Abstract: Time series of spatial distributed ambient air temperature data sets is used as the main driving variable to estimate snowmelt in temperature index models. However, extreme climatic conditions and prohibit establishment, maintenance and operation of metereological stations in the logistically challenging of catchment of Sutlej river in Nari Khorsam province of Tibetian Highlands. Remote sensing based land-surface temperature data are also not very useful for snow-covered areas. In the present study ASTER Digital Elevation Model is used for dividing the river basin area in five elevation zones. Time series of Daily maximum and minimum temperature data logged at weather station in Kaza are extrapolated to various elevation zones using the temperature lapse rate for obtaining spatially distributed temperature data sets.

Keywords: Extrapolation, Temperature, Digital Elevation Model, Rugged Tibetan Terrain, Elevation Zones, Temperature lapse Rate.