Impacts of Different Cumulus Convective Parameterization Schemes on Regional Climate Model Simulation over Xinjiang

The NCEP-FNL dataset is used to provide initial and boundary fields for the WRF model. Seven cumulus convective parameterization schemes are applied in this model to simulate climate over Xinjiang region with 10-km horizontal resolution. The study is focused on spatial distributions and temporal evolutions of meteorological elements. The analysis results are as follows:1) The model with the seven Cumulus Convection Parameterization Schemes (CCPS) can well simulate the vertical structure of the atmosphere and the spatial pattern of annual and rainy seasonal precipitation and temperature. 2) For different regions, the correlation coefficients between simulated and observed precipitation are within the range of 0.20 to 0.85 and the correlation coefficients between simulated and observed temperature are above 0.98. In Xinjiang region, the humidity in the lower layer is drier in the simulations with various schemes than in the observations, and the simulated temperature is cooler than the observations. As a result, the simulated atmospheric stratification tends to be more stable than observations, which leads to precipitation underestimation in the simulations. The opposite is true for the Tianshan area in Xinjiang. 3) Precipitation and temperature simulated by WRF with new Grell and Kain-Fritsch (new Eta) schemes are better that with other CCPS. Therefore, it is necessary to carefully select appropriate cumulus convective parameterization schemes when using WRF model to simulate climate in Xinjiang.