摘要
利用NCEP/NCAR 1958~1997年全球SST、850hPa与200hPa风场再分析资料,以及1958-1997年全印度降水指数资料,从环流与降水两方面定义出南亚夏季风典型强年为1961、1970年,典型弱年为1965、1979、1987年。并针对所定义的强弱年采用合成分析与相关分析方法,分析了南亚夏季风强弱年前期与同期的阿拉伯海海温变化特征,发现:4月阿拉伯海海温越高(低),南亚夏季风越强(弱),而7月相反,海温越高(低),季风越弱(强);在南亚夏季风典型强年,阿拉伯海海温年变幅较大;沿赤道的Yoshida-Wyrtki Jet较强,并且在南亚夏季风强年的前期4月,南北半球哈德莱环流较弱,而弱年较强。7月,不论强弱年,热带印度洋上空的经圈环流以南亚夏季风经圈环流为主。
By using NCEP/NCAR the global SST data, the wind fields of 850 hPa and 200 hPa reanalysis grid data and the all Indian rainfall indices, 1961 and 1970 were defined to be typically strong SASM years while 1965, 1979 and 1987 typically weak SASM years. Moreover, we used composition and correlation methods to analyze respectively the variations of Arabian Sea SST during the prophase (Apr.) and the corresponding periods (Jul.) in the strong/weak SASM years. We found if the Arabian Sea SST in April is high, the SASM will be strong, vice versa. However, if the SST in July is high, the SASM will be weak, and also vice versa. In addition, in strong SASM years the range of the SST variations was bigger and Yoshida-Wyroki Jet was stronger. In July the SASM meridional circulation became domination over the tropical Indian Ocean.
出处
《热带气象学报》
CSCD
北大核心
2006年第4期374-379,共6页
Journal of Tropical Meteorology