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Via Chris Mooney, who hits the usual theme of how the media gives climate change skeptics too much credit, comes this interesting story about the effects of climate change on the American West:

Warm Climate's Effects Striking In West

... Forget talk of global warming and speculation of what it might do in 50 years, or 100. Here and across the West, climate change already is happening. Temperatures are warmer, ocean levels are rising, the snowpack is dwindling and melting earlier, flowers bloom earlier, mountain glaciers are disappearing and a six-year drought is killing trees by the millions.

... The West is unique in that it depends so heavily on snowpack — melting snow provides three-fourths of the water in streams. Over the past 35 years, temperatures across the region have inched up 1 to 3 degrees, causing the snow to melt as much as three weeks earlier, said Kelly Redmond, regional climatologist for the Western Regional Climate Center in Reno, Nev.

Lilac and honeysuckle bloom up to 10 days earlier. Warmer temperatures lead to a huge surge in woody plants that thrive in warm, wet conditions. Glaciers are retreating, roads are buckling in Alaska and shifting some supports on the 800-mile trans-Alaska oil pipeline. Already-low reservoirs are called upon to water fields and quench thirst for longer and longer periods after the seasonal snowpack is gone.

Reducing the human impact on climate is important, and if the problems hitting the West can get people to wake up to the problem, so much the better. But I think there's another important issue here that gets lost in the framing of this as a question of "is it natural or anthropogenic": the American West is not a resilient system.

We now know that ecosystems don't have stable climax conditions. They experience a great deal of variability in various flows and states. In order for particular organisms or assemblages to survive in such changing conditions, they need to have a certain amount of flexibility and buffer capacity in order to be able to roll with the punches -- a quality ecologists call "resilience."

Modern American culture, however, is rooted in assumptions about a very limited range of environmental variability. Our implicit cultural experience is based largely on a short time frame (a few hundred years) in northeastern America and northwestern Europe, two of the least variable ecosystems around. So we have an attitude that nature can be predicted and controlled, that we can see our carrying capacity and make full use of it. This works well enough for a while. But transplanted to the West -- which is a munch more variable environment -- it's a recipe for disaster.

Take water flows. Water is in short supply in the West, and growing more so as population grows. So people have developed systems of property rights to divvy it up. But those rights are established based on assumptions about how much water will be available. Because nobody is willing to lower their use or allow some water to be "wasted" in good years, everything is claimed (and then some -- the US has for years been failing to allow enough water to flow down the Colorado to meet Mexico's entitlement). When inevitable drought years hit, there isn't enough water to fill everyone's entitlement. But the rest of the system has grown up on the assumption that a certain amount of water will be available. Municipal budgets are strained, water-using businesses find their activities curtailed, and the effects potentially reverberate through the system. Perhaps they can get some sort of bail-out from those of us who don't have a water crisis, but that just props up the unresilient social structure.

It took half a century of boom-bust cycles for Australian sheep ranchers to learn not to treat good years as "normal." The West looks on course to get a harsh form of that lesson. (Though the Aral Sea area is in even worse shape, having built up a ludicrously unsustainable cotton industry during the relatively wet '80s and '90s.)

So yes, we need to stop human-induced climate change. But that will merely dodge one bullet aimed at the West. In the long term, we need to build a more resilient settlement pattern and economy.


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