- Jan 12, 2005
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Those mysterious Siberian craters? Looks like they're the result of large pockets of methane gas pushing their way through permafrost thawed and melted by increasing temperatures. These are the first such events that climatologists are aware of, and is quite worrisome, because methane is a much more efficient greenhouse than CO2. This could lead to a runaway cycle of methane release - the so-called "clathrate gun" hypothesis. But maybe it's not as bad as we climate-change worriers think:
http://en.wikipedia.org/wiki/Clathrate_gun_hypothesis
So why worry? Probably, this methane release isn't going to wipe out humanity during the next hundred years or so. Probably, mass extinctions are still several thousand years away. We can all still fiddle while the permafrost burns.
http://www.washingtonpost.com/news/...rater-mystery-and-the-news-isnt-good/?hpid=z1
http://en.wikipedia.org/wiki/Clathrate_gun_hypothesis
However, there is stronger evidence that runaway methane clathrate breakdown may have caused drastic alteration of the ocean environment (such as ocean acidification and ocean stratification) and the atmosphere of earth on a number of occasions in the past, over timescales of tens of thousands of years; these events include the PaleoceneEocene Thermal Maximum 56 million years ago, and most notably the PermianTriassic extinction event, when up to 96% of all marine species became extinct, 252 million years ago.
So why worry? Probably, this methane release isn't going to wipe out humanity during the next hundred years or so. Probably, mass extinctions are still several thousand years away. We can all still fiddle while the permafrost burns.
http://www.washingtonpost.com/news/...rater-mystery-and-the-news-isnt-good/?hpid=z1
Researchers have long contended that the epicenter of global warming is also farthest from the reach of humanity. Its in the barren landscapes of the frozen North, where red-cheeked children wear fur, the sun barely rises in the winter and temperatures can plunge to 122 degrees below zero. Such a place is the Yamal Peninsula in Siberia, translated as the ends of the Earth, a desolate spit of land where a group called the Nenets live.
By now, youve heard of the crater on the Yamal Peninsula. Its 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.
Theres now a substantiated theory about what created the crater. And the news isnt 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 Yamals 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.
Plekhanov explained to Nature that the conclusion is preliminary. He would like to study how much methane is contained in the air trapped inside the craters walls. Such a task, however, could be difficult. Its rims are slowly melting and falling into the crater, the researcher told the science publication. You can hear the ground falling, you can hear the water running; its rather spooky.
Gas pressure increased until it was high enough to push away the overlaying layers in a powerful injection, forming the crater, explained geochemist Hans-Wolfgang Hubberten of Germanys Alfred Wegener Institute, adding that hes never seen anything like the crater.
Some scientists contend the thawing of such terrain, rife with centuries of carbon, would release incredible amounts of methane gas and affect global temperatures. Pound for pound, the comparative impact of [methane gas] on climate change is over 20 times greater than [carbon dioxide] over a 100-year period, reported the Environmental Protection Agency.
As the Associated Press put it in 2010, the melting of Siberias permafrost is a climate time bomb waiting to explode if released into the atmosphere.
Researchers with Stockholm Universitys Department of Applied Environmental Science recently witnessed methane releases in the East Siberian Arctic Ocean. They found that elevated methane levels [were] about ten times higher than in background seawater, wrote scientist Orjan Gustafsson on his blog last week. He added: This was somewhat of a surprise This is information that is crucial if we are to be able to provide scientific estimations of how these methane releases may develop in the future.
NASA also found the situation to be precarious. The fragile and rapidly changing Arctic region is home to large reservoirs of methane, a potent greenhouse gas, scientists wrote in 2012. Its vulnerable to being released into the atmosphere, where it can add to global warming.
Now, as two additional craters have also recently been discovered in Siberia, researchers worry the craters may portend changes to local Siberian life. Two have appeared close to a large gas field. If [a release] happens at the Bovanenkovskoye gas field that is only 30 kilometers away, it could lead to an accident, and the same if it happens in a village, Russian scientist Plekhanov told Nature.
