Thursday, November 22, 2007

The way ahead

A transition from noncoherent, molecule-to-molecule heat transfer to coherent convection occurs in some heated fluids. During the process more than 1022 molecules come into concert. From a statistical point of view, this is ridiculously improbable. Yet the coherence arises naturally from an applied temperature gradient. Nature creates systems, sometimes quite complex ones, "in order to" get rid of gradients and export atomic chaos into the surroundings. "Centripetal," selflike structures arise from material cycles, energy-driven, self-reinforcing networks. Despite the term selfish genes, genes do not have selves: true selves are cells; without proteins and metabolic networks of recursive amino acids and intermediary molecules, genes are impotent, no more "selfish" than an unplugged toaster.
-- from Into the Cool: Energy Flow, Thermodynamics and Life by Eric D. Schneider and Dorion Sagan.

James Lovelock, who like Lewis Thomas and others, has compared the earth as a whole to a cell, says in his review of Oliver Morton's Eating the Sun:
The wonderful thing about science is that nature itself is always the final arbiter. In time, Gaia theory will be confirmed or denied by evidence from the earth. Unfortunately, we do not have time. The evidence so far suggests that the earth is now in rapid motion towards one of its hot stable greenhouse states, perhaps like that of 55m years ago.
So, what about surviving and thriving? Schneider and Sagan quote Alan Watts (although one might as well quote a proponent of systems theory like Peter Senge, who I think has observed something similar in real life):
A Taoist story tells of an old man who accidentally fell into the river rapids leading to a high and dangerous waterfall. Onlookers feared for his life. Miraculously, he came out alive and unharmed downstream at the bottom of the falls. People asked him how he managed to survive. "I accommodated myself to the water, not the water to me. Without thinking, I allowed myself to be shaped by it. Plunging into the swirl, I came out with the swirl. This is how I survived.
Fine so long as you don't hit your head on a rock. What rocks will there be on the way if/as the Earth switches from one stable state to another, as Lovelock suggests?:
When we change the carbon dioxide content of the air, the earth responds, when healthy, by neutralising our pollution—negative feedback. Now, less healthy, it responds by supplementing our increase with one of its own—positive feedback. The temperature increases rapidly with each addition of CO2 because, over a certain range, temperature and CO2 are directly related and soon the incremental heating from the earth itself will exceed our inputs and then further heating is unstoppable. Fortunately for us, earth history suggests that positive feedback will come to a natural stop and temperatures will stabilise five degrees above the present. The idea that we can stabilise rising temperature at some convenient level, say just two or three degrees above the pre-industrial norm, is probably the delusion of computer modellers. Once positive feedback starts, there may be little that we can do except try our best to adapt to a five-degree hotter earth. Hot enough to make our world a vast desert and starve most of us.
Agricultural practices can obviously adapt to some degree, but only so far.


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