YUKON DELTA NATIONAL WILDLIFE REFUGE, Alaska — The Arctic is warming about twice as fast as other parts of the planet, and even here in sub-Arctic Alaska the rate of warming is high. Sea ice and wildlife habitat are disappearing; higher sea levels threaten coastal native villages.
But to the scientists from Woods Hole Research Center who have come here to study the effects of climate change, the most urgent is the fate of permafrost, the always-frozen ground that underlies much of the state.
Starting just a few feet below the surface and extending tens or even hundreds of feet down, it contains vast amounts of carbon in organic matter — plants that took carbon dioxide from the atmosphere centuries ago, died and froze before they could decompose. Worldwide, permafrost is thought to contain about twice as much carbon as is currently in the atmosphere.