亚澳季风区内水汽汇的准两年振荡及其与大气环流的关系

利用1950-2000年大气视水汽汇资料,分析了亚澳季风区内水汽汇准两年振荡的变化特征及其与大气环流的关系.亚澳季风区内水汽汇有显著的准两年振荡,其关键区位于西太平洋暖池、孟加拉湾、东南印度洋和西南印度洋,它们对应3种遥相关型.当暖池水汽汇偏强时,我国华南为偏北风距平,东亚季风区水汽汇偏弱;印度洋水汽汇距平呈现为偶极子分布,东南印度洋附近水汽汇偏强时,东南印度洋至赤道西印度洋为偏西风距平,赤道西印度洋水汽汇偏弱;孟加拉湾水汽汇偏强时,孟加拉湾至西南印度洋为偏南风距平,西南印度洋的水汽汇偏弱.反之亦然.

Tropical Biennial Oscillation of Moisture Sink over Asian-Australian Monsoon Region and its Relationship with Atmospheric Circulation

Using the apparent moisture sink data from 1950 to 2000, the tropical biennial oscillation of moisture sink over Asian-Australian monsoon (AA monsoon) region and its relationship with the atmospheric circulation are studied. The results show that the west pacific warm pool, Bay of Bengle, southeast Indian Ocean and southwest Indian Ocean are the key regions of the biennial oscillation in AA monsoon region. They correspond to three main teleconnection patterns. When the moisture sink ( < Q2>) over the west Pacific warm pool is stronger, it is northerly wind anomaly over Southern China, over the East-Asian monsoon region is weaker; there is apparent dipole mode in the Indian Ocean. When over the southeast Indian Ocean is stronger, it is westerly wind anomaly from the southeast to western equatorial Indian Ocean, < Q2> over the western equatorial Indian Ocean is weaker. When over Bay of Bengle is stronger, it is southerly wind anomaly from the Bay of Bengle to the southwest Indian Ocean, < Q2> over the southwest Indian Ocean is weaker, and vice versa.