Impacts of climate change on European minimum flows under global warming of 1.5, 2, and 3 °C
- 1Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, TS, Italy (mgvaldecasas@inogs.it)
- 2Earth System Physics Section, The Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy
Drought is a recurring hazard in Europe, affecting various sectors and causing a wide range of socioeconomic and environmental consequences. Global warming is very likely to significantly alter the water cycle across Europe, with serious implications for terrestrial hydrology. As a result, hydrological droughts are expected to become more frequent and severe in this region. In this framework, this preliminary study assesses the impact of climate change on extreme river droughts for the entire European region using a large ensemble based on 44 EURO-CORDEX simulations under the business-as-usual emision scenario (RCP8.5). For this, long-term (1976-2100) daily runoff from EURO-CORDEX simulations is used to feed a river routing model derived from the CETEMPS Hydrological Model (CHyM), obtaining thus the simulated daily discharge.
To investigate how climate change may affect the magnitude of minimum flows, a block minima method is here applied using 7-day simulated minimum yearly flows for each river point during nonfrost seasons. First, minimum flows for a reference period (1995-2014) are fitted to different extreme values statistical distributions to determine which is best for adjusting the yearly minimum discharge. Then, the minimum flows at various recurrence intervals obtained from the best distribution's adjustment are used to analyze changes at +1.5, 2, and 3 °C global warming above preindustrial levels. Therefore, the purpose of this preliminary work is twofold: (1), to elucidate what is the best probability distribution to fit the annual 7-day minimum discharge in Europe and (2) to project the minimum river flow to analyze the impact of climate change on extreme river drought.
The findings of this study will provide valuable information to plan suitable adaptation and strategies to climate change from a hydrological perspective.
Keywords: Hydrological drought, EURO-CORDEX, CHyM, minimum river flow
Acknowledgments: first author is supported at present by OGS and CINECA under HPC-TRES program award number 2020-02
How to cite: García-Valdecasas Ojeda, M., Di Sante, F., and Coppola, E.: Impacts of climate change on European minimum flows under global warming of 1.5, 2, and 3 °C, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6318, https://doi.org/10.5194/egusphere-egu22-6318, 2022.
