HR: 0800h
AN: GC21A-0148    [Abstracts]
TI: Detection and Attribution of Climate Change in JFM Streamflow Fractions in the Western United States
AU: * Hidalgo, H G
EM: hhidalgo@ucsd.edu
AF: Scripps Institution of Oceanography, 9500 Gilman Drive, MC 0224, La Jolla, CA 92093- 0224, United States
AU: Das, T
EM: tadas@ucsd.edu
AF: Scripps Institution of Oceanography, 9500 Gilman Drive, MC 0224, La Jolla, CA 92093- 0224, United States
AU: Cayan, D R
EM: dcayan@ucsd.edu
AF: Scripps Institution of Oceanography, 9500 Gilman Drive, MC 0224, La Jolla, CA 92093- 0224, United States
AU: Cayan, D R
EM: dcayan@ucsd.edu
AF: United States Geological Survey, 9500 Gilman Drive, MC 0224, La Jolla, CA 92093-0224, United States
AU: Pierce, D W
EM: dpierce@ucsd.edu
AF: Scripps Institution of Oceanography, 9500 Gilman Drive, MC 0224, La Jolla, CA 92093- 0224, United States
AU: Barnett, T P
EM: tbarnett-ul@ucsd.edu
AF: Scripps Institution of Oceanography, 9500 Gilman Drive, MC 0224, La Jolla, CA 92093- 0224, United States
AU: Bala, G
EM: bala@llnl.gov
AF: Lawrence Livermore National Laboratory, Mail Code L-103 7000 East Avenue, Livermore, CA 94550, United States
AU: Mirin, A
EM: mirin@llnl.gov
AF: Lawrence Livermore National Laboratory, Mail Code L-103 7000 East Avenue, Livermore, CA 94550, United States
AU: Wood, A W
EM: aww@u.washington.edu
AF: University of Washington, Civil & Env. Engineering 111 Wilson, Box 352700, Seattle, WA 98195-2700, United States
AU: Bonfils, C
EM: bonfils2@mail.llnl.gov
AF: Lawrence Livermore National Laboratory, Mail Code L-103 7000 East Avenue, Livermore, CA 94550, United States
AU: Santer, B D
EM: santer1@llnl.gov
AF: Lawrence Livermore National Laboratory, Mail Code L-103 7000 East Avenue, Livermore, CA 94550, United States
AB: This article focuses on observed shifts in the seasonality of streamflow, and is the first in a series of papers centered on the detection and attribution of hydroclimatological parameters in the western US. The optimal detection method applied here reduces the dimensionality of a problem to a univariate or low-dimensional space. In this low-dimensional space, a detection vector is used to assess the significance of the observations for a given variable with a given climate change pattern. The results of this work indicate that observed changes in the January--March streamflow fraction in the western US are detectable and can be attributed to climate change. Detection and attribution are positive even after the El Nino-Southern Oscillation and the North Pacific Oscillation signals are factored out of the analysis. In general, we find that anthropogenic greenhouse gases and sulphate aerosols have had a detectable influence on the seasonality of streamflow over the second half of the 20th century.
DE: 1600 GLOBAL CHANGE
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1622 Earth system modeling (1225)
DE: 1637 Regional climate change
DE: 1655 Water cycles (1836)
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting