摘要
1961—2000年的ECMWF逐日格点资料和印度降水量资料,分析研究表明南亚地区的气候,特别是印度的夏季降水存在明显的准两年振荡(TBO)特征。为了研究南亚地区TBO的机理,定义了一个统一的南亚季风指数来描述南亚冬季风和南亚夏季风以及两者之间的转换特征。通过研究南亚季风指数的异常变化特征,发现南亚冬季风和南亚夏季风存在相互影响和相互作用的关系。通常来说,强(弱)的南亚冬季风后南亚夏季风活动一般偏弱(强);另外,偏强(弱)的南亚冬季风一般发生在强(弱)南亚夏季风活动后。南亚夏季风和南亚冬季风的这种循环演变特征可能是南亚地区出现TBO的重要机制之一。
Analysis shows, once again, that there is obvious tropospheric biennial oscillation （TBO） in the climate of South Asia, especially with the Indian summer monsoon rainfall. In order to explore the mechanism of TBO in the South Asian region, we defined a unified South Asian monsoon index to depict the South Asian summer monsoon （SASM） and South Asian winter monsoon （SAWM） and the transition features between SASM and SAWM. Through further analysis, mutual impacts and interactions between the anomalies of SASM and SAWM were discovered. Normally, a strong SAWM precedes a weak SASM while a weak SAWM comes before a strong SASM, and a strong SASM is favorable for a weak SAWM while a weak SAWM always happens after a weak SASM. Such results suggested a cyclic evolvement of the SASM and SAWM, which may be an important mechanism for the TBO to appear in the South Asian region.
出处
《热带气象学报》
CSCD
北大核心
2013年第1期1-6,共6页
Journal of Tropical Meteorology
基金
国家自然科学基金项目(U0833602)
"973"项目(2010CB950400)共同资助
