The Change Tendency of Short-term Rainfall Characteristics and The Possible Measures in Urban Drainage Systems

近年来，短时暴雨频繁袭击城市，不仅给居民财产造成重大损失，也给人民生命安全造成重大损失。造成破坏的主要原因被认为是由于城市排水系统能力不足和全球变暖导致的气候系统变化。在全球气候变暖的背景下，城市排水系统的短期降雨特征将发生怎样的变化，这对城市排水系统的规划和管理至关重要，因为城市排水系统的流域面积通常比河流小得多，而且洪水到来的时间特别短。根据长期降雨记录，确定了全球变暖可能引起的短期降雨强度的变化。然后根据识别出的雨情变化的影响，根据短期雨强的评价结果生成设计暴雨，讨论了提高城市排水系统能力的可能措施的选择标准和选择过程。

Recent years, short-term storms have struck urban areas frequently and caused heavy damages not only on residents' property but also human lives. The main reasons that caused the damages have been considered due to the insufficient capacities of urban drainage systems and the changes in climate system caused by the global warming. It is crucial to urban drainage system planning and management how the short-term rainfall characteristics will change with the global warming going on because urban drainage systems usually have much small basin areas in comparison with rivers, and the flood arrival time is especially short.This study has focused on the evaluation of the impacts of the changes in short-term rainfall intensity on urban drainage systems. The possible changes in short-term rainfall intensity due to global warming have been identified based on the long-term rainfall records. The design storms then are created from the evaluation result about the short-term rainfall intensity In correspondence to the impacts of the changed rainfall situation identified, the selection standard and selection process of the possible measures has been discussed to improve the capability of unban drainage systems.