气候变化对于桥水库径流影响研究

Research on Impact of Climate Change on Runoff in Yuqiao Reservoir

为研究气候变化对于桥水库径流的影响,耦合BP神经网络构建的径流模型和国际模式比较计划第五阶段(CMIP5)中的气候模式,通过偏差校正和空间缩减(BCSD)降尺度方法预测了天津市水源地于桥水库流域的气温和降水量降尺度,选取RCP4.5和RCP8.5两种情景作为径流模型的输入,预测气候变化下于桥水库径流变化趋势。结果表明,BP神经网络径流模型收敛速度快,模拟精度高,均方误差为0.013 32,模拟的相对误差不到10%,可用于于桥水库的径流模拟;BCSD降尺度方法对该区域模拟效果较好,于桥水库未来气温和降水均呈增加趋势,径流相较基准期有7.10%、10.20%的增幅。研究成果有利于掌握不同气候情景下对于桥水库未来径流影响,亦为该地区水库环境管理提供科学依据。

To study the impact of climate change on the runoff in Yuqiao Reservoir,the runoff model constructed by coupling the BP neural network and the climate model in the fifth phase of the International Model Comparison Program(CMIP5)was used to downscale and predict the temperature and precipitation in the Yuqiao Reservoir,the water source of Tianjin,by the bias correction and spatial reduction(BCSD)downscaling method.Two scenarios,RCP4.5 and RCP8.5,were selected as inputs of the runoff model,and the trend of runoff in Yuqiao reservoir was predicted considering climate change.The results show that the BP neural network runoff model converges quickly and has high simulation accuracy,with mean square error(MSE)of 0.013 32,and the relative error of simulation is less than 10%,which can be used for runoff simulation in Yuqiao reservoir;The BCSD downscaling method has better simulation effect on the region;The future temperature and precipitation are increasing trend,and the runoff has increase amplitude of 7.10% and 10.20%compared with the base period.The model prediction shows that the future temperature and precipitation will increase,and the runoff will increase by 7.10% and 10.20% compared with the base period.The results of this study are helpful for understanding the impact of different climatic scenarios on the future runoff in Yuqiao Reservoir and provide a scientific basis for the environmental management of the reservoir in this area.