Improved Assessment of Groundwater Recharge in a Mediterranean Karst Region: Andalusia, Spain

Abstract

Karst aquifers provide a significant contribution to the drinking water supplies of many countries in Europe. Estimating their recharge rate, i.e. the fraction of precipitation that is turned into groundwater recharge, is an essential tool to assess usable groundwater water volumes. In this study, we extended a previously developed GIS-based recharge estimation method (APLIS) to take into account climate variability by adding a simple soil moisture routine whose parameters were a priori estimated with globally available FAO soil property data. We applied the new approach to a karst system in southern Spain and evaluated our results with spring discharge observations. To exemplify the prediction skills of the new method, we applied the five climate models from the Inter-Sectoral Impact Model Intercomparison Project to assess changes in recharge rates of the study site until the end of this century.