HR: 0830h
AN: A31C-0061    [PDF]
TI: Synoptic Meteorology of U.S. Southwest-Great Plains Summer Precipitation
AU: * Garfin, G
EM: gmgarfin@email.arizona.edu
AF: University of Arizona, Institute for the Study of Planet Earth 715 N. Park Ave., 2nd Fl., Tucson, AZ 85721-0156 United States
AU: Maddox, R
EM: maddox@atmo.arizona.edu
AF: University of Arizona, Department of Atmospheric Sciences P.O. Box 210081, Tucson, AZ 85721-0081 United States
AB: In this study, daily synoptic weather patterns are examined for simultaneous precipitation characteristics of bioclimatic subregions of the Southwest U.S. and Great Plains. The bioclimatic regions take into account gradients caused by differences in topography, continentality, and diurnal precipitation characteristics; such gradients result in great differences in precipitation total that have ramifications for decision makers. Precipitation and synoptic patterns were analyzed for subregions with strong inverse precipitation correlations. Subregional precipitation characteristics (i.e., wetness or dryness) and associated synoptic patterns were defined based on the percent raininess from the raw regional precipitation data for the period from 1948 through 2002. Percent raininess is defined as the percent of stations in the region reporting measurable daily rainfall. Wet days are defined as those during which at least 60% of stations report daily rainfall; dry days are defined as those during which 0% of stations report daily rainfall. Midtropospheric synoptic meteorological patterns and atmospheric moisture (specific humidity) were examined for all days determined to be dry in a Southwest subregion of interest and dry in a corresponding Great Plains region of interest (dry-dry), and for all other possible combinations between these regions (i.e., wet-wet, wet-dry, dry-wet). Examination of the synoptic patterns associated with these combinations for subregions with strong inverse summer season precipitation correlations indicates that a wide variety of synoptic patterns can lead to simultaneous inverse precipitation in the subregions. In addition, a variety of synoptic patterns can lead to simultaneous wetness or dryness in these distant subregions. The findings of this research are at times dramatically different than past results reported in the literature. A number of examples and comparisons will be shown.
DE: 0399 General or miscellaneous
DE: 1620 Climate dynamics (3309)
DE: 3309 Climatology (1620)
DE: 3354 Precipitation (1854)
DE: 3364 Synoptic-scale meteorology
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting