长江流域旱涝典型年大气水汽输送  

Water Vapour Transport During Two Wet/Drought Summers over the Yangtze River Valley

作　　者：高国栋[1] 翟盘茂[2] 

机构地区：[1]南京大学大气科学系,南京210008 [2]国家气象中心,北京100081

出　　处：《水科学进展》1993年第1期10-16,共7页Advances in Water Science

摘　　要：利用我国125个探空站一日两次自地面至100hpa共11个层次上的观测资料,对长江流域典型夏涝年(1980年)和夏旱年(1985年)我国大气中水汽总输送场、涡动输送场及散度场进行了计算分析。结果表明:当水汽总输送场从西北、西南和东南三支气流携带的水汽交汇于长江流域,且整个水汽输送场稳定持久,则在水汽辐合带附近导致大量降水,形成洪涝;反之,当三支气流微弱不稳定,不能形成水汽辐合带条件,则形成干旱。涡动输送亦反映出类似的特征。稳定且强盛的西南气流水汽输送是形成降水的主要条件和原因。Based on the radiosonde data observed two times a day for 125 stations in China, the total transport, eddy transport and divergence fields of water vapour are calculated and analyzed for the whole atmospheric layer over the Yangze River Valley during two typical wet/drough summers (1980/1985), when there were three currents that carried water vapour steadily from the southwest, northwest and southeast respectively, and then joined together over the Yangtze River Valley, high precipitation would appear near a convergence belt, yielding floods and water-loggings. On the other hand, during drought period, the three currents are weak and unstable, so that the condition of convergence belt formation cannot be met. Eddy transport also has similar feature. Water vapour transport due to a strong and stable current from the southwest, is a main source of precipitation.

关 键 词：干旱 洪涝 长江流域 大气 水气输送 

分 类 号：P434.5[天文地球—大气科学及气象学]