In his first post-retirement essay, a remarkable communication, James Hansen summarizes his position, and announces that he will get more science done in his retirement, not less.
His point of view on the physics is:
Climate system inertia means that it will take several centuries for the eventual extreme
global warming mentioned above to occur, if we are so foolish as to burn all of the fossil fuel
resources. Unfortunately, despite the ocean’s thermal inertia, the transient climate phase this
century, if we continue business-as-usual fossil fuel burning, is likely to cause an extended phase
of extreme climate chaos. As ice sheets begin to shed ice more and more rapidly, our climate
simulations indicate that a point will be reached when the high latitude ocean surface cools while
low latitudes surfaces are warming. An increased temperature gradient, i.e., larger temperature
contrast between low and high latitudes, will drive more powerful storms, as discussed in
“Storms of My Grandchildren”.10
I think it’s pretty much becoming clear that the chaos has begun. The above leaves me with the impression that Hansen is proposing a somewhat different mechanism than the Francis/Vavrus one, and one that seems to me at least more satisfying at first blush.
This sort of brings back the old Broecker “Unpleasant Surprises in the Greenhouse” scenario, that got blown up into scary sudden ice-age scenarios. There will be a tug-of-war between Greenland melting and polar waters cooling. I propose that cold-season sea ice will not decline very much, and perhaps even increase. This fits in with what we are seeing in Antarctica that the confusion squad is so quick to jump on.
But his de facto non-retirement is also worthy of note as much as his de jure retirement:
I also realize that the interview I gave regarding my retirement may have left the
impression that I would now be working mainly on specific actions to stem fossil fuel extraction
and use. I believe all the individual actions occurring at many places are very important and the
sum of them may help turn the tide to clean energies. But I must keep up with and contribute to
climate science or I cannot be effective, so I hope to be doing more science rather than less — and
science requires more than 40 hours a week –so it is not practical for me to respond to all the
requests that I am receiving.
So Hansen joins Muller and pioneer Peter Gleick as a scientific entrepreneur. Are conventional scientific institutions in decline?
I also want to support two or three people working with me, so I
need to spend time in fund raising – and I am finding that it is not easy to get foundation support.
Finally, as a new non-government-employee he allows himself a little poiltical snark:
. I will continue to support the growing 350.org movement. I support
CitizensClimateLobby.org especially, because of their focus on fee-and-dividend, which I
believe is the sine qua non for phase out of fossil fuels. I hope you noticed the op-ed supporting
fee-and-dividend in the Wall Street Journal by George Shultz and Gary Becker, who point out
that fee-and-dividend plus removal of energy subsidies would provide a level playing field and
be good for the economy and jobs. There is also a Democratic (Boxer/Sanders) bill in Congress, 7
but as usual they cannot keep their hands off our wallets, proposing to take 40% of the money to
make government bigger, including congressional specification of how 15% of the money is to
be spent. Washington seemslikely to remain dysfunctional on climate policy, so when we get a
bit closer to 2016 I will argue why I think we need a third party. In the meantime we must try to
do what we can with what we have. Somebody with access to the President should wake him up
to the implications of going down the unconventional fossil fuels route (I have tried, but failed to
get access). He will have a heck of a lousy legacy if he takes the big step down that road with
the Keystone pipeline. This is an area where he could reach across the aisle,suggesting that he is
open to the idea of a revenue neutral carbon fee, which would save much more carbon than the
Keystone pipeline would carry, but he would have to give up the Democratic penchant for telling
us how to spend our money.