The IPCC Forth Assessment Synthesis Report has been released. The Summary for Policy Makers is in Microsft Word format, so I've made a PDF version for easier reading.
A few extracts:
Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level (Figure SPM.1).
Average Northern Hemisphere temperatures during the second half of the 20th century were very likely higher than during any other 50-year period in the last 500 years and likely the highest in at least the past 1300 years.
Most of the observed increase in globally-averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic GHG concentrations.7 It is likely there has been significant anthropogenic warming over the past 50 years averaged over each continent (except Antarctica) (Figure SPM.4).
Partial loss of ice sheets on polar land could imply metres of sea level rise, major changes in coastlines and inundation of low-lying areas, with greatest effects in river deltas and low-lying islands. Such changes are projected to occur over millennial time scales, but more rapid sea level rise on century time scales cannot be excluded. {3.4}
Climate change is likely to lead to some irreversible impacts. There is medium confidence that approximately 20-30% of species assessed so far are likely to be at increased risk of extinction if increases in global average warming exceed 1.5-2.5oC (relative to 1980-1999). As global average temperature increase exceeds about 3.5oC, model projections suggest significant extinctions (40-70% of species assessed) around the globe. {3.4}
There is high agreement and much evidence that all stabilisation levels assessed can be achieved by deployment of a portfolio of technologies that are either currently available or expected to be commercialised in coming decades, assuming appropriate and effective incentives are in place for their development, acquisition, deployment and diffusion and addressing related barriers. {5.5}
In 2050, global average macro-economic costs for mitigation towards stabilisation between 710 and 445ppm CO2-eq are between a 1% gain and 5.5% decrease of global GDP (Table SPM.7). This corresponds to slowing average annual global GDP growth by less than 0.12 percentage points. {5.6}
Update: Elisabeth Rosenthal in the NY Times writes:
Even though the synthesis report is more alarming than its predecessors, some researchers believe that it still understates the trajectory of global warming and its impact. The I.P.C.C.'s scientific process, which takes five years of study and writing from start to finish, cannot take into account the very latest data on climate change or economic trends, which show larger than predicted development and energy use in China.
"The world is already at or above the worst case scenarios in terms of emissions," said Gernot Klepper, of the Kiel Institute for World Economy in Kiel, Germany. "In terms of emissions, we are moving past the most pessimistic estimates of the I.P.C.C., and by some estimates we are above that red line."
Nice!
Just waiting for the reaction of "climate sceptics", but more importantly, the reaction of policymakers...
Hi all
Why is Antartica not warming?
Theory says it should be more than the tropics I thought.
Regards
Peter Bickle
Peter B,
My understandgin is that Antartica is in fact experiencing some effects of warming, but due to winds and currents of the region it is largely locked off from most of it all. Both models and observatiosn say.show as much.
Models and observations suggest that it is the Artic which is going to bear the brunt of climate change.
Hi all
Models used to suggest that Antartica should bear the brunt of the warming. Perhaps the models are wrong then? This leads to how reliable present models are?
Regards
Peter Bickle
models also used to suggest that the earth was flat. perhaps the round earth models aren't reliable either. grow a brain please.
"Models used to suggest that Antartica should bear the brunt of the warming."
Which models were these exactly?
Perhaps Peter Bickle is wrong then. Wouldn't be the first time.
"Models used to suggest that Antartica should bear the brunt of the warming."
Which models were these exactly?"
Well, I think it may have been Heidi Klum.
Peter says:
Bullshit. Prove your point by quoting such a model.
Aren't you ashamed to be caught out lying like this?
Yes, the earlier models showed polar amplification at the South pole as well. However, these older models (from pre 1980 I think) did not attempt to model the deep ocean. The deep ocean makes a huge difference in the southern hemisphere. Additionally, changes in the Southern Annular Mode believed to be brought about by ozone depletion have been recently observed. These changes also work to keep Antarctica cool--for now.
So, this is the typical denialst garbage. A little bit of truth taken out of context. Either they know the story about models--in which case they are liars, or they don't know anything at all.
Hi all
Why use the name denialist?
I am a sceptic. I have never said climate changes, I am just sceptical of the cause and the amount of the forcings etc. Being a scientist myself I have asked questions all of my life, but if I go against the consensus I am called a denialist. There is a massive difference between these terms.
Also, this is a valid question on why the Antartic is cooling while the artic is not?
Regards
Peter Bickle
Peter B,
looking at page 8 of 24 of the summary Antartica is projected to increase it's mean average surface temp by 2-3 degrees C over the 1980-99 average, depending on the area, by the last decade of the 21st Century.
