.php/archives/2010/01/first-published-r…)

Another problem you've got, warren, is that the satellites don't measure temperature, they only measure radiative intensity, which you need a COMPUTER MODEL

****ALERT!!! ALERT!!! ALERT!!!***

YES, a COMPUTER MODEL.

But, according to you:

["but I find it difficult to take modelling studies seriously."](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…)

So I'm afraid you're going to have to ignore those papers.

How about some other sources?

[Wigley gets ~3C/doubling](http://www.agu.org/pubs/crossref/2005/2004JD005557.shtml) from the cooling from recent eruptions.

[Yokahato gets ~3C too](http://www.agu.org/pubs/crossref/2005/2005GL023542.shtml) using volcanoes again.

From [here](http://julesandjames.blogspot.com/2006/03/climate-sensitivity-is-3c.html) where it also has several other methods that all give their least forced (as in they do not have to assume a propitious confluence of forces in the "right" direction) values for sensitivity of 3C per doubling.

Warren writes:

>*Jakerman: 1]"..unsupported pap.." No,the null hypothesis puts the burden of proof on those making the claims of CO2 forcing.*

The null hypothesis is overturned by the scale of warming necessary for the interglacial and PETM. Hence your claim is pap, that requires blindness and denial of the preponderance of the the evidence.

>*2]"Without CO2 forcing we cannot account..." No,CO2 from glacial to interglacial was 200ppm to 280ppm,but the temperature max during interglacials was 6C to 10C higher than today. In order to have diven this kind of temp change CO2 would have to have been 1000ppm*

Completely unsupported claim, and utterly wrong.
The difference between the top of an interglacial and the bottom (iceage) is 6 degrees C.

Secondly the range is of CO2 in the cycles is 190ppm to 290ppm (a 100ppm range), and the log (ln) forcing nature of CO2 means that differences at lower concentrations have relatively higher forcing.

>*The most likely candidiate for the warming associated with Milankovitch cycles is thought to be changes in surface albedo.Google Marsh/Interglacials*

Again you talk beyond your competence level. Milankovitch cycles were the trigger of the warming, without positive feedback from CO2 we cannot account for the scale of the warming range.

>*3]The cause of the PETM is unknown,therefore it is not possible to invoke a greenhouse driven mechanism.There is no doubt about the large carbon flux,but what caused it is unknown.*

More blindness and denial. The PETM is known to be a sharp spike in both temperature and GHG (CO2 and methane). Without GHG forcing the scale of the warming is unaccountable. Thus your null hypothesis is overturned.

WOW I wonder if Warren enjoyed Spencer's [smackdown of Lindzen & Choi]([http://www.drroyspencer.com/2009/11/some-comments-on-the-lindzen-and-ch…) ?

WOW, Mapleleaf as also linked to [this very useful comparison/evolution](http://bartonpaullevenson.com/ClimateSensitivity.html) of climate sensitivity findings.

Warren says at [#229](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…):

Bernard J,I have read the Zhao/Running paper.It was about the effect of drought on regional plant growth.They identified water as the critical factor.

Right.

So the changes in precipitation and temperature that will accompany further warming will impact on productivity, even with the extra CO2 - just as increased CO2 concentration to date has not compensated for patterns of global precipitation over the last decade when compared with earlier decades.

Oh, and are you sure that you didn't just re-read the abstract? The paper is most definitely about global productivity. If you believe that it's not, perhaps you can explain why every figure - [figure 1](http://i33.tinypic.com/154yr8h.jpg), [figure 2](http://i34.tinypic.com/adn6kx.jpg), [figure 3](http://i37.tinypic.com/11ghpw5.jpg), [figure 4](http://i33.tinypic.com/64ml5d.jpg) - seems to refer to a global context... Interestingly, I am not sure that the methodology of Zhao and Running accounts for regrowth in areas of previous land-clearing, so I'm wondering if the portions of northern hemisphere increase might not be somewhat exaggerated in places, as there is known significant regrowth over recent years in some areas.

Then [at #227](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…):

Bernard J,you may have to forgive me but I find it difficult to take modelling studies seriously.

OK, then explain to us upon what data-versus-model you base your own belief about climate sensitivity. What data do you rely upon in order to discount the many references, linked above, that indicate a sensitivity of around 3 C per doubling of pre-Industrial atmospheric CO2 concentration?

And have you read the Curtin threads yet? They list links that lead to empirical data that show that elevated atmospheric CO2 can increase herbivory, incidence of disease, and competitive disadvantage in plants. Other references show that nutritional content can be reduced. There are also references that show that the resulting temperature increase alone can negatively impact on crop growth - look for the link to the effect that higher night temperatures have on rice production. Or you could learn to do some literature trawling yourself - you might be able to find studies that show that increased CO2 can lead to a greater sequestration of carbohydrate in the roots, negating any productivity benefit to humans.

These are empirical studies. You know, with data. And further, the models that you so disparage use known biological and physical phenomena for their inferences. If you are going to dismiss these models you need to indicate how the known biological and physical effects of altered growth parameters suddenly no longer apply once they are incorporated into a model. Further, you will simultaneously need to explain how your claims that elevated CO2 increase net primary productivity, which are primitives models themselves, do not break this same fact of model unreliability.

> First the survey cannot be truely representative of climatologists views,because there appears to be many more denying climatologists than this survey suggests.

So you don't know anything about sampling theory, I take it, and you're entirely prepared to make unsupported inferences on that basis?

> I have a very difficult time believing that there are 1261 climatologists on planet earth.

Argument from personal incredulity. Convincing? Not.

> ...the only 2 measured results that I know of...

Argument from personal lack of knowledge?

Perhaps you should do some more reading, like the references for climate sensitivity determinations in the IPCC?

> Lindzen/Choi 2009...

...which a little research would show had significant problems.

> Spencer 2010

Spencer tends to pull a little trick - he tries to find a way to calculate (some) short-term (i.e. fast) feedbacks, and then claims *that's all the feedback there is*, which is rubbish. Climate sensitivity is defined at equilibrium, which includes all the slower feedbacks. Ignoring them and claiming you've calculated the climate sensitivity or the total feedback is flat out wrong - and given Spencer's level of education and expertise and *persistence* with this distortion, it's hard to see it as an innocent mistake.

Maybe this paper is different, but I would be quite surprised.

Following [my comment](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…):

>* the range is of CO2 in the cycles is 190ppm to 290ppm (a 100ppm range), and the log (ln) forcing nature of CO2 means that differences at lower concentrations have relatively higher forcing.*

I add the need to also recognise the greater relative abedo feedback when ice is trasitioning to/from mid latidues compared to high latitudes. The solar insoation is higher with lower latitude, so the forcing resulting from changing ice cover is greater at lower latitudes when compared to change in equivalent ice area at higher latitudes.

This higher sensitivity at lower ppm CO2 atmospheric concentrations is consistent with the PETM rise of 5+ degC with addition of [2000 Gt Carbon](http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch6s6-3-3.html) rising from a base of approx [1000 ppm](http://www.realclimate.org/index.php/archives/2009/08/petm-weirdness/) where close to no ice sheet existed.

"WOW I wonder if Warren enjoyed Spencer's smackdown of Lindzen & Choi ?

Posted by: jakerman"

I was going to wait until warren came back with some lame excuse about how the criticisms were invalid because they were done by scare-mongering warmists eating up the gravy train.

There's also Motl's debunking of the paper too.

I don't fancy giving that little streak any links, same as I wouldn't with North or Monckton. Those three are really beyond the pale.

Spencer is merely too willing to give up science in favour of his beliefs and therefore, rather than being a corrosive hate-spewing monster is merely misled by his desires rather than deliberately chundering over humanity like the other three.

WOW,you're kidding!Workplaces dont allow 1000ppm?It takes 10,000 ppm before people even start to become drowsy.And 50,000ppm before it is considered toxic.An over-reaction one might think.
In my view the Lindzen and spencer papers are still compelling results.There have been some valid criticisms of both of them regarding methodology,however that would only affect the scale of the result,and not the finding of a negative feedback.As for the model links that you have given,I would still prefer results from observational data.Lets face it,the models are only as good as the assumptions that are fed into them.If observations are accurately collected,they must be more realistic science than mathematic codes.

Jakerman,two questions.
1]What was the initiator of the PETM?
2]How much energy did this initiator deliver into the system?

"WOW,you're kidding!Workplaces dont allow 1000ppm?"

No, I'm not kidding.

"It takes 10,000 ppm before people even start to become drowsy."

Well, since you're no biologist, I wouldn't expect you to know when that level comes, but funny how you know the figure yet don't know the effects.

[Read up, grasshopper](http://en.wikipedia.org/wiki/Indoor_air_quality#Carbon_dioxide)

"In my view ..."

Ah, we already have eloquent evidence of the accuracy of "your view" (see above CO2)

"Lindzen and spencer papers are still compelling results."

Funny. Spencer doesn't think so of Lindzen's paper.

And funny how you don't have a problem with computer models here that are REQUIRED to turn radiative intensity into a temperature profile.

Then again, a common denier tactic is to change what you'll accept based on the convenience of the moment than any actual rigour.

"As for the model links that you have given,I would still prefer results from observational data."

As for the satellite temperature, please show me where the 50km long thermometer is held in the satellite that it drops down to measure the temperature from actual observations rather than computer models.

Of course this means until you find such a dangling thermometer, your acceptance of the satellite model data is no longer compelling to you IF YOU ARE BEING HONEST.

Of course, you're dishonest and a denier.

> There have been some valid criticisms of both of them regarding methodology,however that would only affect the scale of the result,and not the finding of a negative feedback.

You would be in a significant minority with that opinion - most of whom, perhaps all of whom, don't seem to be able to back up their opinion with robust evidence and logic. Perhaps you might be the one? Please explain how Spencer (or Lindzen and Choi) have captured equilibrium sensitivity (the slow feedbacks) in their analysis?

> If observations are accurately collected,they must be more realistic science than mathematic codes.

Observations are not science in and of themselves, so no - they are NOT more realistic science.

And you seem blissfully unaware that what you dub "mathematic codes" are used in many different places in science (and as others have pointed out in applying science to ... say ... engineering problems where public safety is a major concern).

>*Jakerman,two questions. 1]What was the initiator of the PETM? 2]How much energy did this initiator deliver into the system?*

Several causes are hypothesized. All of them require GHG forcing as the major driver.

One of [Katz hypothesis](http://geology.rutgers.edu/pdf/Katz.etal.2001.pdf) is:

>*erosion along the oversteepened U.S. continental margin
may have allowed methane to escape from gas reservoirs trapped between the frozen hydrate-bearing sediments and the underlying buried Mesozoic reef front.

[Tripati and Elderfield](http://www.sciencemag.org/cgi/content/abstract/308/5730/1894) calculate a change in ocean circulation is consistent with the release of methane.

Further more the The entire event lasted more than 100,000 years. This is also consistent with the [slow rate of carbon removal](http://es.ucsc.edu/~jzachos/pubs/Zachos_Dickens_Zeebe_08.pdf) from the atmosphere.

BernardJ:We need to remeber that the Zhao/Running result was for an ESTIMATED 1% drop in NPP.How you can get a 1% result from satellite data with any degree of confidence is beyond credibility.What were the margins of error?And their main finding was that it was drought that caused the loss of NPP.As for CO2 playing a part in NPP over a 9 year period,surely you are not serious.Over those 9 years CO2 may have increased by maybe 15ppm.And you're saying that 15ppm should have had a detectable effect on NPP?
I have read some of the curtain threads.There are many studies showing the negative effects you mention.However,many other studies show net gains,gains which are larger than any off-setting loses due pests, disease etc.Lower nutritional value has already been covered.Gains due to Higher CO2 are generally lower in FACE trials for crops,but are greater for trees.The Ainsworth/Long 2004 study has a large amount of data on face trials.

"And you're saying that 15ppm should have had a detectable effect on NPP?"

No, but YOU seem to be saying so (when it seems like it could lead to "AGW will be fine!".

Oh, looky. Two faces again. I'm expecting "The Riddler" any moment to come bursting through the door...

"Lower nutritional value has already been covered."

Aye, it has, but you refuse any study that says "there will be lower nutritional value" which is most crops.

"Gains due to Higher CO2 are generally lower in FACE trials for crops,but are greater for trees."

Yah, how many people eat trees? Heck, deer only eat tree when there's naff all else to eat and they're desperate. Because trees aren't very nutritious.

Somehow, though, through the alchemy of your optic centres, this all becomes proof that plants will do better...

Jakerman:So we dont know the cause of the PETM.If we dont know the trigger of the event,then it is only an assumption that CO2 played a role.Your assumption is that CO2 was responsible for the 6C temperature rise.That is debatable.If the 3000Gt carbon flux was in the form of methane,that may be a more likely explanation.In any case the mechanics of the event are unknown,and there is no proof that CO2 was respnsible for the temperature rise.Therefore the PETM cannot be used as evidence that CO2 drives climate

"If we dont know the trigger of the event,then it is only an assumption that CO2 played a role."

No, wrong.

Whatever caused the PETM, there was release of CO2 and that increased warming.

"Your assumption is that CO2 was responsible for the 6C temperature rise.That is debatable"

Only by someone who doesn't care about having another explanation, just refusing (denial of) carbon's role.

"If the 3000Gt carbon flux was in the form of methane"

Which oxidises in about 8 years to CO2.

Over 1000 years, how much do you think will be left..?

Your skepticism only rises to denial of others ideas, never one you like.

"Therefore the PETM cannot be used as evidence that CO2 drives climate"

It isn't being used as evidence that CO2 drives climate. It's used to show that CO2's effect are nowhere near saturated at thousands of ppm and that the feedback response to increased CO2 HAS to be greater than 1 or the PETM becomes inexplicable.

Being inexplicable is fine if you are looking for excuses, but not so good if you're looking for answers.

Everyone reading Deltoid:

Note how Warren has not attempted to address a single point I have made with respect to disentangling the effects of C02 concentrations on processes linking mechanisms at small scales to productivity, reslience, and other ecosystem properties emerging at larger scales. In other words, complexity. He's back to writing this kind of rubbish:

*Over those 9 years CO2 may have increased by maybe 15ppm.And you're saying that 15ppm should have had a detectable effect on NPP? I have read some of the curtain threads.There are many studies showing the negative effects you mention.However,many other studies show net gains,gains which are larger than any off-setting loses due pests, disease etc*

Grade school-level understanding. All of it. The time scales involved are much too short to elucidate the potentially serious consequences of C02 increases. There will almost certainly be threshold-level effects, whereby beyond a certain point systems will shift in their functioning to alternate (and not necessarily stable) states (see work by Martin Scheffer and colleagues on this important aspect of global change biology). We cannot put gigantic containers over entire ecosystems to study the effects of increases in C02, therefore we are left with studies working at greatly reduced spatial scales; moreover, since the effects occurring at small scales may only be manifested in system-wide properties after decades or even centuries (the well-known 'extinction debt' time lag phenomenon I described a few days ago'[ see discussion by Tilman et al., 1994, Nature], then short-term studies performed over the past 10 years may tell us absolutely nothing about longer term consequences of C02 increases for the properties and functioning of ecosystems. We are then left with a mixed-bag of short-term studies looking at mechanisms which show asymmetric responses as well as association-specific effects on primary and secondary metabolites, and other studies in micro- or mesocosms which, as I said, are not long enough to understand the dynamics of more deteministic processes.

Warren, why do you persist? You are a true contrarian, putting your hands over your eyes and ears when the incoming information shreds your arguments. You waded into the wrong place here, pal. You should have stuck with whatever contrartian sites nourish you, whether that is Junk Science, WUWT, or the Idso site. I repeat: we will only know the real outcome of the current atmospheric experiment when it is too late to do anything about it, no matter how serious the repercussions may be. Current studies can only provide snippets of information on potential effects, and aside from the usual suspects, there are few if any scientists who would be bold enough to claim that they are confident that pumping more and more C02 into the atmopshere is a good thing for the natural world. Most would probably agree with me and say the complete opposite.

