A giant crater has appeared in the gas-rich area of Bovanenkovo, Siberia. Authorities are racing to the region to investigate. Courtesy Bulka/YouTube

SIBERIA’S blowholes are exploding in numbers: Up to 20 have now been located, raising new fears the warming permafrost is releasing its deadly methane reserves.

A new report in the Siberian Times has backed up the discovery of four enormous craters in the Siberian tundra last year with news of up to 20 more, smaller vents.

“It is important not to scare people, but this is a very serious problem,” Professor Vasily Bogoyavlensky of theRussian Academy of Sciences says.

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“We must research this phenomenon urgently to prevent possible disasters. We cannot rule out new gas emissions in the Arctic and in some cases they can ignite.”

The new blowholes have been found in the same region, the Yamal Peninsula, which translates to “World’s End”.

It is one of the coldest parts of Siberia. The frozen landscape has trapped methane in the ice-packed earth. This soil has, in recent decades, begun to soften as the climate warms.

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One potential new site is particularly ominous: A 5sq/km lake which is not on older satellite images of the area. Researchers say it may have formed from an eruption of a cluster of blowholes, the largest of which appears to measure some 100m by 50m.

Methane plumes can be seen bubbling up through its waters.

The craters recorded so far have been identified as blow holes instead of sink holes by the raised mound of debris which surround them.

The first was spotted by a helicopter pilot in 2013.

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Expeditions to the bottom of several craters late last year appeared to support speculation that they may have been caused by pockets of defrosted methane gas erupting though the softening surface. Deep lakes of methane-infused “slurry” were found beneath.

Several of the new blowholes were reportedly discovered by reindeer herders.

“I am sure that there are more craters on Yamal, we just need to search for them,” Professor Bogoyavlensky says.

“We need to answer now the basic questions: what areas, and under what conditions, are the most dangerous?”