SR-16 : Status report on snowmelt modelling studies

Abstract

A good percentage of annual run-off of rivers in the Northern region of India, originating from Himalayas is derived from snow and glaciers. Reliable estimates of volume of water contained in snowpack and its rate of release are very much required for efficient management of water resources which includes flood forecasting, reservoir operation and design of hydraulic structures etc. Investigations to understand the snowmelt processes and snowmelt forecasting techniques are required for proper utilization of abundant water resources available in the Himalayan region.

The status of studies carried out in the Indian Himalayan basins indicates that studies on snowmelt forecasting are very limited. Efforts are being made for seasonal snowmelt forecasting in Satluj catchment using regression technique based on remote sensing information on snow cover. Some investigations on snowmelt processes and snowmelt simulations and that too in one or two basins have been made.

Recognizing the need for proper planning and management of water resources ,it is found imperative to develop simple snowmelt run-off forecasting model based on generally available data of precipitation, temperature, and snow cover area for Himalayan snowbound catchments. The snowmelt models may be evolved either based on regression approach or simulation approach. The existing snowmelt simulation models based on degree-day approach such as SSARR, UBC and SRM etc. have been developed and are being used for operational purposes such as flood forecasting ,reservoir operation and hydroelectric production, irrigation and water supply in countries like U S A , Canada , Switzerland , Sweden . Their application for snowmelt simulation on the rivers of the Himalayan region is yet to be tested. In order to achieve success with such models concerted action is required to strengthen the network of observatories in the Himalayas.