The planet evolved higher biological diversity - species and genetically distinct populations - in the recent past when C02 levels were comparatively low, at least compared with other times in the planet's evolutionary history and where we are now headed, thanks to the human-induced carbonization of the atmosphere. This means that high ambient C02 regimes are not a pre-requisite for the maintenance of high biodiversity and productivity. Get that through your head. Lastly, given an array of other contemporary anthropogenic assaults across the biosphere, with a concomitant reduction in both species richness and genetic diversity (Hughes et al., 1998, Science), the game of roulette we are playing with the atmosphere may have even more profoundly negative consequences, given that many species may not be able to adapt.

The bottom line is that we do not know enough about the functioning of natural systems to be able to know what the outcome of using the atmopshere as an open sewer will be. But given the consequences could be grave, we should be doing everything in our power to prevent C02 concentrations going beyond 450 ppm, where critical tipping points may be reached. Warren, you are grasping your conclusions out of thin air.

WOW,I am saying that a DOUBLING of CO2 would have an effect on NPP.15ppm would make no detectable difference.
"most crops" No,the studies show that leaf matter loses some Nitrogen-why they are not sure.But generally speaking,the seeds or fruits or roots are not greatly diminished in nutritional value.In cases where their is a decrease nutritional value it is more than made up for by the increase in yield from aerial fertilization.

Warren you are again running away from the preponderance of evidence.

Your appeal to uncertainty is not a get out of jail card for deniers. We still have the preponderance of evidence requiring GHGs to explain the scale of the warming in the PETM, other warming events such as the glacial/inter glacial cycles

>*Your assumption is that CO2 was responsible for the 6C temperature rise.That is debatable. If the 3000Gt carbon flux was in the form of methane,that may be a more likely explanation.*

I refer to CO2 in the broader sense of CO2 equivalent.

BTW "your assumption" that its something else that we can't identify defies scientific logic. CO2e can explain the scale of warming, and the length of warming, and excluding CO2 in favor or 'nothing known' is plain denial.

I should thank you for at least providing a clear (and ongoing) demonstration of AGW denial.

>*In any case the mechanics of the event are unknown*

The mechanics of CO2e fit the PETM and Glacial cycles.

>*and there is no proof that CO2 was respnsible for the temperature rise*

Science doesn't work by proofs, it works on the preponderance of evidence.

>*Therefore the PETM cannot be used as evidence that CO2 drives climate*

Logic fail. Warming events such as the PETM and glacial cycles combined with an array of geological records is evidence of CO2e's integral part in driving climate.

So integral that such events are inexplicable without the role of CO2e. Further more, these geological observations fit reasonably with with current observations, calculated forcing and models.

Jeff Harvey:Your basic argument seems to be that because we dont know what the effects of elevated CO2 will be,we should not mess with the system.Fair enough,but in my view the natural world is a lot more resilient than you suggest.And I strongly doubt that increasing the concentration of a harmless trace gas like Co2 is going to wreak havoc on the natural world.There is no convincing evidence of anything like that happening:infact the evidence points the other way.You seem to suggest that elevated CO2 would throw a spanner in the biospheric works and that would have unpredictable consequences because "the planet evolved when,,,CO2 levels were comparatively low".This is not correct.During the Jurassic period CO2 levels were 2,000ppm.During the Devonian period CO2 levels were 4,000ppm.During the Cambrian period CO2 levels were 7,000ppm.Infact for most of the Earth's history CO 2 levels have been far higher than today.You are completely mistaken in that regard.

Jakerman:
"Science doesn't work by proofs..".Are you kidding?So why did I have to use so much maths in my physics and chemistry classes?
In regards to your belief about CO2,myself and tens of thousands of other sceptics world-wide have looked at the same evidence and concluded that we do not believe that Co2 is a major driver of climate.So we will have to respectfully disagree.Just because we dont know the cause of warming events does not entitle us[scientifically speaking] to name CO2 as the cause by default.

Warren your response to Jeff is just dumb. Re read Jeff post then think about where you went wrong.

Here is a clue, try determining what Jeff was referring to re. "higher biological diversity" and "recent past when C02 levels were comparatively low, at least compared with other times in the planet's evolutionary history".

Warren seem to have let his denial reflex completely bypass his cognition process.

> Your basic argument seems to be that because we dont know what the effects of elevated CO2 will be,we should not mess with the system.

Try reading it again.

The argument is that we don't know what the **full** effects of elevated CO2 will be, but we already have some evidence that indicates that the argument that it must be a net positive is a bogus and inaccurate assessment based on incomplete data, ignoring inconvenient counter-evidence and wild extrapolation.

> And I strongly doubt that increasing the concentration of a harmless trace gas like Co2 is going to wreak havoc on the natural world.

Ah, yes, the "harmless trace gas" mantra of denialists. Funny, it never comes with any evidence that the warming it will cause will be harmless to (say) various important qualities and attributes of the biosphere, never mind individual species.

> You seem to suggest that elevated CO2 would throw a spanner in the biospheric works and that would have unpredictable consequences because "the planet evolved when,,,CO2 levels were comparatively low". ... Infact for most of the Earth's history CO 2 levels have been far higher than today.You are completely mistaken in that regard.

Geez, you must be desperate to put words into Jeff's mouth by egregiously butchering his quote [my emphasis on the bits you left out]:
> The planet evolved **higher biological diversity - species and genetically distinct populations - in the recent past** when C02 levels were comparatively low...

Jeff's sentence talked about the planet *evolving higher biological diversity*; your butchered quote talked about evolution *of the planet*. Major difference.

And thus your argument that Jeff is "completely mistaken in that regard" is itself completely mistaken.

> Jakerman: "Science doesn't work by proofs..".Are you kidding?So why did I have to use so much maths in my physics and chemistry classes?

Because you use the maths to assess the evidence.

> ...myself and tens of thousands of other sceptics world-wide have looked at the same evidence and concluded that we do not believe that Co2 is a major driver of climate.So we will have to respectfully disagree.

And like pretty much all of those skeptics, you will respectfully disagree without being able to publish a single paper that shows a better explanation, or even an explanation that remains plausible and consistent with the evidence after even mild scrutiny from scientists competent in the field.

And yet it warms.

>*Science doesn't work by proofs..".Are you kidding?So why did I have to use so much maths in my physics and chemistry classes?

Because quantifying and analyzing observations and relationships are helpful tools and lead to useful insight.

>*In regards to your belief about CO2,myself and tens of thousands of other sceptics world-wide have looked at the same evidence and concluded that we do not believe that Co2 is a major driver of climate.*

No you haven't, you [demonstrated](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) clearly and [consistantly](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) that you [ignore evidence](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) that conflicts with your beliefs. And you've demonstrated you are certainly no skeptic.

>*Just because we dont know the cause of warming events does not entitle us[scientifically speaking] to name CO2 as the cause by default.*

"By defualt"? You really have raised the white flag and given up on reality.

When the preponderance of evidence points to CO2 and you've got nothing better it is anti-science to reject CO2e as the likely candidate.

Understand that warren? There is a difference between "default" and preponderance of evidence. I understand it might be difficult for someone practicing reflex denial to distinguish the two.

"myself and tens of thousands of other sceptics"... should read,

*myself and tens of thousands of other mostly scientifically illiterate sceptics*...

"in my view the natural world is a lot more resilient than you suggest" should read,

*in my completely simplistic view that lacks any real empirical understanding of how complex adaptive systems function, the natural world is a lot more resilient than you suggest*

As far as your total misinterpretation of my statement re: biological diversity, I was referring to diversity in terms of species richess and genetic variation which we now know was probably higher in the recent past (the Holocene, about 8,000 ybp until recently, when humans triggered the planet's 6th mass extinction event), than at any other time in the planet's history. Trust you to completely hash that up.

Every post you make sinks you deeper into the primordial ooze, Warren...

"WOW,I am saying that a DOUBLING of CO2 would have an effect on NPP."

And you have NOTHING to say that this effect will be net positive.

You just can't stop spewing falsehoods (of certainty when you have none, and uncertainty when there are things to be certain of), can you.

All you have is deny, deny, deny.

warren,

>"WOW,I am saying that a DOUBLING of CO2 would have an effect on NPP."

And I'd qualify your statement to say that a doubling of CO2, in and of itself (alone, and out of context), would in all probability result in a NPP increase. You could even consult the primary literature and arrive at a range of plausible values for this increase.

Now add in all the side effects expected from this doubling of the CO2 (as before, use the range of expected effects published in the literature, both sets of values are equally valid), and try and show that there will STILL be a net increase in NPP, and that this will translate into something of benefit to us.

The many who have done this before you don't seem to agree. [This here](http://www.science.org.au/reports/climatechange2010.pdf) is a good starting point / summary, especially section 6.

The latest nail in the coffin for those arguing for the benefits of increased atmospheric C02:

http://jgs.geoscienceworld.org/cgi/content/abstract/167/5/843

Two weeks ago the Boyce et al. study in Nature showed that chlorophyll levels in the oceans had exhibited precipitous declines over the past century. Now this study comes out, showing that rising C02-mediated acidification of the Mediterranean Sea is having similar dramatically negative biological effects.

Warren and his ilk are being hung out to dry.

An excellent video further demolishing the benefits of increased C02" myth...

http://kgarry.wordpress.com/2009/07/12/co2-as-plant-food-the-latest-glo…

Jeff Harvey:"I was referring to..."No you weren't Jeff,you specifically used the word 'evolved'.Now you're trying to wriggle your way out by suggesting they were existant species.You know that most plant evolution occurred continuously during the devoinan and carboniferous periods to the permiam and triassic/jurassic.For most of those periods the CO2 level was higher.Even in the cretaceous period the level was 2000ppm,and in the teriary 1000ppm.So given all that when was this "recent"evolutionary period that you speak of?

>*Jeff Harvey:"I was referring to..."No you weren't Jeff,you specifically used the word 'evolved*

Warren try doing [as I suggested](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) and you wont look such a complete fool.

[What a sorry train wreck Warren is turn out to be].

Warren,

DO NOT PUT WORDS IN MY MOUTH!!!!!

I was saying that the planet evolved its highest levels of diversity in terms of species richness and genetic diversity in the recent past, under comparatively low C02 levels... JAkerman and Lotharsson understood exactly what I meant! I do not need a scientific neophyte like you to explain to me what I meant in my posting. You have clearly shown yourself to be well out of your intellectual depth in this topic, hence why you constantly 'bait and switch' and have moved onto other threads.

The point is that high C02 levels are not a pre-requisite for the evolution and maintenance of high biodiversity and for systemic stability and resilience. In fact, it may be quiter the opposite, if there are concetrations of C02 beyond which concentrations of other nutrients are compromised, as well as vital plant functions. Furthermore, even if plants could adapt to higher levels of C02, under normal conditions atmospheric changes would not be occurring at the rate that they are now, that is within one of two human generations. Natural selection is directed but the arising of genetic mutations is not; consequently, the current rate of increase will certainly be beyond the ability of many plants and their consumers to respond.

I would relish debating someone like you face to face at a conference, because I would utterly annihalate your arguments. But since 0.00001% of scientists working in relevant fields would come anywhere close to the conclusions you are drawing (that is because as scientists they would be severely criticized for doing so, whereas you only draw the ire of people like me on weblogs) it is virtually impossible that I will ever hear a talk from a qualified biologist who espouses such outrageous views as you at any major workshop or conference.

> Now you're trying to wriggle your way out by suggesting they were existant species.

Epic comprehension fail - yet again.

If you want to debate these points, it is a necessary pre-condition that you understand the distinction between what Jeff wrote and how you re-wrote it. You clearly don't - or won't.

Jeff Harvey:OK Jeff,I apologise for sort of miss quoting you.In your reply you again mentioned "recent past" in regards to species richness and genetic diversity.Just to clarify,exactly when do you mean when you talk about 'recent past'?

Warren if you read Jeff's the next post (after the one I referred to [here](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…)), you would have read the answer to @292.

Jakerman:So do you mean that the 'recent past' that Jeff speaks of is the Holocene-8000 ybp.Is that his answer?If it is,then fine.But it does not change the fact that most plant species evolved during peroids of higher CO2 levels.That strongly suggests that plants could tolerate,and probably thrive with enhanced CO2.

"But it does not change the fact that most plant species evolved during peroids of higher CO2 levels"

How many species of plant were alive at the peak you consider to be in the distant past?

How many species are there alive at this time and how many was the peak number in the past maybe 2 million years?

Since you've stated that it is a fact that most plant species evolved at higher levels, you should have these figures.

WOW,no I dont have those numbers.The fossil record show the development of plant species over the epocs,and we have fairly reliable proxy derived estimate of CO2 levels over the same times.Matching them up shows that most plant life 'evolved'in times of higher CO2 levels.

"WOW,no I dont have those numbers."

Then how do you know this is a fact:

"But it does not change the fact that most plant species evolved during peroids of higher CO2 levels"

?

"Matching them up shows that most plant life 'evolved'in times of higher CO2 levels."

HAHAHAHAHAHAHAHAHAHAAA!

So over a 2 billion year period more plants evolved (and died) than during a 0.000008 billion year period and you think that proves that CO2 is good for plants?!?!?!

Might as well say "More plants have died when CO2 levels were higher therefore CO2 is deadly to plants".

Warren, the greatest biodiversity existed in recent times with recent climate. This is not evidence that the biodiversity that supported us will thrive.

Jeff Harvey:the Boyce et al study was just a backcast and the proxy data they use for plankton does not show any real trend over the period of the observations.Again how you can derive a reliable result of "~1% per year" in such noisy data is beyond me.
The other study is an interesting one.Firstly,the authors seem to ascribe the PH change around the gas vents to CO2.This is impossible.The acidification is more likely due to SO2 as the resultant Sulfuric acid is much stronger than the weak Carbonic acid produced by CO2.Secondly,how can they determine that it was lower PH that killed off the Foraminifera.In order to do that they would have to exclude the other constituents of vent gases like hydrogen flouride,Hydrogen cloride,and Carbon monoxide.I would like to read the full study,but I cannot find it anywhere.

Jakerman:No,you are right it is not evidence.But if plants evolved[generally speaking]in times of higher CO2 levels,and if recent evidence shows that low CO2 is a limiting factor for growth,then it stands to reason that plants could atleast tolerate,if not thrive,under higher CO2 levels.

warren, plants went extinct generally speaking in times of higher CO2.

Therefore by your assertions, CO2 is a plant poison.

WOW,there is no evidence[that I know of] that elevated CO2 was responsible for plant extinctions.However,a study by Shwarz found that there were some signs of toxicity in maize grown in 10,000pmm CO2.

Warren,

Wrong again. For the billionth time, carbon dicoxide is not a limiting factor for the growth of many plants. Do you not read what I write? Have you not watched the last video I sent? As I said, plant species richness, at least until humans began decimating forests in many parts of the world, was higher recently than at any other time in the planet's history. By recently I mean up until several thousand years ago. This is because the biotic and abiotic factors that generate diversity are context- and trait-dependent and do not at all depend on higher C02 levels. As I have said time and time and time and time and time et al. again, nitorgen and phosphorus are also important determinants of plant growth and, more importantly, quality.

And of course I have blown this stupid overly simplisitic C02 is good for nature myth out of the metaphorical water many times before by arguing about the potentially strong asymmetrical effects on the dynamics of non-linear systems. This is because humans are altering the chemical composition of the atmosphere in the blink of an evolutionary eye. We are not talking about thousands of years or even centuries but decades, and many, perhaps most species of plants and their consumers are not adapted to high ambient C02 levels. Certainly if the change were to be gradual, meaning several centuries at the very least, I might believe that the genetic variation (already reduced by other human actions) necessary for rapid adaptation would be present in much of the world's biota. But, as I said, 50-100 years is not long enough. It is just too bad that humans perceive time scales very differently from those experienced as constraints in complex adaptive systems. We think 80 years is a long time, and this is because we are not evolutionarily programmed as a species to respond to what we inherently feel as gradual threats to our survival which, in actual terms, are exceedingly rapid. This is why only nincompoops argue that Polar Bears will 'adapt' to losses of pack ice by adapting behavior similar to their brown bear cousins over the coming century. It also explains why people think that plants will linearly benefit from rapid atmospheric increases in C02, even if most extant plant species evolved under and are thus adapted to low C02 regimes. It is utter nonsense when we take into account ecological complexity.

