Analysis Of The Impact Of Climate Change On Runoff In The Shule River Basin

Shule River Basin belongs to the typical climate change sensitive area.The ecological environment there is extremely fragile. In recent years, with the change of climate and the intensification of human activities, a lot of problems of ecological environment problems in the Shule River Basin have appeared.To carry out the research on climate change in the future in Shule River Basin, is of great significance for strengthening the rational utilization of water resources and ecological environment protection. Therefore, this study tries to predict climate change over this basin.Using meteorological data from 6 weather stations together with river discharge from 3 hydrological gauges, it analyzes the variation of temperature, precipitation and runoff during observed period. The MKtrend test and MK catastrophe point test result shows that the average and maximum temperature arisessignificantly at 0.05 level. Temperature mutation point occurred in the 1980 s and 1990 s, while precipitation mutation point was not significant.The runoff of Changmabao hydrological station in all seasons increased significantly, the summer runoff in other two station increased significantly and the spring runoff decreased significantly.It uses SDSM(statistical downscaling model)based on observation data of 6 meteorological stations and the output of NCEP to downscale the meteorological data. The results show that the Nash coefficient is all above 0.98 for air temperature simulation.The simulated precipitation is overall higher than the observed.Then, the distributed hydrological model has been established in Shule River, based on the underlying surface data and historical weather data. It finds that the high resolution satellite rainfall can better simulate the runoff trend than the observed rainfall in 6 meteorological stations.This paper uses SDSM to get meteorological data in the climate scenarios A2、B2 during 2022~2038, and use hydrological model to get the CMB station runoff in future climate scenarios. The result shows that the average monthly runoff during 2022 to 2038 may be about 15m3/s higher than simulated runoff in 2000~2005.The runoff in summer and autumn will decrease year by year, while the runoff in winter and spring isjustthe reverse.