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The large amount of methane is withdrawn from turnover of the Earth and preserved in permafrost. Methane is emitted in the atmosphere during the permafrost degradation on the shelf, the continent and the melting of the subsurface ice. In recent decades great attention is given to analysis of the methane content inasmuch as, according to the relevance, methane is the second greenhouse gas after the carbon dioxide, its increase in the atmosphere has a significant impact on the climate as a whole. Since the second half of the XX century, the concentration of methane in the atmosphere has been increasing annually by 1%. The data about the concentration of methane contained in the air bubbles of the subsurface ice and frozen rocks of the cliff near the polar station Marre-Sale were obtained. Abnormally high value of the concentration of methane in the air bubbles is set in the massive ground ice. The methane content reaches 21.5 ml/kg; it exceeds the amount of methane in the permafrost sediments and in the ice wedges. The monitoring observation of 4 kilometers of retreat of the sea shore has showed that the shore recedes at an average rate of 1.7 meters a year. The methane concentration was measured by use of gas chromatography HPM4 (Russia) with flame-ionization analyzer IFHBP RAS (Pushchino) in the 101st gas sample of sediments and ice by Headspace method. It was rated that annually 10.3 kg or 14.3 cu m of methane is emitted in the atmosphere because of the destruction of 100 meters of seashore. 463.5 kg or 643.5 cu m of methane were emission as a result retreat of 4.5 km of seashore. The total amount of methane coming from 100 square meters of shore segment for the year is up to 0.501 kg (CH4) year. According to Kazantsev V.S. (2013) 0.117 kg (CH4) in a year is emitted in terms of 100 square meters of fenland march ecosystem. Methane emissions from the retreating sea costs with underground ice are large and comparable to the emission of methane to the surface of the wetland ecosystems that need to be considered in climate models predicted.