Another vote for 350 ppm

Al Gore has joined the growing list of notable climateers calling for a new target for atmospheric carbon dioxide concentrations. Speaking at the Poznan climate change gabfest this week he said we need to aim for no more than 350 parts per million.

The best known climatologist advocating such a low target ;;;; remember we're at 385 ppmv now ;;;; is NASA climate science chief James Hansen, who is the lead author on a recently published paper that identifies that specific number as the low end of a range of values associated with a climate regime shift between a world dominated by ice and one without. In other words, it was when CO2 levels fell below 450 ppmv +/- 100 ppmv that ice caps and glaciation began rapid growth a few million years ago. So, goes the theory, kicking them up to that level could trigger massive melts and consequent disastrous sea level rise.

Also on the 350 bandwagon is activist-author Bill McKibben, who has even organized an entire movement behind it:

There are those who think that such a target is so far beyond doable that we shouldn't try. Joe Romm at says 450 is more realistic. But Joe, despite his fabulous grasp of just about every angle of the issue, doesn't try to justify his chosen target on climatological grounds. He just says there's no way we can get to 350. This has always struck me as a bit odd. Because if 450 is doable but still results in catastrophic climate change, then what's the point?

Other agree that 350 is probably not possible. Stephen Chu, who's going to be Barack Obama's energy secretary, told an audience a year ago that getting below 500 ppm probably won't happen.

Here's Bob Watson, former head of the IPCC, in another Guardian story:

"We must alert everybody that at the moment we're at the very top end of the worst case [emissions] scenario. I think we should be striving for 450 [ppm] but I think we should be prepared that 550 [ppm] is a more likely outcome." Hitting the 450ppm target, he said, would be "unbelievably difficult"

And from the same Guardian story:

A report for the Australian government this autumn suggested that the 450ppm goal is so ambitious that it could wreck attempts to agree a new global deal on global warming at Copenhagen next year.

And here's the final paragraph from The Guardian's coverage of Gore's announcement at Poznan:

Earlier this year, Kevin Anderson, a climate expert at the Tyndall Centre for Climate Change Research at Manchester University, said it was "improbable" that levels could be stabilised below 650 ppm, because of booming carbon emissions since 2000.

Anderson's a fine fellow, but we'd better hope he's completely wrong, because 650 ppm would almost certainly not leave much habitable space on Earth.

But enough pessimism.

It's important to know that Hansen's proposed pathway toward a carbon-free economy involves more than one target. He fudges a bit on the actual schedule (and who wouldn't, given the uncertainties?), but what I can glean from reading his writings is 350 ppm is the long-term goal, one that we need to reach in the neighborhood of 2100. We can overshoot that, to say 450, in the short-term, but after say, 2050, we'd better be working hard to bring it down to 350.

Hansen says we could get to 450 through emissions reductions (shutting down all coal-fired power plants by 2030, etc.) and then use changes in forestry and agricultural practices to suck and sequester enough CO2 to get us down to 350.

That sounds like a plan. But Gore and McKibben and others will need to be specific about their short and long-term targets, and they're probably going to need more climatologists to publicly endorse those targets. Hansen's a good man, and he's not alone. But so far, few other prominent figures in the field have embraced 350 ppm.

One more thing: It seems to me that the difference between what it will take to get rid of most of the carbon in our economy and what it will take to get rid of all of it probably isn't all that significant. Either way, we're going to need massive shifts in technology and behavior. Indeed, I would argue that the changes required to keep us below 450 are so dramatic that they're probably be enough to go all the way to 350. But that's a not scientific observation.


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As I write, I can almost here the sock drawers being slide open.

Sock Puppet Denier: It is awfully cold here in Wackaloon Land today!

Me: Go learn the difference between weather and climate.

Sock Puppet Denier#2: Al Gore is fat! Al Gore uses electricity!

Sock Puppet#3: Sock Puppet#1 and #2 are brilliant! Clearly the smartest guys on the intertubes.

Me: Your using an Ad hominem and attempting to distract from the fact that your utterly clueless about the difference between weather and climate.

Sock Puppet#1 Science is STOOPID! It is no different than religion.

And round and round the self-congratulatory moron goes.

By Trent1492 (not verified) on 12 Dec 2008 #permalink

One more thing: It seems to me that the difference between what it will take to get rid of most of the carbon in our economy and what it will take to get rid of all of it probably isn't all that significant.

I suspect that the old 80:20 rule applies (you can get about 80% of the way to your target for 20% of the total cost).

But that is also not a scientific observation.

"650 ppm would almost certainly not leave much habitable space on Earth."

It's really bad, but not as bad as that. Recall among other things that the heating will occur preferentially toward the poles. The northerly shift of desert zones will be bad, but some areas (e.g. the Sahel) will probably benefit from increased rainfall.

