1991年6月～7月太湖及里下河地区连续暴雨过程中雨团活动分析

A Study on the Rain Storm Activity over the Tai Lake Basin and the Lixiahe Area during the Period of Sustained Torrential Rain in June￣July 1991

根据水文系统雨量站网的逐时量资料，分析１９９１年６月～７月江淮流域下游两次连续暴雨过程中太湖及里下河地区的雨团活动特征。结果表明，在太湖及里下河地区均有频繁的雨团活动，雨团以自西向东移动为主，且停滞较频繁，两地区的雨团活动特征存在一定差异。雨团降水在暴雨总量中占有较大比例，对洪涝的形成和发展有重要作用。雨团活动与中尺度切交线、辐合中心、辐合线等中尺度天气系统相配合。

Based on the hourly rainfall data set from the hydrological rainfall obser- vational network, the features of the rain storm activity over the Tai take Basin and the Lixiahe Area during two periods of sustained torrential rain in June-July 1991 are analyzed. The results show that there are frequent rain storm activities over the two areas and the regimes of the rain storm activity are different between the two areas. The rain storms move mainly eastwards with stationary sometimes. The rainfall of rain storm is a great part of the precipitation for the period of sustained torrential rain and takes an important role in the formation and development of the torrential rain flood and waterlogging. The rain storm activities relate to the mesosynoptic systems such as the mesoscale shear line, the mesoscale convergence line and the mesoscale convergence center.