水电能源科学

针对城镇化下极端降雨频率变化问题，从空间维和时间维的角度出发，提出了以城镇化时空变化为协变量的极端降雨空间极值模型，探讨了城镇化影响下太湖流域苏锡常平原地区极端降雨频率与重现期水平变化。结果表明，在城镇化影响下，常州、无锡、苏州等城市地区极端降雨的发生频率会增加，特别是高强度极端降雨事件，常州、无锡城区以及苏州郊区极端降雨发生频率不稳定；在10～100年重现期下出现极端降雨的高值与低值的站点一致，100年重现期下考虑城镇化影响后模拟的最高、最低极端降雨值分别为336、294 mm;在各个重现期下，超过1/2站点的重现期水平在城镇化影响之后会增大；从空间变化上看，极端降雨高值区逐渐向城市中心转移。研究成果可为科学理解城镇化对极端降雨的影响提供依据。

To address the simulation of extreme rainfall frequency changes under urbanization, this study proposes a spatial extreme value model incorporating the spatiotemporal variation of urbanization as covariates. We investigate the changes in extreme rainfall frequency and return levels under the influence of urbanization in Suzhou-Wuxi-Changzhou plain in the Taihu Lake Basin. The results indicate that under the influence of urbanization, the frequency of extreme rainfall events increases in urban areas such as Changzhou, Wuxi, and Suzhou, especially for high-intensity events. In particular, extreme rainfall occurrences in urban centers of Changzhou and Wuxi and suburban areas of Suzhou exhibit higher variability. From the 10-year to the 100-year return period, the spatial distribution of extreme rainfall highs and lows remains consistent across models. Under the 100-year return period, the maximum and minimum extreme rainfall values simulated with urbanization factors are 336 mm and 294 mm, respectively. Over half of the stations exhibit increased return level estimates after accounting for urbanization. Spatially, extreme rainfall hotspots shift progressively toward urban centers. The study provides a scientific basis for better understanding the impact of urbanization on extreme rainfall.