By Steve Bloom (not verified) on 12 Dec 2008 #permalink

skwonk skwonnk. "We", including noted climateer and docudramtist Al Gore ("our" lord and saviour in the Church of Climate Religion), should always expect promote create and infer the worst. "We" of course have a computer model that has repeateadly been re-written using the rear view mirror to support our hoax err I mean science. skwonk skwonk. "Our" whole approach is verrry scientific you know. And it gives "us" a cause and something to do so we can feel good about ourselves. skwonk. That whole save the seals and trees thing was getting old and boring anyways and it was hard to scare and intimidate the mass of dummies. skwonk skwonk. I, too, remember the big Global Cooling scare. That was a big joke hoax farce also just like (cue up scary music) MANMADE GLOBAL WARMING. skwonk. skwonk. Join the church today, we have a two-for-one special today. Twice as much guilt for only one year's worth credits for carbon. Join today and experience the se-righteousness and self-fulfillment you can only get from the Saint himself. Gore Bless everyone. skwonk. Off to play computer games, err, I mean play with my theoretical climate model joke.

By Trent 911 (not verified) on 12 Dec 2008 #permalink

Your getting more incoherent as time goes by, Sock Puppet. Oh, btw, you got that info on difference between climate and weather? No? I thought so.

By Trent1492 (not verified) on 12 Dec 2008 #permalink

Weather is what is caused by MANMADE GLOBAL WARMING that is destroying the climate (and causing all this cooling over the past 10 years) and eventually (in 2050 according to the top secret "computer models") will cause death and destruction in an alarming manner if "WE" don't impose the lefty loonies' moral prerogatives. Everyone knows that. Remember that big GLobal Cooling scare? same thing. Oh...and things will get worse before they get any better because that makes us feel like we have an important missioin in life.

By Trent 911 (not verified) on 13 Dec 2008 #permalink

Have you tried reading your own posts? They are utterly unreadabe. Perhaps you should get aquantend witht the concept of the period and paragraph. Oh, and did you ever bother to look into the difference between climate and weather? Thought not.

By Trent1492 (not verified) on 13 Dec 2008 #permalink

We need this recession to deepen in to a extended depression. This is the only hope.

Trent911, hopefully you experienced the 08 ice storm in New England recently. Just what does Trent911 know about effects of increasing CO2 levels? Voila~! Ketchup and relish are vegetables!

Skuankers! Global Warming Church services were awesome this morning, although it was quite cold (due to all the warming obviously). You could smell the CO2 in the air. Reverened Gore was quite stunning and afterward all of us AGW parrots went out for a vegan breakfast. Skwaunk skwaunk. At breakfast, the AW parrots discussed the difference between 'your' and 'you're'. Maybe when Trent gets to 3rd grade english he'll learn that too. skwaunk.

By Skwuankster th… (not verified) on 14 Dec 2008 #permalink

Trent1492 dude relax. No need to be so defensive about your belief system. You can believe in whatever you want. Rock on buddy. Your pal, The Easter Bunny

By The Easter Bunny (not verified) on 14 Dec 2008 #permalink

So the new armageddon date is 2030 not 2050? This global warming stuff is really confusing. We need to agree on something specific like 382.5 ppm of CO2 plant food and say maybe 2032. yep. Those would be some good arbitrary numbers pulled out of the air just like all the others. That way while we're spinning on our eyebrows about our latest made-up enviro-crisis, we'll at least look coordinated.

By Your Mother (not verified) on 14 Dec 2008 #permalink

@Sock Puppet,

How can anyone take you seriously when you do not know the difference between weather and climate and refuse to learn the difference?

Trent911, hopefully you experienced the 08 ice storm in New England recently.

Again, please go learn the difference between climate and weather. Once you have done that, then you will learn why people who are informed laugh and point at the likes of the above quote.

By Trent1492 (not verified) on 14 Dec 2008 #permalink

What is the difference between weather and "climate change". The difference, obviously occording to that Trent chick, is that weather can vary, but, of course, Trent is capable of stopping the climate from changing ever (oh, perfect!!!). The Trent girl controls (or thinks she can) the global thermostat because she has ruled the earth for 3 million years and has translated that knowledge into a "theoretical computer model". Thus, the climate will be as of today at noon, never changing. And thus everyone, there is Trent's difference between the weather (which changes) and her climate (which will be forever frozen in time by driving a smart car). Voila'. Bless our lord our saviour Al gore and Ms. Trent. Welcome to the church of CO2 plant food. Cookies and Milk in the lobby after the service - help yourselves. Remember one lesson if nothing else - THE CLIMATE MUSt NOT CHANGE UNLESS Ok'd by STuPID Self Righteous LIBERAL IDIOTS. p.s. I'm going to personally set the earth thermostat at 72 degrees F tomorrow, so we have one cool day left anyways. p.p.s did anyone notice James' lame citation of ppmv vs ppm thingy. what a joke. What is V anyway. I'm so dumb I can't figure it out. I wish I weren't Trent's smelly sock. Maybe his mom will come down in the basement tomorrow and wash me.