This is alot less than other land areas between the poles, largely because of polar ocean and wind currents block warm temperate currents from interacting with it; and because there is a tremendous amount of ice which won't to turn dark water when lightly melted. In short the exact oposite conditions exist in the Artic whichexpect to receive the most climate change.
Thanks to Tim Lambert for making available the fatuous AR4 latest, which states that "Warming reduces terrestrial and ocean uptake of atmospheric CO2, increasing [sic] the fraction of anthropogenic emissions remaining in the atmosphere". That is of course a blatant lie. Even the CSIRO's Canadell and Raupach, both Nobel winners as co-authors of this farago of nonsense, admit (in their NPAS offerings, especially #2 in October 2007) that those uptakes have actually been growing FASTER than atmospheric CO2 since 1990 (Table 1). When the IPCC cannot even report what its own favourite sons actually say, the rest is demonstrably garbage (as one would expect from an organisation that has no knowledge of - it certainly cannot bear to mention - photosynthesis).
"Why use the name denialist?"
A denialist includes someone who uses dishonest rhetorical tricks such as quotation out of context, strawman arguments, making mountains out of mole hills and non-sequiturs. Peter Bickle uses these tricks so that makes him a denialist.
One thing about IPCC, at least it keeps Tim C and Peter B occupied and out of their kids' hair.
"There is a massive difference between these terms. Also, this is a valid question on why the Antartic is cooling while the artic is not?"
I believe Nic Stern had the answer for that. In his famous economic report he argued that climate chaange would worsen gender inequality. I would therefore argue that the reason the sth pole isn't warming like the nth is al to do with gender differences. Why? Who knows and who cares. You can ascrivbe anything to AGW these days.
Jc: "Who knows and who cares."
That'd be right. Jc arguing about something he knows nothing about.
Thanks for the link, Tim.
The IPCC report is now also in pdf format, but the graphics in your version are of a much better quality.
Plus the IPCC server is getting hammered right now.
Tim Curtin #12,
From the paper you cite:
The increasing positive numbers for sinks in fig.1 aren't for increases in absorption of CO2 by sinks, but calculated values for the net contribution of lowering absorption efficiency of sinks to the atmospheric fraction of CO2.
It is not nice to call people liars if one does not understand what they are saying.
Given that a quick reading of Caradell,et al. is sufficient to verify that their paper actually makes a claim completely at odds to what you say they admit to, however, gives one ample evidence to conclude that not only are you a liar, but a very stupid one at that.
Tim, seems your pdf version is both smaller AND has better looking graphs than IPCC:s own pdf! Thanks. :)
Luminous Beauty (aka Ugly Mind):
This is the IPCC as provided by Tim Lambert: "Warming reduces terrestrial and ocean uptake of atmospheric CO2, increasing the fraction of anthropogenic emissions remaining in the atmosphere". That clearly states that warming such as began about 1980 reduces the ABSOLUTE uptakes. What has actually happened as Canadell et al show is that there may have been some small (and insignificant statistically) decrease in the PROPORTION of total emissions taken up (in their Table 1, from 56% in 1970-1999 to 54% in 2000-2006). The declining proportion if any does not result from an absolute decrease in "efficiency", as uptakes actually INCREASED from average annual 4 GtC in 1970-99, to 5 GtC p.a. in 2000-2006. That shows there has been an increased quantum of uptakes, albeit not as fast, yet, as the cited growth in emissions.
As for Canadell et al, no fewer than 6 of these 10 co-authors were co-authors of IPCC WG1 ch.7, But although there they were agreed that the oceanic sink is larger than the terrestrial, in FAQ7.1 and Table 7.1 (by -2.2:-0.9), in the same month that WG1 appeared they published in PNAS showing the land sink larger than the oceanic since 1990 if not before (by -2.8:-2.2). With science and measurement like that, we might do better to rely on President Mugabe's witch doctor who recently persuaded him and his cabinet that she could produce refined diesel from granite rocks.
So, the IPCC invites experts to contribute to their effort.
Which somehow is a slam on their reputation?
Puerile as ever, dhogaza misses the points (1) that the IPCC structure implies that it is an independent Panel reporting on independent science, but when most of the Panel's authors are also the authors it relies on, there is an inherent conflict of interest, and (2) that when Canadell and the other 5 say one thing in the IPCC's AR4 WG1 and the opposite in Canadell et al, they are as reliable as Pres. Mugabe's spirit medium. At least Gore used Mann to verify Mann: Canadell et al 2007 contradict IPCC's WG1's Table 7.1.
