The project assessed the impacts of climate change on water resources in Northern Greece on a regional basis (catchment scale). The study area was the Aliakmon river basin including three sub-basins of hydrological interest located in Northern Greece. A monthly conceptual water balance model was calibrated for each sub-basin separately, using historical hydro-meteorological data. This model was applied to estimate runoff values at the outlet of each sub-basin under different climate change scenarios. Two equilibrium scenarios (UKHI, CCC) referring to years 2020, 2050 and 2100 and one transient scenario (UKTR) referring to years 2032 and 2080 were implied. It was found that reduction of the mean annual runoff and mean winter runoff values, serious reduction of the summer runoff values, as well, would occur in all cases and basins. However, the runoff values for November, December and January were increased, whereas the spring runoff values were decreased, leading to a shifting of the wet period towards December and severe prolongation of the dry period. Moreover the results indicated that all sub-basins exhibit almost the same behaviour under different climate change scenarios, while the equilibrium scenarios (UKHI, CCC) seem to give more reasonable and consistent results than the transient scenario (UKTR).
Additionally the project dealt with the climate change impacts on some critical water management issues, such as reservoir storage and hydroelectric production. Two equilibrium scenarios (UKHI, CCC) referring to years 2020, 2050 and 2100 and one transient scenario (UKTR) referring to years 2032 and 2080 were applied to represent both “greenhouse” warming and induced changes in precipitation and potential evapotranspiration. By using these scenarios, the sensitivity of the risk associated with the annual hydroelectric energy production of a large multipurpose reservoir in northern Greece has been evaluated under conditions of altered runoff.