澳大利亚植被覆盖对亚澳季风影响的数值模拟(II):对东亚夏季风环流的影响  

Numerical Simulation about Impact of Vegetation Cover over Australian Land on Asian-Australian Monsoon (II): Impact on Summer Monsoon System

作　　者：鲍艳[1] 吕世华[1] 刘海辉[2] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所,甘肃兰州730000 [2]解放军理工大学气象学院,江苏南京211101

出　　处：《高原气象》2006年第5期772-780,共9页Plateau Meteorology

基　　金：中国科学院知识创新重要方向性项目(KZCX3-SW-221);中国气象局兰州干旱气象研究所干旱气象科学研究基金项目(IAM200513;200608)共同资助

摘　　要：在文献[1]的基础上,对澳大利亚大陆植被覆盖变化对北半球夏季越赤道气流和东亚季风环流季节变化的影响进行了研究。结果表明,植被覆盖变化对东亚季风建立前后南风越赤道气流建立时间、强弱和南半球主要环流系统都有显著的影响。绿化导致了索马里越赤道气流的建立提前,增强了不同时期南风越赤道气流的强度,但对90°E以东来自澳大利亚高压的几支越赤道气流影响不大。同时,绿化促使南半球澳大利亚高压和马斯克林高压提前建立,西太平洋副热带高压北进提前,且强度减弱,导致西南气流更容易深入东亚内陆和西太平洋。这些影响促使盛夏期西南亚季风的影响区域和强度都有所扩展,对东南季风则影响不大。沙漠化则使索马里气流略微减弱,西太平洋副热带高压在春夏季节则一直偏强,至7月中旬,才有明显东撤,阻碍了越赤道气流的北上,西南季风在此影响下强度和影响范围均有所缩减。The impacts of afforestation and desertification over Australian land on the cross-equatoral flow and monsoon system in East Asia in summer are researched in this paper. Results indicated Afforestation induced the advancing of Somali cross-equatorial flow, as well as the intensifying of cross-equatorial flows at different times, while the effect was reduced in the case of the flows to the east of 90°E, which origin from Australia high. At the same time, afforestation advanced the establishment of Australia high and Mascarene high as well as the northward jump of subtropical high over West Pacific, while the intensity of the latter was weakened, then southwest flow easily extended in to West Pacific and inland East Asia in consequence. Furthermore, In afforestation experiment, establishment of the cross-equatorial southward flow advanced in time, and the northward extension of the flow was amplified. In desertification experiment, the intensity and extension of the southward flow shrank. The change of Australian landuse will cause the intensity of southwest Asia monsoon to change, while its influence on East Asia monsoon is less notable, and this is relevant to the mechanism that afforestation intensified Somali cross-equatorial flow and put relatively minor influence on the flow to the east of 90°E on the other hand. While desertification weakened the Somali flow. the subtropical high on West Pacific in desertification was comparably intense in both spring and summer, and it baffled the northward blow of cross-equatorial flow. It is also demonstrated that Australian landuse change influences the time when East Asian summer monsoon established as well as the seasonal conversion characteristics, especially for south-west monsoon.

关 键 词：澳大利亚植被变化 东亚季风 季节转换 越赤道气流 

分 类 号：P425.42[天文地球—大气科学及气象学]