Arctic lakes producing methane could have been responsible for 87 percent of the methane spike in the last ice age, said UAF researcher Katey Walter, lead author of a report printed in the October 26^th issue of Science.

“It tells us that this isn’t just something that is ongoing now. It would have been a positive feedback to climate warming then, as it is today,” said Walter. “We estimate that as much as 10 times the amount of methane that is currently in the atmosphere will come out of these lakes as permafrost thaws in the future. The timing of this emission is uncertain, but likely we are talking about a time frame of hundreds to thousands of years, if climate warming continues as projected.”

Most of the areas Walter examined in Siberia and Alaska were dry grasslands covering permafrost during the last ice age.

“Methane release has been known for a number of years now,” said geologist Dr Lorenz Schwark at the University of Cologne in Germany. “There are various areas around the world that have been studied in detail.”

He said the process of methane release from hydrates had been filmed by robotic vehicles off the coast of Vancouver Island in Canada, for example.

“The problem is that in the Russian or in the Siberian Arctic on land and in the sea there is very little coverage by hard data and there are hardly any measurements. And therefore there is a lot of speculation going on.”

That’s not the way Katey Walter sees it though, “It happened on a large scale in the past, and it could happen on a large scale in the future,” said Walter, who calls potential methane emissions “a time bomb.”