Researcher Sees Biological Regime Change Under Way in Alaska

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http://www.scientificamerican.com/article.cfm?id=researcher-alaska-biological-regime-change

Researcher Sees Biological Regime Change Under Way in Alaska

Is climate change pushing Alaska toward another major abrupt shift, similar to the transition from grassy steppe to peaty tundra that took place thousands of years ago?

By Lauren Morello | December 10, 2011

SAN FRANCISCO -- Sixteen thousand years ago, woolly mammoths, Beringian lions and short-faced bears roamed a grassy steppe that stretched across North America into Alaska.

Two thousand years later—the equivalent of an eye blink in geologic time -- the animals were extinct in the area that is now Alaska. The grasslands had been replaced by peaty soil covered with moss, sedge and lichen.

Scientists presenting new research here at the fall meeting of the American Geophysical Union say warm, wet conditions helped flip the switch that turned the mammoth steppe into the Alaskan tundra of today -- and that episode hints at how rapidly an ecosystem can transform.

The question they're asking now is whether climate change is pushing Alaska toward another major biome shift, similar to the abrupt transition from grassy steppe to peaty tundra that took place thousands of years ago.

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