Climate change impacts on hydrological processes in a south-eastern European catchment

Abstract

The output extracted from CNRM, MPR, and ICHEC Global Circulation Models for RCP 4.5 and RCP 8.5 Representative Concentration Pathways has been used in conjunction with the SWAT model for evaluating the impacts of future climate changes on hydrological processes in a Romanian catchment (Neajlov, 3720 km2 area) in the short (2021–2050) and long term (2071–2100). During the growing season, precipitation will decrease by up to 7.5% and temperature will increase by up to 4.2 °C by 2100. For the long term (2071–2100), the decrease in soil water content (i.e., 14% under RCP 4.5 and 21.5% under RCP 8.5) and streamflow (i.e., 4.2% under RCP 4.5 and 9.7% under RCP 8.5) during the growing season will accentuate the water stress in an already water-deficient area. The snow amount will be reduced under RCP 8.5 by more than 40% for the long term, consequently impacting the streamflow temporal dynamics. In addition, our results suggest that hydrological processes in the lower portions of the catchment are more sensitive to climate change. This study is the first Romanian catchment-scale study of this nature, and its findings support the development of tailored climate adaptation strategies at local and regional scales in Romania or elsewhere.