Hi all
Wait for the flames to burn you down Tim, you are a heretic, blah, blah, blah. This is a classic case of turkeys voting against Xmas and is a reason I am a sceptic, not a denier. My scientifically trained brain makes me a sceptic you see. I question.
Regards
Peter Bickle
Honest skeptics are actually interested in the answers.
Poor TimC. With no facts to marshal, he must resort to things like 'fatuous' to dismiss the IPCC report.
Awwwww. My heart would bleed for you TimC, but you'd never see it, as us tree-huggers have turned our hearts away from the obfuscators.
Best,
D
What has happened to Tim Curtin, he used to make at least some sense, but this latest jag that he is on surpasses the peace of God for idiocy.
Tim Curtin'
It does not clearly state that the uptake of CO2 is absolutely reduced, but implies that the rate of uptake relative to increasing anthropogenic emissions of CO2 is reduced, which is exactly the conclusion of Canadell, et al. To interpret this statement as you do is a strawman argument. And a lie.
Gore stated clearly and unambiguously that Thompson's study of high altitude tropical glacial cores supported MBH99. The ridiculous argument that he used Mann to support Mann is a conclusion that could only come from people who only acquire information from looking at pretty pictures on a board.
Another strong piece of evidence that you are stupid.
Dear all
Your opinions please on this link to the antidote to the IPCC, which also serves to warn of the risks inherent in reducing CO2 emissions precipitately:
http://www.johnsongas.com/industrial/CO2Gen.asp
(Hat tip to Tim Blair)
You're a very funny fella Tim.
TimC wants us all to live on a world like Silent Running to keep his ignorance fetish going.
Best,
D
So, in a greenhouse, wtih attentkion paid to ensure that plants get optimum temperatures, optimum levels of all nutrients, optimum levels of water, where no nutrient is limiting for productivity - CO2 is advertised to increase productivity.
Tim Curtin - exactly how is this information relevant to the outside world in which the relevant plants are growing?
And how exactly does that one possible - but minor at best - 'benefit' of CO2 stack up the the costs of AGW and ocean acidification?
i.e. NET ocean-to-atmosphere flux and NET land-to-atmosphere flux, the latter with a note saying "Balance of emissions due to land use change and a residual land sink. These two terms cannot be separated based on current observations."
and as well as these sinks there was also a Land Use Change source (1.5) which when added to the gross land sink in PNAS should give the NET land-to-atmosphere flux in AR4 WG1 Table 7.1 which indeed it does within the error range claimed by AR4 WG1 Table 7.1 (-1.3 compared with -0.9+/-0.6).
Poor Dr.(deserved) Curtin, succumbing to blindness in his old age. Perhaps he could offer his reading services to President Mugabe.
Nice try, Crass (#32), but whereas Ugly Mind (#27) can't grasp basic English, you are numerically challenged. If we add the "land use change flux" which Canadell et al et al state in Table 7.1 of AR4 WG1 ch 7 was "n.a." but which Canadell et al in PNAS Oct 2007 Table 1 state was 1.5 GtC(annual average 2000-2006), we then have total emissions of 8.7 GtC in AR4 for 2000-2005, and with the oceanic uptake in both at 2.2, the gross earthly uptake then has to be 2.4 (given the net 4.1 increase in atmos CO2 in both tables) for a total gross uptake of 4.6. That is 52.87% of the total emissions including land use flux of 8.7 in 2000-2005. The equivalent figure in PNAS for 2000-2006 is 54.95% (naturally reported with their usual honesty by Canadell et el in PNAS as only 54%, but then they share their honesty with you, which is why it shows diminishing returns). So we have the Summary for Policy Makers of AR4 in November 2007 stating on the basis of Canadell et al et al that absolute oceanic and land uptakes "decline" with warming, when if Ugly Mind is to be believed they really meant "relative to the growth in emissions", but Canadell et al in PNAS unblushingly show that the relative proportion of uptakes was higher at 54.95% in 2000-2006 than in 2000-2005 (when it was 52.87%). The 6 Canadell + IPCC Clones in PNAS evidently could not be bothered to communicate this change to the authors of the AR4 Synthesis Report, thereby including themselves in the whole, not merely charade, but fraud of the whole IPCC enterprise. I know something about IPOs on the ASX, and that kind of unremarked change of even only just over 2% (it amounts to 0.4 GtC pa. from 2000, or 2 GtC in total over just 5 years, big bikkies if they were dollars, and more so in CO2) is unacceptable, given the huge policy issues at stake relative to those of a mere share flotation. But then you and Ugly Mind will no doubt concur with the IPCC Mafia that a change in uptakes from 53% to 55% is really both an absolute and relative decline. G'day.
