Using GIS Methods in Spatial Modelling of Climatic Water Balance Index

Abstract

The main aim of this study is to find the best spatialization method to describe spatial differentiation of climatic water balance (CWB) in Poland. Monthly mean values of air temperature and precipitation totals from 60 synoptic stations as well as monthly totals of solar radiation (23 measuring points) were taken into consideration. Source material covered period 1985-2006. Regarding the prior research as well as data availability the potential evapotranspiration data was calculated by Turc formula. CWB modelling was conducted with two methods simultaneously: simple and multiple linear regression (with latitude, altitude and distance from the coast line as variables), and map algebra. Validation proved the map algebra to be the better of the two spatialization methods. Nevertheless the obtained results proved also that except for the method local factors are of the great importance in CWB modelling especially in the mountains and at the coast. To optimize the method it is necessary to reduce the research scale using more insitu data that would enable inclusion of more local variables such as land form and land cover into the analyses.