Crenarchaeotal membrane lipids in lake sediments: A new paleotemperature proxy for continental paleoclimate reconstruction?
- Lindsay A. Powers1,
- Josef P. Werne1,
- Thomas C. Johnson1,
- Ellen C. Hopmans2,
- Jaap S. Sinninghe Damsté*2 and
- Stefan Schouten*2
- 1Large Lakes Observatory, University of Minnesota Duluth, 10 University Drive, Duluth, Minnesota 55812, USA
- 2Netherlands Institute for Sea Research, Department of Marine Biogeochemistry and Toxicology, P.O. Box 59, 1790 AB Den Burg, Netherlands
Abstract
Paleoclimate studies of continental environments have been hampered by the lack of an independent paleotemperature proxy. A novel sea-surface temperature proxy has been proposed for marine systems based on membrane lipids of marine crenarchaeota (the TEX86—tetraether index of tetraethers with 86 carbon atoms). Analysis of archaeal membrane lipids in core-top sediments from a diverse suite of lacustrine systems suggests the ubiquitous occurrence of low-temperature crenarchaeota in lake systems as well. Application of the TEX86 proxy in these lacustrine systems indicates that it is valid in lake environments, and the calibration of TEX86 in lacustrine systems is similar to that in the marine environment. This proxy will provide an independent continental paleotemperature tool that will allow paleoclimatologists to address fundamental questions about temperature variability in continental environments and its relationship to climate change.
Footnotes
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↵*Also at Faculty of Geosciences, Utrecht University, P.O. Box 80.021, Utrecht, Netherlands
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- Accepted March 11, 2004.
- Received December 19, 2003.
- Revision received March 10, 2004.
- Geological Society of America
