WHITEHORSE - Scientists say they've found evidence the North has now become a source of atmosphere-warming carbon dioxide. A new study from the Pew Center on Global Climate change says the Arctic tundra is no longer absorbing carbon dioxide, but it rather releasing it.
Scientists have estimated that soils in the Arctic have accumulated up to one-third of the entire earth?s organic carbon.
When the climate warms, carbon that had been locked in frozen peat and other permafrost zones is released through melting.
Camille Parmesan of the University of Texas says the tundra has changed from being a carbon sink to a carbon source.
"For many thousands of years Alaska has sucked up quite a lot of carbon from the atmosphere and put it into long-term storage as part of the frozen tundra," she says. "The carbon bank has now turned into a carbon exhaust."
Parmesan says the changes are because winters have become warmer and drier, allowing more plants to decompose.
The study came out on the heels of a major global warming report that was released earlier this week.
That report says the rate of warming in the North is rising rapidly.