A Modeling tool to assess local and regional impact of climate change on crop water requirement in Euro-Mediterranean Countries, and assessment of Mediterranean irrigated agriculture vulnerability

Irrigation is a needed practice in arid and semi-arid Euro-Mediterranenan regions, where water scarcity is expected to be more severe under climate change, thus requiring optimal water management.This work develops a tool able to estimate crop water consumption and irrigation demand at local and regional scale. The Simulation of Evapotranspiration of Applied Water model was implemented in R programming language (SIMETAW_R), and validated in ten European sites through the FLUXNET network. SIMETAW_R was improved using R-GIS libraries, to build a spatial platform (SIMETAW_GIS) that can interact with large geodatasets of environmental conditions and agronomic practices, to provide simulations of future water consumption and application. The study was conducted at Euro-Mediterranean scale on economically relevant crops (maize, wheat, and grape), for past (1976-2005) and future (2036-2065) climate, under Representative Concentration Pathways scenarios 4.5 and 8.5, with a resolution of 14 km. In addition, the vulnerability of irrigation agriculture to climate changes was assessed for five Mediterranean reservoirs and associated irrigation systems.Results show an increasing future irrigation demand, which will worsen water use conflicts in Mediterranean. Although all investigated basins have a large capacity, the irrigated agriculture shows potential vulnerability to climate changes. Results may be useful to prioritize implementation of sustainable water use strategies.