HR: 0800h
AN: PP11A-1428    [Abstracts]
TI: A 626-Year Summer Temperature Reconstruction for the Central Rocky Mountains
AU: * Woodhouse, C A
EM: connie.woodhouse@noaa.gov
AF: NOAA National Climatic Data Center, Paleoclimatology Branch, 325 Broadway, E/CC23, Boulder, CO 80305 United States
AU: Brown, P M
EM: pmb@rmtrr.org
AF: Rocky Mountain Tree-Ring Research, Inc., 2901 Moore Lane, Fort Collins, CO 80526 United States
AU: Hughes, M K
EM: mhughes@ltrr.arizona.edu
AF: University of Arizona, Laboratory of Tree-Ring Research, 105 W. Stadium, Tucson, AZ 85721 United States
AB: A new summer temperature reconstruction has been generated for the central Rocky Mountains, filling a spatial gap in multi-century temperature reconstructions in western North America between the Great Basin and the Canadian Rockies. The reconstruction was calibrated with regional May-August temperatures from the Climatic Research Unit temperature data set using the years 1899-1950. A regression equation incorporated total ring-width and maximum density chronologies from two sites, and explained 45.6% of the variance in the instrumental record of the variance in the instrumental record. The full reconstruction, AD 1325-1950, shares a number of the major features seen in other North American and Northern Hemisphere summer temperature reconstructions. Since 1950, the relationship between tree growth at these sites and summer temperatures has changed. Moving correlation analysis with monthly temperature and precipitation and tree-ring density suggest a shift in the response to temperature, moving from May-August to May-June and September, perhaps an indication of a response to a longer growing season. There is also a suggestion of an increased sensitivity to spring precipitation. If these changes are due to regional warming, it is possible that the reconstruction may be less reliable during previous warm periods. A method is presented which evaluates the strength of the correlation between ring-width and maximum density series over time to assess possible periods of less reliable estimates of temperature.
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1630 Impacts of global change (1225)
DE: 3344 Paleoclimatology (0473, 4900)
DE: 4920 Dendrochronology
SC: Paleoceanography and Paleoclimatology [PP]
MN: Fall Meeting 2005