Determination of snowmelt factor in the Himalayan region

Information on the snowmelt factor (SMF) is required for the estimation of snow and glacier melt runoff. In the present study, SMF is computed for a normal snowpack over a glacier at an altitude of about 4000 m in the Garhwal Himalayas. The effect of natural dusting on SMF is also examined. For this purpose, natural dust available at the site of the experiment was uniformly spread over the snow surface to form a 2 mm thick layer. The melt runoff from the snow blocks and air temperature at 2 m above the snow surface were observed. Mean daily SMF values for normal and dusted snow blocks were computed to be 5.94 and 6.62 mm degrees C-1 day(-1), respectively. Mean daily SMF for the dusted snow block was found to be always higher than that of the dust free snow block. Maximum hourly values of SMF for the normal and dusted snow blocks were obtained in the range of 0.583-0.632 and 0.785-0.824 mm degrees C-1 h(-1), respectively, while the minimum value was zero for all cases. Maximum hourly value of SMF occurred at about 1400 h for both blocks. A comparison of the daily SMF with information already available in the literature is presented.