区域气候模式RegCM3对中国夏季降水的模拟

利用意大利国际理论物理中心（ICTP）最新发布的区域气候模式RegCM3检验我国包括青藏高原地区夏季降水的模拟能力。初始值及边界值取自美国国家环境预测中心（NCEP）和国家大气中心（NCAR）的全球再分析资料。模式积分时间为2005年5月1日到2005年8月31日,考虑到模式的“spin-up”时间,只对6月1日-8月31日的模式结果进行分析。模式水平分辨率取为60km,范围包括整个青藏高原在内的我国及周边地区（14°-55°N,70°-140°E）。结果表明：RegCM3具有模拟我国夏季降水主要分布特征的能力,尤其在观测站点稀少的青藏高原地区可提供局地降水分布的较可靠信息。模式较好地模拟了包括整个青藏高原在内的我国区域降水的月际尺度变化和空间分布等基本特征,但对我国东南地区的夏季降水模拟能力有待进一步提高。

Numerical simulation of summer precipitation in China by using a regional climate model(RegCM3)

The capability of the new regional climate model RegCM3 to simulate the summer precipitation over the whole China including the Tibetan Plateau by using the NCEP reanalysis 2 data provided by the NCEP/NCAR available at 6hr intervals with a resolution of 2.5°× 2.5° as both the initial and lateral boundary conditions. The model is investigated from 1 May to 31 August 2005 and has 150and 80 grids in the zonal and meridional directions, respectively, with a grid space of 60km covering the whole China and surrounding areas of 14°-55°N, 70°- 140°E. By comparison of the observa-tion the results show that the RegCM3 model not only has the ability to simulate the basic character of the temporal evolu-tion of the area- averaged precipitation and the monthly mean precipitation spatial pattern but also the daily precipitation intensity distribution. Especially in the Tibetan Plateau region the model simulation can provide more reliable information of the local precipitation for the region of rare observation station. The evolution and spatial distribution of the precipita-tion in the model are reasonable and comparable to the observations. Further work must be done to improve the perfor-mance of the RegCM3 of the several important regional biases in China. More cases are simulated to identify the systemat-ic errors and to improve the model physics, and thus to make the model a useful tool for the support of the regional precipi-tation research in China.