Rumblings from mother earth

A striking new study (registration required) coming out of the permafrost regions of Russia shows market effects of arctic warming, with softening of the permafrost leading to disappearance of lakes.

Comparing satellite images made in the early 1970s to those from recent years, a team of U.S. scientists determined that the number of large lakes in a vast 200,000-square-mile region of Russia's Siberia diminished by about 11%, from 10,882 to 9,712.

About 125 of the 1,170 shrunken lakes disappeared altogether, and most are now considerably smaller than the study's baseline of 40 hectares, or about 99 acres, the researchers found.

If Arctic temperatures continue to rise, the scientists said, many of the lakes in high northern latitudes, where they are ubiquitous, could eventually disappear.

"An 11% decline may not sound like much, but in the time-scale in which landscapes naturally change, this is extraordinarily fast," said the paper's lead author, Laurence C. Smith, an associate geology professor at UCLA.

Similar changes are being seen in Alaska, where glaciers are receding and roads and houses being ripped apart by shifts in the earth as permafrost melts. Inuits in that area have been noticing increasingly unreliable ice over the last decade as well, and scientists planning to study ice floes have found them much thinner than when planning for their research began. (See this lengthy but gripping New Yorker article for more.)

These changes in the arctic regions are even more significant than merely as first indicators that warming is real -- in fact, the melting of glaciers and deep frost releases more greenhouse gas (from long-buried plant materials that rot), increasing the pace of change.

In parts of the Arctic, this is already happening. Researchers in Sweden, for example, have been measuring the methane output of a bog known as the Stordalen mire, near the town of Abisko, for almost thirty-five years. As the permafrost in the area has warmed, methane releases have increased, in some spots by up to sixty per cent. Thawing permafrost could make the active layer more hospitable to plants, which are a sink for carbon. Even this, though, probably wouldn’t offset the release of greenhouse gases. No one knows exactly how much carbon is stored in the world’s permafrost, but estimates run as high as four hundred and fifty billion metric tons. (from the New Yorker piece)

Furthermore, open water absorbs more sunshine than does (highly reflective) ice, adding to the feedback loop toward more warming.

To put it simply, global warming isn't an issue we can leave for future generations to address. The ball is already rolling, and we need to head it off by decisive action before the immense momentum of natural cycles takes over and laughs at our puny protests.