Michael Reilly, Discovery News
Aug. 25, 2008 -- Locked away in the frozen soils of the Arctic tundra, there lies a ticking time bomb.
Nothing more than accumulated leaves, roots and other plant matter, the unassuming detritus is rich in carbon, giving it the power to dramatically enhance the effects of global warming should it ever get into the atmosphere. But for now it mostly lies dormant, in cold storage in the permafrosts of Siberia, Alaska, and Canada.
That's starting to change, according to some scientists. The planet has already begun to warm as a result of humans pumping billions of tons of carbon into the atmosphere each year. The permafrost is starting to melt, and that pent-up carbon is already leaking into the air in the form of carbon dioxide and methane, powerful greenhouse gases.
Even worse, there may be more of the stuff than anyone ever thought.