Areal distribution of snow water equivalent evaluated by snow cover monitoring

A method is proposed to determine the areal distribution of the maximum seasonal water equivalent of snow in mountain basins. Because a sufficient density of direct measurements is not available in remote, inaccessible areas, the accumulation of snow at the start of the melting season is reconstituted. The disappearance of snow in grid units is monitored using Landsat data, the number of degree days necessary to melt the snow is totalized, and the water equivalent of the snow melted is calculated. The reconstituted water equivalent values can be used to correct precipitation measurements in winter. Together with limited point measurements these new areal data can improve the evaluation of snow reserves for seasonal discharge forecasts.