东亚副热带夏季风槽的气候特征及其与南海夏季风槽的比较  

CLIMATOLOGICAL FEATURES OF EAST ASIAN SUBTROPICAL SUMMER MONSOON TROUGH AND ITS COMPARISON WITH SOUTH CHINA SEA SUMMER MONSOON TROUGH

作　　者：王黎娟[1] 何金海[1] 管兆勇[1] 

机构地区：[1]南京信息工程大学江苏省气象灾害重点实验室

出　　处：《气象学报》2006年第5期583-593,共11页Acta Meteorologica Sinica

基　　金：国家基础研究发展规划项目(2004CB418303;2004CB418302);江苏省高等学校研究生创新计划(E30000008098-3)

摘　　要：利用NCAR/NCEP再分析资料,从气候特征角度研究了东亚副热带夏季风槽的结构和演变特征及其与南海夏季风槽的区别。结果表明,无论是辐合还是对流,南海夏季风槽都强于副热带夏季风槽。南海夏季风槽伸展高度较低,位置少变;而副热带夏季风槽伸展高度较高,并且随高度向北倾斜。南海夏季风槽建立早且突然,表现为对流层低层正相对涡度突然出现,其撤退缓慢;副热带夏季风槽则是渐进式建立,表现为低层云贵高原、广西地区的正相对涡度逐步向东北方向扩展,其撤退较快。南海夏季风槽建立过程中东西风向逆转是一个很明显的指示因子,而副热带夏季风建立过程没有伴随明显的风向逆转,主要特征是西风增强。南海夏季风槽不具备锋面性质,副热带夏季风槽则具备明显的锋面性质。Based on the NCEP/NCAR reanalysis data, an investigation has been carried on the climatologically structural and evolutional features of the East Asian subtropical summer monsoon trough （STSMT） and its comparison with the South China Sea summer monsoon trough （SCSSMT）. The results show that the SCSSMT is stronger whether in convergence or convection than the STSMT. The STSMT extends up to a higher level and inclines northward with altitude, however, the SCSSMT extends up to a lower level, and its position is seldom changed. The SCSSMT onsets early and abruptly with the low level positive relative vorticity appearing suddenly, and retreats slowly, but the STSMT establishes step by step with the positive relative vorticity initially over the Yunnan - Guizhou Plateau and Guangxi areas spreading gradually northeastward, and withdraws rapidly. The onset of SCSSMT is obviously indicated by the reverse of the easterly, but the establishment of STSMT is characteristic of the westerly enhancement. The STSMT has clearly frontal property, yet the SCSSMT has not.

关 键 词：东亚副热带 南海 夏季风槽 气候特征. 

分 类 号：P425.42[天文地球—大气科学及气象学]