HR: 08:00h
AN: PP41B-01 INVITED     [Abstracts]
TI: Climatic Calibration of Paleoecological Data and Data/Model Comparisons
AU: * Webb, T
EM: thompson_webb_iii@brown.edu
AF: Brown University, Department of Geological Sciences, Providence, RI 02912-1846 United States
AU: Bartlein, P J
EM: bartlein@uoregon.edu
AF: University of Oregon, Department of Geography, Eugene, OR 97403-1251 United States
AU: Shuman, B
EM: bshuman@umn.edu
AF: University of Minnesota, Department of Geography 414 Social Science Tower, Minneapolis, MN 55455 United States
AU: Williams, J W
EM: jww@geography.wisc.edu
AF: University of Wisconsin-Madison, Department of Geography 550 North Park St., Madison, WI 53706 United States
AB: When accurately and precisely dated, paleoecological data along with geochemical data and geomorphological features indicate past changes in climate. Calibrating these data in terms of standard climatic (e.g. July mean temperature) or bioclimatic (e.g. winter extreme temperatures) variables has allowed construction of paleoclimatic maps and time series that not only show the magnitude and extent of the difference in past climates but also can be compared to the output from global climate and earth-system models. Key to judging the reliability of the derived paleoclimatic estimates is the qualitative and quantitative comparison of estimates from different paleoclimatic indicators to show whether consistent or discrepant patterns exist. Here "multi-proxy" studies of independent paleoclimatic indicators from single cores, single basins, and multiple sites are providing many new opportunities to test calibration methods and results. The multi-proxy studies are also allowing researchers to develop a multivariate view of climate because different types of data, whether paleoecological or geochemical, often are sensitive to different aspects of climate change. These can be temperature changes and/or moisture changes as well as changes in seasonality or climatic extremes. Recent research mapping late Quaternary pollen, geochemical, and lake-level data across eastern North America in 1000-yr intervals illustrates some the advances gained from this multi-proxy approach to the reconstruction of past climates since the last glacial maximum 21,000 years ago.
DE: 3344 Paleoclimatology
DE: 1845 Limnology
DE: 1620 Climate dynamics (3309)
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2004 AGU Fall Meeting