摘要
为给汉江流域秋汛预报提供一定参考,基于1961～2016年NCEP/NCAR逐月再分析资料(2. 5°×2. 5°)分析东亚季风区9～10月水汽输送通量分布情况,并结合对水汽通量散度的分析,得出了秋汛期(9～10月)影响汉江流域主要有3条水汽通道,分别为:①来自西太平洋偏东方向的水汽输送通道;②来自孟加拉湾经中南半岛的西南方向的水汽输送通道;③来自副热带地区经青藏高原西北方向的水汽输送通道,第③条水汽通道强度明显强于其余2个水汽通道。通过分析3条水汽通道强度与汉江流域降水的相关关系发现:秋汛期(9～10月),②③两条水汽通道对汉江流域降雨均有较大影响,而第①条水汽通道对汉江流域降雨的影响较小。利用国家气候中心提供的1961～2016年6～10月逐月环流指数资料,初步探讨6～8月及9～10月副热带高压的各项指数及印缅槽强度指数与3条水汽通道的关联,得出:6～8月、9～10月,副热带高压的强度及面积仅与第①条水汽通道呈现明显负相关,而印缅槽强度与3条水汽通道均呈现明显的负相关,当6～8月、9～10月印缅槽强度偏弱时,均有利于9～10月3条水汽通道强度偏强,因此有利于9～10月汉江流域降雨偏多。
In order to provide a certain reference for the autumn flood forecasting in the Hanjiang River basin,we analyze the distribution of water vapor transport flux in the East Asian Monsoon Region from September to October based on 1961-2016 NCEP/NCAR monthly reanalysis data (2. 5 ° x 2. 5 °),and draw the following conclusions by combining with the analysis of water vapor flux divergence. In autumn flood season (September to October),there are three main channels of water vapor reaching the Hanjiang River basin,respectively,a slightly east water vapor transport channel in west Pacific;a southwest water vapor transport channel from the Bengal bay through the Indochina Peninsula;a northwest water vapor transport channel starting subtropical region and passing through the Qinghai-Tibet Plateau. The third water vapor channel is obviously stronger than that of the other two channels. By analyzing the correlations between the intensity of three water vapor channels and rainfall in the Hanjiang River Basin,it is found that in autumn flood season (September to October),the second and third water vapor transport channels have significant influence on the rainfall of the Hanjiang River basin,and the first water vapor transport channel has less effect on the rainfall of the Hanjiang River basin. We discuss the correlations between the indexes of subtropical high pressure belt and the strength of India-Burma trough with the three water vapor channels from June to August and September to October using monthly circulation index data from June to October in 1961-2016 provided by the national climate center. The results show that from June to August and September to October,the intensity and area of subtropical high pressure belt are negatively correlated with the first water vapor transport channel only,but the intensity of India-Burma trough is negatively correlated with the three water vapor channels. When the India-Burma trough is weak,it is in favor to the strengthening of the three water vapor channels from September to October,and further it is in favor to rainfall in the Hanjiang River basin.
作者
邢雯慧
王坚红
张方伟
苗春生
XING Wenhui;WANG Jianhong;ZHANG Fangwei;MIAO Chunsheng(Bureau of Hydrology,Changjiang Water Resources Commission,Wuhan 430010,China;Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,Nanjing University of Information Science&Technology,Nanjing 210044,China;College of Atmospheric Science,Nanjing University of Information Science&Technology,Nanjing 210044,China;Nanjing Xinda Institute of Meteorological Science&Technology,Nanjing University of Information Science&Technology,Nanjing 210044,China)
出处
《人民长江》
北大核心
2019年第2期101-106,共6页
Yangtze River
基金
国家自然科学基金面上项目(41276033)
国家自然科学基金青年科学基金项目(41805033)
关键词
秋汛期
水汽通道
印缅槽强度
副热带高压
汉江流域
autumn flood season
water vapor transport channel
India-burma trough
subtropical high pressure belt
Hanjiang River
