We're one step closer to finding out why Siberia is riddled with exploding craters

Enormous craters in Siberia's permafrost may finally have a decisive explanation. They form when pressurized water causes cracks to form in the permafrost, triggering a sudden, explosive release of methane gas, scientists say.

The Mysterious craters measure 160 feet (50 meters) deep and up to 230 feet (70 m) across, and first appeared on Russia's northern Yamal and Gydan peninsulas in 2014. Chunks of rock and ice strewn across the landscape around the craters indicated they were caused by giant explosions. These strange craters have never been found elsewhere in the Arctic.

Now, new research may finally explain why these explosions only occur in Siberia.

"These are very, very specific conditions that allow for this phenomenon to happen," study co-author Ana Morgado, a doctoral student and chemical engineer at the University of Cambridge in the U.K., said in a statement. "We're talking about a very niche geological space."

No matter how niche, the explosions could trigger a climate feedback loop leading to huge releases of the powerful greenhouse gas methane.

Related: Thawing Arctic permafrost could release radioactive, cancer-causing radon

"This might be a very infrequently occurring phenomenon," Morgado said. "But the amount of methane that's being released could have quite a big impact on global warming."