Campus Units

Geological and Atmospheric Sciences, Agronomy

Document Type

Article

Publication Version

Published Version

Publication Date

11-2003

Journal or Book Title

Journal of Climate

Volume

16

Issue

22

First Page

3841

Last Page

3847

DOI

10.1175/1520-0442(2003)016<3841:TSOOAS>2.0.CO;2

Abstract

Precipitation intensity spectra for a central U.S. region in a 10-yr regional climate simulation are compared to corresponding observed spectra for precipitation accumulation periods ranging from 6 h to 10 days. Model agreement with observations depends on the length of the precipitation accumulation period, with similar results for both warm and cold halves of the year. For 6- and 12-h accumulation periods, simulated and observed spectra show little overlap. For daily and longer accumulation periods, the spectra are similar for moderate precipitation rates, though the model produces too many low-intensity precipitation events and too few high-intensity precipitation events for all accumulation periods. The spatial correlation of simulated and observed precipitation events indicates that the model's 50-km grid spacing is too coarse to simulate well high-intensity events. Spatial correlations with and without very light precipitation indicate that coarse resolution is not a direct cause of excessive low-intensity events. The model shows less spread than observations in its pattern of spatial correlation versus distance, suggesting that resolved model circulation patterns producing 6-hourly precipitation are limited in the range of precipitation patterns they can produce compared to the real world. The correlations also indicate that replicating observed precipitation intensity distributions for 6-h accumulation periods requires grid spacing smaller than about 15 km, suggesting that models with grid spacing substantially larger than this will be unable to simulate the observed diurnal cycle of precipitation.

Comments

This article is from J. Climate, 16, 3841–3847. doi: http://dx.doi.org/10.1175/1520-0442(2003)016<3841:TSOOAS>2.0.CO;2. Posted with permission.

Copyright Owner

American Meteorological Society

Language

en

File Format

application/pdf

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