By Miss Snark (not verified) on 14 Dec 2008 #permalink

I'm not really sure I understand what Climate Change is. Isn't it a general catch-all phrase used by smug arrogant liberal dweebs to refer to some vague doomsday that they say they are always self-righteously trying to avert, but don't have any hard data on, only farced-up computer models???

Isn't the IPCC definition a complete joke? Climate God keeps ridiculing it because it is a circular definition in that it apparently uses or references the term itself to try and define the term. Which would be classically stupid, but I don't suppose anyone really cares, except maybe that Trent gal.

I think most of the climate hoaxers probably want as much wiggle room as possible, you know, so they don't always look like buffoons with egg on their face, when none of their dire predictions come true. The temperatures are supposed to be going up, not dropping, the oceans were supposed to die decades ago, sea levels are supposed to be rising and flooding coastlines etc. etc., ho hum, yawn.

It doesn't matter how evidence or events run contrary to their doomsday predictions, they stilllllll desperately cling to their faith, and Al Gore. No matter where we are in history, the tipping point to doomsday is always 50 years out. They are going to blame it all on mankind no matter what, because they are just like that, and that is what they live for I guess. It's all about the climate jihad. If you oppose them, you are just a dehumanized dirty sock, as far as they are concerned.

By BA Baracus (not verified) on 14 Dec 2008 #permalink

Im not really sure I understand what Climate Change is.

Of course you do not. Is that going to keep you from making a horses ass of yourself? Of course not.

Isn't it a general catch-all phrase used by smug arrogant liberal dweebs to refer to some vague doomsday that they say they are always self-righteously trying to avert, but don't have any hard data on, only farced-up computer models???

Nope. Why are you such a coward on this issue? Why do you erect transparent strawmen that no one but you believe?
What keeps you from looking it up? Why do you not sit back in that special padded room your in and contemplate that for a moment.

Isn't the IPCC definition a complete joke?

How would you know since by your own admission in the first sentence you do not know what climate is. But why do you not go to the IPCC reports and paste up their definition. Then let us compare how that definition stacks up against say such professional organizations as the World Meteorological Organization.

temperatures are supposed to be going up.

They are. All of your childish assertions to the contrary do not make it so. So stop putting the finger in your ear and listen.

I think...

That is the problem: you do not think. You just regurgitate right wing talking points. You do not have that courage to think of Rush Limbaugh. Evidence your refusal to look up the difference between climate and weather.

No matter where we are in history, the tipping point to doomsday is always 50 years out.

Ignorance. I have already given you the empirical evidence. Your response? Silenence.You think no else notices the hloud silences on your part? Really?

By Trent1492 (not verified) on 15 Dec 2008 #permalink

This sentence: You do not have that courage to think of Rush Limbaugh.

Should be this one: You do not have that courage to think independently of Rush Limbaugh.

Misspelled: Silence

By Trent1492 (not verified) on 15 Dec 2008 #permalink

All you believers, witness your typical parroting spokesperson and be proud - Trent. skwawk.

By Skwawkie the P… (not verified) on 15 Dec 2008 #permalink

What's the new tipping point today? Remember it needs to always be just a little higher than todays trace-levels of plant food in the air, and always some arbitrary number of years away so that we can keep the hoax going. -Tippy

By Tippy the Tipp… (not verified) on 15 Dec 2008 #permalink

Once again, please note that the Sock Puppet, refuses to discuss anything substantial. That when he is cornered he simply retreats to more stupid strawmen and childish insults.

So why do you not address the Hadcru data I posted up? You are the one who moronically insists that temperatures disprove global warming. I am the one who provided hard data. Oh, have you learned the difference between weather and climate yet?

By Trent1492 (not verified) on 15 Dec 2008 #permalink

skwawk skwak I'm a global warming parrot so I'll focus my belief system on a hoax computer model to farce up an alarmist crisis that makes me feel good. I still believe, even though all four major global temperature tracking outlets (Hadley, NASA's GISS, UAH, RSS) now clearly show that global temperatures have dropped precipitously, enough to wipe out most of the warming recorded over the past hundred yrs. I choose to ignore that - or even better! - I will blame the cooling on warming because that makes perfect sense. And then I'll claim something bad will happen in 2050 due to cooling or warming or warming or cooling or both or whatever. If you take a ruler and draw a line from the temp in 1998 to the temp in 2008, oh wait, don't do that. hmmm must be MANMADE GLOBAL WARMING causing all this cooling that causes tipping points that causes warming that causes cooling - in 2050 of course. It all adds up and makes perfect sense. My model told me. skwawk. (what exactly is 'climate change' anyway) skwawk.