So my question Warren to you is this: Why do you keep coming back with this crap? Is it because you have a built in mental barrier in your head in which anything logical or complex bounces off? How many times must I demolish them, only for you to say effectively the same things you have been saying since you started writing here? Is it because you believe that you can be an 'armchair expert' and thus dismiss the arguments of those who have spent years in the similar fields of research? Which is it?

I am beginning to think that none of us here (including me) should respond any more to Warren's gibberish. As long as we do, he will repeat *ad nauseum* the same simple arguments that have been repeatedly debunked.

"WOW,there is no evidence[that I know of] that elevated CO2 was responsible for plant extinctions"

They are extinct.

How much more evidence of it do you need?!?!

Odd how all you need to support *your* position is "well, there are more plants in the 2 billion years when CO2 was higher", but when the same argument leads to "CO2 is a plant poison", suddenly this is not enough.

I can see your two faces again...

Warren,

The Boyce study has been widely discussed in scientific circles and in the media. Fore some reason I tend to trust the conclusions of qualified marine biologists over unqualified denialists, even if they think they possess the necessary acumen. Moreover, Warren, have you written to Nature to point out the errors in the Boyce et al. study? If not, why not?

As for thr other study:

*The study identified a tipping point at âmean pH 7.8â³:
The scientists, from the University of Plymouth and the University of Santa Catarina, Brazil, studied a single celled organisms called Foraminifera around volcanic carbon dioxide vents off Naples in Italy. The study, published in the September issue of the Journal of the Geological Society, found that increasing CO2 levels caused foram diversity to fall from 24 species to only 4*.

*Previous studies have shown a reduction in diversity of 30%, but this is even bigger for foramsâ, said Dr Jason Hall-Spencer, one of the studyâs co-authors. âA tipping point occurs at mean pH 7.8. This is the pH level predicted for the end of this centuryâ*.

We know that increasing atmospheric levels of C02 lead to the acidification of water bodies, due to concomitantly lower levels of pH. It should be a no-brainer to realize that lowering levels of pH in seawater will imperil the survival a great deal of marine life from the basal end of the food chain up. The recent studies that I have highlighted should be seen as enough of a warning sign, ignoring the many also occurring in terrestrial ecosystems, that pumping more and more C02 into the atmospher is a recipe for disaster. Humans simply cannot manage complex adaptive systems because we do not yet fully understand how they work. Against this background, we have a small bunch of people, mostly non-academics, arguing that tinkering with the atmosphere on a large scale has minal risks and therefore we should do nothing about it. Many of these people are distorting the findings of empirical and theoretical research to promote a pre-determined world vieww and political agenda. They ar eliterally gambling with the future.

IMHO its crazy. Nuts. Madness. And as a senior scientist, I will continue to voice my profound concerns over the inherent risks in this aspect of global change, as well as in the other number of areas in which humans seem intent on undermining the functioning of our ecological life support systems.

WOW,do you have any evidence that elvated CO2 led to the extinction of plants?

"WOW,do you have any evidence that elvated CO2 led to the extinction of plants?

Posted by: warren"

Yes.

The extinct plants.

Jeff Harvey:CO2 IS a limiting factor on plant growth for many,if not a majority of species.Miglietta[1999]grew potatoes in 600-700pmm CO2 and had an average increase in tuber yield of 44% in one of the trials.Jeff,you have not demonstrated that elevated CO2 will be bad for plant life,while I have provided a number of studies that strongly suggest that it will.You must accept the evidence that extra CO2 has promoted plant growth in the majority of studies.To deny that evidence is delusion.
PS Ocean PH varies from time to time and by large amounts.We have had lower PH's in the past and everything seemed to survive.

"CO2 IS a limiting factor on plant growth for many,if not a majority of species"

No, not a majority of plants as you yourself asserted earlier:

["They identified water as the critical factor"](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

"We have had lower PH's in the past and everything seemed to survive."

Really? Where are the velociraptors then?

WOW,so if CO2 did kill those plants off,then doesn't that mean that the plants that suvived[the ones we have now] would be able to tolerate high CO2?

"doesn't that mean that the plants that suvived[the ones we have now] would be able to tolerate high CO2?"

No, it means that they are alive because CO2 is low.

[Or was](http://en.wikipedia.org/wiki/File:Carbon_Dioxide_400kyr.png)

Your query is rather like saying "since people were eaten by sabre tooth tigers, why are there still humans around?".

WOW,I am not sure I understand what you mean.You say that High CO2 made plants go extinct.Did all the plants go extinct or just some?

"You say that High CO2 made plants go extinct."

I'm saying that your logic would have this true.

Most plants went extinct in the past when we had much higher levels of CO2.

Therefore CO2 kills plants.

That's the exact same reasoning you used and accepted. Why do you refuse that reasoning now?

WOW,I never said that CO2 made plants go extinct,you did.I was addressing Jeff's point about when plants evolved.I pointed out that plant evolution happened mainly during periods of high CO2.And therefore it should stand to reason that plants today could tolerate high CO2.

"WOW,I never said that CO2 made plants go extinct"

Yes you did [here](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…)

1) More species died in the past where we had higher CO2
2) Therefore CO2 must be bad for plants

"I pointed out that plant evolution happened mainly during periods of high CO2."

But additionally at those times of high CO2, higher levels of plant extinction occurred.

Therefore CO2 is a plant poison.

WOW,with all due respect mate,you are out of your freaking mind!

No, warren, you're [projecting](http://en.wikipedia.org/wiki/Psychological_projection) again.

That is YOUR logic used there and following it leads to CO2 is a plant poison.

Either the logic is sound in which case the conclusion is correct.

Or the logic is not sound therefore [this:](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) is not sound.

You're just pissed off that you haven't been able to make the same arguments on different threads without having them being shown up.

Goldfish.

Warren,

Sigh. You are really exasperating. Clearly my discussions of ecological complexity and non-linearity sailed right over your head. Not much I can do about that.

The results that you explained were conducted under controlled greenhouse conditions, excluding just about every biotic and abiotic constraint that occursd under natural conditions. Natural systems are self-organized and exist on a 'critical edge' (see Levin, 1999, for a discussion). And I have cited studies showing thatcarbon is not necessarily a limiting nutrient for plant fitness. Moreover, plants are bad enough food as it is because C:N:P ratios are far too high in favor of the former; increasing the amount of carbon in plant tissues is not a good thing for herbivores which are mostly N limited. Moreover, studies in Australia have shown that increases in atmopsheric carbon alter the investment into toxic alleochemicals meaning those plants with C-based toxins become even more toxic under elevated C02 regimes. I am not saying that C02 is bad for plants, but that we must consider a wealth of ecophysiological parameters if we are to understand what effects the human experiment is having.

But I have said all of this before and not one iota has been registered by you. But I have no need to convince you; the scientific community by and large recognizes the multiple threats to nature, even if people like you do not. Contrarians are all the same: dismiss studies in the most rigid journals if they do not fit in with their pre-determiend worldview.

*Ocean PH varies from time to time and by large amounts.We have had lower PH's in the past and everything seemed to survive*

This statement alone clearly reveals your lack of understanding of basic evolutionary biology. Certainly atmsopheric C02 concentrations were much higher in the past. So were temperatures. So what? The important point is under what C02 and temperature regimes current biota evolved under and to which they are adapted. Species exhibit evolved tolerances to abiotic (and biotic) parameters. Beyond certain abiotic thresholds they must expend more energy in order to survive. Why do most species exhibit well-defined local and global geographic and habitat-related distributions? Because conditions are optimal enough within these abiotic 'envelopes' for them to reproduce and survive.

The planet now is made up of species that evolved under comparatively low C02 regimes and higher marine pH levels, as well as regional climatic regimes. Certainly, as I said yesterday, were changes in abiotic processes mediated by human activities to occur gradually, say over a millenium or longer, I am certain that many, perhaps most, species would survive and adapt. But we are forcing changes in biogeochemical cycles and climate that are occurring faster than at any time in millions of years. Climate control systems are largely determinsitic because they encompass stupendous spatio-temporal scales. The same is true of atmopspheric C02 levels, which are rising at rates probably unsurpassed in tens of millions of years (or longer). Previous extinction episodes were driven by rapid changes in abiotic processes as a result of intense volcanic acitvity, asteroid impacts, etc. In the current scenario, humans are the culprit, and given that we have already simplified nature in a wide number of different ways, we are exacerbating the problem by forcing rapid changes in climate and atmospheric concentrations of C02.

So your point is vacuous and mute. The key is local adaptation amongst contemporary biota, and not what now-extinct organisms were adapted to in the early Cenozoic and before whehn abiotic conditions were different. Of course any biologist knows this. Your inability to grasp it tells me all I need to know about your 'knowledge' (or lack thereof). Whenever I read Warren's posts, I see those Dunning-Kruger alarm bells ringing again...

And in the meantime...

Geological Society: Acidifying Oceans Spell Marine Biological Meltdown 'By End of Century'

http://www.geolsoc.org.uk/gsl/views/page8336.html

"âThese are the first CO2 vents to be used to study ocean acidification. They allow us to observe how ecosystems react to changes in ocean acidity. We can see for our own eyes what increasing CO2 levels do to marine communitiesâ.

âAt a mean pH level of 7.8, calcified organisms begin to disappear, and non calcifying ones take over. We are headed towards that being the case in this century. The big concern for me is that unless we curb carbon emissions we risk mass extinctions, degrading coastal waters and encouraging outbreaks of toxic jellyfish and algae.â"

>*if plants evolved[generally speaking]in times of higher CO2 levels*

Not the plants we've selected via breeding to [co evolve](http://www.kew.org/science/ecbot/papers/nesbitt2001wheat.pdf) with our development and latter civilization.

To put things into perspective we are set to change CO2 and temperature back to levels somewhere between the Oligocene and the Eocene. The transition between those two Epochs is marked by the [Grande Coupure](http://en.wikipedia.org/wiki/Eocene#Grande_Coupure) a time of forced change.

>*and if recent evidence shows that low CO2 is a limiting factor for growth*

You again leave out water, temperature, other nutrients, and the evidence that shows CO2 retarding some growth. You need to consider the net effect, something you seem loathed to do.

" "and if recent evidence shows that low CO2 is a limiting factor for growth"

You again leave out water"

[Only sometimes](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…). He ignores it when it suits him and uses it when he likes.

> Jeff,you have not demonstrated that elevated CO2 will be bad for plant life,while I have provided a number of studies that strongly suggest that it will.You must accept the evidence that extra CO2 has promoted plant growth in the majority of studies.To deny that evidence is delusion.

Warren, I'm not speaking for Jeff but I don't see him denying that evidence. What is see is him (and others, myself included) pointing out that it's not germane to the relevant questions, and you don't seem to understand that you're *asking the wrong question*. Or to put it another way, you're extrapolating way beyond reasonable bounds.

What you're arguing is a bit like stating that consuming lots of anabolic steroids leads to bigger muscles, so anabolic steroids improve human health. Plenty of doctors would point out that those steroids have additional significant and nasty health effects, so it isn't obvious that they improve human health overall, and indeed under most circumstances and ways of measuring health one would expect that health actually decreases - sometimes dramatically, even to the point of death.

It's not particularly important whether more CO2 leads to more biomass - because humans (and the rest of the ecosystem that consumes plants) don't actually care about how much bio**mass** they consume; they care about how much healthy plant-based nutrition they consume weighed against the side effects of their consumption of all the other stuff in those plants. (The latter is why Jeff keeps trying to get you to understand that higher CO2 makes many plants less digestible - and even more *toxic*).

The important question is whether more CO2 - and all of the associated climatic changes - will lead to (a) a healthier (or at least as healthy) ecosystem overall, and (thinking anthropocentricly) (b) improved agricultural output of food that ultimately *humans* can consume without significantly increasing negative side effects of consumption.

This is not a question that can be answered by the types of simple CO2-increase studies you've been citing.

Jeff Harvey: The trials were not all indoors jeff,many were open air.Bernacchi,Kimball[2007]Please get it through your head that the FACE trials show increased NPP.The study you refer to in Australia is not the Gleadow study is it by any chance?That study was funded by a left-wing mog with ties to that Charlatan Tim Flannery.

Jeff Harvey: The trials were not all indoors jeff,many were open air.Bernacchi,Kimball[2007]Please get it through your head that the FACE trials show increased NPP.The study you refer to in Australia is not the Gleadow study is it by any chance?That study was funded by a left-wing mob with ties to Tim Flannery.

>*The trials were not all indoors jeff,many were open air.Bernacchi,Kimball[2007]Please get it through your head that the FACE trials show increased NPP.*

"Get it into your head" warren that we've already pointed out the flaw in your argument of citing trials that do not test the impacts of other factors such as rising temperature. I've shown you studies that show CO2 elevation can retard growth in such conditions.

Jeff says:

I am not saying that C02 is bad for plants, but that we must consider a wealth of ecophysiological parameters if we are to understand what effects the human experiment is having.

To which Warren responds:

Please get it through your head that the FACE trials show increased NPP.

Lothersson:And I have repeatedly pointed out to Jeff that the increase in total biomass makes up for any decrease in protein.In fact it more than makes up for it.The study by Bloom[2010] did in deed show a -11% change in protein concetration in wheat.But Amthor[2001] did a review of 24 outdoor studies that showed that under a doubling of CO2,the yield increase in wheat was 31%.That means that while protein concentration is decreased,the total amount of protein is greatly increased.Here is the working.For every kg of wheat produced under ambient CO2, we get a 31% increase under Elevated[~800ppm]CO2.So that means 1.31kg.But the protein concentration under elevated CO2 is lower by 11%.So mutliplying 1.31 by .89 will give up the new total protein amount which would be 1.166.Therefore a 16.6% increase in total protein.The conclusion,with all other factors being equal,is that our crops will have more total nutrition under higher CO2 levels.

".... with all other factors being equal ...."

Hah. You were in the same lecture theatre as me doing Economics I, weren't you!

Only one problem. It's never been true for real life economics and it's not true in real life agriculture or ecology or climate.

One of the most fascinating things about the denial blog phenomenon is the way they ... ah... empower rank amateurs who've read a couple of papers to be able to 'correct' professional scientists.

And why stop there?

Bone up on a couple of nuerology papers over the weekend and come Monday you too could be advising brain surgeons, or berating them for not getting your speed-read, practice-free version of somebody else's work into their thick heads.

Warren writes:

>*And I have repeatedly pointed out to Jeff that the increase in total biomass makes up for any decrease in protein.In fact it more than makes up for it[...] Amthor[2001] did a review of 24 outdoor studies that showed that under a doubling of CO2,the yield increase in wheat was 31%. That means that while protein concentration is decreased,the total amount of protein is greatly increased.*

What [Amthor found](http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T6M-4471GDJ-…):
>*Usually, modest warming (1â4°C) counteracted positive effects of doubled [CO2] on yield. Combinations of rising temperature, [CO2], and [O3] may result in positive or negative effects on wheat yield, though the [CO2]-effect per se will normally be positive. Predictions of effects of rising [CO2] on wheat yield carry with them intrinsic uncertainty.*

Warren, your cherry picking and denial is beyond a joke.

> And I have repeatedly pointed out to Jeff that the increase in total biomass makes up for any decrease in protein.

Your assertion is dubious. It's like the steroid-using body builder saying that as far as his health goes, the increased muscle mass makes up for the decrease in sexual function and increase in heart stress. When the doctors point out that his claims are based on false accounting (citing perhaps the increased risk of early death or incapacitation from any number of direct medical and other indirect causes - including poorly timed roid rage incidents), he continues to assert that he is healthier because the extra muscle mass makes up for the sexual function and heart stress.

In other words, you are **still** are incapable or unwilling to comprehend this point:

> The important question is whether more CO2 - **and all of the associated climatic changes** - will lead to (a) a **healthier** (or at least as healthy) **ecosystem overall**, and (thinking anthropocentricly) (b) improved agricultural output of **food that** ultimately **humans can consume** without **significantly increasing negative side effects of consumption**.

Go back and read it again - not just the clauses you robotically repeat your claims in response to, but *all of them* (including the ones I highlighted).

