GIS supported calculations of 137Cs deposition in Sweden based on precipitation data

137Cs deposition maps were made using Kriging interpolation in a Geographical Information System (GIS). Quarterly values of 137Cs deposition density per unit precipitation (Bq/m2/mm) at three reference sites and quarterly precipitation at 62 weather stations distributed over Sweden were used in the calculations of Nuclear Weapons Fallout (NWF). The deposition density of 137Cs, resulting from the Chernobyl accident, was calculated for western Sweden using precipitation data from 46 stations. The lowest levels of NWF 137Cs deposition density were noted in the northeastern and eastern Sweden and the highest levels in the western parts of Sweden. The Chernobyl 137Cs deposition density is highest along the coast in the selected area and the lowest in the southeastern part and along the middle. The sum of the calculated deposition density from NWF and Chernobyl in western Sweden was compared to accumulated activities in soil samples at 27 locations. Comparisons between the predicted values of this study show a good agreement with measured values