Scientist are
increasingly concerned about the levels of methane gas escaping to the atmosphere from melting Arctic permafrost. Methane is 33 times more potent greenhouse gas than carbon dioxide. In July a helicopter pilot working for the gas industry spotted a large crater in the Yamal Pennisula 50 meters wide that seemed bottomless. Speculation immediately erupted about what could have caused such an unusually large sinkhole ranging from a meteor impact to extraterrestrial activity. Scientists journeyed to the remote location and found very high concentrations of methane at the bottom of the crater (9.6%). The investigators now think the crater is linked to the unusually warm summers of 2012 and 2013 that melted permafrost that collapsed the icy overlay and allowed methane to escape. Over the last twenty years permafrost up to a depth of 20 meters has warmed about 2℃. Researchers lead by Florida State University
found that permafrost melting is accelerating decomposition of plantsthat is also releasing more carbon to the atmosphere. If all the world's permafrost melts
as global temperatures climb, there would be five times the amount of carbon in the atmosphere than there is now.
Methane gas pressure was apparently high enough at the Yamal site to push overlaying soils away, forming the crater. Methane hydrates, in which methane is trapped in ice, occur in Arctic soils usually at a depth of 100 meters. The depth of the Yamal crater is estimated to exceed 70 meters at which depth a pool of water was viewed by a video camera lowered on a fifty meter rope. Since the discovery local herders have found similar but smaller holes in the vicinity. If a methane blow-out is responsible for the crater it could pose a safety issue to a natural gas plant 30kms away as well as villages in the area. Researchers have suggested releasing built up gas pressure by drilling holes into the permafrost, as difficult task given the remote location and danger. The crater's rim is meting and unstable, falling into the cavity
