Evaluation and Monitoring of Snowcover Water Resources in Carpathian Basins Using Geographic Information and Satellite Data

The paper describes the working methods developed in the Remote Sensing Lab of the National Institute of Meteorology and Hydrology in Bucharest and the obtained results for: basin snowcover areal extent and snowline elevation determination, new snowfalls identification, melting zones discrimination, snowpack water volume determination, snowcover depletion curves, etc. The method for evaluation the water resources stored in the snowpack is based on the use of data from three investigation levels: satellite, air and ground. This approach is required by: the complex physiographical peculiarities of the Carpathian watershed; the necessity of determining both the extent of the snowcover and its condition; the instability in time, during the winter-spring season, of the maximum stored amount, and the snowmelt process beginning which requires a continuous surveillance of the snowcover; the need to correlate remotely sensed data with the ground truth. A complex related geo-referenced database, consisting of high and medium resolution satellite data (NOAA-AVHRR, TERRAMODIS, LANDSAT-TM, SPOT-XS), terrain information derived from Digital Elevation Models (DEM) and other exogenous data (maps and ground measurements) was designed and implemented on PC-based computing systems. The GIS developed for the snowcover water resources management includes information referring to the topography, land vegetation cover, land use, soil type, hydro-meteorological parameters, that could be used as separate layers or interconnected in order to extract the necessary information for a correct and accurate estimation of the snowpack conditions and snowcover water resources during the winterspring period.