Graphic by Annabel Driussi for ODP

by Amy Lupica, ODP Staff Writer

A new study may reveal the mystery behind violently exploding craters in the Siberian tundra. Last year, a 17th massive permafrost crater cracked open in the Russian arctic; the first was spotted in 2013, leaving scientists searching for a reason as to why it had appeared. 

The craters, the most recent 100 feet deep and 20 meters wide, were theorized to be caused by a meteor impact, UFOs, or secret military trainings, but now scientists think it’s most likely the usual suspect: climate change. 

• More specifically, thawing permafrost allows for the accumulation of methane below ground that eventually causes an explosion. 

But thawing permafrost in the Arctic has more consequences than a few big holes.

Why This Matters: Permafrost, land near the poles that is supposed to stay frozen year-round, is thawing at alarming rates. Nine million square miles of land and about 25% of the northern hemisphere is permafrost, a total land area of more than the U.S., Canada, and China combined. The Arctic is warming twice as fast as any other region in the world, and even though permafrost can extend miles underground, it’s already begun a massive retreat. According to the National Snow and Ice Data Center, permafrost has retreated by 10% in just the last century. Arctic permafrost sequesters vast reserves of carbon dioxide and methane and is estimated to contain twice the amount of carbon already in the atmosphere. If it continues melting, it will release those greenhouse gasses, wreaking untold havoc on our atmosphere.

The Causes:

Scientists believe that the massive craters in the Russian Arctic were caused by melting permafrost releasing methane.

• Cave-like formations in the craters’ base told researchers that methane gas had expanded, creating pockets in the ground that caused the surface to swell.
• After enough buildup, the pocket would burst, throwing rock, ice, and debris into the air. 

 Researchers know that the methane must come from thawing permafrost, but they’re not sure how deep the thawing extends. The escaping methane may come from shallow permafrost, but if it comes from permafrost miles underground, it would mean Arctic thawing has progressed much further than previously thought.

Researchers also say that predicting these craters is incredibly difficult, although they have some ideas about when they’re most likely to occur. Using satellite imagery, they determined that the latest crater exploded between May 15 and June 9, 2020, although it was not found until July 16 of that year.

Evgeny Chuvilin, the lead research scientist at the Skolkovo Institute of Science and Technology’s Center for Hydrocarbon Recovery in Moscow, explained, “this is the time of the year when there’s a lot of solar energy influx, which causes the snow to melt and the upper layers of the ground to heat up, and that causes changes in their properties and behavior.”

He warned that as climate change warms the region, these crater explosions could become increasingly likely not just in the summer but year-round. 

Scientists at Woodwell Climate Research Center in Massachusetts have created an algorithm that measures the height of mounds and hills using satellite imagery to best guess where another methane pocket may be occurring, and they’ve had some success. Their model predicted seven reported craters and three developing ones. Sue Natali, Arctic program director at the Woodwell Climate Research Center, says that this phenomenon is a new frontier even with her team’s successes. “These craters represent a … process that was previously unknown to scientists,” she said. “The craters and other abrupt changes occurring across the Arctic landscape are indicative of a rapidly warming and thawing Arctic, which can have severe consequences for Arctic residents and globally.”