Digging up the dirt on Arctic carbon(Read article summary)
The concern: As the Arctic continues to warm and the permafrost begins to thaw, significant amounts of carbon will find their way into the atmosphere.
You never know what you'll find until you dig a little deeper. Scientists taking the measure of how much carbon the Arctic locks up beneath its tundra have done just that. Based on what they've found, they estimate that the Arctic could harbor an average of 60 percent more carbon that previous estimates have indicated.
Researchers are interested in the Arctic's carbon budget because projections of global warming suggest that the region's average temperature could warm by as much as 6 degrees Celsius (10.8 degrees Fahrenheit) by the end of the century, depending on the trajectory that emissions from human activities take. The concern: As the Arctic continues to warm and the permafrost thaws, significant amounts of carbon will find their way into the atmosphere as carbon dioxide or methane. These added greenhouse gases would serve to reinforce global warming.
The results come from a group led by University of Alaska at Fairbanks soil scientist Chien-lu Ping and published in today's edition of Nature Geoscience. Hints that the Arctic's tundra may lock up more carbon than older, widely cited estimates had indicated date back at least to 2005. For instance, a team led by Jeffery Welker at the University of Alaska at Anchorage reported at a meeting of the American Geophysical Union that in Greenland, it was finding between nine and 125 times the amount of carbon previously reported, depending on the type of Arctic landscape yielding the measurements.