Global Warming Puts the Arctic on Thin Ice
A new study of the Arctic permafrost forecasts that global warming will thaw and shrink the total area of perennially frozen ground 60 to 90 percent by 2100.
If true, it will increase the freshwater run-off into the Arctic Ocean by 28 percent, lead to the release by soils of vast doses of greenhouse gases, and upset ecosystems over wide areas.
"This (projection) is definitely higher than other projections, both in area and depth," said David Lawrence, a climate modeler with the National Oceanic and Atmospheric Administration's Climate and Global Dynamics Division.
Lawrence and Andrew Slater of the University of Colorado in Boulder published their permafrost projection in the February issue of Geophysical Research Letters.
Currently in the Northern Hemisphere there are about four million square miles (10 million square kilometers) of land surface that does not thaw, even in the summer, which comes to about 24 percent of the land north of the equator.
Lawrence and Slater incorporated into a computer climate model the current and projected rates of global warming, as well as the physical parameters of freezing and thawing of the upper 11 feet (3.5 meters) of permafrost ground.
They generated a broad-brush image of what might remain of the frozen ground by 2100. That image shows today's permafrost shrinking to between 400,000 and about two million square miles (one to four million square km).
Put another way, the area of permafrost lost by 2100 could match or exceed the total land area of Australia.
Thawing such a vast swath of northern lands means those soils will begin draining, moving more water to the sea, which raises sea levels and could wreak havoc with global weather patterns.
It also means carbon that was frozen in the soils will be free to move up into the atmosphere in the form of the greenhouse gases carbon dioxide and methane, said Lawrence. This whole new source of greenhouse gases isn't something Earth needs right now.
We had better get moving on taking measures to handle this problem before it becomes a runaway train!
Ground Truth Investigations is another great source of information on this topic.
Also check out this National Resource Defense Council article
Check out my previous Global Warming post.