Climate projections for mainland France: which dataset to use in climate risk analyses?

Adapting our societies to the impacts of climate change is taking center stage. Earlier heat waves, more intense flooding... these climatic hazards have an impact on our territories and socio-economic activities. To identify the adaptation actions we need to take now, we need to know what risks we will have to adapt to. That is why every adaptation initiative starts with a risk assessment. This diagnosis is necessarily local, as the climate will be modified differently in different areas. For example, the climate will dry out around the Mediterranean, but become generally rainier in northern Europe. The climatic data provided by scientists is indispensable for assessing the extent of change. This data is therefore key to optimizing our adaptation and even construction projects. For example, when designing a new plant, the project team will need to assess the evolution of the average temperature on the site of the new plant, so as to be able to best integrate climate projections into the design of its cooling system. An increase of 2 deg. C will not have the same impact on the project as an increase of 4 deg. C. Today, several reference climate datasets exist in France, available on the DRIAS portal. We wanted to compare the results of these projections for the whole country, in order to understand the variability of results as a function of datasets. This publication describes the 'reference' climate datasets (DRIAS2020 and TRACC), provides a comparative analysis of these datasets for certain climate indicators commonly used in France, and proposes an operational conclusion for climate impact studies