Tuesday, February 14, 2006

[Global Warming]

The Challenge of the 21st Century

The Pew Research center recently did their year-end "issues" report for 2005. Mirroring political inaction, none of the top ten issues on the list was global warming. Some of it was the usual flotsam that clogs public consciousness (be interesting to look back through the years and see what idiotic issues captivated us in, say, 1987)--Terri Schiavo, evolution--and some of it was more substantive. Yet despite pretty spectacular findings, the issue of global warming has been slow to stir our fear.

It is, nevertheless, the great challenge of this century. Depending on what we do in the next decade, the effects could be catastrophic. There's a lot of data out there (in almost every case, in various flavors of catastrophic), but to take one example, here are a few findings from the Union of Concerned Scientists about the changes that will effect California in the next century. The scientists looked at two scenarios: one charting effects if no changes in fossil fuel use, and one with reduced emissions. Both are grim:
  • By mid-century (2020-2049) summer temperatures are projected to rise 2-4 °F under the lower emissions scenario and 2.5 ­ 5.5°F under the higher emissions scenario.
  • Toward the end ( 2070-2099) summer temperatures are projected to rise 4-8.5°F under the lower emissions scenario and a dramatic 7.5-15°F under the higher emissions scenario.
  • Winter precipitation, which accounts for most of California's annual total, decreases 15 to 30 percent before the end of the century in three out of four model runs. However, in one model run, winter precipitation increases approximately five percent. These results differ from some projections developed using earlier models, which suggested that precipitation could double by the end of the century. The precipitation projections described do not differ between emissions scenarios.
  • Depending on the climate model used, sea levels could rise at a rate similar to the historical rate of about seven inches per century or almost four times faster. The rate is consistently higher under the higher-emissions scenario.
The effects of these changes will be severe. Drought, famine, and disease will emerge first. Habitats will change more radically than animals can adapt, causing mass extinctions. Already water rights through much of the West are matters of dispute. While Arizona may not declare war on Colorado over water, India's response to Pakistan and Iran's response to Iraq, to take two examples, might be more violent. Storms will wreak havoc. Economies will be wrecked; democracies will crumble; instability will flourish.

The shocking thing is that these aren't theoretical effects: they're almost certain outcomes. In best-case scenarios, they're just not as severe. How we respond will effect the worst of those changes. And, if there's some currently unforeseen way to mitigate the worst of the problems, we'd better be at work on it ASAP. But the truth is, our lives and our children's lives are going to be colored more by global warming than any other condition or event this century.

We must start taking it seriously.

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