permafrost

In what its authors admit is almost certainly an underestimate, a new study says the catastrophic climate changes coming to the Arctic will cost at least $2.4 trillion by mid-century. (To put that into perspective, President Obama just proposed a $3.8 trillion federal government budget for next year.)

The true cost is likely to be a whole lot more -- probably in the range of the combined gross domestic products of Germany, Russia and the United Kingdom, says the report, which was financed by the Pew Environment Group.

A melting Arctic heats the climate in two basic ways: First, when all the white snow and ice on the land and in the ocean melts, the darker colors underneath absorb more heat instead of reflecting it.

The second thing that happens is that as the permafrost melts, it releases methane -- remember methane, that other greenhouse gas, the one we fingered not long ago for its powerful greenhouse punch?

The researchers came up with estimates of how much both of these effects will have and converted those numbers into carbon dioxide equivalents -- i.e., how much of that better-known greenhouse you'd have to release to create this much climate warming.

Those figures are sobering: The amount of warming to be wrought this year alone by Arctic melting will equal about 42 percent of all the emissions from the United States! That's the equivalent of building 500 new coal-burning power plants.

For the second day in a row, we have some really disturbing news coming out of the Far North regarding the pace at which climate change is hurtling forward. (The first was this Western Exposure post.)

Charles J. Hanley of the Associated Press reports that in Canada's Northwest Territories, the permafrost is melting and the Earth is burping out huge slugs of methane, one of the most potent of the greenhouse gases.

This methane has the potential to drive extremely rapid warming. It's known as  a feedback loop: As more methane escapes, it traps more heat in the atmosphere, which in turn melts more permafrost, and so on.

It's not that the earth has never gotten as hot as it apparently is about to get -- there were once balmy beaches and tropical vegetation in Alaska, for instance.

But the pace at which this warming is occurring is giving scientists serious pause, Hanley reports:

Researchers say air temperatures here in northwest Canada, in Siberia and elsewhere in the Arctic have risen more than 4.5 degrees Farenheit since 1970 -- much faster than the global average...

In 2007, air monitors detected a rise in methane concentrations in the atmosphere, apparently from far northern sources.