ceedee’s posterous

“I was in Siberia a few weeks ago, and I am now just back in from the field in Alaska. The permafrost is melting fast all over the Arctic, lakes are forming everywhere and methane is bubbling up out of them.”

“Lakes in Siberia are five times bigger than when I measured them in 2006. It’s unprecedented. This is a global event now, and the inertia for more permafrost melt is increasing.”

This is what University of Alaska ecologist Katey Walter is quoted as saying in a New Scientist article published last week titled Arctic meltdown is a threat to humanity. The article then proceeds to go through the worst-case scenarios that could result from the widespread warming of the Arctic, specifically changes in the thermohaline global ocean current and mass methane releases from permafrost and submarine hydrates.

Simply put, mass releases of methane could, if modelers like David Lawrence of the National Center for Atmospheric Research (NCAR) are right, create heating that feeds on itself (aka “positive feedback”) - warmer Arctic temperatures releases more methane that warms the Arctic further and so on. And if the Arctic changes enough and Greenland melts enough, then the thermohaline current could slow down, resulting in widespread changes ranging from a dramatic reduction in Asian monsoons to a general cooling of Europe. While not mentioned in the New Scientist article, the Carboholic has reported on the possibility of a weaker thermohaline current making oxygen depletion much worse throughout the global ocean, essentially making almost 2/3rds of the ocean unlivable for most existing marine life and 9% of the ocean entirely unlivable for any organism that relies on oxygen.

On potential problem is that the New Scientist article claims that climate models don’t presently include the heat of microbial decomposition of permafrost or the existence of a permanently thawed layer of permafrost that gradually grows due to said decomposition. If this is true, then it could make the real future that much worse than it already is expected to be based on existing models and trends in carbon dioxide emissions, sea level rise, et al.

It certainly doesn’t help that, after a decade of stability, the concentration of methane in the atmosphere started rising again in 2007.

As bad as all that is, there was an interesting aside in the article:

Incidentally, the changing winds might also be to blame for some of the cold and snowy weather in North America and China in recent winters, Overland says. Unusual poleward flows of warm air over Siberia have displaced cold air southwards on either side.

If true, then the unusually cold winter we’ve been having is a direct result of anthropogenic global climate disruption.