What’s so bad about a little feedback?

The worst-case, runaway greenhouse effect scenario involves a concept known as “positive feedback,” wherein changes in climate cause environmental changes that then, in turn, cause more and more rapid climate change, so the whole thing basically becomes a runaway train and there’s little to nothing that humanity can do about it. Loss of plants, via deforestation or desertification, is a big positive feedback, because it means fewer plants absorbing less carbon dioxide, which means more and faster warming, which means further loss of forests and green areas, lather, rinse, repeat. Another might be an increase ocean temperatures, which reduces the amount of CO2 that can be absorbed by ocean waters, which means more and faster warming, which means further increases in ocean temperatures, and so on.

Two of the most worrisome potential sources of positive feedback are in the Arctic. One is the potential for melting permafrost to release significant quantities of methane, which is buried underground by the decomposition of plant matter and then effectively capped off by the frozen ground above it. As that ground melts, the methane could be released. The other concern is that large fields of methane ice, frozen mostly at the bottom of the heretofore very cold Arctic Ocean, could melt as water temperatures rise, which would send methane bubbling to the surface, and from there on into the atmosphere. As far as I can tell, and I’m not a climate scientist, once this kind of thing starts happening, nobody really has a good sense of what comes next. A whole bunch of methane could be released really quickly, in which case we could see relatively sudden climate impacts, or it could trickle out more slowly, in which case the climate impacts will also be felt more slowly but it will be that much harder to try to get carbon emissions back to a sustainable level. Either way, this means more atmospheric carbon, which is bad news.

So, um, here’s the thing (via):

By now, you’ve heard of the crater on the Yamal Peninsula. It’s the one that suddenly appeared, yawning nearly 200 feet in diameter, and made several rounds in the global viral media machine. The adjectives most often used to describe it: giant, mysterious, curious. Scientists were subsequently “baffled.” Locals were “mystified.” There were whispers that aliens were responsible. Nearby residents peddled theories of “bright flashes” and “celestial bodies.”

There’s now a substantiated theory about what created the crater. And the news isn’t so good.

It may be methane gas, released by the thawing of frozen ground. According to a recent Nature article, “air near the bottom of the crater contained unusually high concentrations of methane — up to 9.6% — in tests conducted at the site on 16 July, says Andrei Plekhanov, an archaeologist at the Scientific Centre of Arctic Studies in Salekhard, Russia. Plekhanov, who led an expedition to the crater, says that air normally contains just 0.000179% methane.”

The scientist said the methane release may be related to Yamal’s unusually hot summers in 2012 and 2013, which were warmer by an average of 5 degrees Celsius. “As temperatures rose, the researchers suggest, permafrost thawed and collapsed, releasing methane that had been trapped in the icy ground,” the report stated.

crater possibly created by escaping methane (Salon)

and here’s the other thing (via):

Vast methane plumes have been discovered boiling up from the seafloor of the Arctic ocean on the continental slope of the Laptev Sea by a dream team of international scientists. Over the last decade a warming tongue of Atlantic ocean water has been flowing along the Siberian Arctic ocean’s continental slope destabilizing methane ice, hypothesize the team of Swedish, Russian and American scientists. The research team will take a series of measurements across the Siberian seas to attempt to understand and quantify the methane release and predict the effect of this powerful greenhouse gas on global and Arctic warming.

Methane bubbling to the surface in a lake in Alaska (NY Times)

Luckily the American political machine, always reliable for its quick action and keen foresight, is taking action…by suing the EPA for trying to regulate coal emissions, and (potentially) by putting Delaware’s taxpayers on the hook for saving an oil refinery from sea level rise. This is all brought to you by our good friends in the fossil fuel industry, who are happy to cause global warming, but please don’t expect them to bear any of its costs.

Author: DWD

writer, blogger, lover, fighter

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