Water balance changes across environmental gradients in Sweden

Abstract

In this study we have analyzed long term changes in the water balance for 250 catchments in Sweden. By quantifying the spatial correlation of these changes between catchments we were able to constrain measurement uncertainty in precipitation, discharge and catchment area. This allowed us to create reliable regional estimates of changes in precipitation, discharge and evapotranspiration for the period 1960-2010. The Bodyko framework was used to translate these water balance changes to water use efficiency trajectories across environmental gradients (latitude, elevation, agriculture and population). These trajectories in Bodyko-space help to identify the contributions of climate change and changes in water use efficiency to observed changes in the water balance. We show that within Sweden distinctly different trajectories of hydrological change occur and that these differences should be accounted for in climate change adaptation strategies.