© Author(s) 2013. CC Attribution 3.0 License GIS ANALYSIS OF AVERAGE MONTHLY SPECIFIC RUNOFF IN

Abstract: Water cycle research is the basis of any water management and one of most important elements is the runoff. In environmental analyzes the most commonly used is the annual specific runoff. Due to increasing environmental awareness the need for better seasonal runoff knowledge is crucial to support the decision making processes in order to improve the sustainable water resources management. The water quantity is crucial for all environmentally based water management. For water vulnerability analyzes the specific runoff can be taken into account as water sensitivity indicator. Since the runoff is varying in time and space the average annual runoff is not always enough, the substantial improvement can be achieved with the use of seasonal or monthly runoff. With the use of GIS we joined the results of two hydrological analyzes: water balance and river flow regimes. We used kriging to transform the point data of discharge coefficients in order to create continuous spatial distribution of the variable as a raster. To compute long-term average monthly specific runoff raster we used mathematical functions in GIS to combine the long-term specific runoff raster and the monthly discharge coefficients. The final results are 12 raster maps of monthly discharge coefficients and 12 maps of long-term monthly specific runoff