"Of all the global warming gasses, methane is one of the very worst. Pound for pound, the Environmental Protection Agency says its effect on global warming is 20 times greater than that of carbon dioxide. And though its lifetime in the atmosphere is substantially shorter than carbon dioxide, it’s “more efficient at trapping radiation.”
Now scientists have determined that 570 vents, called seeps, are leaking methane gas in the most unlikely of all places: the ocean floor just off the East Coast. The findings, published on Sunday in Nature Geoscience, suggest they’re emitting as much as 90 tons of greenhouse gasses every year and appear to debunk earlier belief that there were only three East Coast seeps beyond the continental shelf.
And if there are more of these seeps — a lot more — it could represent a previously unknown source of damaging carbon emissions."