HYDROLOGY UNDER CLIMATE CHANGE IN A TEMPORARY RIVER SYSTEM

The three different future scenarios showed an increase in mean temperature for all months between 0.5-2.4°C and a reduction in precipitation (by 4-7%) for the period 2030-2059 (MPI, KNMI, SMHI). The results of the present work show that climate change will bring a reduction of water resource availability and some alterations in the hydrological regime. The SWAT model, which proved to be a valuable operational tool for evaluating the potential impact of climate change on water resources, estimates a reduction of total water yield and a shift of the flow regime towards drier conditions, although the river type classification will probably remain essentially unvaried. A sever reduction of snowfall in the mountainous part of the basin was also estimated that is expected to impact the flow regime. However, it is important to take into account that several sources of uncertainties, which depend both on the used hydrological models and on the climate change scenarios, affect the predictions of the hydrological response of a river basin under climate change. In addition, some of the assumptions made (i.e. that land use does not change in the future) could be incorrect as climate change could also result in a significant alteration of land cover. Hence, we have to consider projections not as a predictive method, but as a tool that may be used to assess changes in process dynamics.