RegCM3_IAP9L-AGCM对中国跨季度短期气候预测的回报试验研究

Hindcast experiment of extraseasonal short-term summer climate prediction over China with RegCM3_IAP9L AGCM.

中文关键词:  RegCM3， 嵌套区域气候模式， 回报试验， 跨季度短期气候预测

英文关键词:RegCM3, Nested regional climate model, Hindcast experiment, Extraseasonal short term prediction

中文摘要:

      将区域气候模式RegCM3与中国科学院大气物理研究所全球大气环流模式IAP9L-AGCM进行单向嵌套，建立嵌套区域气候模式RegCM3_IAP9L-AGCM，并利用该嵌套模式对1982—2001年中国夏季短期气候进行了跨季度集合回报试验。结果表明，RegCM3_IAP9L-AGCM对高空气候变量（500 hPa位势高度场、200和850 hPa纬向风场）的回报结果与实况距平相关系数（ACC）基本为正，其回报效果好于单独使用IAP9L-AGCM的结果。除850 hPa纬向风场外，其他两个变量场回报与实况正相关的区域基本呈纬向带状分布且通过90%信度检验。在中国大部分地区（除长江下游、东北北部和西北北部外），嵌套区域气候模式回报的降水距平百分率与实况基本为正相关。RegCM3_IAP9L-AGCM 和IAP9L-AGCM对中国不同区域的夏季降水回报效果不同，前者对华南降水的回报效果明显好于后者。

英文摘要:

      The regional climate model RegCM3 has been one-way nested into IAP9L-AGCM, the nine-level atmospheric general circulation model of the Institute of Atmospheric Physics, Chinese Academy of Sciences, to perform a 20 year (1982-2001) hindcast experiment on extraseaonal short-term prediction of China summer climate. The nested prediction system is referred to as RegCM3_IAP9L AGCM in this paper. The results show that hindcasted climate fields such as 500 hPa geopotential height, 200 and 850 hPa zonal winds from RegCM3_IAP9L-AGCM have positive anomaly correlation coefficients (ACC) with the observations, and are better than those from the stand alone IAP9L-AGCM. Except for the 850 hPa wind field, the positive ACC of the other two fields with observations both pass the 90% confidence level and display a zonal distribution. The results indicate that the positive correlation of summer precipitation anomaly percentage between the nested prediction system and observations covers most parts of China except for downstream of the Yangtze River and north of Northeast and Northwest China. The nested prediction system and the IAP9L AGCM exhibit different hindcast skills over different regions of China, and the former demonstrates a higher skill over South China than the latter in predicting the summer precipitation.