For one thing - and certainly not the only thing - you're stupidly treating this as a linear and deterministic arithmetic problem. If I factor in this "31%" with this "-11%" I come out ahead, right? You've *completely* ignored the **stochastic influences**! Here's just one pointer - go read the papers linked on the Tim Curtin thread on how badly yield can be damaged for some crops by only **a few hours** of higher temperatures at the critical point in the growing cycle. And then show how the trials that you quote model **that** kind of stochastic factor on global agriculture in their "31%" results. And once you've done that, show how they model **all** the other factors beyond CO2 and temperature (some of which - like Tim Curtin - you've been repeatedly pointed to and refuse to acknowledge) - globally. Can you?

And in addition, ask yourself **how many** reasons you can find why even several very limited trials might not extrapolate reliably to a whole globe's worth of agriculture. Feel free to post them here - it might help your credibility a smidgin if you show you **can** think beyond your current egregiously simplistic assumptions.

warren @330:

And I have repeatedly pointed out to Jeff that the increase in total biomass makes up for any decrease in protein

In one trial, on one species. And even then, as jakerman @333 points out, the authors of the paper quite rightly hedge their conclusions with numerous caveats.

The conclusion,with all other factors being equal,is that our crops will have more total nutrition under higher CO2 levels

So you take one study on one crop species, and then extrapolate to say ALL other crop species will follow the same path? Really?? Any evidence? Let's assume (a big assumption) it holds true for all cereal crops - what about root crops (spuds, sweet potato, carrots etc etc.)? And, in case it needs pointing out to you, that little phrase "all other things being equal" covers a whole range of sins you don't seem willing to think about, let alone acknowledge, like water availability (and, critically, soil water availability), increased transpiration rates, and extreme weather events.

But let's assume you're right and that increased biomass cancels out the effects of all other mechanisms (an even bigger assumption, but anyway...) in wheat - what then about the other ~400 000 plant species? How will they cope? Will all of them follow this model? Some? Which ones? What of the multiple layers of interaction between plants, soil, soil fauna, invertebrates, herbivores, secondary and tertiary heterotrophs and so on? How does this alleviate significant concerns about inter alia out-of-phase flowering, reduced or absent fruit set, reduced fruit and seed dispersal due to out-of-phase or poor flowering, reduction in forage for heterotrophs (and knock-on effects such as reduced vigour, increased mortality, reduced breeding), and reduction of or significant changes in soil formation and soil fertility resulting from changes in the amount of leaf litter produced and/ or changes in the chemical composition of that litter?

On FACE experiments, the one I'm vaguely familiar with is the one run by the University of Western Sydney, which has been running a few years. The lead scientist (Prof David Ellsworth) co-authored an interesting paper in 2008 on forest fine-root production and nitrogen use under elevated CO2. The abstract states:

Despite the importance of nitrogen (N) limitation of forest carbon (C) sequestration at rising atmospheric CO2 concentration, the mechanisms responsible are not well understood. To elucidate the interactive effects of elevated CO2 (eCO2) and soil N availability on forest productivity and C allocation, we hypothesized that (1) trees maximize fitness by allocating N and C to maximize their net growth and (2) that N uptake is controlled by soil N availability and root exploration for soil N... The model explains why fine-root production increased, and why N uptake increased despite reduced soil N availability under eCO2 at ORNL and Duke. In agreement with observations at other sites, the model predicts that soil N availability reduced below a critical level diminishes all eCO2 responses. At Duke, a negative feedback between reduced soil N availability and N uptake prevented progressive reduction in soil N availability at eCO2. At ORNL, soil N availability progressively decreased because it did not trigger reductions in N uptake; N uptake was maintained at ORNL through a large increase in the production of fast turnover fine roots. This implies that species with fast root turnover could be more prone to progressive N limitation of carbon sequestration in woody biomass than species with slow root turnover

(my emphases).

The first point (about limitations of available N affecting C uptake) is something you conveniently ignore, even though it's a critical factor. Secondly, one obvious question arising is - which are those species more prone to fast fine root development? Well basic plant biology indicates that it's generally monocotyledons. And what does the group monocotyledons include? Grasses. Cereals, in other words...

Is any of this sinking in? Can you see why your single-track focus on protein levels in wheat (even while you ignore the caveats the authors state) in response to the multi-factor objections raised by others (notably Jeff Harvey, who has one or two clues about this stuff, and Lotharsson and jakerman) doesn't even touch the sides? Am I wasting my time (rhetorical)?

>*So you take one study on one crop species, and then extrapolate to say ALL other crop species will follow the same path?*

Unfortunately warren did worse than this. He took one study and cherry picked the bit he like and ignored the finding that a rise in temperature of 1 to 4 degrees will usually counter act the positive effects of increasing CO2.

Then we have to deal with the more complex ecological consequences, and other problems such as loss of protein, increased drought, increased floods, acidification of oceans...

Chek:You can throw as much mud as you like,but what I dont see is a credible refutation of my analysis.

Jakerman:It said 'counteracted',not eliminated.And "Co2 effect per se will normally be positive"
The numbers from Amthor and my analysis stand.

Lotharsson:So can you put some numbers to these "stochastic influences"that you speak of,or is it just pure conjecture?I have provided REAL DATA,while you and Jeff Harvey have provided us with nothing but arm-waving.Please back up your assertions!

You are a blind denialist warren numbers fall completely over given that:

>*Usually, modest warming (1â4°C) counteracted positive effects of doubled [CO2] on yield.*

How mush do they counter act? So much that:

>*Combinations of rising temperature, [CO2], and [O3] may result in positive or negative effects on wheat yield*

Even though *the [CO2]-effect per se will normally be positive*, the Combinations of rising temperature, [CO2], and [O3] may result in positive or negative effects on wheat yield.

Keep digging warren.

[Warren said:](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) "Chek:You can throw as much mud as you like, but what I dont see is a credible refutation of my analysis".

That wasn't throwing mud Warren, that was putting your 'analysis' (aka some advocacy site's hand-picked cherries) into context. What you're repeating are figleaves of selective data designed to give a political stance the appearance of being something other than what it is. Almost as if providing more CO2 is a public service to be grateful for.

Nobody is ever going to ask you for your 'analysis' of effects on biological systems Warren, though they might well ask JH or BJ.

SteveC:Just like i keep telling people here,I have never said that CO2 is THE limiting factor in plant growth.It is A limiting factor.Water is A limiting factor.Nitrogen is A limiting factor,along with a hundred other micro-nutrients.But experiments show that increased CO2 boosts NPP.End of story.As for Nitrogen limitation,why do think we have huge fertilizer multi-nationals?Because low Nitrogen is,and has been for a lomg time,A limiting factor in plant growth.My point is that while the natural biosphere will not receive the full benefit of CO2 fertilization,crops should get the full benefit with the increased use of Nitrogen fertilizers.But in any case,the FACE trials generally show increased NPP if nitrogen levels are not deficient.

Another study of Co2 fertilization in White Spruce in Canada.Wang,Chhin,Bauerle [2006].

Jakerman:The Australian contingent at Copenhagen 09 was over 100 people!It cost the taxpayer $2 million.Lovely!I will try track down some names for you.But dont worry,in november,Cancun here we come!Dont forget your flippers and sunscreen.

342 Warren -- "My point is that while the natural biosphere will not receive the full benefit of CO2 fertilization,crops should get the full benefit with the increased use of Nitrogen fertilizers.">/i>

Oh great. More dead ocean to look forward to. That means less fish, and, when you'll be able to get it, higher priced fish too.

In a nutshell: Millions starve to death. What's up? Doesn't that fit with your denilaist mythology?

> So can you put some numbers to these "stochastic influences"that you speak of,or is it just pure conjecture?

So are you admitting they exist - or might, but that you haven't tried to account for them?

That would be a start. Then we could talk further.

Or you can start by reading the Tim Curtin thread which covers some of these issues - as [I advised](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) long ago - [as did others](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

>*The Australian contingent at Copenhagen 09 was over 100 people!It cost the taxpayer $2 million.*

That is your reply [to this](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…)? Epic fail.

[Warren whines](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…):

Please get it through your head that the FACE trials show increased NPP.

Can you not "get it through your head" that the effect seen in a few FACE experiments is rendered moot in light of the other limitations which you yourself have [eventually conceded](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…):

SteveC:Just like i keep telling people here,I have never said that CO2 is THE limiting factor in plant growth.It is A limiting factor.Water is A limiting factor.Nitrogen is A limiting factor,along with a hundred other micro-nutrients.

...and along with further aspects of moisture regime, on top of temperature regime, pathogen attack, herbivory attack, altered soil ecology, interspecific competition, and interplays of these and many other factors.

Increasing atmospheric CO2 will lead directly to changes in each of these parameters, as a consequence of the simple, inescapable physics of greenhouse gas action and/or of the simple, inescapable biology of system dynamics responding to one or more altered parameters. You can put your head in the sand as much as you like, whilst clutching your FACE to your chest, but it doesn't change the fact that your bountiful net primary productivity fable is swept away by the monographic sagas of science that you persist in ignoring.

But experiments show that increased CO2 boosts NPP.End of story.

No, nimrod, it's not the end of the story. See the previous paragraph.

If you disagree, explain with detail and references why none of the other resultant phenomena will not have the impacts on net primary productivity that science indicates.

As for Nitrogen limitation,why do think we have huge fertilizer multi-nationals?

So what happens in a decade or several when Peak Oil bites sufficiently hard that nitrogen fertiliser production becomes a luxury for the wealthy, and a memory for the rest of the world?

My point is that while the natural biosphere will not receive the full benefit of CO2 fertilization,crops should get the full benefit with the increased use of Nitrogen fertilizers.

Oh yeah, stuff the natural environment. It's not as if humanity actually needs a functional biosphere for any good reason...

But in any case,the FACE trials generally show increased NPP if nitrogen levels are not deficient.

Oh, this is interesting! Can you show the work that indicates this?! Perhaps that global nitrogen fertiliser industry is a scam greater than the climate science one!

To conclude (for the moment), I see [your spruce](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…
):

Another study of Co2 fertilization in White Spruce in Canada.Wang,Chhin,Bauerle [2006].

and [raise you a beetle](http://scholar.google.com.au/scholar?q=spruce+beetle+climate+change&hl=…).

And dude â punctuation marks are proceeded by a space. Learn your primary-level English, if for no other reason than to make it less obviously apparent that your educational range is peppered with holes...

warren @342:

Just like i keep telling people here,I have never said that CO2 is THE limiting factor in plant growth.It is A limiting factor.

I said nothing about C being a limiting factor in plant growth at all.

Water is A limiting factor.Nitrogen is A limiting factor,along with a hundred other micro-nutrients.But experiments show that increased CO2 boosts NPP.End of story.

No, NPP is the start. Water is and will increasingly be a significant limiting factor, as will soil formation and soil nutrient status, not to mention all the other interconnected processes, disruptions to one or more of which and the compounded effects of which you repeatedly choose to ignore.

As for Nitrogen limitation,why do think we have huge fertilizer multi-nationals?

Why do you think we have algal blooms?

My point is that while the natural biosphere will not receive the full benefit of CO2 fertilization,crops should get the full benefit with the increased use of Nitrogen fertilizers

Crops or otherwise, N enrichment won't fix increased droughts, floods, extreme weather events, out-of-control bushfire or shifts in producer-consumer relationships. And that's just a small sample of the effects we know about...

Get a grip. Better still, get an education.

Re: my last, just realised I've effectively paraphrased (rather badly) Bernard J's #348.

So, Warren, speak to the organ grinders (Bernard and Jeff Harvey), not the monkey (me). If you can convince them, you get me for free. Give us your best then...

My bad.

I thought warren said:

But in any case,the FACE trials generally show increased NPP if nitrogen levels are deficient.

when he did, in fact, say:

But in any case,the FACE trials generally show increased NPP if nitrogen levels are not deficient.

Mea culpa

However, it doesn't change the strength of the arguments against him.

Bernie claims that Warren was wrong to assert that "in any case,the FACE trials generally show increased NPP if nitrogen levels are not deficient"

It is bernie who is wrong as Melillo and others (Nature 1993) show very comprehensively, including that rising CO2 can be positive for nitrogen. Bernie, your knowledge of the relevant papers has many gaps. Read more and post less.

Lothersson:So you dont have any numbers to back up your claims.How many times have I encountered that on this blog.

Great study BernardJ.Too bad its "results" weren't based on empirical data.What were they based on?Yes you guessed it,"projections","scenarios",and finally[a drum roll please]"MODELS,MODELS,MODELS"!!!!!!

SteveC,you are the one who needs to get a grip son.Typical alarmist fear mongering.No substance to go with it though.

>*So you dont have any numbers to back up your claims.How many times have I encountered that on this blog.*

Very perceptive of you warren, that is if you are thinking about [your own claims](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) that are unsupported.

Warren's numbers fall over completely given that:

>*Usually, modest warming (1â4°C) counteracted positive effects of doubled [CO2] on yield.*

How much do they counter act? So much that:

>*Combinations of rising temperature, [CO2], and [O3] may result in positive or negative effects on wheat yield*

Even though the [CO2]-effect per se will normally be positive, the Combinations of rising temperature, [CO2], and [O3] may result in positive or negative effects on wheat yield.

BernardJ:I would like you to do something for all of us that Lotharrson and Jeff Harvey have not been able to do.You see these two[and others]have been railing on about 'unknown factors'and 'stochastic influences'and all sorts of things that can take away from the positive effect of CO2 on plant life.Your task BernardJ[should you choose to accept it]is to put some verifiable numbers to these panicky claims of doom and gloom.Go ahead.

Joel Arlauskis:Thanks for the heads up on that one.I read another study recently that backs this up-saying that if we do have warmer world,then organic nitrogen fixing will increase,given that N fixation is temp dependent.

[Warren doesn't like models](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…), he prefers to cherry pick [the parts of studies](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) that he likes, rather than integrate complex information in a manner that factors in multiple variables.

Jakerman:So CO2 has a net benefit until you add Ozone[nothing to do with CO2]or rising temperature[still nothing to do with the fertilization effect of CO2].And if you are wanting to connect CO2 and warming,then that is the central point of the AGW dispute.

Jakerman:So CO2 has a net benefit until you add Ozone[nothing to do with CO2]or rising temperature[still nothing to do with the fertilization effect of CO2].And if you are wanting to connect CO2 and warming,then that is the central point of the AGW dispute.And allow me to draw your attention to this little word,..."MAY result in postive or negative effects".But the stong positive effects of CO2 have already been posted in #330.

Jakerman:So CO2 has a net benefit until you add Ozone[nothing to do with CO2]or rising temperature[still nothing to do with the fertilization effect of CO2].And if you are wanting to connect CO2 and warming,then that is the central point of the AGW dispute.And allow me to draw your attention to this little word,..."MAY result in postive or negative effects".But the strong positive effects of CO2 have already been posted in #330.

Jakerman:Even if I did cherry-pick,the numbers are still correct and the analysis still stands.You certainly haven't refuted it.

> So you dont have any numbers to back up your claims.How many times have I encountered that on this blog.

Wow, warren - you don't comprehend what I write, and you don't even follow the pointers I provide, then turn around and claim I haven't provided any evidence!

> ...or rising temperature[still nothing to do with the fertilization effect of CO2].

Except that rising temperature is an effect of CO2 itself.

> And if you are wanting to connect CO2 and warming,then that is the central point of the AGW dispute.

There's an uncertainty range for how much and how fast but there's no serious scientific dispute that CO2 causes rising temperatures.

Heck, even Roy Spencer agrees.

Lotharrson:CO2 should in theory cause warming in the world,but we dont know how much.We dont know how the system works.

Warren said:

I dont (sic) know how the system works.

There I have corrected it for you Warren.

A pathetic cheapshot Ian.Try again and use some science next time.

Joel Arlauskis (is this a sockpuppet for Warren since google does not produce any hits for "Joel Arlauskis"?) said:

Bernie claims that Warren was wrong to assert that "in any case,the FACE trials generally show increased NPP if nitrogen levels are not deficient"

It is bernie who is wrong as Melillo and others (Nature 1993) show very comprehensively, including that rising CO2 can be positive for nitrogen.

