摘要
Based on improvement of a distributed hydrology-soil-vegetation model (DHSVM for short) and its application to North China,a nested regional climatic-hydrologic model system is developed by connecting DHSVM with RegCM2/China.The simulated climate scenarios,including control and 2×CO_2 outputs,are downscaled to 8 stations in Luanhe River and Sanggan River Basins to drive the hydrology model.According to simulation results,under double CO_2 scenarios,annual mean temperature and evapotranspiration will increase 2.8C and 29 mm,respectively; precipitation also increase but with different value for each basin,6 mm for Luanhe River Basin while 46 mm for Sanggan River Basin;runoff change for the two basins is different too,27 mm decrease for Luanhe River Basin while 26 mm increase for Sanggan River Basin.As a result,the runoff in future for Luanhe River Basin and Sanggan River Basin will be 74 mm and 71 mm, respectively,which is approximately a quarter of annual mean runoff(284 mm)of the whole country.Total streamflow for the two basins will decrease about 2.5×10~8m^3.All these indicate that the warm and dry trend will continue in the two river basins under double CO_2 scenarios.The nested model system,with both climatic and hydrologic prediction ability,could also be applied to other basins in China by parameter adjustment.
Based on improvement of a distributed hydrology-soil-vegetation model (DHSVM for short) and its application to North China,a nested regional climatic-hydrologic model system is developed by connecting DHSVM with RegCM2/China.The simulated climate scenarios,including control and 2×CO_2 outputs,are downscaled to 8 stations in Luanhe River and Sanggan River Basins to drive the hydrology model.According to simulation results,under double CO_2 scenarios,annual mean temperature and evapotranspiration will increase 2.8C and 29 mm,respectively; precipitation also increase but with different value for each basin,6 mm for Luanhe River Basin while 46 mm for Sanggan River Basin;runoff change for the two basins is different too,27 mm decrease for Luanhe River Basin while 26 mm increase for Sanggan River Basin.As a result,the runoff in future for Luanhe River Basin and Sanggan River Basin will be 74 mm and 71 mm, respectively,which is approximately a quarter of annual mean runoff(284 mm)of the whole country.Total streamflow for the two basins will decrease about 2.5×10~8m^3.All these indicate that the warm and dry trend will continue in the two river basins under double CO_2 scenarios.The nested model system,with both climatic and hydrologic prediction ability,could also be applied to other basins in China by parameter adjustment.
