Methane hydrates and climate change the clathrate gun hypothesis
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April 8, 2004 Methane hydrates and climate change: the clathrate gun hypothesis SPEAKER Richard J. Behl AAPG Distinguished Lecturer CO-AUTHORS Kevin G. Cannariato University of Southern California Ingrid L. Hendy University of Michigan James P. Kennett University of California, Santa Barbara What caused repeated, remarkably rapid, global warming events that occurred in less than one human lifespan during the late Quaternary? A likely, but controversial, culprit is methane hydrate (or clathrate), which makes up a vast reservoir of frozen methane in ocean sediments. Destabilization of the reservoir through changes in sea-floor temperature and pressure may release methane (a powerful greenhouse gas) into the ocean and atmosphere, with dramatic climatic consequences. The Clathrate Gun Hypothesis proposes that the marine methane hydrate reservoir was repeatedly reloaded and discharged as clathrates accumulated during cold glacial intervals only to be dissociated when triggered by pulses of warmer intermediate water impinging on the continental slopes. This mechanism could have greatly amplified and accelerated global warming episodes. Could methane hydrates play a role in present and future climatic change,as well? This presentation explores whether the present is always the best key to the past, or whether these dramatic episodes in Earth's history were unique in their sensitivity to certain triggers of climatic and environmental change. BIOGRAPHY Richard J. Behl graduated in 1978 with his B.A. in Chemistry with Earth Sciences Specialization from the University of California, he then went on to receive his Ph.D. in Earth Sciences from the University of California at Santa Cruz in 1992. Between 1978 and 1987 Richard worked as a wellsite geologist for a number of companies. From 1992 to 1995 Richard was a Postdoctoral Fellow at the University of California. From 1995 to1999 Richard was an Assistant Professor at California State University. Presently Richard is an Associate Professor at California State University. Richard has authored and co-authored 29 professional papers, 54 abstracts, and 1 book on marine sedimentology and stratigraphy, diagenesis of silica- and organic carbon-rich sediments, and paleoceanography. Richard has special interests in the sedimentary record and diagenesis of the Neogene through Quaternary of the California Margin. Richard is involved with AAPG, American Geophysical Union, GSA, International Association of Sedimentologists, and the Society for Sedimentary Geology.