基于Hadgem2_ES的气候变化对金华江流域枯水变化的影响评估

气候变化引发降雨径流等水文要素的变化已经成为学界的共识,浙江省内近年来频发的气候极端事件更是引起众多学者的重视。枯水水文作为水文学的一部分,分析其变化有其积极的实际意义。选取了金华江流域1975-2004年的日降水、温度和径流资料,使用多站统计降尺度方法,基于最新CMIP5中的Hadgem2_ES模型,利用GR4J水文模型模拟了未来(2071-2100年)的径流,重点分析了几个重要枯水指数7Q10和30Q10的变化。结果表明,未来这两个指数都有明显的上升趋势,即气候变化可能缓和金华江流域未来的枯水情况。

Hadgem2_ES-based Impact of Climate Change on Low Flow of the Jinhua River Basin

It is a common view that climate change has influenced hydrological elements such as precipitation, temperature and river flow. Zhejiang Province has witnessed the climate extremes with high frequency in recent years and it has drawn a lot attention of hydrologists. Low flow hydrology is a very important part of hydrology. It is quite meaningful to analyze the low flow. The historical daily precipitation, temperature and flow in 1975-2004 in the Jinhua River Basin are used as baseline data in this study. Climate projections from Hadgem2_ES of CMIP5 for 2070-2100 are downscaled to station scale projections based on a multi site statistical downscaling model GIST. The flows in future period are generated by a lumped hydrological model GR4J. Two typical low flow indices 7Q10 and 30Q10 are calculated and compared. The results show that the two indices have obvious rising trends, implying a better situation in low flow periods under climate change.