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为三峡工程大江截流的顺利进行和二期围堰的安全渡汛提供三峡区间降水的基本情况，利用１９６５～１９８９年三峡区间３４个雨量站逐日降水量资料，计算了单站和区间的年、月、日多年平均降水量和面雨量，分析了年降水和暴雨的地区分布及时间分布特点，初步揭示的三峡区间降水的基本特征是：三峡区间平均年面雨量为１２５０ｍｍ，是长江流域多雨区和多暴雨区之一；年降水量和暴雨的年内分配呈双峰型，前峰出现在７月，后峰出现在９月；秋季可出现量级大、持续时间长的暴雨；１１月上旬，三峡区间多年平均旬面雨深为２５．６ｍｍ，无面暴雨出现，三斗坪坝区多年平均日降水量≥１０ｍｍ的天数很少，仅为１ｄ。计算了４月、５月和６～９月的２４ｈ和３ｄ三峡区间面暴雨频率，为三峡工程二期围堰安全渡汛和施工安排提供降水方面的信息。
The basic situation of the Three Gorges section precipitation was provided for the smooth closure of the Three Gorges Project and the flood diversion for the second phase of cofferdam. Based on the daily precipitation data of 34 rainfall stations in the Three Gorges from 1965 to 1989, the annual, The average annual precipitation in the Three Gorges area is 1250 mm, which is the rainfall area in the Yangtze River Basin And heavy rainfall areas. The annual distribution of annual precipitation and storm show a bimodal pattern, the first peak appeared in July and the second peak appeared in September. The autumn heavy rainfall appeared in large magnitude and long duration. In early November In the Three Gorges area, the mean annual depth of rain over the years was 25.6 mm, with no surface rain occurring. The number of days with average annual precipitation ≥ 10 mm in Sandouping Dam was very low for only 1 day. The frequency of heavy rain events in the three and gorges section of the Three Gorges in April, May and June-September was calculated to provide information on the precipitation safety during the construction of the second phase of the Three Gorges Project cofferdam.