Gaea to Man: Pull My Finger!

‘Widespread methane leakage’ coming from hundreds of vents off East Coast ocean floor

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.”

I've seen the number quoted as anywhere from 20 to 300, but the trend seems to be downward. The reason it's supposed to be 20 times worse is because it absorbs radiation more efficiently. Redundancy for the sake of alarm, or merely the reporters ignorance? I'll let you decide.

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.

So surely, if this is a great threat to global climate it's caused by man, right?

. . . the seeps aren’t fresh ones. “The fact that it’s there in the quantities that it is — and [that] it is exposed — suggests that indeed the processes at these locations have been going on … at least 1,000 years,” Skarke told NBC News. He said he didn’t visit all the seeps, with the most concentrated clusters apparently located off the Chesapeake Bay, but “the ones we visited suggest a very prolonged seepage.”

1000 years?  I guess we can blame the carbon policies of Æthelred the Unready.

How widespread are the seeps?

The finding raises a number of questions. First on the list: Are there a lot more? The paper says the discovery suggests “tens of thousands” of similar vents could pockmark the ocean floor, emitting vast quantities of methane gas. He told the BBC that their number could be as high as 30,000.

Gaea ate a mighty big burrito. But the good news is, it's probably not going to affect the climate after all (any more than it has the last 1000 years):

There is one bit of good news: The depth of the East Coast seeps are so deep that the methane gas isn’t likely reaching the atmosphere. “The methane is dissolving into the ocean at depths of hundreds of meters and being oxidized into” carbon dioxide, Skarke told the BBC. “But it is important to say we simply don’t have any evidence in this paper to suggest that any carbon coming from these seeps is entering the atmosphere.”

Methane, whether from deep oceans seeps or fracking, simply doesn't make it anywhere near to the list of things that keep me awake at night. While, molecule for molecule, methane may be a much more powerful green house gas than CO2, it's concentration (approximately 1900 ppb) is so much lower than CO2s (~400 ppm) that it amounts to a small fraction of any greenhouse warming. Furthermore, it doesn't appear to rising anywhere near as fast as CO2.

Finally, and this can't be said often enough or loud enough, the world hasn't warmed in the last 17, approaching 18 years, according to the satellite data.