Well, this is troubling.

Global warming is causing the permafrost to melt, which is causing vast amounts of carbon and methane to be released into the atmosphere.

And those gases, of course, are what are causing global warming in the first place.

So it's a feedback loop: The more the world warms, the more the permafrost melts, and the more global-warming gases are released into the atmosphere.

Justin Gillis of the New York Times just went up to Alaska to check this process out firsthand.

Here's what he found:

The "permafrost" zones--the frozen tundra near the Arctic and Antarctic, are basically like millions of square miles of vegetables in the freezer. Frozen, they can stay in their vegetable state forever. The moment they thaw, however, they begin to decompose. And when they decompose, they release carbon and methane into the atmosphere.

A recent estimate put the amount of carbon in just the northern permafrost region at 1.7 trillion tons, which is two and a half times the amount currently in the atmosphere.

Scientists estimate that the carbon released by permafrost thawing could soon equal as much as 35% of the amount of carbon currently released by humans. This, scientists agree, would wildly exacerbate global warming.

So now you have another thing to freak out about.

Read Justin Gillis' thawing-permafrost story here >

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