Why would anyone waste their time even opening this report which is the *work of politicians and their bureaucrats*. Normally you smart(!), intelligent(!), not to say, downright cynical people wouldn't take the word of a mealy-mouthed pol if he told you the time. Suddenly, you're all as gullible (now where have I heard that word recently?) as the mugs, ooops, sorry, customers who used to buy cars from me.
The stupid. It burns ...
Or perhaps you're just lying?
It's David Duff. Read his blog. He's just trying to annoy people.
Mr. Ghozada, where I come from it is considered to be, at the very least, impolite to accuse some one of lying. Perhaps, on reflection, you might care to rephrase your comment.
And whilst you're at it, you might care to explain your mysterious and cryptic comment "The stupid. It burns ..."
On the interwebs, it is common to call someone a liar when they are.
As for the stupid, it burns, it is a parody of Gollum from Lord of the Rings, I think, transferred across to Creationists. I first saw it applied to Creationists posting at "uncommon Descent", an ID website where all dissent, including posts much nicer than yours, is banned.
"On the interwebs, it is common to call someone a liar when they are."
It might be on the sort of, er, 'interwebs' that you habituate, Mr. Guthrie, but not from where I come. There, it is considered rude and is met with a sort of pitying smile because it reveals so much about the person who writes it.
More to the point, is anyone going to demonstrate to me that the IPCC is *not* a political and bureaucratic gloss applied at the United Nations to a preceding scientific report upon which other scientists have cast doubts? If that is the case, then why on earth would any one use it unless they had run out of toilet paper?
What's that phrase ... "ignore the troll"? Something along those lines?
Used-car dealer: "this report is the work of politicians and their bureaucrats"
Would you buy a used assertion from this man?
*"is anyone going to demonstrate to me that the IPCC is not a political and bureaucratic gloss applied at the United Nations"*
After a good night's sleep I see that the only non-replies to my challenge are from Mr. Zhadoga and Mr. O'Neill, so I'll take it as a 'no, shall I?
At least our host knows better than to dispute my point because in the post immediately below this he points up some of the political haggling that has occurred. May I look forward to an apology from Mr. Hazgado and Mr. Guthrie for calling me a liar? Take that as another 'no', shall I?
depp=true
notiz=[Please do not feed the troll]
THe liar bit, since you are too stupid to see it yourself, is where you assert that the report is the work politicians and bureacrats. Now, as allegedly an ex used car salesman, you are used to making baseless assertions (Only one owner, runs like a dream, etc) but on the internet you are held to a higher standard of proof than in used car dealerships. So, where is your evidence that politicians and bureacrats wrote the report?
For example, acknowledged scientists and experts in their fields write the various reports that the summary report summarises. Perhaps you can dig out other information?
Oh, and the stupid bit is in ignoring what this report says merely on the basis that it was supposedly written by politicians and bureacrats.
And if there is still anyone around, other than some of the commenters here, who retain a touching faith in UN scientific reports, let me point them in the direction of a story in today's prints telling us that the UN has had to revise its AIDs forecasts downwards and admit, finally, that the whole scare story of a global epidemic was overblown. The number living with AIDs is *down* by 7 million, and the estimate for new infections is *down* by 40%. AIDs in India is *down* from 6 million to 3 million.
So, hey-ho, the 'deniers' were right after all!
depp=true
notiz=[Please do not feed the troll]
Mr. Lambert, was it you, or others, who scrambled my perfectly polite comments above whilst allowing others to call me a liar for repeating an assertion that is supported by your own post? If it was you, am I to take it that I am now banned?
Tim Curtin said: "With science and measurement like that, we might do better to rely on President Mugabe's witch doctor who recently persuaded him and his cabinet that she could produce refined diesel from granite rocks."
Yes, indeed. In my eyes, comparisons between scientists and corrupt heads of state always increase the weight of the argument.
What a devastating argument.
David Duff:
It's really hard to say which of your comments make less sense -- the scrambled ones or the ones that are left untouched.
