ENSO及其年代际异常对全球及亚洲季风降水影响的数值研究

THE NUMERICAL STUDY OF THE EFFECT OF ENSO AND ITS INTERDECADAL VARIATION ON THE GLOBAL AND ASIAN MONSOON PRECIPITATION

中文关键词:  数值试验  年代际背景  ENSO异常  降水响应

英文关键词:Numerical experiment  Interdecadal background  ENSO anomaly  Precipitation responce

中文摘要:

      根据诊断分析结果,利用LAGS改进的L9R15气候谱模式,设计了3个数值试验,讨论了不同的年代际背景下ENSO异常对全球降水,特别是对亚洲季风降水的影响。试验结果表明,在年代际的冷、暖背景下,当出现ENSO事件时,降水响应的异常场在ENSO的不同发展阶段上,表现显着不同。出现这种差异的物理过程可以用与垂直环流相联系的势函数的变化来表示。暖背景下,当ENSO处于发展时期,比冷背景下更容易出现强烈反Walker的环流,但在ENSO处于衰减期更容易产生强烈的Walker环流,这就意味着暖背景时的ENSO异常对大气影响的幅度更大。

英文摘要:

      Based on L9R15 climatic model, the results by the three numerical experiments show that the global precipitation, espectially Asian summer monso on counterpart is difference at different stage of ENSO events under the cold and warm interdecadal background. The different physics can be showed in potential function. Compared to that under the cold background, the anti-Walker cell is stronger in the increasing stage of ENSO with stronger Walker cell in the decreasing stage of ENSO under the warm background. It means that the effect of ENSO events on precipitation anomaly under the warm background is stronger than that under the cold background.