Simulation Evaluation Of Air Temperature And Precipitation On The Qinghai-Tibet Plateau By CWRF Models

Based on the simulation results of 30 GCMs from CMIP6 and CWRF with 3 resolutions and 27 physical parameterization schemes,this paper analyzes the bias of climate simulation on the plateau and its relationship with resolution and parameterization scheme selection.The applicability of different parameterization schemes of CWRF model on plateau is compared,and the reasons for the deviation of temperature and precipitation are analyzed.Finally,the influence of Plateau Atmospheric Heat Source on East Asia Climate and the influence of optimized plateau climate simulation on China regional climate simulation are analyzed.The main conclusions are as follows:(1)The simulation of air temperature on the plateau in winter is generally low,and there is a cold deviation mainly in the south slope of the plateau;the simulated summer precipitation of the plateau is abnormally high;compared with the global model,CWRF significantly reduces the simulation deviation of the annual cycle of temperature and precipitation,and can well simulate the interannual variation;CWRF comprehensively reduces the bias of ERI which is its driving field,and improves correlation coefficient of interannual variation;(2)The horizontal resolution of models has a significant impact on the plateau precipitation simulation,and the precipitation deviation first decreases and then increases with the increase of the resolution,and 30 km has the best effect on the plateau precipitation climate simulation;however,the resolution has little impact on the plateau temperature simulation,improvement of resolution leads to increase of deviation;Besides,the selection of physical parameterization scheme has a significant impact on the plateau temperature and precipitation simulation,the radiation scheme has a greater impact on the temperature,and the cumulus scheme has a greater impact on the precipitation.(3)The simulation bias of radiation and cumulus over the plateau leads to the bias of tropospheric atmospheric temperature over the plateau,which affects the simulation of circulation and water vapor,and finally affects the temperature and precipitation.This paper provides a basis for the resolution and parameterization scheme selection of regional climate simulation over the plateau.