Well, JB, you'll never know. As I haven't had the courtesy of a reply from Mr. Lambert I must assume that it was he who censored my words. This site, and Real Climate, which also refuses to publish dissent, go well together and stand in direct contrast with Climate Audit (and my own poor site) which positively encourages debate and argument. Here, it's just 'liar, liar' and bring on the censor. Ask yourselves, is it any wonder that increasing numbers of people like myself who were neutral to begin with on the subject of global warming have been driven into the doubters camp by the witless, humourless, clumping fist mentality of the 'warmers'?
Look in the mirror, Gentlemen, your scowling, furious faces are not a pretty sight!
Yet another lie.
Why do you bother when anyone who cares can go read current threads at Real Climate and see plenty of dissenting comments?
I don't get it.
"Real Climate ... also refuses to publish dissent"
Real climate allows dissent, but it has to be relevant to the science.
When it comes to science, not all dissent was created equal.
Saying the "earth is flat" is not scientific dissent. It is just stupid.
Duffman,
"Look in the mirror, Gentlemen, your scowling, furious faces are not a pretty sight!"
Project much?
Me: *"Real Climate, which also refuses to publish dissent"*
Them: *"Yet another lie."*
And another them: *"Real climate allows dissent, but it has to be relevant to the science. When it comes to science, not all dissent was created equal."*
Perhaps you should meet and get your story straight! A debate is a debate, and censorship is the same old last resort of the weakling it always has been.
Mr. Lambert should hang his head in shame at giving every appearance of being the first gutless Aussie I have ever come across.
depp=true
notiz=[Please do not feed the troll]
Duffman,
Really! RealClimate allows dissent, but draws the line at quacking fools. No kidding!
Tim Lambert tolerates quacking fools. He is allowing you to comment here despite being driven to disemvowel you a couple of times for, dare I say, irrelevance.
C'mon, say something relevant.
Poor, poor, poor Dr.(deserved) Curtin. Even when he is shown his enormous error:
i.e. that the -0.9 and -2.8 refer to two different things, he can only respond with a red herring. So, so sad. To think the discoverer of Curtin's law of conservation of atmospheric mass, the equivalence of exponentials and polynomials and Curtin's law of eternally increasing carbon uptake can come to such a sad end.
Some think the drapes covering their windows know more math than Curtin, but we all know that's not true, don't we?
Crass: you are too clever by half.
I stand by what I said on 6th August (#118 in Cherry picking stations)
So the fact remains that the stock of CO2 (x) plus net emissions (y) minus net uptakes (z) will definitely fall as we move to 80% reduction of emissions as of 2000, where the latter fall by say 5% pa to reach the 80% target by around 2050, and z keeps it up at today's rate while there is still some CO2 around.
Using the Candell et al numbers, with total sources of 9.1 GtC (annual average 2000-06), and 55% of that taken up by the globe (land and ocean)for a net average annual increase in atmospheric CO2 of 4.1 GtC, if the fossil fuel emissions are reduced as widely proposed to 20% of 7.1 GtC, then they fall to 1.52 GtC p.a. which is well below the Canadell uptake of 5 GtC. That leads cet.par. to a rapid reduction in atmospheric CO2 of possibly as much 1.77 ppm p.a. Your higher maths than mine will tell you what that means for crop yields by say 2057. Alternatively how are we better off if the uptakes decrease pari passu? As a famed agronomist you must know the exact relation between atmospheric CO2 and crop yields, especially given the much stronger correlation between these than there is between CO2 and temperature anomalies (R2=0 or close to).
TimC, how many times does it take this to get through your head: THERE IS NOT A LINEAR CORRELATION BETWEEN ATMOSPHERIC CO2 CONCENTRATION AND PRIMARY PLANT PRODUCTION OR CROP YIELDS. Carbon is often not a limiting nutrient for plants, nitrogen is. And the C:N balance is shifting under enhanced atmospheric carbon levels. Moreover, these effects vary in C3 and C4 plants. Finally, as nitrogen is shunted from plant tissues, insect herbivores will be forced to adjust their feeding rates and increase their total plant biomass consumption because nitrogen is a highly limiting resource for insect growth and development. Thus, insect pest outbreaks are likely to increase with a concomitant increase in atmospheric CO2.
You just haven't thought any of this through, you just hit the reader with one simplistic misinterpretation after another of both the underlying science of global change and the likely consequences of it. For the final time: the relationship between cause and effect in ecological systems is profoundly NON-LINEAR. I read the same kind of jibberish as yours from denialists all of the time: they argue endlessly that changing one component in complex adaptive systems leads to predictable effects. But they categorically DO NOT!!! The only general rules emerge over sufficiently large spatial and temporal scales. Predicting individual plant and consumer responses to enhanced atmospheric CO2 regimes is just not possible.
