Impact of Climate Change on Salinization of Coastal Water Resources

A density-dependent numerical model was set up to quantify the actual and future (2050) salinization of a coastal aquifer in the Po Delta (Italy). SEAWAT 4.0 was used for this purpose, while PEST was used for automatic inverse parameter calibration. The use of high-resolution multi-level sampling allowed obtaining insights in the salinity stratification within the aquifer and on the vertical fluxes induced by the reclamation drainage network. The calibrated model was employed to build up a scenario investigating the effects of the projected relative sea level rise on groundwater salinity by 2050. This scenario allowed to identify the zones that resulted more affected by the relative sea level rise and to quantify the increase in salinization of groundwater, the salt loads export towards surface waters and the changing volumes of freshwater. Results show that the Po Delta will experience a significant salinization by 2050 and that the major cause is autonomous salinization via seepage of saline groundwater rather than enhanced seawater intrusion due to sea level rise.