Study says methane a new climate threat

By SETH BORENSTEIN, AP Science Writer
Wed Sep 6, 8:06 PM ET

WASHINGTON - Global warming gases trapped in the soil are bubbling out of the thawing permafrost in amounts far higher than previously thought and may trigger what researchers warn is a climate time bomb.

Methane — a greenhouse gas 23 times more powerful than carbon dioxide — is being released from the permafrost at a rate five times faster than thought, according to a study being published Thursday in the journal Nature. The findings are based on new, more accurate measuring techniques.