Hydroeconomic Modelling of Groundwater Under Climate Change: An Application to Mahdia Ksour Essef Aquifer (Tunisia)

The Mediterranean basin is one of the world’s most vulnerable regions to climate change. The fast rise of temperatures and the decrease of precipitation are some of climate change issues. Aquifers’ recharge will be also decreased in the next century. Hydroeconomic modelling is a suitable tool to analyse the effects of climate change on the future state of groundwater resources at regional scales. Hydroeconomic models of Mahdia Ksour Essef coastal aquifer, Tunisia, were developed to show how climate change affects the groundwater scarcity and farmers’ profits. The models contain hydrological and economic parameters. Six scenarios covering three policies (no cooperation between farmers, partial cooperation regime and full cooperation regime) and two situations (normal conditions and climate change situations) are evaluated. The simulation results show the potential impacts of climate change scenarios on the aquifer water table level, groundwater extractions, crops superficies and famers’ benefits for each policy in the future. The full cooperation regime gives the best results in terms of aquifer sustainability and social welfare mainly under the climate change conditions.