Estimation of Blue and Green Water Potentials of Türkiye under Global Climate Change Effects

Abstract

This study analyzed the impact of global climate change scenarios on the water resources of Turkiye by means of various climate and hydrological simulations projected for this century. An integrated approach was used by coupling regional climate models and a semi-distributed hydrologic model to assess the climate change impacts. A regional climate model, that is the output of 3 global models (HadGEM2-ES, MPI-ESM-MR and CNRM-CM5.1), has been conducted with RCP4.5 & RCP8.5 emission scenarios for whole the country at the watershed-scale with a resolution of 10x10 km. Hydrological simulations were conducted by using the Soil and Water Assessment Tool (SWAT) Model to determine the variation of surface and groundwater resources based on climate change projections. Blue water flow (water yield + deep aquifer recharges), green water storage (soil water), and water surplus/deficit projections have been conducted considering the current and projected status for water-consuming sectors of domestic, industry, agriculture, and ecosystem services. Results attained were further evaluated through statistical methods regarding blue water flow and green water storage potential of the country. The main purpose of the study was to aid the legal authorities, and decision-makers in prioritizing the environmental measures to be taken for mitigation of climate change impacts on Turkiye in the long- run. The work was the first country-wide hydrological modelling study through globally accepted climate change scenarios.