区域气候模式对华北夏季降水的气候模拟

SIMULATION OF SUMMER PRECIPITATION OVER NORTH CHINA IN 1991 AND 1994 WITH A NCAR REGIONAL CLIMATE MODEL

使用美国ＮＣＡＲ 区域气候模式ＲｅｇＣＭ２ 对１９９１ 和１９９４ 年我国华北夏季降水进行了气候模拟研究，以检验ＮＣＡＲ 区域气候模式对华北夏季降水的气候预测能力。模拟结果表明，该模式能较好地模拟华北夏季降水的主要分布特征，对华北少水年（１９９１ 年） 和多水年（１９９４ 年） 夏季降水的模拟都比较成功。模式还能较好地模拟夏季季风的发展过程，对环流场的模拟也与分析场比较一致，因而该模式可以用于研究和预测华北夏季降水以及华北水资源。

We used a recent version of the regional climate model (RegCM2) developed at the National Center for Atmospheric Research (NCAR) to simulate summer precipitation over North China in 1991 and 1994 and to validate the capability for studying regional climate change. The RegCM2 is a modified version of the NCAR Pennsylvania State University Mesoscale Model (MM4) for climate application. The model vertical resolution is 14 levels and horizontal resolution is 40 km. The domain is centered at (100°E,37.5°N) and the total grids point is about 105×95. The simulation period is June to August in 1991 and 1994, and the initial and boundary condition come from ECMWF analyses of observations. The result indicates that the RegCM2 model can simulate reasonably well spatial patterns of the atmospheric circulation, precipitation, soil moisture and runoff in 1991 and 1994. There are the drought in 1991 and more rain in 1994 in North China. The model simulated wind vectors also agree with the observation reasonably well this two years. It shows that the model has good capability to study regional climate change in North China.