By skuwonkie the … (not verified) on 15 Dec 2008 #permalink

For how many years must the planet cool before we begin to understand that the planet is not warming? For how many years must cooling go on?" - Geologist Dr. David Gee the chairman of the science committee of the 2008 International Geological Congress who has authored 130 plus peer reviewed papers, and is currently at Uppsala University in Sweden.. . . . . . . Gore prompted me to start delving into the science again and I quickly found myself solidly in the skeptic campClimate models can at best be useful for explaining climate changes after the fact. - Meteorologist Hajo Smit of Holland, who reversed his belief in man-made warming to become a skeptic, is a former member of the Dutch UN IPCC committee.. . . . . . . . Many [scientists] are now searching for a way to back out quietly (from promoting warming fears), without having their professional careers ruined. - Atmospheric physicist James A. Peden, formerly of the Space Research and Coordination Center in Pittsburgh. Trent - Let me know when your head explodes and I'll stop..........

By Yer Mother (not verified) on 15 Dec 2008 #permalink

I'd just be happy if someone could define 'climate change' without using the words climate and change, or using a circular argument or the number 2050.

Gosh Trent, you are such a cowgirl. Nobody but you cares about guessing your definition of Climate Change. Its obvious to everyone that you only care about defending your faith by stoking a flame war. You appear to be way too smug and arrogant to care about the public good. As such you are the perfect representative to defend the AGW jihadists. It is people like you that have turned science into nothing but disparaging arrogant alarmist propaganda in support of your faith. Keep it up. Soon scientists will be ranked alongside lawyers for lack of credibility and affection.

642 AM MST MON DEC 15 2008




By Weather Nerd (not verified) on 15 Dec 2008 #permalink

The models and forecasts of the UN IPCC "are incorrect because they only are based on mathematical models and presented results at scenarios that do not include, for example, solar activity. - Victor Manuel Velasco Herrera, a researcher at the Institute of Geophysics of the National Autonomous University of Mexico. . . . . . . . It is a blatant lie put forth in the media that makes it seem there is only a fringe of scientists who dont buy into anthropogenic global warming. - U.S Government Atmospheric Scientist Stanley B. Goldenberg of the Hurricane Research Division of NOAA. . . . . . . . . . Even doubling or tripling the amount of carbon dioxide will virtually have little impact, as water vapour and water condensed on particles as clouds dominate the worldwide scene and always will. . Geoffrey G. Duffy, a professor in the Department of Chemical and Materials Engineering of the University of Auckland, NZ. ........"It sux to be me." - Trentiwannabeacowgirl1492, Island of Doubt AGW alarmist fringe whacko website.

By The Professahhhhhh (not verified) on 15 Dec 2008 #permalink

Anybody going to CO2 church tomorrow? I need a ride.

By You can call me Al (not verified) on 15 Dec 2008 #permalink

Apparently the sock puppets have multiple personalities - all of them annoying.

Can we please kill the trolls - Rabett style?

Dec 16th. Freezing air blanketed much of the nation Tuesday, making roads hazardous in Texas and slowing recovery from ice storm blackouts in New England, in the second day of a bitter cold wave.

Temperatures were 20 below zero and lower across the northern Plains, and a band of global warming, freezing rain and sleet stretched from Kansas along the Ohio Valley to Maine.

Dozens of schools closed in Kentucky and Tennessee because of slippery roads and salt truck crews started working before dawn. Up to a half-foot of global warming had fallen in parts of Kentucky. Police in North Texas had to close some highway overpasses because they were so slippery with global warming.

Some of the sharpest cold Tuesday was in northern Minnesota, where Hibbing bottomed out at 32 below zero and International Falls dropped to 28 below. In the middle of the state, St. Cloud fell to 24 below, breaking its old record of 21 below set in 1963.

The weather service posted Global Warming Warnings Tuesday for parts of the Southwest where New Mexico had numerous school closings, including those in Albuquerque and the Ohio Valley. Global Warming Advisories were in effect across the Midwest and from Texas to New England, where utilities were still repairing power lines snapped by last week's devastating ice storm.

By Weather Nerd (not verified) on 16 Dec 2008 #permalink

MikeB - If we are going to kill the trolls, I suggest we burn them at the stake, like the heretics they are. It will be an example to others, to keep the faith, or suffer the painful consequences. We can probably rig up solar ovens for this, so we don't use fossil fuels to dispose of them. How dare those infadels call us Jihadists!

By Manny the Dominican (not verified) on 17 Dec 2008 #permalink

In my opinion the largest threat for California are cataclysms and ecological catastrophes. Not important is how many money we have because one tragedy can us take all.