Joel has obviously never read, or cannot understand simple English since the paper by Melillo says:

In many northern and temperate ecosystems, NPP is known to be limited by the availability of inorganic nitrogen in the soil. Because of nitrogen limitation, TEM predicts that these ecosystems have low capacity to incorporate elevated CO2 into production. In nutrient limited systems, the response of plant growth to elevated CO2 is often constrained under conditions of low nutrient availability.

It seems you are lacking in comprehension skills Joel. It pays to read the actual papers rather than just trust what denier sites say.

Warren, people like you only deserve cheap, but honest, shots. Try harder to learn some science and perhaps become a little more honest in your comments.

Ian you are an idiot!Let the adults talk.

371 warren -- "Ian you are an idiot!Let the adults talk."

Does that mean you'll STFU now?

>*Even if I did cherry-pick,the numbers are still correct and the analysis still stands.You certainly haven't refuted it.*

Says more about you that I could say in a thousand words. Keep Digging Warren your really expose yourself quite adequately.

For anyone late to party, Warren says

>*I have repeatedly pointed out to Jeff that the increase in total biomass makes up for any decrease in protein.In fact it more than makes up for it.The study by Bloom[2010] did in deed show a -11% change in protein concetration in wheat.But Amthor[2001] did a review of 24 outdoor studies that showed that under a doubling of CO2,the yield increase in wheat was 31%.That means that while protein concentration is decreased,the total amount of protein is greatly increased.*

But it turns out that the numbers warren cherry picks do not account for changes in temperature and are derived from tests where plants have ample water.

Warren's math falls apart completely by [simply factoring in a temperature change and O3](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) (let alone other factors).

But for warren this means nothing. Of coarse this is consistent as warren shtick is to cherry pick parts of findings that he likes and ignores the parts that conflict with [his beliefs](http://scienceblogs.com/deltoid/2010/08/open_thread_53.php#comment-2774…).

> CO2 should in theory cause warming in the world,but we dont know how much.We dont know how the system works.

Understanding "how the system works" is not a binary thing, warren. We know quite a bit about how the system works, and - despite the fact that you consistently dodge the point - we have good reasons for believing that equilibrium climate sensitivity is unlikely to lie outside the uncertainty range cited by the IPCC.

So arguing that "we don't know how much" is disingenuous. But worse still is arguing out of one side of your face that "we don't know how much" and out of the other side that "therefore more CO2 will be good for agriculture". Those two statements - if taken on face value, as you seem to want them to be - are mutually exclusive.

But you knew that already, or should have if you'd been paying attention.

Warren writes:

>*Ian you are an idiot!Let the adults talk.*

lol, I see Warren is suffering delusions of adequacy.

[Joel Arlauskis](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

Aside from the fact that you appear to have completely missed [my correction directly above your post](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…), I am very much aware of the Melillo paper, and of the nitrogen limitation literature. In fact, I have folders full of references on this subject, so my reading isn't nearly as sparse as you seem to think.

The thing with Melillo's et al suggestion that organic nitrogen responds in a proportional way with atmospheric CO2 is that it is not entirely supported by recent empirical data. There is certainly an initial direct relationship in many circumstances, but in these cases the experimental systems were not nitrogen-deficient, as has been the point discussed above by myself, Jeff Harvey, Lotharsson, SteveC, Ian Forrester, J Bowers, and others.

Moreover, in systems where there is a progressive increase in organic nitrogen, initially it is usually a result of shifting nitrogen partitioning from soil to vegetation, and depending on replenishment and loss factors such a reallocation may not be maintained over the long term. The two main ways of naturally adding new nitrogen to an ecosystem are through precipitation containing atmospherically-derived oxide of nitrogen, and through bacterial nitrogen-fixation. The first would likely decrease if rainfall decreases, and the second requires that the microbial milieu remains favourable under any future combination of biotic and abiotic parameters. Conversely, nitrogen loss may occur through leaching or through denitrification, both of which might be increased if there are more extreme precipitation events occurring in an ecosystem subject to climate change. Temperature increase could also exacerbate these modes of nitrogen loss under appropriate circumstances. And then there's export by human's and/or emigrant fauna species...

As I said, there are many studies that indicate that progressive nitrogen limitation is a distinct possibility in many systems. Johnson, Gill et al, Hungate et al, and Finzi et al spring to mind â they were all published a few years back in a special issue of Ecology covering this exact subject. When I have access to my files or my other computer I'll find the issue reference, if you can't locate it yourself.

The interesting thing is, that as much as each of these papers emphasises the necessity to expand how carbon fixation is determined in an atmosphere with rising CO2, they do not mention how pathogens, herbivory, or human uses will modify primary productivity. This is the point that I am others here are trying to make. Just how such additional parameters might positively or negatively impact productivity is entirely dependent upon the particular contexts, but again, that's the point of what we have been saying.

[Warren](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…):

Great study BernardJ.Too bad its "results" weren't based on empirical data.What were they based on?Yes you guessed it,"projections","scenarios",and finally[a drum roll please]"MODELS,MODELS,MODELS"!!!!!!

Erm, [I linked](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) to [hundreds of studies](http://scholar.google.com.au/scholar?q=spruce+beetle+climate+change&hl=…), many based upon empirical data. Unless you are referring to something else entirely, you appear to be very confused...

...as you must be when [you say](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…):

Joel Arlauskis:Thanks for the heads up on that one.

Melillo et al used "process-based terrestrial ecosystem models" and "general circulation models". So which is it â do you trust models, or do you not?

And seriously... do yourself a favour and learn to punctuate with spaces. You're only reinforcing the impression of your semi-literacy otherwise.

CO2 should in theory cause warming in the world, but we dont know how much. We dont know how the system works.

This comment from Warren reminded me of that old joke:

The Lone Ranger: It looks like we're surrounded by thousands of Apache warriors!

Tonto: What do you mean "we", white man?

Warren:

How does an increase in biomass with a concomitant decease in protein make up for an increase in C-based foliar phytotoxins?

It doens't, and therein lies the rub.

How many bloody times must I discuss this only for you to ignore it? And why do you also ignore the inevitable non-linear effects on foodwebs?

To those reading this thread: speaking as an insider, the scientific community by and large does not take this 'C02 increases will benefit nature and humanity' nonsense at all seriously. Sure, it is peddled by a few contarians and anti-environmental web sites, but trust me, neophytes like Warren are farting in the wind. We are wasting our breath on this topic, as most ecologists working with plants would never make such an asinine claim as to the benefits of increasing C02 concentrations in the atmopshere, given the massive number of unknowns. But I have said this time and time again, and Warren then retreats to his closet studies and the crap wheeled out by what I assume to be his hero, Arthur Robinson.

When Warren writes, *Ian you are an idiot! Let the adults talk*, he surely cannot be referring to himself, given that he ignores the many points I have made with respect to ecological complexity that he is singularly unable to address. Pure hypocrisy.

New study by Ros Gleadows in Plant Biology:

http://www.biolsci.monash.edu.au/staff/gleadow/docs/gleadow-2009-cassav…

From the abstract:

We found that total plant [cassava] biomass and tuber yield (number and mass) decreased linearly with increasing Ca. In the worst-case scenario, tuber mass was reduced by an order of magnitude in plants grown at 710 ppm compared with 360 ppm CO2. Photosynthetic parameters were consistent with the whole plant biomass data. It is proposed that since cassava stomata are highly sensitive to other environmental variables, the decrease in assimilation observed here
might, in part, be a direct effect of CO2 on stomata. Total N (used here as a proxy for protein content) and cyanogenic glycoside concentrations of the tubers were not significantly different in the plants grown at elevated CO2.
*By contrast, the concentration of cyanogenic glycosides in the edible leaves nearly doubled in the highest Ca*. If leaves continue to be used as a protein supplement, they will need to be more thoroughly processed in the future.
With increasing population density, declining soil fertility, expansion into marginal farmland, together with the predicted increase in extreme climatic
events, reliance on robust crops such as cassava will increase. The responses to CO2 shown here point to the possibility that there could be severe food
shortages in the coming decades unless CO2 emissions are dramatically reduced, or alternative cultivars or crops are developed.

[Italics mine]

Another study by Gleadows in Journal of Chemical Ecology (2009).

From the abstract:

We grew Trifolium repens communities at ambient and approximately twice-ambient CO2 in a controlled environment greenhouse experiment. *We found that the ratio of total cyanogenic glycosides to total protein ratio was nearly two times higher in leaves of T. repens grown at elevated CO2*. This study highlights the importance of assessing the nutritive value of this and other plants in response to rising CO2 so that steps can be taken to address any adverse consequences for herbivores.

[Again, italics mine]

Exactly what I was saying. Cyagenic glycosides are anti-herbivore/pathogen defense compounds. Given the dearth of studies available (it appears that the FACE studies do not explore this area), its certainly very plausible that plants with C-based allelochemistry will increase their levels of secondary metabolites as C02 concentrations increase. This is hardly surprising.

Debating Warren is trying to win a pissing match with a skunk. His strategy is to say that if we do not have any complete and thorough data alluding to the effects of C02 increases on complex systems, then the problem does not exist. It is a strategy that has been used by anti-environmentalists in the past to downplay the effects of habitat loss on extinction rates, acid rain, and other anthropogenic changes to natural systems. Of course, to fully elucidate the effects of C02 on broader ecosystems and communities would require many billions of dollars: never to be funded. Given the fact that unraveling the numerous factors regulating rules of ecosystem assembly and function are only being investigated now and that we have a long way to go, it is clear that we will only have the data Warren demands when it is too late to do anything about it.

My point is that there will be strong ecological consequences if humans continue to use the atmosphere as an open sewer for C02 emissions. And given that some species will do better than others under this scenario, and others worse, it does not require much intelligence to understand that food webs will unravel in synergism with other human-induced stresses to natural systems. The ultimate extinction is the extinction of ecological interactions, as ecologist Daniel Janzen once said. Plants and consumers depend upon each other in food chains exhibiting feedbacks of variable strength. Speaking as an ecologist whose research involved trophic chains, I am very critical of anyone who would claim that tampering with the atmopshere is a good thing for nature on the basis of the vast number of unknowns combined with what we do know about what happens when links in food webs are weakened or eliminated.

Humans cannot effectively manage systems whose functioning we barely understand. Warren and his ilk make the comments they do because they do not have a basic grounding in the field of ecology. Its like someone who knows nothing about medicine claiming that its OK to use a new drug that has hardly been tested but which we know might have adverse effects in the longer term. As I said in my last post, the major solace is that the scientific community is not listening to the shills and laypeople like Warren on this topic. It is a no-brainer. We know there are enormous risks, and on this basis most scientists wil always adopt a very precautionary approach to this aspect of global change.

> And seriously... do yourself a favour and learn to punctuate with spaces.

For some reason that reminds me of someone else who was fixated on the wonders of more CO2 for human agriculture via NPP increase and was not above using sockpuppets. Can't elucidate why though.

[Lotharsson](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

They do share idiosyncratic similarities, don't they? I won't make explicit reference to these similarities though, lest future sockpuppetry is improved beyond the natural scope of the puppeteer.

> His strategy is to say that if we do not have any complete and thorough data alluding to the effects of C02 increases on complex systems, then the problem does not exist.

Indeed. If he quotes some data of the beneficial effect of one parameter under one set of circumstances on one crop, then unless and until you have data for the effects of all the other parameters influenced by the first, **those effects do not and can not exist**.

> Warren and his ilk make the comments they do because they do not have a basic grounding in the field of ecology.

I dispute that.

Warren and his ilk make the comments they do because their goal is to *reach a pre-conceived result*. Furthermore...they don't have a basic grounding in ecology and refuse to get one because that would *hamper their goal*.

And while we're speaking about warren who asserts a government-funded gravy train for scientists who somehow go along with AGW even if they don't think it's accurate, some food for thought from Scott Mandia (who comments here from time to time):

[Taking The Money For Grant(ed), Part 1](http://profmandia.wordpress.com/2010/03/11/) - in which, amongst other things, an example of a grant is broken down into line items including labor costs. Go check out the **huge** sums the gravy train is providing to line researchers' pockets!

[Taking The Money For Grant(ed), Part 2](http://profmandia.wordpress.com/2010/03/22/) - in which it is shown that (for example) US government grant money cannot make faculty rich because of government rules. And it quotes another commenter:

> Go to a local public research university. Find the faculty parking lot. Drive around and count the Mercedes and other luxury cars. Count the fuel efficient economy cars. That should give you a good idea of what is really happening.

> I drive a Chevrolet Aveo with 140,000 miles on it.

and says:

> Apparently, the most famous climate scientist on the planet, Dr. James Hansen, is still driving a ten-year old Volvo!

Jeff, wake up, Ros Gleadow is an ARC charlatan, just like a Paki bowler she will say whatever to cash in.

Lotharsson:There have been hundreds of studies on the CO2 fertlization effect.See Kimball 1983.And your saying that I am have pre-concieved notions?How about you back up your doubts with some numbers.

Jeff Harvey:The Gleadow study is interesting.I believe that it is contaminated science.Firstly it was funded by the Finkel Foundation,which is well known for advancing left-wing enviro greenie causes.[EG The magazines COSMOS and G].Secondly it's claims about reduced yield go against hundreds of other studies confirming the CO2 fertilization effect.It basically stands alone in this regard.Third,it's claims about tuber yield decrease are completely refuted by the findings of Imai[1984]on cassava grown at elevated CO2.Dry matter production was increased by 54% for low temp/high CO2,and by 150% for high temp/high CO2.Every metric for cassava growth was increased under high CO2 in this study.

> And your saying that I am have pre-concieved notions?

Comprehension fail. A pre-conceived goal is NOT the same as "pre-concieved notions".

Lotharsson:I have never said that scientists or others on the gravy train acrue PERSONAL wealth through their funding,which is what you are trying to insinuate.I said they get to enjoy the PERKS because of the explosion in funding for this new "industry".

> How about you back up your doubts with some numbers.

How about **you** do some investigation into the factors that the professionals have been telling you *matter*, and which you foolishly dismiss or treat as having no impact? You could start by ceasing to ignore the papers cited to Tim Curtin on his thread when he made similar claims to yourself.

> There have been hundreds of studies on the CO2 fertlization effect.

Indeed. The biologists and ecologists seem well aware of it - including the very same ones that are urging strong caution with regard to increasing atmospheric CO2, because of the likely negative impact on agriculture and the ecosystem as a whole.

And you have been told a dozen different ways that other factors are quite likely to turn out to be significant, that your fantasies that fertilisation effect will translate directly into agricultural production increases depends on those other effects not having any significant impact, and that you dismiss those other effects or assert without evidence that their impact will be negligible.

In other words, your preconceived notion is that the data you cite extrapolates to actual agricultural production and ecosystem health in a higher-CO2 ecosystem.

I doubt anyone can get it through to you how thoroughly unjustified and naive your claims are.

> I have never said that scientists or others on the gravy train acrue PERSONAL wealth through their funding,which is what you are trying to insinuate.

On Open Thread 53 you used language that would have implied to most readers that scientists were accruing personal wealth:

> And scientists on the government gravy train are going to say,"look guys we really dont have a problem"???Yeah right!

"Gravy train" generally means personal benefit, typically in the form of wealth or possessions - so it's good to see you're really talking about "perks" (which aren't perks) such as travel for work.

However, in that case your assertion that they're toeing some imagined party line on AGW merely to get the perks completely crumbles. Who is going to earn (say) $40-100k/yr less than they could - year after year - in the hope that they rise high enough in their field to score a government-funded economy class ticket to a conference every now and then - and to which they could more than comfortably pay their own way out of the extra earnings if they went to industry? That simply fails as a motivation, especially as a motivation strong enough for them to implicitly or explicitly endorse something they do not believe to be true. Especially when they are *scientists*.

warren -- "I said they get to enjoy the PERKS because of the explosion in funding for this new "industry"."

Tracking U.S. Climate Science Funding
"U.S. government spending on climate research reached a peak of $1.9 billion in 2004, then entered a period of steady decline before picking up slightly after fiscal year 2006."
http://newsinitiative.org/story/2008/12/13/tracking_climate_science_fun…

If you want to see really big funding in the past from the taxpayer though, look no further than Lindzen. I mean a serious wad of cash over the years.

> I said they get to enjoy the PERKS because of the explosion in funding for this new "industry".

Even that embodies an incorrect assumption.

