Updating seasonal snowmelt estimates using snowcourse measurements

In mountainous watersheds, like those of British Columbia and northern Pakistan, rivers are mainly fed by snowmelt from winter-accumulated snowpack and glaciers. For a safe and optimal operation of reservoirs fed by these watersheds, it is important to obtain reliable estimates of the volume and time distribution of seasonal snowmelt.An iterative procedure has been developed to utilize snow course measurements to update estimates of snowfall contribution to the watershed. Consequently snowpack volume available for melting is modified and seasonal forecasts are adjusted accordingly.The updating scheme has been applied to the snowpack measured at Mount Fidelity in the Upper Columbia River Basin in British Columbia. The results showed great improvements is streamflow forecasts, particularly during the critical melting season.