In semi-arid regions, coastal aquifers are extremely vulnerable because of high population density and groundwater use for production activities and touristic flow. Seawater intrusion, amplified by climate change and sea level rise, causes groundwater quality degradation and salinization of agricultural soils, reducing their quality. In addition, it causes changes in coastal wetlands, altering critical functions to safeguard biodiversity. Limited knowledge of the long-term impacts of human activities also hampers the sustainable management of coastal areas. Approaches considering system-wide interactions of physical, anthropogenic, and socio-economic factors offer holistic solutions to sustainability challenges in water-scarce coastal areas. Climate change, vadose zone, surface and ground-water, and human activities are often studied individually, without investigating their multiple and non-linear interactions as inter-dependent systems. Understanding the interactions among these factors helps defining pathways to pursue sustainability of water-scarce water soil systems (defined as Water-Scarce Critical Zone or WSCZ). This project will lay foundations for an integrated analysis framework aimed to appraise the human and climate induced impacts on coastal WSCZ systems in semi-arid areas of southern Italy, California (USA), and Qatar. The proposed framework is crucial to sustain coastal economies while mitigating their long-term environmental footprints. It develops actionable knowledge on WSCZ sustainability via multi-disciplinary and integrative stakeholders' narratives, including socioeconomic components, bio-geochemical, geophysical, and hydro-geological data, vegetation-soil-atmosphere and economic modeling. The expected project's outcomes are: i) innovative and integrated assessment framework of current and future climate and socio-economic impacts on groundwater; ii) participatory scenarios development for sustainable WSCZ management, and; iii) guidelines to draw policies and incentives to enhance the long-term economic and environmental quality WSCZ.