Vast reserves of methane and carbon dioxide have been found in Arctic permafrost by a team of NASA scientists, a discovery that foreshadows a big uptick in the release of greenhouse gases if the planet's warming continues on its current course.
Rapidly rising temperatures already have had an "amazing and potentially troubling" impact in the Arctic, a group of scientists reported in June after a year-long mission to study how global warming is changing the vast ice- and permafrost-covered region that surrounds the North Pole.
The NASA-sponsored mission, called CARVE -- an acronym for "Carbon in Arctic Reservoirs Vulnerability Experiment" -- uses a specially-outfitted plane that flies low and slow above the pristine wilderness of Alaska's North Slope and the Yukon River Valley, allowing it to measure the interaction ofgreenhouse gases between Earth's surface and the atmosphere.
After its first three flights for 2013 (of a planned seven) concluded in June, the study already had its members re-thinking how quickly the Arctic's permafrost is melting and what that might mean for the carbon stored deep in its frozen soil and sediments.
"Permafrost soils are warming even faster than Arctic air temperatures -- as much as 2.7 to 4.5 degrees Fahrenheit in just the past 30 years," the mission's principal investigator, Charles Miller of NASA's Jet Propulsion Laboratory, said in an interview.
"As heat from Earth's surface penetrates into permafrost, it threatens to mobilize these organic carbon reservoirs and release them into the atmosphere as carbon dioxide and methane, upsetting the Arctic's carbon balance and greatly exacerbating global warming," he added.
What has these scientists alarmed isn't just current levels of carbon dioxide in the atmosphere, whichreached an all-time high of 400 ppm in May, breaking through a threshold long considered the benchmark for "a new danger zone."
Melting permafrost potentially poses a much greater danger because it could release massive amounts of methane into the atmosphere. Methane is much more potent as a heat-trapping greenhouse gas than carbon dioxide, with more than 20 times the global warming potential of CO2 over a 100-year period.................