This study presents a dynamically downscaled climatology over East Asia using the non-hydrostatic Weather Research and Forecasting （WRF） model, forced by the Twentieth Century Reanalysis （20CR-v2）. The whole exper...This study presents a dynamically downscaled climatology over East Asia using the non-hydrostatic Weather Research and Forecasting （WRF） model, forced by the Twentieth Century Reanalysis （20CR-v2）. The whole experiment is a 111-year （1900--2010） continuous run at 50 km horizontal resolution. Comparisons of climatic means and seasonal cycles among observations, 20CR-v2, and WRF results during the last 30 years （1981-2010） in China are presented, with a focus on sur- face air temperature and precipitation in both summer and winter. The WRF results reproduce the main features of surface air temperature in the two seasons in China, and outperform 20CR-v2 in regional details due to topog- raphic forcing. Summer surface air temperature biases are reduced by as much as 1℃-2℃. For precipitation, the simulation results reproduce the decreasing pattern from Southeast to Northwest China in winter. For summer rainfall, the WRF simulation results reproduce the correct magnitude and position of heavy rainfall around the southeastern coastal area, and are better than 20CR-v2. One of the significant improvements is that an unrealistic center of summer precipitation in Southeast China present in 20CR-v2 is eliminated. However, the simulated results underestimate winter surface air temperature in northern China and winter rainfall in some regions in southeastern China. The mean seasonal cycles of surface air tempera- ture and precipitation are captured well over most of sub-regions by the WRF model.展开更多
基金supported by the National Basic Research Program of China (Grant No. 2013CB430201)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA11010404)
文摘This study presents a dynamically downscaled climatology over East Asia using the non-hydrostatic Weather Research and Forecasting （WRF） model, forced by the Twentieth Century Reanalysis （20CR-v2）. The whole experiment is a 111-year （1900--2010） continuous run at 50 km horizontal resolution. Comparisons of climatic means and seasonal cycles among observations, 20CR-v2, and WRF results during the last 30 years （1981-2010） in China are presented, with a focus on sur- face air temperature and precipitation in both summer and winter. The WRF results reproduce the main features of surface air temperature in the two seasons in China, and outperform 20CR-v2 in regional details due to topog- raphic forcing. Summer surface air temperature biases are reduced by as much as 1℃-2℃. For precipitation, the simulation results reproduce the decreasing pattern from Southeast to Northwest China in winter. For summer rainfall, the WRF simulation results reproduce the correct magnitude and position of heavy rainfall around the southeastern coastal area, and are better than 20CR-v2. One of the significant improvements is that an unrealistic center of summer precipitation in Southeast China present in 20CR-v2 is eliminated. However, the simulated results underestimate winter surface air temperature in northern China and winter rainfall in some regions in southeastern China. The mean seasonal cycles of surface air tempera- ture and precipitation are captured well over most of sub-regions by the WRF model.
