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Abstracts
SEARCH Open Science Meeting
October 27, 2003
Seattle, Washington, USA
In Search of the Younger Dryas at Elikchan Lake, Northeast Siberia
Heather D. Heuser1, Patricia M. Anderson2, Linda B. Brubaker3, Ron S. Sletten4, Thomas A. Brown5, Anatoly V. Lozhkin6
1College of Forest Resources/Quaternary Research Center, University of Washington, 19 Johnson Hall, Box 351360, Seattle, WA, 98195, USA, Phone 206-543-5777, Fax 206-543-3836, hdheuser@u.washington.edu
2Earth and Space Sciences/Quaternary Research Center, University of Washington, 19 Johnson Hall, Box 351360, Seattle, WA, 98195, USA, Phone 206-543-1166, Fax 206-543-3836, pata@u.washington.edu
3College of Forest Resources, University of Washington, Box 352100, Seattle, WA, 98195, USA, Phone 206-543-5778, lbru@u.washington.edu
4Earth and Space Sciences/Quaternary Research Center, University of Washington, 19 Johnson Hall, Box 351360, Seattle, WA, 98195, USA, Phone 206-543-1166, Fax 206-543-3836, sletten@u.washington.edu
5Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA, 94550, USA, Phone 925-423-8507, Fax 925-423-7884, tabrown@llnl.gov
6North East Interdisciplinary Research Institute, Far East Branch, Russian Academy of Sciences, 16 Portovaya Street, Magadan, 685000, Phone 413-223-0051, lozhkin@neisri.magadan.ru
The Younger Dryas (YD) was a late Pleistocene climatic oscillation that occurred approximately 11,000-10,000 14C yr B.P. (13,000-11,500 cal yr BP), after a millennium of post-glacial climate amelioration. Characterized by dramatic and abrupt climatic cooling over much of the world, the YD has generated a great deal of scientific interest, particularly due to its extremely rapid termination. The global distribution of the YD signal has been the focus of much attention, as an understanding of global geographic extent is essential for determining the mechanisms and causes of paleoclimatic change. Such an understanding is extremely valuable in the face of future climate change, as climatic patterns and ecosystem responses seen in the past can help predict how different components of the climate system might react in the future.
Although the YD has been referred to as a global event, analysis of paleo-data indicates that not all high latitudes experienced a climatic response to the YD. In Beringia, the area encompassing northeast Siberia, Alaska, and northwest Canada, the YD signal is complex. Far western Beringia and southern areas of eastern Beringia appear to register dramatic cooling during the YD; northern and interior areas of eastern Beringia register a mixed signal; and most of western Beringia shows uninterrupted warming into the Holocene, with the exception of Wrangel Island where it appears to have been warmer and wetter than present during the YD. Importantly, however, many of the studies conducted in western Beringia were not of high enough resolution to have recorded the brief and abrupt climatic event of the YD, or they did not have well-constrained dating control. To address this issue, this study uses a multi-proxy, high resolution analysis to identify any YD signal in a sediment core taken from Elikchan Lake, northeast Siberia. The sediment core was analyzed for sediment magnetic susceptibility, grain size, fossil pollen assemblage, organic carbon content, and biogenic silica content at approximately 100 year intervals. Interestingly, the data show a strong signal marking the glacial to interglacial transition but they do not reflect any abrupt changes that would be expected for a YD event.
Abstract Categories: Changes on Land, Student Poster
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