Hi Jef:
You tend to have a linear uni-directional frame of mind. Moreover you are quite wrong: the adjusted R2 between the FAO index of food production and the Mauna Loa measure of atmos. CO2 from 1980 to 2003 is .99.
My question is, what if we reduce CO2 from 381 ppmv as now to 300 ppmv or less by 2050? What is your best estimate of crop yields then?
Tim Curtin is either insane or playing us all for fools.
He can't really be this dense, can he?
Tim, please, put my mind at ease - you're just trolling us, right?
"I stand by what I said on 6th August (#118 in Cherry picking stations)"
i.e. #118:
To which was commented #120:
and #121:
The great Dr.(deserved) Curtin, one of the great mathematicians of our time.
Tim Curtin,
The notion that net CO2 uptakes will remain constant as CO2 concentration declines is a seriously flawed notion. If all CO2 sources from anthropogenic causes were immediately curtailed the system would continue to seek equilibrium at higher temperatures than we now experience, driving down the uptake rate until it approximately stabilizes at net zero. It is only because there is concentration of CO2 in the atmosphere greater than uptake/emission equilibrium that there is net positive CO2 uptake in the first place. It's first year physical chemistry.
It's a feedback.
Agricultural expansion represents a net loss in both albedo and CO2 sequestration feedbacks in reference to lowering surface temperature and CO2 concentrations. Ag production may well have benefited from warmer temperatures in the twentieth century, although there are more compelling proximate causes, e.g., increased acreage under cultivation, increased per acreage yield due to hybrid seed stocks, artificial fertilization, etc. That is no reason to believe they will continue to do so at even higher temperatures, nor that the proximate causes I've mentioned won't prove to have self-limiting features. Rice production in semi-tropical climates has already been shown to be negatively impacted by rising night time temperatures, even though they are swamped out of gross production figures by the proximate causes I've mentioned and temporarily increased rainfall.
It is a bit of a puzzle to me why economics based thinkers (and I use that term in its most generous sense) have such a difficult time distinguishing causality and correlation.
Is it because working economic theory (current business practice) has very little physical causal basis and is highly conditional on the vagarious decisions of human beings manipulated and deluded by semantic and semiotic appeals to their subconscious desires? A very small subset of human decision making process that nonetheless drives a very powerful engine of wealth production.
Like, if you can fool enough people enough of the time, you can make a tidy profit. A world-view that seems highly constrained by its intrinsic confirmation bias.
The above should read 'some' economics based thinkers. I wouldn't want Tim C. to think that I thought all economists are as dim-witted as he.
Those of us who enjoy DD's rantings need to know where to buy a secret re-emvowler ring to give to TC for Christmas
Re #60:
1. "If all CO2 sources from anthropogenic causes were immediately curtailed the system would continue to seek equilibrium at higher temperatures than we now experience, driving down the uptake rate until it approximately stabilizes at net zero." That is a cogent reason for not curtailing emissions of CO2. Moreover while it is not true that there were no anthropogenic emissions before 1750, if there ever was the equilibrium mentioned, it would presumably have been about then at or around 280 ppmv. That concentration is not enough to sustain modern agriculture.
2. "Ag production may well have benefited from warmer temperatures in the twentieth century". Er, not much, if the FAO, GISS, & Mauna Loa are to be believed. Regressing food production on CO2 and temps, we have adjusted R2 of .988, and the positive coefficient (1.75) on CO2 has a t stat of 30, so highly significant, while the temp coefficient is negative, pace #60, but not statistically signmificant at the 95% level. Of course there are other factors in agricultural production, above all precipitation, but the photosynthetic uptake of CO2 is the sine qua non. Point me to data on fertilizer usage and I will expand the regression. As atmospheric CO2 is well mixed, it is in principle uniformly available for all crops and forests, but that is not true of precipitation, so a more disaggregated regional analysis becomes desirable.
3. As for correlation and causality, the IPCC manages the latter without doing any of the former. Or are you arguing that it is food production that causes warmer temperature? But if the IPCC has cited global multi-variate regression analysis of all the variables we have discussed, please tell me where.
I, personally, think TimC uses Deltoid as a FUD test bed to pretty up his ridiculous ideas, in order to make them palatable.
The FUD phrases are false on their face, so the exercise is like putting lipstick on a pig. Goth, black lipstick and too much mascara too.
