Key points are not available for this paper at this time.
Understanding the impact of climatic drivers on future catchment runoff is crucial for assessing how climate change will influence hydrological regimes. This knowledge is essential for evaluating water resources at the local and regional scales. Here, we assessed the contributions of climatic drivers to runoff changes under future conditions across Europe by analyzing the sensitivity of runoff to changes in precipitation and potential evapotranspiration using the Budyko framework. This analysis was conducted for 35,408 basins and based on ensembles of bias-adjusted climate projections and hydrological data. We further explored the link between runoff changes and catchment hydrological similarities, investigating the impact of climatic drivers on runoff across different hydrological regimes in three future periods (early, mid and late century) and emission scenarios. Results indicate precipitation as the primary driver of runoff changes across Europe under low and medium emission scenarios. However, by the mid and late century in high emission scenarios, potential evapotranspiration’s contribution becomes comparable to precipitation, significantly influencing runoff variations in central and southern Europe. Finally, the sensitivity of the runoff changes to climatic drivers is linked to the regime of the river systems. Runoff changes in basins with slow response to precipitation tended to show a more balanced contribution from both precipitation and potential evapotranspiration under high emission scenarios, while basins that are very responsive to precipitation, changes in precipitation primarily led to runoff changes. This Budyko-based diagnosis provides new insights into attribution analysis by linking hydrological regimes to runoff changes under global warming, supporting more effective local adaptation strategies.
Clemenzi et al. (Tue,) studied this question.