1. Evaluation of climate change impacts on urban flooding using high-resolution rainfall data
- Author
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H. Amaguchi, J. Olsson, A. Kawamura, and Y. Imamura
- Subjects
Environmental sciences ,GE1-350 ,Geology ,QE1-996.5 - Abstract
Evaluation of the effects of climate change on urban river flow has traditionally depended on design rainfall data due to the scarcity of other data sources. However, high-resolution precipitation data, both temporally and spatially, have become accessible from regional climate models. Despite this availability, few studies have tapped into such high-resolution data to analyze urban river flow systems. This study incorporates an event-based storm runoff and inundation simulation with data from a regional climate model. This model offers a spatial resolution of 5 km and a temporal resolution of 10 min for both current and projected future climate scenarios. Rainfall analysis reveals that the 20-year probability of an hourly rainfall of 75 mm, specific to Tokyo, decreases to around 13 years for the period 2016–2035 and further to approximately 8 years for 2076–2095. This trend indicates a growing frequency of heavy rainfall events. Moreover, flood discharge analysis shows an increased downstream flow during such rainfall events if reservoir capacities remain unchanged. Flood risk assessment underscores a significant threat: areas inundated to depths of 25 cm or more may increase by 1.25 times for 2016–2035 and by 1.55 times for the period 2076–2095 when compared to current conditions.
- Published
- 2024
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