Remote sensing, geographic information systems and snowmelt runoff models - an integrated approach

Remote sensing (RS) and geographic information systems (GIS) play a fundamental role in hydrological applications. Because of the synergism between the two techniques, a combined use should be envisaged by hydrologists. It is the aim of this paper to show the capabilities of an integration of RS image processing, GIS and database management systems (DBMS) technologies in combination with hydrological models. A basic request for such an integrated system is a completely digital transfer of data between the different software modules. The merit of an integrated approach is demonstrated with the Alpine Snow Cover Analysis System (ASCAS). In addition to the image processing system, the GIS and DBMS, a hydrological model the Snowmelt Runoff Model (SRM) is implemented in ASCAS. Snow cover variations in the Swiss Alps were studied using NOAA-AVHRR data during the hydrological years of 1983/84 and 1992/93. Snow cover ablation patterns, snow-line variations and snow cover depletion were compared for the two years under investigation. Furthermore, the use of these data in snowmelt runoff modelling with SRM is shown.