https://phys.org/news/2021-03-east-siberian-arctic-ocean-elevated.html
Researchers have found that such releases can sometimes result in pressure building up as the gas makes its way into unstable parts of the ocean floor. And that can lead to seepage or sometimes explosive events as the gas is suddenly released up through the water and to the surface.
Planet scientists are concerned that warming waters, in addition to a warming atmosphere, could accelerate the release of methane into the air, resulting in accelerating warming, which could in turn lead to accelerated permafrost melting. This cycle could lead to warming the entire planet at a faster pace than has been predicted.
Despite the attempt to dismiss this science as "doom" propaganda or fear-mongering - the evidence continues to corroborate the original claim of Dr. Natalia Shakhova.
The work involved first obtaining water samples from regions of the East Siberian Arctic Ocean. Each of the samples then underwent triple-isotope-based fingerprinting. Doing so showed that only a small amount of the methane was coming from shallow microbial sources—the rest was coming from what the team believes is a very large, deep thermogenic reservoir. The researchers also believe the reservoir is located beneath the Laptev Sea; a portion of the East Siberian Arctic Ocean situated north of the eastern part of Russia.
https://www.pnas.org/content/118/10/e2019672118
Taken together, the triple-isotope data presented here, in combination with other system data and indications from earlier studies, suggest that deep thermogenic reservoirs are key sources of the elevated methane concentrations in the outer Laptev Sea. This finding is essential in several ways: The occurrence of elevated levels of radiocarbon-depleted methane in the water column may be an indication of thawing subsea permafrost in the study area (see also ref. 8). The triple-isotope fingerprinting suggests, however, that methane may not primarily originate directly from the subsea permafrost; the continuous leakage of an old geological reservoir to the water column suggests the existence of perforations in the subsea permafrost, serving as conduits of deeper methane to gas-charged shallow sediments. Second, the finding that methane is released from a large pool of preformed methane, as opposed to methane from slow decomposition of thawing subsea permafrost organic matter, suggests that these releases may be more eruptive in nature, which provides a larger potential for abrupt future releases."
ERUPTIVE In NATURE. Not only is that a great band name but it's "methane bomb" as a synonym.
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