Water scarcity, data scarcity and the Budyko curve—An application in the Lower Jordan River Basin

Lower Jordan River Basin, Eastern Mediterranean Water scarcity and data scarcity are two of the main challenges for water management in the study region, therefore, all possible information should be extracted from existing data. In this context, the Budyko framework offers possibilities not yet sufficiently explored for evaluating the water-energy balance and estimating water availabilities. In this study, we applied a parametric Budyko type equation to the Lower Jordan River basin and compared data from global products, output of the hydrological model TRAIN-ZIN as well as values from literature. The curve shape parameters of the Budyko type curve fitted on different temporal and spatial scales were used to estimate renewable water resources with publicly available data for three subbasins. The adjusted Budyko curves illustrate the influence of non-climatic factors such as vegetation or soil storage on the water-energy balance and a related relatively low efficiency of evapotranspiration, despite a high evaporative demand. Renewable water resources were estimated as 25 to 30% of precipitation in average in most cases and were more strongly affected by inter-annual variabilities than by the variance between the different derived Budyko curves.