Conclusion and recommendation

To conclude, this research provides an answer to the main research question: ‘How will climate change influence future droughts on the Loire River?’ The results indicate that droughts will occur more often and become more severe under all climate scenarios. Even under a more favourable scenario ‘SSP126’ droughts become significantly more extreme compared to historical droughts.

However, the results of ‘SSP126’ show that climate change measures do mitigate future droughts compared to the climate scenarios where less measures are applied (‘SSP245’ and ‘SSP585’). The difference in drought duration between ‘SSP245’ and ‘SSP585’ is minimal. This can be explained by seasonal precipitation patterns in the Loire basin, as winter months appear to act as a natural reset, replenishing water levels and preventing droughts from extending indefinitely. For deficit, ‘SSP585’ droughts will only become more extreme under higher return periods compared to ‘SSP245’. However, only one ensemble member for CMIP6 is used to predict future droughts due to a limited research period. This results in increased uncertainty regarding the predicted drought results. For future research it is recommended to explore multiple ensembles to gain a better understanding of the uncertainty range for future droughts.

Additionally, only one hydrological model was considered for this research. While the HBV model provided reasonably accurate discharge data, it showed a moderate overestimation on drought duration and deficit. This may be linked to the limited calibration and validation period. Comparing multiple models could provide more insight in the application of the HBV model for this catchment. Despite these limitations, this research offers valuable insights into future drought trends in the Loire basin. Further research is recommended to assess the potential impact of future droughts on water availability for agriculture and nuclear power plants. This would help determine whether additional drought mitigation strategies are necessary to ensure water security in the basin.