Role of methane clathrates in past and future climates

  title={Role of methane clathrates in past and future climates},
  author={Gordon J. MacDonald},
  journal={Climatic Change},
  • G. MacDonald
  • Published 1 June 1990
  • Environmental Science, Geology
  • Climatic Change
Methane clathrates are stable at depths greater than about 200 m in permafrost regions and in ocean sediments at water depths greater than about 250 m, provided bottom waters are sufficiently cold. The thickness of the clathrate stability zone depends on surface temperature and geothermal gradient. Average stability zone thickness is about 400 m in cold regions where average surface temperatures are below freezing, 500 m in ocean sediments, and up to 1,500 m in regions of very cold surface… 
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