August 25, 2008 | Discovery ChannelArctic Tundra Holds Global Warming Time BombAug. 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...