On small oceanic islands such as the Azores, water resource management plans increasingly need to incorporate the effects of global climate change to accurately predict future water supplies for populations and agricultural activities, particularly farming.
The expected changes in temperature and precipitation on the Azores islands have important implications for all components of the island's hydrological cycle, altering the amount of evapotranspiration, surface runoff and infiltration into groundwater systems.
Groundwater is the only source of water supply on the Azores islands, with around 236,413 inhabitants (2021 census), 1,000,000 tourists per year and 2,000 km from the mainland, without the capacity to import large quantities of freshwater. The exploited aquifers are of the perched type, with a low storage capacity and flows with large seasonal variations, and basal with salinization problems due to marine intrusion.
This article discusses some effects of climate change on the groundwater of this island, especially in the basal aquifer, the likely main source of freshwater in the future on this island.