HR: 08:15h
AN: U41B-02    [Abstracts]
TI: Drought and Patterns of Circulation Inferred From Tree-Ring Data in Western North America
AU: * Woodhouse, C A
EM: conniew1@email.arizona.edu
AF: University of Arizona, Dept. of Geography and Reg. Dev., 409 Harvill Bldg., Tucson, AZ 85721, United States
AU: Cook, E R
EM: drdendro@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10964, United States
AB: Tree-ring data are excellent proxies for climate in western North America and have been used to reconstruction a variety of hydroclimatic variables. This study takes advantage of a network of PDSI reconstructions and reconstructions of Colorado River streamflow to examine drought in the upper Colorado River basin over the past five centuries, with a focus on multidecadal periods of drought. The upper Colorado River basin is located in a zone that is transitional with respect to a number of circulation features, including ENSO. As a result, the circulation patterns that lead to drought in this region have not been well identified. This study uses the PSDI reconstruction network as the basis for a set of indices that describes major spatial patterns of drought across western North America. These drought pattern indices are compared to Colorado River reconstructed flow to investigate widespread hydroclimatic patterns during periods of drought in the basin over past centuries. Since hydroclimatic patterns, such as the winter moisture dipole between the northwestern and southwestern US, may be indicators of ocean/atmospheric conditions, these proxy-based indices derived may be useful for documenting the association between upper Colorado River basin drought and ocean/atmosphere circulation in the past.
DE: 1635 Oceans (1616, 3305, 4215, 4513)
DE: 1812 Drought
DE: 3344 Paleoclimatology (0473, 4900)
SC: Union [U]
MN: 2007 Joint Assembly