Modeling Potential Water Resource Impacts of Mediterranean Tourism in a Changing Climate

Abstract

A scenario analysis was conducted to explore the impacts of climate and land-water management changes using an 89-km2 catchment near the Navarino Environmental Observatory (NEO) located in southwestern Messenia, Greece, as a regionally representative case study. Our objective was to quantify potential impacts on groundwater storage and streamflow at the catchment scale. To achieve this, the simple Thornthwaite-Mather-based hydrological model was calibrated to 3 years of available data (2009–2011) and used to explore the following: (1) impacts of climate change (specifically, IPCC’s A2 and B2 projections for 2071–2100), (2) impacts of land-water management changes associated with expansion of tourism activities (specifically, the addition of irrigated golf courses), and (3) the combined impact of both climate and land-water management changes. The model results indicated potential vulnerability of water resources to future climate change which could, for example, reduce streamflow between 33 and 97 % of current annual flows depending on the scenario considered. Future land-water management change could also reduce streamflow (under the current climate) by 3 or 5 % depending on if the change involves export of water outside the catchment. Clearly, this would be exacerbated under coupled climate changes which highlights the importance of environmental monitoring (part of the mission of the NEO) to inform management and planning in this and other Mediterranean regions.