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350 ppm
Alex Steffen, 2 Jan 08
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"The evidence indicates we've aimed too high -- that the safe upper limit for atmospheric CO2 is no more than 350 ppm," says Jim Hansen.

350: That is the level to which Hansen believes we need to reduce the concentration of carbon dioxide (and by implication, other greenhouse gases) in the atmosphere if we want to avoid a series of catastrophic climate tipping points.

The bad news? Atmospheric carbon is already at least 383 ppm, and the rate at which we're spewing greenhouse gases is increasing. In other words, we've seen the credible bar for achieving climate stability drop from 550 to 450 to 350 over roughly the last year. Bill McKibben walks us through the implications:

The difference between 550 and 350 is that the weaning has to happen now, and everywhere. No more passing the buck. The gentle measures bandied about at Bali, themselves way too much for the Bush administration, don't come close. Hansen called for an immediate ban on new coal-fired power plants that don't capture carbon, the phaseout of old coal-fired generators, and a tax on carbon high enough to make sure that we leave tar sands and oil shale in the ground. To use the medical analogy, we're not talking statins to drop your cholesterol; we're talking huge changes in every aspect of your daily life.

Carbon-neutral prosperity is possible. We can design and build a sustainable society within the time we have remaining. The matter hinges entirely on having the will to build it. And that's what's going to be tested now, and big time: our will.

Beyond the political barriers, though, I think there are some habits of mind that impede the gathering of that will.

The first is, as we've said here frequently, the lack of compelling and credible visions of what that society would look like. Without those visions, it is very difficult for any of us to seriously imagine transformational change. As Bucky said, "You never change things by fighting the existing reality. To change something, build a new model that makes the existing model obsolete." We need to cultivate a vision of a bright green future that is both bold and beautiful, that goes far enough and offers people better lives.

The second is that we are in overshoot and time is proving to be the strictest planetary limit of all. It's bad enough that with each passing day it becomes more difficult to attain a bright green future -- it's worse to know that things are going to get grim, no matter what we do. We have already committed ourselves to climate chaos, an extinction crisis and mass human suffering -- though what we do now will greatly determine exactly how awful each of those things gets, and if we act now, we can, in fact, still make it through the window of opportunity. To do that we need to be able to read the bad news and still remember that defeatism serves evil here, and in times like these, optimism is a political act. We need to cultivate a politics of optimism.

The third, it seems to me, is perhaps the most difficult: we need to come to understand that this is not a crisis that can be faced or solved on a personal level, and that, to succeed here, we need common action for the common good. We can't shop our way to sustainability; we can't take enough simple steps to get to a one-planet future; we can't save ourselves -- we can only save each other.

This is going to be hardest to accept here in the U.S., where lifestyle environmentalism has been shouted from every rooftop as the answer to our problems. It's going to take much more than a new president to hep Americans come to an understanding that the upper-middle class suburban lifestyle (to which many of us aspire) has become a thing of active evil, and no amount of technofix is going to change that -- we can't just change our lightbulbs and swap our hummers for priuses and call it a day. We're going to have to act together to redesign, reinvent, retrofit and re-engineer nearly every aspect of modern life, and we're going to have to do it in part through regulations, taxes, bans and fees, and we're going to have to do it quickly, and for those unready or unwilling to make the change it's going to hurt.

One the other hand, this moment also offers both the nation and us as people the greatest opportunity for reinvention we've ever had. Our economy is creaking with debt, technologically out-of-date and scandalously dirty, not even vaguely prepared to meet the challenges of 21st century bright green global trade; our political system is ossified with corruption and sedimentary layers of media spin and partisan lies; our suburbs hang suspended on the illusory promise of cheap oil while our cities have been neglected and mismanaged; much of our infrastructure is on the point of collapse; our child care, education and justice systems are the worst in the developed world; our military has been ground to pieces in a war for oil; our health care system no longer serves more than a third of our citizens; our farmlands are blowing away, our forests are burning and our rivers are drying up.

For nearly every one of these problems, there are existing or emerging solutions, and we're coming to realize that most of those solutions support each other in a healthy 21st century society. In holistic, innovative and ambitious answers lies our salvation. We can do this. But our lives won't be the same: this is like a war: whatever plans we had before are going, now, to change. We need to cultivate an awareness that this generation is called to do big things by seeing the big picture, serving the public good and working together.

The crisis we face places stark demands on us, and I can't think of better advice for meeting them than Alasdair Gray's motto, "Work as though you lived in the early days of a better nation."

