Siberia's frozen landscape, locked in time for thousands of years, may be coming back to life in violent fashion.

Scientists using both satellite imagery and ground-based surveys have discovered more than 7,000 bulging bubbles of gas on Siberia's Yamal and Gydan peninsulas. These potentially dangerous protrusions contain mostly methane and create a surreal ripple effect on the ground when stepped on. A video taken last summer on Siberia's Bely Island showed first-hand the bizarre nature of this phenomenon.

Because methane is extremely flammable, there is increasing concern that these bulges will begin to explode. One such explosion happened at the end of June on the Yamal Peninsula. Witnesses to the explosion reported fire shooting up in the sky and chunks of permafrost popping up out of the ground. The result was a 164-foot-deep crater on a river near a reindeer encampment (the reindeer are all fled the area, according to The Siberian Times, and a newborn calf was saved by a reindeer herder).

Scientists discovered another crater in June, following reports from locals that an explosion happened sometime between January and April. Aleksandr Sokolov, deputy head of the ecological research and development station of the Institute of Ecology of Plants and Animals, in Labytnangi, told The Siberian Times, "This plot of land was absolutely flat just two years ago," but that by 2016, "it bulged and we could see that soil has [sic] cracked there."

The vast region is already pockmarked with craters from similar explosions, including a 260-foot-wide hole discovered in 2014.

Such hidden dangers in particular pose a threat to both transport infrastructure and Siberia's energy sector.

The dangers of a thawing permafrost

As the emergence of these bulges in a new phenomenon, scientists say they're likely caused by the region's first thaw in more than 11,000 years.

“Their appearance at such high latitudes is most likely linked to thawing permafrost, which in is in turn linked to overall rise of temperature on the north of Eurasia during last several decades,” a spokesperson for the Russian Academy of Science told The Siberian Times in March.

Besides the potential for rapidly forming sinkholes and explosions, these bulges also represent a significant addition to greenhouse gases that contribute to climate change. The release of methane from Siberian permafrost, a gas more than 25 times more potent than carbon in trapping heat in the atmosphere, rose from 3.8 million tons in 2006 to more than 17 million tons in 2013.

The researchers say they will continue to map the gas bubble formations throughout 2017 to determine which pose the most serious danger. With no end in sight, however, for the region's warming trend, it's clear that anyone traveling through Siberia will have to contend with this growing threat for the foreseeable future.