Saturday, November 1, 2008

Methane on the uptick

The market may have gone down, way down, to be followed by a period of volatility, but atmospheric methane is going up, after a period of relative stability. This according to Matthew Rigby and Ronald Prinn of MIT.

This is important because it relates to Jim Hansen's (and others') working hypothesis that even a small rise in average annual temperature puts us within closer reach of various possible/hypothetical climate system tipping points than otherwise thought.

One tipping point might be northern hemisphere methane release. Not methane clathrates. (Those are even scarier, almost too scary to think about.) Just plain old bacterial methane from anearobic decomposition in actic and subarctic soils, particularly wet soils, peats, and pond and lake sediments.

AAT increases (the theory goes), heating up northern landscapes more typically too cold or frozen to decompose very fast. But the nutrients, bacteria and moisture are all there, primed and ready to go. Decomposition increases, releasing more methane, increasing AAT.

Rinse and repeat. Otherwise known as feedback. "Feedback can lead to exponential change," I teach my students, and then show them how, ad nauseum, with model after model in Stella ®.

(Even then, most don't get it. Ordinarily, even when taught well, and over and over, many people fail to understand exponential feedback.)

If atmospheric methane is increasing as stated in this new paper (very likely), then it has to come from somewhere. Most likely it comes from the warm Siberian summer of 2007.

Not good. A tipping point like this could ruin your pension plans even more effectively than the current market problems. The methane numbers bear watching closely for a few years. We should all cross our fingers and hope it's just stochastic, an anomaly.

There's a potential tipping point in my career as a climate mitigation academic too. At some point I would have to give up, and start teaching climate emergency management and climate change adaptation. And get busy adapting myself. (As if Aimee and I haven't really been doing that for years with our farming, gardening, forestry and building experiments.)

Abrupt climate change of the speed and effect envisaged by Hansen and others will create a new feedback loop in the climate system, or more correctly change the (mathematical) sign and direction of an old one, by effectively reducing our ability to feed, water, clothe, shelter, house, and keep safe some large portion of the human population.

Emissions from human sources will go down as a result, but it won't be a good thing, and it will be far too late. Unplanned, unreasonable, and distinctly uncivilized. Once out of balance, the global climate system could stay out of balance for quite a while.

Those governments that remain viable will be stretched to the limit.

The question is, in such a scenario, how quickly would we need to adapt, and in what sectors? The answer is, quickly, and in almost all sectors. A thought experiment might be helpful here. Taking the 2001 New England Regional Assessment as our baseline (essentially 6-10 degrees F of regional AAT increase by 2100), a tipping point that accelerated this rate of regional AAT increase by an order of magnitude would require Maine to adopt forestry, agriculture, fisheries, housing, extreme weather, and disease control strategies more like Virginia's or Georgia's before 2020.

This is assuming that there are no other system perturbations or tipping points down the road after the first. Just a more rapid AAT rise than currently predicted.

Sea level rise would lag, giving us a few years to cope there. That would be a blessing. but within a century, instead of a millenium, Jackson, Maine would be a peninsula or an island and Unity College would be the environmental college next to the Atlantic. Assuming there was anything left to teach.

I tend to think there would be. I think Maine could survive this with a democratic civil society intact. Assuming that we don't encounter major security concerns because of threats from countries who are less able to adapt.

Evidence for this: My parents and grandparents collectively survived WWI, the Great Depression, and WWII. They survived, and I survived, the Cold War, the socialist Britain of 1945-1979, the Maggie Thatcher capitalist Britain of 1979 to the present. I survived and adapted to this very different American culture. In my small experience, people are surprisingly adaptable. The twentieth century demonstrates this admirably, even in the case study of my small family.

Of course, other countries, and other people, did not do so well adapting to and surviving the period 1914 to 2000.

In the event of a tipping point, the 21st century will look politically a lot like the 20th, only worse. And there will be no Josef Stalin or Adolf Hitler to blame, only ourselves.

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