An integrated Hydrological Model for Assessing Climate Change Impacts on Water Resources of the Upper Po River Basin

Climate change can have profound impacts on water availability. In order to assess the impacts on water resources in complex Alpine river basins, an integrated model that can simulate mutual interactions between natural hydrological processes and anthropogenic disturbances is required. The objective of this study is to show the potential of such an integrated approach in quantifying the impacts of climate change on water resources availability in the Upper Po river basin in Italy. Results show that in the time slice 2041–2050 summer river discharge is expected to decrease with respect to 2001–2010, due to a substantial decrease of seasonal precipitation and an accelerated snow melt that causes an earlier snow depletion. Glaciers volume is expected to decrease to half the current value in 2025, while the minimum elevation of the lowest point of the glaciers is expected to increase from 1890 m asl to about 2850 m asl. It is shown that this change can affect regulation of large artificial reservoirs at higher elevation that are mainly dependent on glacier melt for their supply. Increase of annual precipitation is expected to increase groundwater detention that can be used as supplement to diminished river discharge during summer.