N/AInternational audienceThe National Karst Observation Service: for a long-term monitoring of karst aquifers in the face of new climatic extremes. Karsts constitute heterogeneous aquifers, the result of the dissolution of carbonate rocks. These aquifers are now strategic water resources for different uses. At the same time, they are very sensitive to anthropogenic pressures and ongoing climate change. To answer to this societal concern, the community of karst hydrogeologists proposed to the INSU-CNRS the establishment of a national service for the observation of karstic systems (SNO KARST). Bringing together researchers and teacher-researchers, thisstructure now makes it possible to provide the community with a database including, in part...