Comparison of MM5 and satellite derived precipitation and wind speed during Typhoon Chanchu (2006) in the South China Sea

The Fifth Pennsylvania State University and National Center for Atmospheric Research Mesoscale Model (MM5) is applied to study the precipitation and wind speed during Typhoon Chanchu (2006). Five model runs with selected physical parameterizations and different sea surface temperature (SST) distributions are applied in the study. Simulations are evaluated using satellite observations. It is found that the control model configured with Blakadar boundary scheme, Resiner2 moisture, BM cumulus scheme and updated SST have the best results. MRF boundary scheme tends to simulate a dryer boundary layer which can greatly reduce TC´s intensity, and results in less precipitation and wind speed. Constant SST could cause a significant increase in the TC´s intensity, therefore resulting in the largest overestimation on rainfall and maximum wind speed. Uniform TC distribution before RI could reduce the TC´s intensity and heat fluxes, which can cancel out part of the overestimation of precipitation in control model.