Reports of new methane-eruption craters in the Siberian permafrost have piqued the interest of scientists around the higher latitudes who see it as a new sign of a warming climate.
The first craters were identified in summer 2014 in the natural gas-rich Yamal Peninsula, which juts into the frigid Kara Sea more than 2,000 miles northeast of Moscow. They're suspected to have been caused by eruptions of methane from beneath the region's permafrost soil, which has been thawing during recent summers.
The English-language news outlet Siberian Times reported this week that scientists have identified numerous other sites, publishing photographs provided by a Russian scientist and local residents. On the other side of the Arctic Circle, University of Alaska geophysicist Vladimir Romanovsky told VICE News that he and some of his colleagues hope to visit the area this summer to investigate them further.
"It's an interesting development, and actually I was expecting to see more of them," said Romanovsky, who is working with several teams of scientists that are looking into the Siberian blowholes, known as funnels.
The region is dotted with small, round lakes that scientists could re-examine "from maybe a different perspective...to see if they are, or originally were, the same features," Romanovsky said.
"If you figure out the process, we can actually better recognize the features that could be — potentially could be — an indication of the development of the same type of phenomenon in Alaska as well," he added.
Most of studies of the region have been conducted by scientists working for the oil and gas industry. The Russian natural gas major Gazprom estimates that trillions of cubic feet of the fuel lie beneath the Yamal Peninsula and the nearby sea floor, and some of the craters are located near a major gas field — meaning a new eruption could pose a hazard to workers or infrastructure, Romanovsky said.
While scientists say the world as a whole has warmed by about 0.8 degrees Celsius (1.4 degrees Fahrenheit) since pre-industrial times, Arctic temperatures are up by more than double that figure. The region's permafrost holds a massive store of carbon frozen within it, largely from methane, which is a far more potent greenhouse gas in the short-term than carbon dioxide. Some scientists have raised concerns that thawing permafrost could release enough methane to speed up climate change.
NASA climate scientist Gavin Schmidt told VICE News that sort of methane feedback loop may be a threat later in the century, but the effects currently "are not at all clear." There's no evidence that a rapid release of methane occurred in previous Arctic warming cycles, the most recent of which happened 8,000 years ago.
But Schmidt said thawing permafrost is causing a host of other issues in the region, including damaged roads, undermined building foundations, and changing the way water forms and drains lakes.
And while the craters are dramatic, Romanovsky said the amount of methane released by their formation is likely small compared to the amount released by the thawing permafrost or what escapes from the gas wells that dot the region.
Romanovsky said he suspects water from melting permafrost is eroding soil underground, similar to the way sinkholes form. The result is a hollow space perhaps 15 to 30 feet underground that fills with gas and erupts when the pressure gets high enough.
"The source of that could be gas hydrates from permafrost. It could also be conventional gas, natural gas, from below permafrost. That has yet to be resolved," he told VICE News. "But I think what's happening is gas pressure and the gas is coming from below the permafrost and from the permafrost itself."
Romanovsky said researchers hope to identify several land features known as hummocks — small hills forced upward by shifts in the permafrost — where gases may be building up underneath and monitor them to see what happens.
Vasily Bogoyavlensky, the Russian scientist who provided photos of the new craters to the Siberian Times, did not respond to requests for comment from VICE News. Bogoyavlensky told the outlet that some of the new funnels were identified from satellite photos, while others were spotted by local residents.
Some of the new sites are on the peninsula, while others were identified in surrounding districts. In one case, people in a town across an inlet from the peninsula spotted a crater after seeing an explosion on the horizon, the Siberian Times reported.
"If it's happening there now, it could start to happen in other places, including Alaska," Romanovsky told VICE News. The permafrost of Alaska and northwestern Canada is generally more stable than in the Yamal Peninsula, but there is "very active warming" in spots on both sides of the border — including around Alaska's Prudhoe Bay, home to a major American oil field.
"It's getting closer to the point where it could actually happen in both places as well," he said.
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