Tuesday, December 13, 2011

Remember that clathrate gun? Huge methane plumes found in the Arctic



In September Steve Bloom gave us a pointer to this:

Something strange



Commercial shipping through the Northeast Passage over the last couple weeks has reported the seas bubbling as if they were boiling.  Their observations have been reported to the science ministry who have sent scientists to investigate.

The story hasn't gone away and hasn't gotten any more reassuring:

Igor Semiletov, of the Far Eastern branch of the Russian Academy of Sciences, said that he has never before witnessed the scale and force of the methane being released from beneath the Arctic seabed.
"Earlier we found torch-like structures like this but they were only tens of metres in diameter. This is the first time that we've found continuous, powerful and impressive seeping structures, more than 1,000 metres in diameter. It's amazing," Dr Semiletov said. "I was most impressed by the sheer scale and high density of the plumes. Over a relatively small area we found more than 100, but over a wider area there should be thousands of them."
 For further context, see here.




See also here:
The East Siberian Arctic Shelf is a methane-rich area that encompasses more than 2 million square kilometers of seafloor in the Arctic Ocean. It is more than three times as large as the nearby Siberian wetlands, which have been considered the primary Northern Hemisphere source of atmospheric methane. Shakhova's research results show that the East Siberian Arctic Shelf is already a significant methane source, releasing 7 teragrams of methane yearly, which is as much as is emitted from the rest of the ocean.
This is one of those things; one of those things that was not supposed to happen. Or not happen for a long time. Or happen very slowly. To have methane boiling out of the Arctic sea, unoxidized, in plumes a kilometer across, in volumes sufficient to raise the local atmospheric levels of methane by a factor of a hundred . . . these are hard and heavy tidings. Hard to know what they mean, exactly, but nothing good.



5 comments:

  1. About five years ago researchers in Greenland said the methane they found trapped in the ice sheet had too low a concentration of deuterium associated with it to have come from the seafloor, and that the clathrate gun hypothesis was dead.

    So who's stupid now, smugsters?

    Damn, we're all gonna die.

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  3. I really wanted to be reassured about methane release, but it seems like it may turn out to be just another change whose speed and force was radically underestimated.

    And behind the methane clathrate is the permafrost, and behind the permafrost are the beetles, the drought and God knows what other threats to the carbon stored in the forests.

    Smart money is still that this won't happen overnight, but build slowly over years and decades. I think what will change shortly is the hopeful prediction that radically cutting emissions will for all intents and purposes stop warming. The ball has rolled too far down the hill for that, I fear. Just to stop pushing it won't accomplish what it would have if we had acted 20 years ago when the threat emerged.

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  4. We are likely heading into a period in which the Arctic Ocean will become ice free, absorb a lot of heat (no melting ice to keep the temperature down) and of hurricanes like the one of Aug6, 2012 which will mix the heat down into deeper water. Note that a counter clockwise storm, causing a counter clockwise current sends water outward by Coriolis and causes upwhelling in the middle of the storm. Zero ice in June or July is a complete game changer with warmer water getting down to the start of the clathrate zone. In addition, if the present density stratification of the Arctic ocean disappears, it only takes mild winds to keep mixing surface warm water down deeper. It sounds crazy but all we can do is to set up a system to ignite all this methane which will be (and already is) being released. The resulting Carbon dioxide is an order of magnitude or two less of a green house gas than methane. With sufficient evolution of methane, the oxygen will be scrubbed out of the ocean and this won't be pretty either.
    http://mtkass.blogspot.co.nz/2008/07/arctic-melting-no-problem.html

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