摘要
利用NCEP/NCAR的1958～1998年再分析资料研究夏季东亚季风区水汽输送特征,综合这些特征划分出夏季输送到中国大陆主要有来自低纬的三条水汽通道:西南通道、南海通道和东南通道,此外在高纬还有一条很弱的西北通道,分别体现了南亚季风、南海季风、副热带季风和中纬度西风带对中国夏季降水的影响。定义和计算了四条水汽通道强度指数来表征水汽通道的强弱,并研究其年际变化。相关分析表明四条水汽通道对我国夏季降水的影响范围分别是:西南通道是华南中部和西南边境降水的水汽来源,南海通道对华南降水有直接贡献,东南通道为长江流域降水输送水汽,西北通道则为黄河中上游及华北东部降水输送水汽。物理分析显示,水汽输送异常与大气环流异常直接相关,而与同期水汽源地的海温异常关系不密切,海洋的作用主要体现在前期大范围的海温异常分布上。
The characteristics of water vapor transfer over the East Asia summer monsoon region are studied by using NCEP/NCAR reanalysis data from 1958 to 1998. The results show that in summer there are four vapor inflow corridors to China: southwest corridor, South China Sea corridor, southeast corridor and northwest corridor. This shows that the impact of South Asia monsoon, South China Sea monsoon, subtropical monsoon and middle latitude westerly on summer rainfall anomaly over China, respectively. The four intensity indexes of water vapor transfer are defined and calculated, and their interannual variations are studied. Influencing areas of the four vapor inflow corridors to China are located by correlation analysis. Finally, the relationship between water vapor transfer anomaly and physical factors is discussed. The results show that the intensity of vapor inflow corridors is associated directly with atmosphere circulation anomalies, not with the same term SST.
出处
《热带气象学报》
CSCD
北大核心
2004年第4期401-408,共8页
Journal of Tropical Meteorology
基金
"我国重大气候灾害的机理和预测理论研究"(G1998040901)资助
关键词
水汽通道
夏季风
降水异常
ENSO
大气环流
water vapor transfer
summer monsoon
rainfall anomaly
ENSO
atmosphere circulation
