Saturday, September 13, 2014

The good and bad climate news from permafrost melt

John Upton in Climate Central: Carbon inside now-melting permafrost is oozing out, leaving scientists scrambling to figure out just how much of it is ending up in the atmosphere. Whether recent findings from research that attempted to help answer this question are good or bad climate news might depend on whether you see an Arctic river basin as half full of mud — or half empty.

...Frozen soils known as permafrosts can be found across the planet, and they’re concentrated heavily in the Arctic, which has been warming since the 1980s at twice the global rate. Taken together, permafrosts contain more carbon than is already in the atmosphere. Their warming-induced breakdown is helping to fill the atmosphere with greenhouse gases. In a self-feeding cycle, that's fueling the very climatic changes that are causing permafrost to waste away.

“What everyone’s really concerned about is how all this permafrost carbon is going to decompose,” said aquatic geochemist Rose Cory, an assistant professor at the University of Michigan. “If all of that gets turned into carbon dioxide, then we’ll more than double the amount of carbon dioxide in the atmosphere.”

A team of U.S. scientists led by Cory studied Arctic waterways and found that nearly half of the carbon that’s eroding from melting Arctic permafrost is flowing through rivers and lakes and ending up in the seas. Eventually, that sea-bound carbon is likely to be gobbled into aquatic food chains or to settle on ocean floors. The rest is being oxidized in waterways into carbon dioxide, floating into the skies instead of out to sea....

Polar photo ace Brocken Inaglory shot this great image of patterns in permafrost, Wikimedia Commons, under the Creative Commons 3.0 license

No comments: