Naturally Occurring Methane Vents May Spell Climate Trouble

Only a squawk from a sandhill crane broke the Arctic silence -- and a low gurgle of bubbles, a watery whisper of trouble repeated in countless spots around the polar world. "On a calm day, you can see 20 or more ‘seeps’ out across this lake," said Canadian researcher Rob Bowen, sidling his small rubber boat up beside one of them. A tossed match would have set it ablaze. "It's essentially pure methane." Pure methane, gas bubbling up from underwater vents, escaping into northern skies, adds to the global-warming gases accumulating in the atmosphere. And pure methane escaping in the massive amounts known to be locked in the Arctic permafrost and seabed would spell a climate catastrophe. Is such an unlocking under way?. In 2007, air monitors detected a rise in methane concentrations in the atmosphere, apparently from far northern sources. Russian researchers in Siberia expressed alarm, warning of a potential surge in the powerful greenhouse gas, additional warming of several degrees, and unpredictable consequences for Earth's climate...AP