Running a Model#
Applications#
Flooding#
Thirza van Esch:
Climate change is expected to increase precipitation in the Northern Hemisphere, affecting river discharge and flood risk. This study evaluates its impact on the Wien River and potential flooding of the adjacent U4 subway line using the HBV model with CMIP6 climate data.
The flood threshold for the U4 line is set at 530 m³/s. Observational data indicates a current return period of 641 years. Under the sustainability-focused SSP119 scenario, this increases slightly to 697 years, while the four other SSP scenarios reduce it to 191–272 years—indicating more frequent extreme discharge events.
Since the current return period is already below the 1000-year design threshold, four out of five scenarios suggest increased flood risk for the U4 line. However, uncertainties remain due to limited observational data (∼40 years) and the use of only one of 25 MPI model ensemble members. Future research should incorporate all ensemble members and assess current flood protection measures for potential upgrades.
Droughts#
Ischa Hollemans:
This study examines the impact of climate change on drought characteristics in the Loire River basin, focusing on changes in drought duration and severity. Using the HBV model and CMIP6 (MPI-ESM1-2-HR) data, future droughts were projected under three climate scenarios: SSP126 (low emissions), SSP245 (moderate emissions), and SSP585 (high emissions).
Droughts were defined using a critical flow threshold of 66.5 m³/s at Blois-sur-Loire. An algorithm was developed to calculate drought duration and deficit, and the HBV model was calibrated accordingly.
Results show a clear increase in drought frequency and severity across all scenarios, even under SSP126. While mitigation under SSP126 reduces drought impacts, SSP585 projects the most extreme deficits. Differences in drought duration between SSP245 and SSP585 are small, likely due to winter flow recovery.
Uncertainty remains due to reliance on a single ensemble member. Future work should incorporate more ensemble members and explore implications for regional water management.