Predicted methane emission on the East Siberian shelf

Based on the quantitative assessment of present� day methane emission on the East Siberian shelf with presumablly the world’s shallowest gas hydrate depos� its, its predicted growth is expected to follow two pos� sible scenarios: smooth due to the gradual growth of methane diffusion from bottom reservoirs through sedimentary sequences and sharp owing to mass destruction of bottom methane deposits. It is shown that a smooth annual emission growth by 5% should result in a total emission of 50 Gt over 50 years. The sharp growth in methane emission (50 Gt over 1– 5 years) from destructed gas hydrate deposits of the East Siberian shelf should result in an increase in the global surface temperature by 3.3°С by the end of the current century instead of the expected 2°С. Such temperature growth may culminate in catastrophic consequences for the climate system. The East Siberian shelf is characterized by a unique geological history. It represents an element of the Siberian maritime lowland constituting >80% of its area during cold climatic periods and becoming the shallowest and most spacious shelf of the World Ocean