A heck of a lot of the funding is for studying (a) the climate system and (b) climate change and its impacts and mitigation methods, **regardless** of how much climate change is due to anthropogenic causes versus other causes. Why? Because that knowledge is just as valuable to us **either way**.

> I mean a serious wad of cash over the years.

Sheesh, it almost makes you wonder if Lindzen is toeing a party line on climate science that he doesn't necessarily agree with - merely so that he can continue to ride the "gravy train" ;-)

Warren has proven his complete and utter disregard for science by dismissing two peer-reviewed studies on the basis that, as Lotharsson said yesterday, do not fit in with his pre-determiend worldview. Do you know anything about allelochemistry Warren? Anything at all? Because Gleadow's results are hardly surprising. If concentrations of carbon increase in plant tissues, then why would we not expect plants to increase their allocation of carbon to C-based chemical defense compounds? You write as if plants like being eaten, as if they evolved for the benefit of vertebrate and invertebrate herbivores and pathogens. On the contrary, plants have evolved all kinds of chemical and morphological defenses to avoid being eaten. Herbivory carries enormous fitness related costs to many plants (something I am current researching). Most plant species produce a veritable armory of chemical compounds to resist herbivores, including proteinase inhibitors, phenolics and phylogenetically conserved toxins that are N or C-based. Every plant biologist knows this, even if the ignoranti deniers don't. All Gleadow's research has done is to confirm the obvious. More atmospheric carbon = more carbon allocated to phytotoxins in plants with C-based allelochemistry = lower plant quality for herbivores. Hardly controversial, with the exception of people like old Warren and his acolytes.

Thus, to call Gleadow's research 'contaminated science' goes beyond the pale. Simply put, anti-environmentalist right wing libertarians like Warren, most of whom have trouble telling a mole cricket from a giraffe, seem to think that they innately possess the wisdom to disregard sound science (e.g. any old anti-environmental rubbish that downplays a range of anthropogenic threats) from junk science (e.g. any studies, no matter how rigidly peer-reviewed and irrespective of the soundness of the journal in which they appear). Of course, this is based entirely on their own personal biases, and not on science; no matter how much empirical evidence accrues showing Gleadow's research to be merely the tip of an iceberg, we can count on denialists like Warren to come up with any old excuse to downplay their research. But the good news, Warren, is that scientists do take notice of the research you appear to hate. You can bet that Gleadow's articles will be heavily cited in the empirical literature.

Lotharsson also completely debunks more of Warren's nonsense in post 389. The most important point is that scientists, INCLUDING MYSELF (capitals for Warren's benefit) have known about the fertilization effect for decades. But we also know that the effects of C02 on ecological communities are not simply linear. We know that different species of plants will respond in an association-specific manner to C02 increases, and that there will be all kinds of other potentially nasty effects, as Gleadow has pointed out, on ecophysiolgical plant traits that are context- and trait-dependent. And these effects will ripple through communities and ecosystems.

Note that most of the authors of the studies Warren brazenly cites as evidence for his wafer-thin arguments express immense caution as to the effects of C02 fertilization on communities and ecosystems. They do this because they are aware of how much we do not know. Some of those articles I discussed earlier in the thread, showing what the scientists themselves had written, and how they admitted that we know very little, if anything, about the effects of this 'experiment' on complex natural systems. As is his wont, Warren disregards this caution and goes for the straight ahead approach, typical of those who are NOT scientists.

Warren's tactic, if one can call it that, is to simply highlight a few studies examining step one of a process while downplaying the array of unknown effects on steps 2 through 100 of the same process. When I have repeatedly debunked his nonsense, in true contrarian style he has ignored the meat of my criticisms and continually retreats back to step one (bearing in mind the effects of C02 increases on steps 2 through 100 - representing an increase in spatio-temporal scales are unknown). Pure guesswork. And many seriously potentially negative effects.

As for the Tim Curtain post, I assume it is a sock puppet for Tim Curtin or a joke at Warren's expense.

Further to [my reference to the Ecology issue about nitrogen in primary productivity](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…), the contents page can be found [here](http://www.esajournals.org/toc/ecol/87/1).

Warren, as a child were you beaten behind the sheds by a nasty space? You seem to have a pathological aversion to spaces these days...

And seriously, lose the conspiracy theory. You have no clue at all about what motivates a research scientist. It certainly isn't 'perks'. If it were, I'd personally choose any of my friends' jobs rather than my own - that way I'd be off to Asia or Africa once every two months, or I'd be dining out or going to sporting events or to the theatre once a month, or driving work-funded vehicles for my personal use, all as perks of their corporate jobs.

In fact this year alone, and largely against my personal inclination, I have met one govenor, sat to dinners with two mayors on separate occasions, and hobnobbed and/or dined with a number of CEOs, state politicians, sporting stars and sundry other high-falutin' personages because my friends have so many spare corporate perks to go around...

And yet, as a scientist I have to put 50 cents into the jar when I make a cup of tea from material in the communal tea room.

Yeah, perks alright...

You have no clue at all.

> ...all as perks of their corporate jobs.

That's the most amusing thing.

warren's argument - that perks mean that scientists will endorse something they don't think is supported by the evidence - applies **in spades** to scientists in the pay of industry. Not only do they have much better perks, they have much better salaries to protect to boot.

So warren's logic means that warren must reserve a double dose of skepticism for any position held by scientists who derive perks and/or income from industry. And yet, strangely enough, I don't see warren campaigning against those particular positions on that basis. Hmmm.........

Jeff Harvey:As well,what must be remembered is that the food value part of the cassava plant is the root.Increased root yields will mean that the leaves will not be needed as much as a protein supplement.Cyanogenic glycosides are not increased as a whole,they are only increased as a RATIO to protein in the leaves.Given the demonstrated large increases in tuber yield[Imai 1984,1985]from CO2 fertilization,the doomsday forecasts of Gleadow have no scientific basis at all.The language she uses in that paper also smacks very much of AGW ideology.

Anyone else get a laugh at Warren's pathetic attempts to list references?

Do you just make them up Warren or are they real and you are too lazy to give a complete cite? Or do you just cut and paste them from denier sites without even reading them?

You are so pathetic.

Jeff Harvey:I did not dismissed both studies Jeff,just the one on Cassava plants,and with good reason.Now would you like to respond to the findings of the Imai[1984]study?Why do I even bother asking,I know you wont!In regards to the second Gleadow study to do with clover[TRIfolium Repens],I am working on it.

To all and sundry:Some scientists are more equal than others,that is why Penny Sackett,Ian Lowe,Tim Flannery and a stack of other scientific invertabrates get to go to Bali and Cancun and Bangkok and stay at swank hotels,eat at swish restaurants etc;all on the taxpayers creditcard.It almost makes me want to change my tune.

To all and sundry:Some scientists are more equal than others,that is why Penny Sackett,Ian Lowe,Tim Flannery and a stack of other scientific invertebrates get to go to Bali and Cancun and Bangkok and stay at swank hotels,eat at swish restaurants etc;all on the taxpayers creditcard.It almost makes me want to change my tune.

JBowers:So how much money did Lindzen make?I might just go out on a limb here and predict that all you have is an accusation and not a verifiable number.If you prove me wrong,then I will wear the inevitable redicule.

warren asks:

So how much money did Lindzen make?I might just go out on a limb here and predict that all you have is an accusation and not a verifiable number.

Here is your answer:

Lindzen, for his part, charges oil and coal interests $2,500 a day for his consulting services; his 1991 trip to testify before a Senate committee was paid for by Western Fuels, and a speech he wrote, entitled "Global Warming: the Origin and Nature of Alleged Scientific Consensus," was underwritten by OPEC.

Mmmm $2500 per day (in 1995 $$'s) sounds pretty "perky" to me.

Too bad Tim doesn't have a video feed, since warren said:

If you prove me wrong,then I will wear the inevitable redicule (sic).

Though I'm not sure how much more ridiculous warren can be after all his asinine comments on this blog.

http://dieoff.org/page82.htm

Well done Ian,you half got me.The Gelbspan article is wrong.Lindzen did not charge consultancy fees.They were expenses and expert witness fees.Also it was back in the early 90's,so it is a little out of date.Still,I dont want to rob you of your bulls-eye.

warren you are a dishonest, pathetic old man. I didn't "half got me" I got you as a 100% dishonest denier.

How come when a scientist gets his way paid to a meeting (usually steerage) then it is a "gravy train perk" yet $2500 per day is an "expense"?

You are so dishonest, keep up the good work you are showing just how dishonest you deniers are.

Ian:It's a gravy train because of the numbers.More than $50 Billion on climate research,and that is an old number.15,000 delegates at Copenhagen,all at public expense.And on it goes.This is absolutely no comparison with the money the sceptical side gets.

Science ofcourse is very cheap.But there is one guy going around the AGW lecture circuit,and I have heard that he charges $175,000 for a 30 minute speech.That makes him 70 times more valuable[scientifically speaking]than Richard Lindzen.

["Warren" said:](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) "More than $50 Billion on climate research,and that is an old number.15,000 delegates at Copenhagen,all at public expense. And on it goes".

So those are your claims. Can we expect some evidence for them?

To make it easier for you, I'll accept your breaking that $50 Billion down to the nearest $10 million per item.

Shorter Warren $2,500 per day (in 1995 = PV of $3,900 in 2010) of Lindzen providing 'service' to fossil fuel industry lobbies, [is an expense](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) but money spent of climate [research](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) (satellites, ARGO system etc) that is a gravy train.

Warren, Fossil fuel companies are spending our wealth via liquidation of natural assets. And they are spending profits gained from selling our natural assets to fund election campaigns, lobby groups, think thanks, and Lindzens. All with the aim of slowing efforts to align economic feedbacks with environmental feedbacks.

Oh yes and a [little reminder](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…), of something Warren did not reply to.

> More than $50 Billion on climate research,and that is an old number.

Is argument-from-personal-ignorance all you've got, despite having been corrected earlier?

Most of that budget is for satellites and other research, which we want to do **regardless of AGW or no-AGW** because we are highly motivated to understand the climate system. You know, because if natural variation is changing the climate we'd kind of like to know how, how much, and what to do about it?

> 15,000 delegates at Copenhagen,all at public expense.

As I've pointed out, these were expenses of *politics* and attendees were mostly politicians and civil servants. It fails to support your argument that *climate scientists* as a whole discipline generally distort their scientific positions in order to (say) go to a conference like Copenhagen.

If you can't see that the difference between what you wrote and reality makes your arguments fall, you should not be making them.

> It's a gravy train because of the numbers.

That's just a plain stupid assertion. If the numbers for any area of endeavour get big enough, by [your] definition "it's a gravy train"?!

> But there is one guy going around the AGW lecture circuit,...

Ah, so warren in desperation falls back to talking about a non-scientist. Hard to see how the example of a *non-scientist* supports his claim that scientists privately think AGW is bunk but don't say so publicly because they are "riding the gravy train".

But it was already hard to see that because the gravy train in question means earning half of what they could elsewhere.

warren's argument is pathetic.

Warren:

I will not even get into your discussion of 'gravy trains' because it is utterly pathetic. Other posters here have demolished it. I wonder how much you decry the 'military industrial' gravy train, which is gigantic by comparison and which results in the death of millions every year.

As for the 1984 study, as I said before, I accept the results of closed studies conducted under mostly limited abiotic conditions that have reported an increase in plant biomass with increases in C02. But Gleadow's work is important for a number of reasons. Most important of these is that she has definitiely shown that plants with C- based alleleochemistry respond to higher levels of atmsopheric C02 by allocating more allelochemicals to plants shoots, concomitant with a decrease in foliar protein levels. This means that foliar herbivores will have to ingest more plant biomass to accrue to same amount of protein as before, but at the same time they will ingest considerably more plant toxins. It does not matter what the heck humans eat - nature functions on the basis of a stupendous array of interactions involving plants, herbivores, pathogens, predators and the like. If Gleadow's results are extrapolated across food webs and communities, then we have a very serious problem.

Your intellectual island, never much to begin with here, is shrinking into oblivion. Your latest attempt to dismiss the results of research that you do not like is to either (1) belittle the messenger, or (2) ignore the repercussions beyond narrow parameters (root biomass) that you set. You therefore ignore the potential significance of the atmospheric experiment being conducted by humans on ecological communities and interaction network webs, and ultimately at larger scales on ecosystem functioning, mediated at smaller scales through profound changes in plant quality as a result of species-specific responses to increased C in plant tissues.

If many plants with C-based allelochemistry invest much of the extra carbon for secondary toxic metabolities (and there is no reason to believe that many species will not), whereas species with N-based allelochemistry become potentially less toxic, then there will be all kinds of serious ecophysiological and phenological consequences. As I have said many times here, and it apparently has not sunk into your head, humans are not exempt from the laws that govern the existence and survival of other species. Tampering with complex adaptive systems will inevitably lead to changes in the way they function, with the worry that critical ecosystem services freely emerging from nature that sustain humanity will break down.

Your last feeble riposte shows to me that your arguments have run their course here. We are back to downplaying or ignoring large scale effects of C02, and are back to your discredited "Plant species 'x' grows bigger with more C02 circulating in the atmosphere, and thus its a good thing!". Gleadow's results go well beyond the implications for cassava or clover. That is why her articles are being published in sound journals like Plant Biology and Journal of Chemical Ecology.

One question I would like to ask you, Warren: what exactly is or was your profession?

warren,

Awesome to read your statements that:
303:
>"elevated CO2 was responsible for plant extinctions"

307:
>"elvated CO2 led to the extinction of plants"

313:
>"High CO2 made plants go extinct"

315:

>"CO2 made plants go extinct"

Great to see you contemplating alternative points of view!

363:
>"I did cherrypick"

Yes you did.

385:
>"I have preconcieved notions"

Yes you do

402:
>"you prove me wrong".

Yes we do.

Since you're happy quoting Schneider in such a fashion, "excising", [as you say](http://scienceblogs.com/deltoid/2010/09/steven_schneider_and_the_skept…), those parts that you consider the "important pieces", I trust you won't mind if I read your posts in the same way and quote you accordingly.

A study by the CBO found that spending on climate change work between 1998 and 2009 was $99 Billion[2009 US dollars].Wales spent $5 million in just 3 years.Australia $2.3 Billion over 3 years.The gravy train lives!

> The gravy train lives!

Now that we know when you say "gravy train" you mean ["big numbers that impress me"](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) rather than as originally implied "scientists personally getting rich by refusing to disprove AGW" - and certainly [not "easy money for scientists to endorse industry positions without solid scientific backing"](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) - ...then these numbers and your comment reveal more about your personal incredulity than anything.

warren,

What is your view on fearmongering in order to procure extra defense spending? Have you compared the numbers?

Jeff Harvey:I am a science teacher.

MFS:Were you hatched from a moron egg?If not,then enough of the childishness.
"fearmongering in order to procure extra defense spending?"
It should be condemned,and the perpetrators prosecuted if possible.

Lotharsson:Most research on climate change goes into studying the EFFECTS rather than the causes,and this is valid science.But it is still a gravy train because of the vast increase in the funding available.And will you please cut the crap about scientists getting personally rich.I never said it or implied it,so knock it off.

Jeff Harvey:I wish you would not make statements like, "results in the deaths of millions every year." You know that it is an absurd thing to say.You also know it is utterly wrong.Be a scientist Jeff,be factual.
The Gleadow study does show an increase in foliar toxins,and this is a good thing.Lower herbivory means less loss of photosynthetic potential.More yield for the culivators.As for herbivores,under CO2 fertilization,almost all other plants will have their yield increased,therefore a large increase in the food stock for herbivores.Also cyanogenic glycoside producing plants are only around 10% of the total are they not?[I think that number is accurate]The % may be higher for grasses.Therefore cant herbivores generally select alternative herbage if some are higher in toxicicity?

> And will you please cut the crap about scientists getting personally rich.

I've acknowledged that, and continue to do so - so I fail to see how I am spreading "crap".

Perhaps you should cut the crap about "gravy train", which (a) implies "personally getting rich" to most readers, and (b) is NOT commonly defined as "because there's a lot of funding" or even "a big increase in funding" (most especially not when - as you acknowledge - it's for good valid science).

warren:

I am a science teacher.

God save us.

>*God save us.*

Standards have been dropping for decades.

