8.2    Evaluation of WRF Regional Climate Simulations of Wet and Dry Years Over the Southern High Plains

Lisi Pei 1,2, Nathan Moore 1, Sharon Zhong 1, Zhiqiu Gao 2, Lifeng Luo 1, Xindi Bian 3, Warren E. Heilman 3,   1. Michigan State University, East Lansing, Michigan 2. Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China 3. North Central Research Station, USDA Forest Service, East Lansing, Michigan

The suitability of WRF v3.3.1 as a regional climate downscaling tool has been evaluated through half-year simulations over the Southern High Plains. The growing season (Apr.-Sept.) of three pairs of dry and wet years are selected to verify the performance of the WRF model initialized with different GCM data (CFSR&NARR). Sensitivity tests are done with different domain settings and multiple physical schemes. Results show that without any spectral nudging under a growing season of dynamical downscaling, WRF reproduced the daily spatial averaged mean precipitation and temperature values over the Southern High Plains reasonably well. Patterns of monthly accumulated precipitation in wet years agree better with observation than those of the dry years. Wet years also have lower biases for the daily spatially averaged mean (and max/min) temperature compared to dry years. The model performance is found to be sensitive to a set of factors including driving GCM data, domain settings and physical schemes.