HR: 1340h
AN: H43B-0505    [Abstracts]
TI: Global Climate Model Scenarios for Precipitation in North America
AU: * Ahlfeld, D
EM: ahlfeld@ecs.umass.edu
AF: Dept. of Civil and Environmental Engineering, University of Massachusetts, Amherst, MA 01003 United States
AB: Global and regional climate models are valuable tools for assessing the impacts of alternate greenhouse emission scenarios on future climate. In recent years, the number of models available has increased and the sophistication of these models has generally improved. Recently, the Intergovernmental Panel on Climate Change has made model output from a range of global climate models available through the Program for Climate Model Diagnosis and Intercomparison at Lawrence Livermore National Laboratory. A comparison is made between observed and predicted precipitation from 18 global climate models for the period 1979 to 2000 in three regions of North America using monthly averaged output of the 20C3M experiment (climate of the 20th century) and the CPC Merged Analysis of Precipitation (CMAP) data. Precipitation averaged over monthly, seasonal and annual time periods is considered. The three regions encompass western, central and eastern North America excluding Alaska, northern Canada and Latin America. Most models compare well with observed precipitation for the central and eastern regions at all time scales. Discrepancies between model results and observed precipitation are generally smallest in summer and fall seasons. For the western region, models are less successful in comparison to observed precipitation. A subset of models, those deemed to be most successful at reproducing observed precipitation, are used to analyze the impact of various greenhouse gas emission scenarios (including the Commit and SRESB1 experiments) on precipitation in the mid- and late-21st century.
DE: 1805 Computational hydrology
DE: 1807 Climate impacts
DE: 1854 Precipitation (3354)
SC: Hydrology [H]
MN: Fall Meeting 2005