THE DEFINITION OF THE ADVANCE AND RETREAT OF THE SUMMER MONSOON IN CHINA
THE DEFINITION OF THE ADVANCE AND RETREAT OF THE SUMMER MONSOON IN CHINA
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发表时间：
1999-09
期刊：
影响因子：
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通讯作者：
Wang Anyu;Wu Chi-sheng;Lin Wen-shi;Yang Yan;Fong Soi-kun;Ku Chi-meng;Leong Ka-cheng
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文献类型：
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作者：
Wang Anyu;Wu Chi-sheng;Lin Wen-shi;Yang Yan;Fong Soi-kun;Ku Chi-meng;Leong Ka-cheng
利用NCEP/NCAR2.5°×2.5°再分析逐日资料(1983~1996年)，分析了850百帕长期候平均风场和位势拟当量温度场，对中国夏季风的进退进行了新的界定。根据这个新定义，夏季风区的盛行风应为西南风(850hPa2m/S)，季风空气应为高温高湿(30°N以南为340°K，850hPa30°N以北为335°K)。由于强调了西南风，新的定义比以前更合理。夏季风的推进有三次突然的北移和四次相对静止的停留。每个稳定期都对应着中国的一条主雨带。夏季风的消退很快。8月中旬，夏季风在中国大陆消失。根据观测事实，人们可以很容易地识别出这些结果。
By using NCEP/NCAR 2.5°×2.5° reanalysis daily data (1983～1996), the long term pentadly mean wind and potential pesudo equivalent temperature fields at 850 hPa have been analysed and further the advance and retreat of the summer monsoon in China have been newly defined. According to this new definition in the summer monsoon region the prevailing wind should be southwest wind (2 m/s at 850 hPa) and the air of the monsoon should be high temperature and moisture (potential pseudo equivalent temperature 340°K in the south of 30°N and 335°K in the north of 30°N at 850 hPa). Due to the southwest wind have been emphasized, the new definition is more reasonable than before. The advance of the summer monsoon have three abrupt northward shifts and four relatively stationary stays. Each stable period is corresponding to a main rainfall belt in China. The retreat of the summer monsoon is very quick. In the middle August the summer monsoon has vanished in the mainland of China. Based on the observational fact one may easily identify these results.