Warren says he is a science teacher.

Gee, let me just say that I am happy that he did not teach me his brand of 'science', and leave it at that. Given his utterly vacuous remark in response to my comment about overconsumption and foreign policy on the Open Thread, it seems to me that Warren's judgments are seriously compromised by his right wing political views.

As for his response above, well, as all of his others go, it does not cut any ice. But what does one expect with someone like Warren who is well out of his depth on this topic and is trying to extrapolate far too much from studies that support his pre-determined worldview? For one thing, a reduction in herbivory is not necessarily a good thing in natural systems. Period. Less herbivory will have a profoundly negative effect on multi-trophic food webs involving plant mutualists (natural enemies and pollinators), particularly as we know that plant defence traits can work their way up food chains. By altering the stucture of food webs in this way, they are prone to sudden and quite dramatic shifts and are also more prone to collapse. Furthermore, many more plants have C-based defenses that Warren suggests. Many also have N-based defences, and any loss of foliar nitrogen - even relatively small concentrations - as carbon is taken up will certainly lead to effects on herbivores that might go in the opposite direction. Plants with less foliar nitrogen will not only have less N-based allelochemicals, but less N in general, leading to increased herbivore damage as N is the most limiting nutrient for herbivore growth. Some of the studies mentioned in the last video I attached have shown that herbivores are also more attracted to crops grown under elevated C02 regimes and inflict significantly more damage on them than on controls. Research done by a PhD student here showed that there were also all kinds of unpredictable effects of elevated C02 on soil food webs and especially on mycorrhizal fungi. She said in her thesis 'commentary' that those who are pushing the 'C02 is good for nature line' literally have no clue what they are talking about. Again, they are foisting their political agendas off distorting science to do so.

If we take the results of these limited studies that Warren thinks bode well for us all, then what we see are all manner of unknown and unpredictable consequences occurring in a very short time. Unlike Warren, who certainly is not qualified to comment in any depth on the issue of plant ecophysiology, I am, and like most of the scientific community I realize that there are serious risks involved in continuing to pump out copious amounts of greenhouse gases into the atmosphere as if it were an open sewer. Virtually every scientist Warren cites in defense of his shallow views attaches caveats to their work alluding to the vast number of unknown and potentially serious consequences of C02 'fertilization' and attendant climate change. But Warren, showing his true anti-environmental, anti-scientific colors, continaually ignores the warnings and caveats and unknowns and thinks that these can be ignored completely. He thinks that we can take limited results from experiments conducted under either controlled conditions (thus excluding many important biotic and abiotic parameters) or else those conducted in small spatial scales outdoors and use them to explain the global effects. This, while I have already explained, that there are almost certainly to be deleterious effects caused by association-specific responses at the species level and corresponding non-linear effects up the food chain and into broader ecological systems.

Anyone comparing Warren's posts with mine should be able to realize the imposter from the scientist. Like others in my profession, I am cautious and sceptical, given both the results of empirical studies and the vast number of unknowns as a result of the current atmospheric experiment being conducted by humanity. Warren dismisses climate change completely, but contrast that with his complete and utter acceptance of the benefits of C02 fertilization. Note also how he shoots the messenger (e.g. his feeble attempt to downplay the Gleadow et al. studies) in spite of his complete lack of pedigree in the field. Few statured scientists would respond to this issue in this way.

I would love to debate Warren in front of his students. It would be a slam dunk. Utter annihalation. I gave Bjorn Lomborg a serious going over when he came here in 2002, and Warren is a veritable pussycat by comparison.

Jeff Harvey:OK Jeff,you have issued the challenge and I accept it.We will debate.Are you still in the Netherlands?If so then I will arrange to come to the Netherlands,if you can arrange some kind of suitable venue.We also need an audience of say 50 people to make a decision on the winner.Shall we also make it interesting by each betting $500 US on the result?If you agree to those conditions,then I will come to debate you.Do you want to debate climate change generally,or the CO2 topic we have been discussing?

I like where this is going.

>*I like where this is going.*

Given Warren's dishonest approach to date, I'm betting he'll find an excuse to backout.

After getting his hat handed to him here Warren is just trying to save face.

BTW, 50 people willing to stepout to hear Warren's nonsense? [Delusions of adequacy](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) have evolved into delusions of grandeur.

Jeff Harvey"anyone.....should be able to realize the imposter from the scientist." Yes they should Jeff,and do you know how they would do it?They would look at who has cited the most studies,who has given the most numbers,and who has NOT raved on with a whole lot of psuedo-scientific philosophical greenie flim flam.Now I wonder who would emerge as the scientist?

Not you.

[Here is clue](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) as to how acompetent person might distinguish warren's claims from those of a credible person.

Jeff Harvey has cited 10 studies and used numbers 3 times.Warren has cited 18 studies and used numbers 12 times.

Jakerman:Do you know how to do science or dont you?If you want to find out the effect of a variable,you change that variable and only that one,otherwise it is difficult to nail down cause and effect.When CO2 is isolated it's effect on NPP is indisputable.If you want to make conclusions about temp or oxone,then a multi-variable study is done,however the results are then a lot more open to dispute.

No Warren, an imposter is someone who gives the impression that its a simple numbers game, or even more childishly that 'I have cited more studies than you! Nah, nah, nah, nah, nah!".

You teach science? God help us all. You do not have a clue about how science works, and think that a few studies conducted under controlled conditions can explain processes in nature that are many millions of times more complex. You get away with your bilge because you are able to ignore the 99% of the important content of my posts. This is where I say that there are a vast number of unknown effects in complex adaptive systems that will be likely to occur as a result of using the atmosphere as a carbon sewer. Pretty well all of the scientists who write the studies that you cite as proof of the benefits of C02 ferilization would totally disagree with you broader conclusions. In fact, most of them have expressed concern in their work about the vast number of unpredictable consequences that cannot be predicted from their experiments.

Science is about being cautious and sceptical. You are neither. In the face of all of the vast array of unknown effects of increasing C02 in the atmopshere scientists are are of the potentailly hidden consequences. I never denied that many plants will grow larger as C02 increases. But the effects will be highly asymmetrical, and this is of grerat concern. Because you are not a scientist and do not understand basic ecology, your only recourse is to cite a few limited 'knowns' whilst ignoring a far great number o 'unknowns'. In this context you will never win a debate in front of a scientific audience.

So as for debating me, certainly I would do this in front of an audience of 10 or 10,000. I warn you beforehand: you are well out of your depth and you will lose, big time, on the basis of your 'evidence'. My colleagues here would find it comical in the extreme that a school teacher would debate me on this issue. But, yes, I would be happy to arrange it for sometime early in 2010. I will not wager money, just my reputation as a scientist, but I can assure you that your challenge does not in the least bit worry me. Not one iota.

For the debate I mean in 2011. And I would want it in front of an audience of scientists. I would suggest the same format as when I defeated Lomborg here, in 2002. He was a pushover, in my opinion. Warren, you will be easier. You do not know what you are in for. Before you commit to this, think it over. I know that I cannot lose this, on the basis of my knowledge os systems ecology. You would have to seriously swot up on this area, because if you rely on the studies that you have cited here so far, you are in for a shellacking.

I would make efforts for media coverage here, which should not be too difficult.

Jeff Harvey:OK it is on.You arrange it for early 2011,and I will be there.Everyone on Deltoid blog are the witnesses.You did not specify the specific subject area.I would prefer the general area of catastrophic climate change,but if you want CO2 fertilization as the subject then fine.I would insist that we do it for money however,as this gives me some incentive to spend the money getting there in the first place.I am willing to let Tim Lambert hold my $500 US as security if he is willing to do it.I am not afraid to put my money where my mouth is.Media covereage would an advantage.And I know what I am "in" for Jeff.I have debated both David Karoly and Ove Heogh-Guldberg,and I atleast held my own.Compared to them,you have a poor train of logic and you lack evidence for your claims.

"Jeff Harvey has cited 10 studies and used numbers 3 times.Warren has cited 18 studies and used numbers 12 times."

Warren has counted that as using numbers four times...

Warren has not said that his stated studies are correct or even shown that they show what he states they do. About 20 times.

Wow has used numbers seven times.

Ww:Th clnc jst clld,yr brn s rdy!

Well, what can you expect from a teenager, other than whiny angst?

PS when warren complains at an ad hom, anyone can point him to post 437 here, devoid of content as usual.

Why would increased CO2 levels make plants "thrive"? Won't their CO2 needs stay the same due to the fact that the roughly the same level of photosynthesis should be occurring?

Don't human living at high elevations with lesser amounts of O breathe more deeply in order to get the same "molar" amount of O, since they still have to carry out the same biological functions? Why would this be different for plants?

Doesn't the very existence of CO2 in the atmosphere indicate that plants do not currently use all of the CO2 available? Why would increased concentrations mean they would use more?

>*Do you know how to do science or dont you?*

Yes, and you don't, science is the opposite of [your approach](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…).

>*if you want to find out the effect of a variable,you change that variable and only that one*

Thanks for primary school interpretation, an overly simplistic strawman that is a perversion of the debate.

Only fools would assess the threat of AGW by selecting a) only positive studies of the effect of CO2, and b) by excluding effects of temperature, and other factors associated with burning fossil fuels.

BTW Warren, were you being economical when [you said](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…) you only have a:

>*"diploma in medical laboratory science.That is all."*

Or were you being economical when you said you were a science teacher?

Warren is revealing on another thread that arrogance and ignorance [can fit](http://scienceblogs.com/deltoid/2010/05/brent_thread.php#comment-2793137) quite well.

Warren writes:

>*but if you want CO2 fertilization as the subject then fine.*

If you are "debating" a ecologist it makes sense to focus on the field where one of you has professional competence. I'd suggest Jeff take this as the subject for debate.

>*I would insist that we do it for money however,as this gives me some incentive to spend the money getting there in the first place.I am willing to let Tim Lambert hold my $500 US as security if he is willing to do it.I am not afraid to put my money where my mouth is.*

Bull crap Warren, we all know you are full of it. You ain't going to leave your money with Tim. You aren't flying to Europe, you haven't held your own with Jeff even in this thread. Your a just another Dunning Krueger with a big mouth.

I'd smile if you were as good as your word. But you are not. Prove me wrong fool.

Jakerman:If Jeff agrees to the terms[or maybe even if he does not agree],then I will go to debate him.I will allow Tim Lambert to hold my security deposit,that is,assuming he wants to be involved.If Tim were to get involved it would be great publicity for his blog-maybe he could run an online poll in regard to the outcome.It would be a hoot,and I would win the debate easily in front of a group of scientists.Does the idea hold any interest for you Mr Lambert?

> If you want to find out the effect of a variable,you change that variable and only that one,otherwise it is difficult to nail down cause and effect.

Warren, this points to the core of many of your repeated errors (and it's not like you haven't had most of this pointed out over and over again).

Unfortunately only changing one variable is *not possible* in much of science (including most of medicine), so you have to move on from this ideal but simplistic approach in order to deal with more complex scenarios.

The main problem with your statement quoted above is that it is (in most cases) a false description of your argument. For starters you need to be more specific - the vast majority of the studies you are citing are trying to find the **direct** effect of one input variable on **a particular output variable** under a *limited range of conditions* whilst excluding *most* (if not all) indirect effects and excluding *most* (if not all) other output variables of interest.

You make egregious errors when:

a) You focus on the effects on an output variable that is *not directly relevant* to the needs of either humans, or many other ecosystem participants. (It's almost as if you respond to questions about how fuel-efficient your car is by lauding its superior acceleration - and then when others point out demonstrated safety concerns with that model you point back to its acceleration.)

This error alone renders your argument moot. And it persists despite having been schooled over and over again as to why the variables that **are** directly relevant are unlikely to be benefited in the ways that you claim.

b) Assume linear superposition (or something a lot like it) which you appear to do quite frequently, as it is pretty much required if you're trying to determine the effect of one single variable by keeping all the others constant. This means your assumptions exclude the possibility of (as one example) non-linear threshold effects (hit a threshold and suddenly the previously identified relationship changes dramatically). Unfortunately there's plenty of evidence for threshold effects in the ecosystem.

c) In a similar vein there are non-linear multi-variable interactions which are excluded when one assumes linear superposition. It's true that you occasionally cite multi-variate studies (typically only CO2 + temperature), but even then you seem to mentally model it as the superposition of two independent effects. Worse still, whenever other multi-variable interactions are said to be likely to be significant or to need more research you pretend that they simply cannot have any significant negative effects - when there is no evidence to support this assertion.

d) You assert or imply that no significant indirect effects can exist. Studying direct the effect of variable x on outcome A is fine as far as it goes. But if variable x also affects variables i, j and k which ALSO affect outcome A then asserting that the total effect of x on A excludes the effects of {i,j,k} on A is fallacious (especially for one who suggests they are actually interested in determining cause and effect). It only gets worse if some of {x,i,j,k} also affect some of outcomes {B,C,D} which in turn affect some of {x,i,j,k}.

And after having this kind of error pointed out several times, one can draw certain conclusions about those who persist in making it.

e) You extrapolate very limited studies to a much wider range of circumstances (and species) than is warranted. (Never mind that your extrapolation is reliably and dubiously optimistic.)

>*If Jeff agrees to the terms[or maybe even if he does not agree],then I will go to debate him.*

Yes I know you are saying this. Its that I don't believe you in the slightest. Your comments give you away as someone completely empty.

I.e. you claim to have debated other climate scientists, with no supporting evidence, you claim you are a science teacher but you also claim:

>*"I dont mind telling you my qualifications.I have a diploma in medical laboratory science.That is all."*

Which seems inconsistent with being a science teacher.

Are you prepared to take any step that would enhance your credibility or accountability? Any small gesture? I think you are all empty talk.

Lotharsson:I have never said that there are not other variables,nor that there are possible unknown consequences.What I have said is that the data we have to hand shows overwelmingly that elevated CO2 will be beneficial to plant life.That is what the data shows.I have seen very little DATA to contradict that view.All I have seen is mainly speculation.

> I have never said that there are not other variables,nor that there are possible unknown consequences.

As I indicated you have (clearly) implied it. When people point them out to you (as I said) you proceed to dismiss their effects.

> What I have said is that the data we have to hand shows overwelmingly that elevated CO2 will be beneficial to plant life.That is what the data shows.I have seen very little DATA to contradict that view.All I have seen is mainly speculation.

Remarkable.

I and others have pointed you to counter-examples which you pretend do not exist - see your quote immediately above for yet another reiteration.

Furthermore I and others have pointed out that - even based on known data - your definition of "beneficial" is very one-eyed and limited in scope, but you pretend that it is the only definition that matters.

Jakerman:My debate with david Karoly is on youtube.My debate with Ove H-G is on my computer and will soon be on youtube.My diploma in Medical Lab Science is from QUT,I have a BA in Japanese from Griffith Uni,and I did my diploma of education at UNI of queensland.Happy now?
PS Are you willing to stake some money[$100 US]on me going to holland to debate jeff?

Lotharsson:Give up some numbers to refute me-otherwise it is all just polly-waffle.

> Give up some numbers to refute me-otherwise it is all just polly-waffle.

Shorter warren: if I don't read what you refer me to, it doesn't exist.

>*Jakerman:My debate with david Karoly is on youtube*

Should be easy for you to prove then. Back your claim up.

Jakerman:Well you have got me.This is going to cause me a LOT of grief to do this,but I cant back away now.Go to youtube and search The Viewpoint Brisbane.Karoly should be number 2.The debate is in 2 parts

Warren are you Tim O'brien Wells?

>*Go to youtube and search The Viewpoint Brisbane.Karoly should be number 2.The debate is in 2 parts*

Found [the shocking interview by tim obrien wells](http://www.youtube.com/watch?v=qDNfNt_kjtI&feature=related)in [two parts](http://www.youtube.com/watch?v=kU-WbvT3Bag&NR=1) with Karoly, but no debate.

Are you not able to back your claim?

Jakerman:I backed my claim Jake,that is it.

Tim O'brien Wells, so what you claimed was a debate was in fact your interview with Karoly?

> My debate with david Karoly is on youtube.

I assume that I have the right YouTube ([episode2part2](http://www.youtube.com/watch?v=qDNfNt_kjtI&feature=related)), and thus that "warren" is the presenter on this clip...

