Author(s): Javier Martinez-Dalmau; Enrique Tocados; Carlos Gutierrez-Martin; Taher Kahil; Julio Berbel

Linked Author(s): Javier Martínez Dalmau

Keywords: Hydro-economic modelling; Water management; Climate change; Drought

Abstract:

The Guad-ECHO (Guadalquivir Extended Continental-scale Hydroeconomic Optimization) model is applied to Guadalquivir Basin aimed to analyse the socio-economic impacts derived from water policy decisions (e.g., reallocation) in a context of climate change and the occurrence of drought events. Guadalquivir basin is representative of Mediterranean climate supporting a population of 4.2 million inhabitants, around 900.000 ha of irrigated land (25% of Spanish irrigation) and some biodiversity hotspots (such as Doñana Natural Park). The hydrological model estimates existing water flows and stocks in the basin under different scenarios either derived from physical changes (climate change and drought events) or institutional changes (water policy). The link with micro-economic models is determined by the availability of water and individual agents’ response. Special care is given to irrigation water use (85% of basin abstractions) and farmer’s response is simulated with mathematical programming (PMP) which is calibrated for 2020 baseline while the rest of economic sectors (urban, industry, energy, navigation) are simulated with a simpler microeconomic model. A differential feature of irrigation in Guadalquivir is the large share of deficit irrigation strategies (in 80% of basin irrigated area the crop receives water below full production requirement) and ‘modernized’ irrigation schemes (80% of area incorporates high efficiency systems). Model results illustrate impact of droughts at regional economy and sectoral levels detailing indicators for: direct and indirect employment, regional GVA, prices and GHG emissions. The model shows the effects of alternative drought management policy (water markets, current re-allocation rules, etc.). The model is developed in GAMS and follows EU Open Science Criteria including open access to data and models to citizen.    

DOI: https://doi.org/10.3850/IAHR-39WC252171192022667

Year: 2022