Best,
D
Tim C.,
If anthropogenic CO2 was curtailed the equilibrium would resolve at 380ppm+, not at some arbitrary previous equilibrium. At least for the next several centuries.
Correlation for any single cause relative to any single effect among a suite of non-linear coupled feedbacks is not likely to be very high.
Gah, your prose is turgid.
re #65.
The oracle has spoke: "Correlation for any single cause [CO2 emissions]relative to any single effect [temperature change] among a suite of non-linear coupled feedbacks is not likely to be very high". Exactly, but do tell the IPCC.
Poor TimC - having to misstate things to maintain a failing ideology. Must cause one quite a bit of extra energy expenditure, all that thrashing about and teeth gnashing.
Best,
D
Tim C.
The IPCC already knows.
What's your problem?
"Carbon is often not a limiting nutrient for plants, nitrogen is. "
Indeed. If not, then we are making one huge error in producing vast quantities of high nitrogen fertilizer at the cost of vast quantities of energy in order to increase the productivity of our crops about ten fold.
re Ugly Mug @#65: "If anthropogenic CO2 was curtailed the equilibrium would resolve at 380ppm+, not at some arbitrary previous equilibrium. At least for the next several centuries."
Why is today's 381 optimal and the base for a new equilibrium? In fact NASA frankly admits it cannot predict the future behaviour of the oceanic sink (htttp:scieece.hq.nasa.gov/oceans/system/carbon.html). That is because "carbon atoms are constantly being cycled through earth's ocean by a number of physical and biological processes...". There is no law stating that only newly emitted carbon atoms are involved in these processes. "The flux of carbon dioxide between the atmosphere and the ocean is a function of surface mixing (related to wind speed) and the difference [between] the concentration of carbon dioxide in the air and water. The concentration in the ocean depends on the atmosphere and ocean CO2 partial pressure....temperature, alkanity, photosynthesis and respiration". None of these are likely to result in net nil uptake by the oceans merely because fossil fuel emissions cease, while there is still c760 GtC up there in the sky. The atmosphere's CO2 is well mixed, so it not just the new arrivals that get taken up, and with the growing population of land and oceanic organisms absorbing CO2 through photosynthesis, they will keep on taking up while they can. Any new equilbrium is therefore likely to be one of mass starvation as a result of atmospheric depletion.
If the IPCC AR4 WG1 is to be believed (Table 7.4, citing Friedlingstein et al 2006) the oceanic uptake will INCREASE if emissions are reversed (contrary to Bigg, CUP, 2003:101 who claims the oceans will become a source if emissions are reversed, thereby offsetting emission reductions). Perhaps none have read Ugly's textbook, but it seems we are as much doomed if we do cut emissions as if we don't.
Re #69, of course both nitrogen and CO2 not to mention H2O are needed for optimal yields. I asked Ugly for his data on fertiliser usage, but he failed to respond.
TimCurtin,
You never give up. Even if humans ceased our combustion of fossil fuels today, that would not mean a decrease in atmospheric CO 2 levels, at least not for many decades. Deterministic systems take a lot to alter, and thus exhibit profound 'lag' effects. Only at local scales do systems become more stochastic.
You write as if somehow human beings have to ability - let alone the right - to try to manage exceedingly complex systems whose function we barely understand. For the past several decades systems and population ecologists have been tirelessly working to try and unravel some of this complexity in order to better predict the consequences of human alterations of ecosystems and biomes across the biosphere. We've hardly gotten out of the starting gate. That's because ecological systems function in a decidely non-linear fashion, such that causes and effects are disproportionate. Moreover, we are trying to bridge innumerable scales of space and time, as well as incorporating a stupendous number of interactions between individuals, populations and communities into our models. Against this background you spew out this one-dimensional gobbledegook about CO 2 levels and plant yields. What about the consumer connection? What about soil pathogens? Insect herbivores? Have you ever heard of Cedar Creek? Or Biodepth? Obviously not, or you wouldn't be peddling the rot that you do.
TimC.,
"If the IPCC AR4 WG1 is to be believed (Table 7.4, citing Friedlingstein et al 2006) the oceanic uptake will INCREASE if emissions are reversed..."
Hardly. As per Table 7.4, column 6, ocean carbon storage sensitivity increases by 0.8-1.4 GtC/ppm CO2 increase. Stopping CO2 emissions (0 ppm increase) would mean zero increase in ocean uptake.
