Ten years of monitoring areal snowpack in the Southern Alps using NOAA-AVHRR imagery, ground measurements and hydrological data

Monitoring snow cover in alpine areas is important for the estimation of the water storage during the snowmelt season, especially in view of irrigation, hydropower production and water supply. Cost-efficiency and fine temporal resolution of images from the satellite-borne NOAA-AVHRR sensor indicate this source of information as a suitable candidate for monitoring snow cover extent. This information can also be used for validation of distributed snowmelt models. As a result of a long-term study, ten years of snow covered area depletion curves have been estimated using remote sensing in seven watersheds of size larger than 400 km(2) in the Southern Alps. Coupling of satellite imagery with detailed topographic data and some ground measurements of snowpack depth and density provides regional estimates of snow water equivalent in northern Italy, upstream of Lakes Maggiore, Come, Iseo, Idro, and Garda. The basin water equivalent estimates are compared with the values obtained from the hydrological water balance equation used in two of the selected watersheds and computed for different snowmelt seasons. Copyright (C) 1999 John Wiley & Sons, Ltd.