The impact of climate change on hydrology
The Saône and Doubs watershed is a strategic territory. It is characterized by a rich diversity of water uses and sensitive aquatic environments. Against a backdrop of climate change, this region is exposed to numerous climatic phenomena. These phenomena can include flooding and prolonged drought, putting pressure on water resources.
The Établissement Public Territorial du Bassin (EPTB) Saône et Doubs has initiated a prospective study. The aim is to analyze the impact of climate change on water resources and propose sustainable adaptation strategies for the future. The study is based on a rigorous procedure designed to provide a clear vision of the challenges ahead. This study of the impact of climate change on hydrology integrates the climatic, hydrological and socio-economic dimensions specific to this basin.
The objective of this study
The main objective is to quantify the impacts of climate change on hydrology and water uses. This is to be achieved while identifying the necessary adaptation strategies. The study addresses several key issues:
- Understand the past and present dynamics of water resources.
- Provide detailed climate and hydrological projections for 2035, 2050 and 2070.
- Identify the vulnerability of aquatic environments and uses to anticipated changes.
- Propose concrete solutions for sustainable and resilient resource management.
The study follows a structured process, organized in several phases to ensure a complete and targeted analysis.
Phase 1: Assessment of knowledge and division into sectors
This first stage in the impact of climate change on hydrology is based on the collection and synthesis of existing data. These include data on climatology, hydrology and water use in the basin. Previous studies, technical reports and local data are integrated to provide a comprehensive overview. The division of the territory into coherent geographical sectors is a key component of this phase. This enables us to take into account local particularities.integrated to draw up an exhaustive inventory.
These areas include those regularly affected by flooding. They also include areas where groundwater is essential. Last but not least, they include areas with a high level of agricultural activity. This step highlights the priorities and critical points to be addressed in subsequent phases. This is achieved by combining this segmentation with a detailed cartographic analysis.
Phase 2: Retrospective analysis of climate change parameters
This phase examines the evolution of past climatic and hydrological conditions. This stage is essential for understanding the trends influencing water resources and uses. The main parameters studied include :
- Average and extreme flows: identification of periods of major flooding or prolonged drought.
- Precipitation trends: analysis of seasonal variations and heavy rainfall events.
- Temperatures: monitoring long-term trends to assess their impact on evaporation and the availability of water resources.
This analysis is based on reliable historical data spanning several decades.
Phase 3: Climate and water analysis
In the third step, we will analyze climate and hydrological projections from EXPLORE2. Two scenarios will be explored:
- RCP 4.5: a scenario of moderate increases in greenhouse gas emissions.
- RCP 8.5: a pessimistic scenario reflecting an increase in emissions and climate impacts.
Climate and hydrological projections are analyzed for three time horizons: 2035, 2050 and 2070. Key variables are analyzed to assess future impacts on aquatic environments and water uses. These variables may be river flows, maximum rainfall or the frequency of extreme events, for example.
Territory-specific simulations are carried out to evaluate different adaptation scenarios. For example, the results allow us to distinguish impacts depending on whether integrated resource management is implemented or not. These analyses underline the crucial importance of a well-thought-out, anticipatory management strategy to minimize the consequences of climate change.
What are the expected results and their applications?
The results will provide a solid basis for :
- Prevent hydrological risks: propose measures to reduce flooding and limit stress during low-water periods.
- Optimize water use management: balance the needs of different sectors (agriculture, navigation, industry, drinking water) while preserving ecosystems.
- Strengthen the resilience of aquatic environments: protect wetlands, watercourses and water tables against climatic disturbances.
- Guide public policy: integrate data into Schémas d’Aménagement et de Gestion des Eaux (SAGE). Water Management Territory Projects (PTGE) can also benefit from these data.
An integrated approach to sustainable management
This study is an essential step towards anticipating the impacts of climate change on the Saône and Doubs basin. This analysis provides decision-makers with concrete tools for taking action today. Indeed, by combining the analysis of historical data, future projections and detailed risk mapping, it becomes a real tool. This case study is an integral part of our water resources data service.
Based on this technical foundation, EPTB Saône et Doubs will be able to take targeted action to protect water resources, adapt infrastructures and guarantee balanced management of uses in a changing climate.