ABSTRACT Compared to spatial resolution, few studies have investigated the impacts of temporal rainfall resolution on hydrological modelling. Respectively using 9 years of daily and hourly rainfall data at 24 stations, we have established daily and hourly rainfall Soil and Water Assessment Tool (SWAT) models in a large-sized river basin in East Central China. Our results suggest that temporal rainfall resolution could significantly affect SWAT daily streamflow simulation results, with the hourly rainfall model performing considerably better than the daily rainfall model. One possible reason is that the hourly rainfall model could more effectively capture the impacts of rainfall in previous days, especially those with heavy rainfall and longer rainfall hours. Meanwhile, its enhanced variable storage coefficient method may lead to better streamflow routing. Furthermore, comparison of simulation results across all sub-basins has revealed a distinct scale effect in the impact of temporal rainfall resolution on SWAT simulation performance.

中文翻译：

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时间降雨分辨率对大型流域日流量模拟的影响

摘要 与空间分辨率相比，很少有研究调查时间降雨分辨率对水文建模的影响。分别利用24个站点9年的日、小时降雨数据，建立了华东某大型流域的日、小时降雨Soil and Water Assessment Tool (SWAT)模型。我们的结果表明，时间降雨分辨率会显着影响 SWAT 日流量模拟结果，每小时降雨模型的性能明显优于日降雨模型。一个可能的原因是每小时降雨模型可以更有效地捕捉前几天降雨的影响，特别是那些降雨量大且降雨时间更长的日子。同时，其增强的可变存储系数方法可能会导致更好的水流路由。此外，所有子流域模拟结果的比较揭示了时间降雨分辨率对 SWAT 模拟性能影响的明显尺度效应。