Saturday, November 8, 2014

We Are the Adaptable Ones

Climate change is about other species, not us.

While all the attempts to calculate the economic costs and benefits of climate change are well-meaning, I think they are mostly beside the point. Of all species on earth, we are the most adaptable, and can readily, if not easily, adapt to climate change. Even if adapting to it eventually costs more than solving it. While other organisms are fated to adapt on evolutionary time, by mutation and selection, (or die), we can adapt in cultural time. Cultural time is hugely compressed vs evolutionary time, as our last century of technical progress, and biosphere destruction, attest.

Earth has gone though very warm epochs in the past, where there were no ice caps, and Alaska had palm trees. And there were great changes to life as a result. But it was all very slow, giving time to the ecological network to adjust. Truly catastrophic events, like the end-Cretaceous asteroid impact, devastated the biosphere to a state that we would never want to see if we can possibly help it. If we have to move to Siberia to farm within a hundred or a few hundred years, we can do so, burning yet more fossil fuel to get there. Other species don't have it so easy.

So I think it is important to avoid, or at least go beyond, the economic, cost vs benefit calculus that many seek to put on the climate change debate. Our current biggest benefit is always to do nothing and hope for the best. The "discount" put on future human generations with respect to benefits they might get from our responsible behavior today is variable and highly subjective. If we feel like doing something for future humans, great. But in any case, we do not face extinction. Other species do.

"A large fraction of species face increased extinction risk due to climate change during and beyond the 21st century, especially as climate change interacts with other stressors (high confidence). Most plant species cannot naturally shift their geographical ranges sufficiently fast to keep up with current and high projected rates of climate change in most landscapes; most small mammals and freshwater molluscs will not be able to keep up at the rates projected under RCP4.5 [an intermediate mitigation scenario] and above in flat landscapes in this century (high confidence). Future risk is indicated to be high by the observation that natural global climate change at rates lower than current anthropogenic climate change caused significant ecosystem shifts and species extinctions during the past millions of years. Marine organisms will face progressively lower oxygen levels and high rates and magnitudes of ocean acidification (high confidence), with associated risks exacerbated by rising ocean temperature extremes (medium confidence)."
"Many terrestrial, freshwater, and marine species have shifted their geographic ranges, seasonal activities, migration patterns, abundances, and species interactions in response to ongoing climate change." 
- the IPCC
Future hothouses on earth, under two different scenarios, first a stringent mitigation scenario, and second a business as usual, high emissions scenario- also from the IPCC.

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