11,000 years ago it is believed methane was a major factor in a period of global warming. Methane levels in our atmosphere have tripled since pre-industrial times. Much of that increase (70 %) can be traced to rice cultivation, cattle raising, coal mining and other human activities. Mother Nature takes the lead on the other 30 percent.
At the end of the 20th century the 51 million metric ton methane emission rate came from the north; 64 per cent from Russia, 11 per cent from Canada, and 7 per cent from Alaska.
Walter’s work “has gotten a lot of attention,” said John E. Walsh, chief scientist of the International Arctic Research Center in Fairbanks. “She found direct evidence of methane releases in high-latitude lakes. That was not fully realized before.”
For the last half century the Arctic Circle is warming twice the rate of the rest of the world. Polar bears and emperor penguins may be lost due to that increase. While the glaciers and sea ice have been the focus of news headlines the growing concern now is the transformation of permafrost.
By the end of the century the 20% of the Earth’s surface that is frozen may have thawed out. Air temperatures in the Arctic Circle are expected to rise as much as 6 degrees Celsius. When that happens the emission of carbon compounds will hit the atmosphere at an alarming rate.
The upper 3 meters of permafrost holds 1.9 trillion tons of carbon. That is more than double what is in the atmosphere today.
The LA Times reports:
“We are seeing thawing down to 5 meters,” says geophysicist Vladimir Romanovsky of the University of Alaska. “A third to a half of permafrost is already within a degree to a degree and a half [Celsius] of thawing.”
If only 1% of permafrost carbon were to be released each year, that could double the globe’s annual carbon emissions, Romanovsky notes. “We are at a tipping point for positive feedback,” he warns, referring to a process in which warming spurs emissions, which in turn generate more heat, in an uncontrollable cycle.
For the next two years the researchers funded by the National Science Foundation and NASA, will move between Siberia and Alaska. They will drill, analyze and try to determine how the methane from these Arctic lakes will change the future climate of the Earth.
“By figuring out how quickly permafrost thawed in the past, we can test our models to predict how fast it could thaw in the next 100 years,” says Lawrence Plug, a geophysicist from Dalhousie University in Halifax, Canada; Guido Grosse, a German geologist, who will make the complex calculations. “If the temperature warms a couple of degrees Celsius, the lakes could expand at two or three times their current rate.”