Scientists believe the giant holes in north Siberia were originally a phenomenon known as a pingo.
This is a subsurface accumulation of ice that has been covered by land.
Pingos are dome-shaped mounds over a core of ice.
At least ten are known to have exploded in Siberia in recent years forming craters.
The craters were only first discovered in 2014 and were shrouded in mystery.
When this happens it can leave behind a gaping hole.
The melting of the permafrost caused natural gas trapped in the soil to be released and accumulate in the void, causing the pressure to build and eventually erupt from the ground.
Rising temperatures in the soil would have increased the pressure, leading to an eruption.
Initially there was mystery over the sudden formation of the dramatic craters – first noticed in 2014 – with claims they could have been formed by missile tests from Vladimir Putin’s military machine, or even by aliens
There has been significant activity in the region, with reports of underground methane bubbles about to explode in the region.
Bulging bumps filled with methane in the Yamal and Gydan peninsulas are believed to be caused by thawing permafrost.
Yamal is Russia’s main area for extracting natural gas, and there are fears that explosions could lead to damage to key energy facilities.
When the bubbles explode they release methane gas which is approximately 84 times more potent than carbon dioxide.
After they’ve exploded they leave gigantic funnels or craters.
The extent of the harmful greenhouse gases buried in this new phenomenon of jelly-like bubbles poses ‘very serious alarm’ concerning the impact of global warming, experts have warned.
Russia set up an early warning system of seismic sensors hoping to predict when these explosions would occur.