摘要
利用NCEP/NCAR1957~2001年45年逐日的再分析资料,从地面开始积分计算整层的水汽输送通量,从气候平均的角度分析了亚澳季风区大尺度水汽输送的季节转换演变特征。分析发现,亚澳季风区水汽输送由冬季向夏季的季节转换的基本特征是:夏季大值输送带的建立及其自西向东伸展,伴随着斯里兰卡低涡活动、自南向北的越赤道输送和副高的东撤、南海夏季风建立等一系列天气气候事件;而冬季形势的建立则是副高南侧东风输送带的西伸,伴随夏季大值输送带的断裂、西撤,最后形成亚洲低纬东风输送带,进而形成由北向南的越赤道输送以及澳大利亚和南印度洋夏季风水汽输送。伴随着冬、夏季节转换,中南半岛以西和以东地区的西风水汽输送的经向移动表现出完全不一样的特征,表明印度季风和东亚-西太平洋季风的形成机制有很大不同。
The climatological features of large-scale vertically integrated moisture transport (VIMT) in seasonal transition over Asian-Australian monsoon (AAM)regions have been investigated using NCEP/NCAR analysis for the 1957-2001 period. It is shown that the basic features of moisture transport in seasonal transition from winter to summer are establishment of summertime strong transport belt and its eastward expansion accompanying with a series of synoptic and climatological events, such as the activity of Sri Lanka low vortex, the occurrence of strong northward cross-equatorial transport, the eastward retreat of the West Pacific subtropical high(WPSH) and the onset of South China Sea(SCS) summer monsoon, etc. While the main characteristics in seasonal migration from summer to winter are characterized by the westward expansion of easterly moisture transport originating from western pacific along the southern periphery of WPSH. It is also strongly characterized by the breakup and westward retreat of summertime strong transport belt, the formation of Asian low-latitude easterly transport belt, and then occurrence of southward cross-equatorial transport and summer westerly transport over Australian and Southern Indian Ocean. Further analysis shows that associated with evolving annual cycle, the meridional migration features of westerly moisture transport in areas to the east and west of Indochina Peninsular are quite different, which may also denote different forming mechanisms between the Indian monsoon and East Asian-Western Pacific monsoon.
出处
《热带气象学报》
CSCD
北大核心
2006年第2期138-146,共9页
Journal of Tropical Meteorology
基金
广东省自然科学基金(NO.0400391)
热带海洋气象科学研究基金共同资助
关键词
亚澳季风区
垂直积分的水汽输送
季节转换
中南半岛
Asian-Australian monsoon(AAM) regions
vertically integrated moisture transport(VIMT)
seasonal transition
Indochina Peninsular