OTOH, since there is an estimated .5C of cumulative warming yet to manifest over the next 30-60 yrs. due to previous increases of atmospheric CO2 concentrations, ocean sensitivity to temperature would give us (from column 8) a net atmospheric gain of 7.5-22.5 GtC from ocean sinks.
Since you are apparently adversely challenged by words and numbers, here is a pretty picture to help you understand some relevant equilibria stabilizations.
#72: That is indeed a very pretty picture, and affords every justification for all of us including especially the Chinese to do nothing to reduce emissions, as that will have no impact on temperature, sea-levels, and atmospheric CO2 for hundreds of years. Bravo!
72 again: That graph you linked to also proves that your science is an amazing reversion to the flat earth hypothesis pre Cristofero Colombo. True enough, you merely parrot John Houghton (TAR, and 2003:39) with his statement that "Suppose for instance that all emissions into the atmosphere from human activities were suddenly halted [as will be demanded at Bali]. No sudden change would occur in the atmospheric concentration, which would decline only slowly. We could not expect it to approach its pre-industrial value for several hundred years". Grant Bigg (in The Oceans and Climate, 2nd edition, 2003) makes nearly the same statement: "if atmospheric CO2 levels were suddenly decreased, then the oceans would slowly leak carbon dioxide back into the atmosphere, acting to push the climate back to its previous state [sic]" (p.101). A friend of mine here at ANU (Canberra) who contributed to the last 3 ARs of the IPCC concurs: "a declining atmospheric concentration leads to emission by the biosphere". So as #72's pic puts it, CO2 goes up (or at best stays the same) whether we reduce emissions or not. No wonder the IPCC offers no multivariate regressions. Is this irreversible CO2 trend plausible? I think not. Note that the Mauna Loa measurements of the atmospheric concentration of CO2 show intra-annual variation of as much as 6 ppm, with a max in April-May of (on average) about 6 above the min in Sept/Oct. If the above luminaries are to be believed, the decline between NH spring and autumn is exactly matched by an increase between Sept/Oct and April/May that is wholly independent of anthropomorphic emissions, such that the increase in manmade atmospheric concentration only occurs in a spurt round about March 31st. O tempora, o mores!
TC, unless you intend to eliminate the northern hemisphere winter, the annual variation of mixing ratio as measured at mauna loa remains. it is completely driven by the spring bloom. Interestingly, this variation is not nearly as strong in the southern hemisphere records since the south is much more liquid and the land there tropical. Some time ago, I got interested in this and tried to plot the ML annual variation vs year to see if there was an effect. There was nothing worth talking about.
It says no such thing, Mr. Curtin.
Please tell me that dishonesty isn't a prerequisite for a career in economics ...
TimC,
May I humbly suggest the spring max. and fall min. measures for CO2 have both been increasing upwards annually and that is the proper measure of AGHG accumulation. Also, there is a significant diurnal variation in CO2 that varies annually; daytime CO2 goes up in the winter, down in the summer.
Rather than wait to hear what incredible conclusions to which you will almost certainly leap based on this factoid, may I offer this curious piece of, AFAIK, unpublished (except on the internet) speculation by, apparently, a commercial hydrologist concerning correlation of CO2 and temperatures:
Summary
The audience now sits quietly in the amused expectation of much wild quacking, spewing forth, metaphysical hair-pulling, hand-waving and gnashing of teeth.
"Please tell me that dishonesty isn't a prerequisite for a career in economics ..."
May I suggest it is not, but in certain circles, self-delusion is a guarantor of career advancement. It makes transmitting of lies infinitely more palatable if one, a priori, believes supply and demand is THE central organizing principle of the Universe, holding ultimate sway over such insignificant factors as, say, ecosystem dynamics and the laws of physics.
This puts ravers/bloviators/wankers like TimC more into the category of socially rewarded pathological liars rather than your garden variety prevaricator.
Re #77. The non-peer-reviewed paper by Tangborn mentioned there by LB appears to have produced some spurious correlations. A more interesting and peer-reviewed paper just out in Journal of Geophysical Research (vol.12, D24S03) is that by Nicola Scafetta and B J West. The paper's link is available at Climate Audit.
The opening comment in #77 ("May I humbly suggest the spring max. and fall min. measures for CO2 have both been increasing upwards annually and that is the proper measure of AGHG accumulation") is true up to a point: over the years from 1959 to 2006 the trend increase is only from 5.5 to 5.9, while this range much exceeds the annual increment (1.6 from 8/06 to 8/07. But if LB is right that an increase in the annual range from 5.5 to 5.9 is "the proper measure of AGHG accumulation", what is his problem?