New study warns of methane escaping from the sea floor due to degradation of submarine permafrost.
Earth is moving as 'leaking methane gas due to global warming causes surface to bubble' in a new phenomenon.
Bulging bumps in the Yamal and Gydan peninsulas believed to be caused by thawing permafrost releasing methane.
Scientists say a 'fountain of gas' poured from jelly-like trembling earth in tundra on Belyy Island in northern Siberia.
Experts to visit remote craters to solve the puzzle on their creation.
Satellites show giant hole ringed by 20 'baby craters'.
Reindeer herders find more craters in the far north in a deepening puzzle for scientists.
Mysterious 'gigantic' hole in remote region spotted by helicopters over gas-rich Yamal peninsula.