Snowmelt Runoff Model Based On GIS And RS In The Urumqi River

Snowmelt Runoff Model(SRM) is one of the mian hydrological models for streamflow modelling and forecasting in snow-dominated mountain basins. In the high mountanis where topography is complex and climatic conditions are various.it is verey difficult to get variables and paramaeters needed by the snowmelt runoff model.The scientific and technological development of geograpic information system (GIS),remote sensing (RS) and global positioning system provided convenient for the large range snow detection.Snowmelt plays its important role in the utilization of water resources, snowmelt is a major source of people and livestok,industrial water in arid and semiarid inland river basin in the spring and the spring and summer, to undrestand and predict the snowmelt process’ is of great significance for the middle and lower reaches of water.In this paper the SRM is applied to simulate smowmelt runoff in Urumqi basin of Xinjiang, China.Use the MODIS(moderate-resolution imaging spectroradiometer)8day synthesis of data,the use of remote sensing data analysis、statistical analysis of hydrological and meteorological data、field testing and indoor means of computer simulation,Use the snowmelt runoff model snowmelt runoff simulated in the study area in spring from March to June2005.Discusses tne model structure and parameters of significanice on the basis of study,foucsing on the use of GIS and remote sensing data acquisition and analysis, resulting in improving the accuracy of simulating. The resultshowed that the coefficient of determination of the simulation could reach0.80,and the deviation of the runoff volumes was within-0.550.Study found that using the MODIS8,synthesis of data on snow cover monitoring can effectively reduce the impact of clouds on remote sensing images to a period of time can be effectively implemented on the ground monitoring.SRM model to survive as a factor model,points to bring the day temperature and the temperature threshold, above the critical temperature the number of degree-day factor counted as snowmelt depth,therefore,the estimates of the temperature input variables of the model accuracylarge.Estimate of the points to bring the daily temperature data,mainly by the temperature lapse rate of basic hydrological or meteorological stations measured data projected to the average elevation of each sub-band, Therefore,the temperature lapse rate of temperature interpolation work of great significance,appropriate selection is very critical parameter in improving the accuracy of the SRM model is applied.