Dynamics of Gas Hydrates and Permafrost in the Eurasian and North American Arctic Land-Shelf System

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AbstractOPP-998586OsterkampMethane hydrates occur when methane and water exist in close proximity at low temperatures and elevated pressures. These conditions are present in permafrost regions and beneath the sea along the outer continental margins. Consequently, methane hydrates are thought to be widespread in the onshore permafrost regions of the North American and the Russian Arctic and in the shallow continental shelves of the Arctic Ocean where subsea permafrost is found. These gas hydrates are a potential and abundant source of energy, a major sink for global carbon, and could influence seafloor stability.Low sea levels 20,000 years ago exposed the shallow continental shelves of the Arctic Ocean to the cold climate, allowing permafrost and stable gas hydrates to form in these shelves. Climatic warming and changes in sea level warm the permafrost and destabilize the hydrates. Methane gas is produced during hydrate destabilization and may eventually be released to the atmosphere. Permafrost temperatures are known to have increased 2-4oC during this century and current climatic models predict continued warming. With present knowledge, it is not possible to predict the amount or timing of methane releases by gas hydrate decomposition as a result of permafrost, especially subsea permafrost, degradation.The Principal Investigators will survey existing data on gas hydrate and permafrost conditions in the Russian Arctic land-shelf system to establish boundary conditions, properties, occurrence and distribution. This information will be used as in the future as input data for a two dimensional numerical model of gas hydrates and permafrost. A model was developed by the Principal Investigators in the late 1980s and modified in the early 1990s specifically for studies of permafrost, subsea permafrost and gas hydrates over long time scales. The Principal Investigators will collect and synthesize existing data on the occurrence of gas hydrate in permafrost on the Russian Arctic land-sea margin. The data will be evaluated for reliability, standardized, and translated into English. This project will address the synergism between gas hydrates, climate and sea level and help to increase our understanding of how gas hydrates destabilize over geological time scales. The research will be conducted jointly by the Geophysical Institute and Russian investigators.