Earth Equity News

Arctic Tundra Loss Quickens as North Warms. By Bill Sherwonit, YaleEnviro360, January 11, 2010. "Researchers have known for years that the Arctic landscape is being transformed by rising temperatures. Now, scientists are amassing growing evidence that major events precipitated by warming -- such as fires and the collapse of slopes caused by melting permafrost - are leading to the loss of tundra in the Arctic. The cold, dry, and treeless ecosystem -- characterized by an extremely short growing season; underlying layers of frozen soil, or permafrost; and grasses, sedges, mosses, lichens, and berry plants - will eventually be replaced by shrub lands and even boreal forest, scientists forecast. Much of the Arctic has experienced temperature increases of 3 to 5 degrees F in the past half-century and could see temperatures soar 10 degrees F above pre-industrial levels by 2100. University of Vermont professor Breck Bowden, a watershed specialist participating in a long-term study of the Alaskan tundra, said that such rapidly rising temperatures will mean that the 'tundra as we imagine it today will largely be gone throughout the Arctic. It may take longer than 50 or even 100 years, but the inevitable direction is toward boreal forest or something like it.'

"The transformation of the tundra -- the word comes from the Finnish, tunturia, meaning 'treeless plain' -- will have a profound impact on the creatures that live and breed there, including grizzly bears, wolves, foxes, and many species of waterfowl and migratory songbirds. Especially hard-hit could be caribou, which depend heavily on lichen as a food source. Increased burning and thawing of the tundra also is expected to accelerate global warming. Scientists point out that huge amounts of carbon -- and substantial amounts of methane, an even more potent greenhouse gas -- are tied up in the permafrost that underlies most Arctic tundra. Michelle Mack, an ecosystems ecologist at the University of Florida in Gainesville, notes that 'twice as much carbon exists in the world's permafrost as in the atmosphere. So as they melt, these soils will add immensely to the carbon dioxide in the air.'" Bill Sherwonit is the author of 12 books about Alaska.