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I got my street performer's license today. For my act, I put down energy and political performance art. Tried out one version of my show a couple of times already at a friend's stand with a portable solar fountain and have a variety of other show ideas on the drawing boards.

One thing I'm thinking of is using WWII posters like the one that reads, "Should brave men die so you can drive...?" and "Oil is ammunition" with a portrait of a dapper General Eisenhower and "Fuel Fights" with a list of energy conservation measures and "All Fuel Is Scarce" with a compendium of one of the best simple winterization plans I've seen. Top it off with my Solar IS Civil Defense catchphrase, attach the posters to a pole on a tripod in Harvard Square, and see what happens.

It's going to be an interesting time, especially for old farts like me who've been riding this hobby-horse since before 1973.

Posted by: gmoke on 3 Jan 08

Alex - it is good to see a rather more grave outlook published on World Changing than has been the norm.

While people undoubtedly do need the encouragement of potentially viable solutions to be emotionally capable of addressing the scope of the GW problem, our position is now so dire that specialist blogs like World Changing seem to gain little by glossing over the looming hazards.

In this light I must, with real respect, differ with Dr Hansen's proposed 350ppmv target as being poor politics rather than good science.

First, because, [as published in Nature a few years ago],
the cause of a ~6% annual rise in watercourses' Dissolved Organic Carbon [DOC] has been traced to elevated CO2's impact on the microbial ecology of peat bogs, causing the latter to decay. The carbon so released reacts to form CO2 which then outgasses asap.
The rate of growth of this obscure feedback loop will, if not reversed, outgass an annual tonnage of carbon equal to the entire current annual anthro output by about 2060.

This exponential rise in streams' DOC was first recorded in 1960, when CO2 was at only about 320ppmv.
We don't know the ppmv when this phenomenon got started.

Second, the prospect of stabilizing airborne CO2 (and some other GHGs) is a miasma, since we cannot begin to calculate, and predict, the outputs of the many feedbacks, large & small, even if we were able to achieve the required sudden changes in anthro outputs.

Thus the airborne GHG load will continue rising, or, with a true global commitment, it may one day be made to peak & then decline,
but it will never be "stabilized" (except, possibly, at its natural level).

This notion of "stabilization" is a political charade (employed to try to entice the reluctant into co-operation) that is very liable to backfire badly when the press start looking for scapegoats.

Therefore I greatly look forward to those with Dr Hansen's high profile urging the target, first, of capping the CO2eq ppmv (at as low a level/rapid a pace as will not actually break the global economy)
and, second, the target of restoring the pre-industrial CO2eq ppmv just as soon as possible thereafter.

This is a radically different outlook than "Stabilization at 350 ppmv", and I suggest it is precisely what our circumstances demand we strive for.

For those reading this who don't yet see the urgency, I'd recommend a look at the IPCC AR4, with its projection of some African nations losing 50% of their accustomed food production by 2020.

To put this climatic destabilization in perspective, please consider that the great historical famines in Europe arose from just 10% to 15% losses of food production.



Posted by: Lewis on 4 Jan 08

Alex, may I use part of this article in our Alabama Sierra Club Newletter? I will ensure you receive full credit and will boldly advertise your website.

Posted by: John Ackerman on 5 Jan 08


Seems like it is up to everyone to do what they feel
like to help ( or not to )help the environment.
It is undeniably a very serious and grave issue.
As government are meeting to discuss how to tackle the problem should they not include a maximum temperature on heating businesses and our homes ?
Having your home properly insulated also should be made a priority. A simple tax reduction when you have your certificate of Proper house insulation would do the trick.
Cars runing of highpolution should have a tax increase
while green cars should have tax reductions ! When is something like that going to happen !

Years ago I heard that there was an order made presumably by the French government ( as I was living in France then) that living spaces should be heated to no more than 19*C.
I was many years ago & I can not for sure say when and if the centigrade are correct.

The point here is I think such measures are necessary.
I now live is Asia. But I remember London was not better. For example . It is winter and when you go out you wear well. The moment you enter a department store you have to undress so hot it is in there. Of course poor sales lady would catch a cold wearing just a light shirt !!!
Or enter a bus and it is the same problem.. only in summer it is in reverse . The cooling air conditioning system is set so low you wish you brought your jacket !

Ok this may be just my point of view, many people are quiet satisfied this way , But it is unnecessary and damaging to our planet.
Therefore IF Proper regulations were introduced everyone would save on fuel while at the same time reducing global warming.

Please pass it on to Mr Al Core or other people of influence. Great web site I learn of it from a recent TV program.

Posted by: Didier on 5 Jan 08



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