P23  Improving Summer-Time Precipitation Associated with the North American Monsoon using MODIS Sea Surface Temperatures

Meyer, Jon, Jiming Jin, Ripley McCoy, Utah State University

This study attempts to understand and correct processes within the Weather Research and Forecasting (WRF) model version 3.3 coupled with the Community Land Model (CLM) version 4.0 responsible for underestimated summer-time precipitation associated with the North American Monsoon. Analysis shows that a cold bias is seen in the Gulf of CaliforniaÕs sea surface temperature (SST) for WRF employing National Centers for Environmental Prediction (NCEP) reanalysis data. This cold bias reduces the amount of moisture transported to the Southwestern United States during the summer monsoon season, resulting in under-prediction of precipitation in that region. Thus we integrated high-quality Moderate Resolution Imaging Spectroradiometer (MODIS) SST data with WRF-CLM to generate improved summer monsoon precipitation in the Southwest. Further, analysis was conducted using WRF-CLM to examine how the land surface temperature in the Southwest affects regional- and synoptic-scale atmospheric processes and monsoon precipitation.