...which doesn't start out well by claiming that "most of the disagreement" is "centered on the science" as this does not reflect reality. However the video spends a few minutes discussing the politics of GHG reduction agreements - although in doing so the presenter at least appears to acknowledges that we do need something done. However the presenter is essentially arguing the case that per capita emissions quotas are unrealistic - to which Karoly responds that they are more likely an end goal of a longer term process than an immediate imposition. The presenter argues that without a global agreement Australia shouldn't bother doing anything, to which Karoly explains why it's important for Australia (we're likely to the worst affected of the developed countries, and IIRC it shows leadership regarding what can be done).

> My debate with david Karoly is on youtube.

I'm not seeing a debate. It's not structured as one - it's styled as a journalistic interview, and even then the presenter is not demonstrating any challenge to the science and certainly not landing any blows.

In the last couple of minutes the presenter claims "there does seem to be a growing body of scientists who don't agree with the consensus" and brings up the infamous Manhattan Declaration and Oregon Petitions - which is an instant credibility flush. Karoly essentially responds by pointing out the credibility problems in contrast to more credible surveys - and the difference between noise on blogs and actual science.

Overall Karoly puts his case quite clearly with care and precision - for those who have ears to hear.

The end of the clip says there's another part - haven't had time to watch that yet.

Yes it was an interview.I could not really describe it as a Structured debate,though we did debate the issue.I did not intend to mislead in that regard.The same goes for Ove H-G,that is,it was more of an interview than a set debate.But again we did debate the issue.I should have made that more clear.

I'm brave and I'm strong. I did both of them.

Karoly is very good. He's also very polite and he suffers from typical scientific restraint and qualificationese. He just wasn't prepared to say, flat out, that Lindzen's work was unsatisfactory, because he hadn't personally done the work that contradicted Lindzen.

Not a single punch landed.

> My debate with david Karoly is on youtube.

So...when you say "debate" you mean "interview"? That's not how I would use the word "debate".

Anyway, quick notes on part 2 (which is "episode 2 part 3").

Interviewer: skeptics say there's no robust attribution for any observed warming to anthropogenic causes.

Karoly: hundreds of papers that show human causes are responsible for most of the warming over the last 50 and 100 years; skeptics and deniers have not published any that show any other causes.

Interviewers: skeptics say that attribution relies on a default [i.e. that GHG by default must be the cause] because we don't understand the system completely and can't pin down any other cause.

Karoly: No, no! You have misunderstood what I said. The papers have looked at a range of causes - not by default, but by analysis - that the contribution due to GHG is responsible for most of the warming compared to the contribution due to the other causes.

Interviewer: why does the IPCC say "very likely" and "most of the warming".

Karoly: already quite strong statement...

Interviewer: critics say there's no central piece of evidence to demonstrate it.

Karoly: there is absolutely. E.g. patterns of warming such as more warming in winter than in summer, at high vs low latitudes, at night vs day, in lower atmosphere or upper atmosphere.

Interviewer: urban heat island effect?

Karoly: doesn't warm oceans - e.g. polar regions without major cities. Not due to several other causes [often raised by "skeptics"] - including solar radiation, cosmic rays, land use.

[And best line of interview:] "They might be due to invisible Martians with heaters, that we can't see, but it's unlikely."

Interviewer: tropospheric hotspot has not been observed.

Karoly: Not true.

Interviewer: it was predicted but not observed directly.

Karoly: It has been. Cites various studies plus assessments by various national science bodies.

Interviewer: contentions about climate sensitivity. Stefan-Boltzmann constant tends to suggest warming of one degree [Celsius?] Cites Idso & Kininmonth. IPCC says 1.5-4.5 degrees based on models; skeptics say no clear evidence it could be as high as 4.5.

Karoly: change purely due to CO2 is about 1 degree, but many other factors - e.g. changes in water vapour, clouds, ice. Best estimate of warming is 3 degrees. Range is about 2 - 4.5. Convincing observational evidence that there is negligible likelihood of only 0.5 or 1 degree.

Interviewer: Lindzen, observed results from satellite data, warming in tropics restricted to only 0.5 degrees. If correct, not much to worry about?

Karoly: firstly Lindzen selected an uncorrected satellite data set - the correction changes the results significantly.

> I have debated both David Karoly and Ove Heogh-Guldberg,and I atleast held my own.

Not on the evidence I have seen. You merely presented known-to-be-bogus denialist talking points and had each one shot down in turn.

If that's "holding your own", then I'm sure you can similarly "hold your own" with Jeff Harvey - but it won't bolster the case for the argument you are makin

Just watched the interview.

David Karoly has the patience of a f'ing saint.

Warren writes:

>>*I have debated both David Karoly and Ove Heogh-Guldberg,and I atleast held my own*

>so what you claimed was a debate was in fact your interview with Karoly?

>*Yes it was an interview.I could not really describe it as a Structured debate*

So you "*atleast held [your] own*" in what manner?

>*though we did debate the issue.*

Oh really can you link me to that then, as that is what I was asking for.

>*I did not intend to mislead in that regard.*

In which regard, that you did debate him, that you held your own debating him? Or that you didn't debate him but you did debate the issue? Or all of the above?

>*The same goes for Ove H-G,that is,it was more of an interview than a set debate.But again we did debate the issue.*

So you didn't debate Ove but you did debate the issue? How did you managed that?

>*I should have made that more clear.*

No time like the present to start to set that straight Tim.

I just [read Loth](http://scienceblogs.com/deltoid/2010/08/the_co2_is_plant_food_crock.php…). FTW!

AHA, so what exactly are you 'Warren'? A humble science teacher or have you finally been 'outed'? Is this what gives you kicks?

As for convincing a scientific audience, perchance please tell me how many scientists you persoanlly know who are pushing the line that 'more C02 is good for plant life' but without the caveats I have repeatedly discussed and which you have repeatedly ignored. My argument is much more diverse than that. I see the game that you are playing, and it does not make the cut. My argument is and has always been that the effects of enhanced C02 on ecological communities, systems, and biomes is impossible to predict given the unknowns and could be seriously negative in many cases. Your argument stops at 'C02 is good for plant life'. How far are you willing to take this argument beyond the microcosm stusies that you rely on? It seems that every time I enter into the aspect of complexity, you shy away and retreat to your little cave, citing studies showing that many plants grow better under elevated C02. I have never doubted that most species will grow larger; this is elementary science. What I do dispute is (1) that these effects will be linear, and thus exert little or no effects (or even beneficial effects) on larger scale systems, and (2) that the ratios or important primary and secondary metabolites in plants will also increase in proportion. I also dispute the argument that more C02 = bigger plants = good for nature argument. We have no idea how increases in C02 - especially the rate at which this gas is increasing - will affect systemic reslience and stability, or if there will be many winners and losers owing to intra- and interspecific related effects occurring at local scales. On this argument I have 99.9% of the scientific community behind me. The main bulk of contrarians on this point are (1) retired right wing economists, (2) supposed science teachers who are in fact pundits, and (3) other assorted non-scientists who are pushing political agendas. Please find me any scientific article published in a rigid journal which claims that increasing C02 in the atmopshere will beneift plant and animal life and make ecosystems stronger and more resilient. Just one.

Certainly your so-called 'debate' with Karoly did not scare me at all. And you strike me as being intellectually dishonest when you claim to want a debate with me on 'catastrophic climate change'. Where the hell did that come from? Since when have I discussed 'catastrophic climate change' in this thread? My arguments have consistenly been based on the vast number of unknown effects that increased C02 will have on the functioning of complex adaptive systems. Your arguments have been based on microcosm studies usually excluding a myriad of other biotic and abiotic processes that have measured plant growth in ambient or elevated C02. At the same time, you have refused to explain how this will affect the assembly and functioning of ecosystems. A good analogy is that ecological complexity goes on a log scale from 1 (most simple at the level of individuals) to 100 (most complex at the level of the biosphere). Thus far, studies have produced mixed results for increases in C02 on community-level interactions and on plant stoichimetry, with more positive results for plant biomass. However, on the 1-100 scale of complexity, we have only gotten about to points 2 or 3 in understanding the effects of increased C02. In other words, no further than microcosms or perhaps small-scale mesocosms. On this basis, speaking as an experienced scientist, I am very cautious and concerned about the effects of increases in C02 at larger scales - between 3 and 100. Try and find an ecologist who would disagree with this. Even most of those writing the closed studies, many of whom are not ecologists, would have to admit that the jury is out on larger scale effects. In other words, it is a crap shoot. A roll of the dice on complex adaptive systems that sustain us in a myriad of ways.

In his recent appearance on a TV debate in Australia, the late Stephen Schneider said to be wary of anyone who exerts complete confidence in any scientific process associated with climate change. By nature, scientists work on probabilities, and not absolutes. I believe that if there is a 20% chance that pumping more and more greenhouse gases into the atmosphere will unravel many important food webs, and precipitate collapsing ecosystems, then we should do everthing in our power to keep C02 levels below 450ppm. We do not understand enough about the factors maintaining the stability and effective functioning of ecosystems to be able to confidently assert that our tinkering with it in so many ways - C02 increases included - will not have serious effects. People like 'Warren' or whoever he is do not hold such reservations. They are not scientists in the classical definition of the term, but contrarians, who believe that without 100% proof of a problem or process that there is no problem and that we should therefore continue on the current path.

I therefore will not debate 'Warren' here on the criteria he has set. It would have to be on the basis of unknowns and the functioning of complex systems. I know the trap that he intends to set for me and I will not take the bait. He will claim that C02 is good for plants citing his limited studies and then say that I cannot prove that it is not only bad for plants but for the systems in which they are embedded, because we have no or very little data from them. Sorry 'Warren', but I know the tricks of the contrarian trade. For the time being I will debate you on this thread and if you want to be taken seriously I expect you to answer ALL of the points I raise, and not those of your own choosing.

Jeff Harvey:Well this has been all one great big tease.First you say you would 'love' to debate me,and now you are running away because you dont think you can win.What happened to that PHD bravado of yours? You said a debate with me would be a 'slum dunk' and 'utter annihalation'.Now you want to debate about 'unknowns and the functioning of complex systems'.It does not matter Jeff,even if we came up with a propostion which was to your liking,you would never agree to a debate,so lets drop the idea.There is also very little value in continuing this discussion as the only thing you come up with time and time again is "the unknowns".Should Alexander Fleming have not done his work to discover Penecillin because of the 'unknowns'?Should Watson and Crick not investigated DNA because of the 'unknowns'?I have presented data;you have presented doubts.And that is why it is impossible to 'answer all of the points'as you say.They are based on doubt,and therefore they cant be quantified.
To your last post,you asked for 1 scientist I know personally? I know Bob Carter personally,though; not well.

Warren, or whoever the hell you are,

I would certainly debate you on the terms I have argued throughout this thread. But since you never reply to the substantive points I make in my posts (is this because you do not understand basic ecology or know that you are out of your depth?) and then yopu claim to want to debate me on 'catastrophic climate change' or else 'C02 is good for plants', why not on the proposition, 'The effects of increased C02 on large scale communities and ecosystems is largely unknown and may be highly deleterious'? My aim is, and always was, to highlight the potential consequences of gaps in our knowledge as to the effects of C02 on individuals, communities and ecosystems. I do realize that in doing this, you will be well out of your intellectual depth, and thus you will stick close to your 'most plants grow better under elevated C02 regimes' whilst ignoring the broader implications.

So sure, if you wanted to come here and debate complex adaptive systems with me, go ahead, look an idiot, especially when you will peel off selected results from microcosm stu'dies, I will do the same but with quite different results, then I will say, 'let us scale up the processes and look at ecological interaction networks, food webs and ultimately ecosystems. I will go on to argue that, because the effects of increased C02 will be association (= species) specific, there will be winners and losers: the losers will not necessarily lose because of increased C02, but in competition for other resources, namely light, other nutrients, and through allelopathy. And the effects of these on herbivores and further up the food chain will also be highly unpredictable, meaning that, as I said in my last post, and which you habitually ignore, we are gambling that all will be OK. Its a crap shoot. You will then say, 'Hey, but Jeff, all of this is heresay, unknowns and I am only talking about plant growth in a quantitative sense' (again, because you do not understand the bigger picture and are pushing what I consider to be a political point).

Lotharsson summed it up perfectly when he said:

*Furthermore I and others have pointed out that - even based on known data - your definition of "beneficial" is very one-eyed and limited in scope, but you pretend that it is the only definition that matters*.

Exactly. Your definition is but one component of a multi-dimensional process. Most plants grow bigger under elevated C02. Therefore bigger is better. Nature prospers. Man prospers. We all live happily ever after. And so on and so on. But as I said, it is not this simple. Not nearly so one-dimensional. I have said this over and over again, and you continaully return to the starting point. What is there to debate? Sure you will plug some studies. But they are not the bottom line when we expand the spatial and temporal scales. I am certainly willing to debate the potential consequences of bigger (though not necessarily more nutritious) plants, as well as on intra- and inter-specific differences in plant responses to increased C02 and the potential consequences for ecosystem functioning. Can you do this? I do not think so. Your world is one-dimensional. Any audience would see that, even it was made up of factory workers.

Bob Carter? Please do not make me laugh. What research has he done on plant ecophysiology and community ecology?

Jeff Harvey:OK,so you are now wanting to debate again?Are you sure?Dont change your mind now!So our subject is, "The effect of increased CO2 on large scale communities and ecosystems is largely unknown and could be highly deleterious".If that is the subject then,yes I will debate you on it.If you are comfortable with that propositition then I am also.Do you also agree to the friendly wager on the outcome of the debate?

Jeff Harvey:Bob Carter??You asked for 1 scientist I know personally....,I answer you,and so now you change the goal posts again and say he has not done any research.That was not what you asked for!Make your mind up man!

What on earth have we done to deserve this latest version of troll?

Seems to be some kind of You Tube Tom Fuller.

Warren (again, if this is who you are),

Debate me first on the specifics of what I write on here. I wasted my time once before debating a contrarian here in Holland on the topic of 'Is the current loss of biodiversity a concern' in front of a large audience. Turns out that my opponent, although a scientist, didn't know a damned thing about the topic and complied for the most part that there was 'too much dogma'in ecology. He was also an adviser of an anti-environmental web site in the Unbited States.

As for Bob Carter, I never said he wasn't a scientist but that he has as far as I can tell no expertise in the field of plant physiology and ecology. I know of Carter as one of NZs biggest climate change sceptics, and that he attends right wing think tank 'conferences' where climate change is downplayed. But if this is the one name that you can dredge up in relevant fields, then this shows how thin the 'other side' is in terms of scientific expertise.

Unfortunately, Michael's post (469) sums up my feelings as well.

Forget the whole thing Jeff.It is a waste of time even discussing it,you will never agree.Funny how you were so gung-ho before.

> Forget the whole thing Jeff.It is a waste of time even discussing it,you will never agree.

Why is it wrong to never agree that black is, actually, white?

Jeff is willing to talk with you f2f on the effects of CO2 increases in the earth's atmosphere over the BAU proposals for the coming 90 years.

But you don't want to do that, since you'd be toast.

Funny how you were so gung-ho before.

Bob Carter showed his level of incompetence with his involvement in the [Mclean debacle](http://scienceblogs.com/deltoid/2010/04/john_mclean_hides_the_declines…).

Jeff, Not knowing Brisbane TV my assumption is that Warren (Tim O'Brien Wells) is not on mainstream TV. There are only a handful of O'Brien's uploads on youtube. Form the production values its a homemade piece which might at best appear on a "community station", one of those with very low ratings, and if its like my state I couldn't watch if if I wanted to due to it very poor reception.

I.e. wouldn't rate Warren as a pundit.

Oh, I don't think anyone's over-rating Warren at this point, J.

;)

I thought that warren (nee Tim) was going to travel to see Jeff?

warren, will you converse with Jeff on the subject you've insisted you know better than him even though it is his area of expertise, the biological web of the environment and its reaction to an increase in CO2 in the global atmosphere?

Changing climate would be included only in so far as it pertains to the biological response of food crops.

Or have you gone off the idea, like another Tim did about his challenge to drink salt water laced with CO2 to "neutralise" it..?