1998—2020年三峡库区最大1h降水的时空变化特征

以年、月最大1 h降水强度及其发生时间为指标，采用趋势检验、周期分析、经验正交函数和降水过程综合强度评估方法，分析了1998—2020年三峡库区最大1 h降水的时空变化特征。结果表明：库区年最大1 h降水发生时间有每隔约10 a前移至汛前的现象，主汛期7月最大1 h降水强度有8 a的循环周期；与2010年以前比，2010年后的库区强降水落区表现出自上游向坝址迁移的走势；若最大1 h降水强度相近，则降水持续时间长、覆盖范围广的降水过程，综合强度更高，对防洪安全影响更大。

Temporal and spatial variations of maximum one-hour precipitation in the Three Gorges Reservoir Region from 1998 to 2020

Taking the annual and monthly maximum one-hour precipitation intensity and its occurrence time as indexes, the temporal and spatial variation characteristics of the maximum one-hour precipitation in the Three Gorges Reservoir (TGRR) from 1998 to 2020 were explored by using the trend test, period analysis, empirical orthogonal function and comprehensive intensity assessment of precipitation process. The results show that the occurrence time of the maximum one-hour precipitation in the reservoir area moves to the pre-flood period every 10 years, and the maximum one-hour precipitation intensity in the main flood season in July has an 8-year cycle. Compared with that before 2010, the heavy precipitation area in the reservoir area shows a trend of migration from the upstream to the dam site after 2010. The maximum precipitation intensity of one hour is close, but the precipitation process with long duration and wide coverage has higher comprehensive intensity and has more impact on flood control safety.