Fifteen mysterious bubbles have been discovered in Siberia. The mysterious bubbles produce a natural waterbed-like reaction when stepped on.

Photo credit: Giphy

Researchers Alexander Sokolov and Dorothee Ehrich, working on the island of Belyy, first spotted a mysterious bubble last year. While the exact reason for these spots hasn't been determined, environmental researchers think they could be linked to the release of methane by melting permafrost under the surface.

When Sokolov and Ehrich punctured one of the spots, air escaped from it. The air contained 200 times more methane and 20 times more carbon dioxide than there is in the air we breathe. Preliminary guesses link the spots with a recent heat wave in Europe.

"It is likely that that 10 days of extraordinary heat could have started some mechanisms, [and the] higher level of permafrost could have thawed and released a huge amount of gases," Sokolov told the Siberian Times.

"It is evident even to amateurs that this is a very serious alarm," he added. "As for the future, we are interested in further study of the bubbles."

Leaking methane from melting permafrost has been linked to sinkholes and craters across Siberia, so Sokolov's current hypothesis could be true. The team will continue to study the strange spots and geologist will monitor the region as well, Science Alert reported.

It is also possible that more bubbles will appear as 2016 is expected to be the hottest year on record, according to a World Meteorological Organization (WMO) report.

The waterbed-like response can be seen in this video created by the Siberian Times: