Assessment of water resources change of the Danube River in the XXI century under the scenario A1B using the model "climate-runoff"

Abstract

The results of calculations of possible state of water resources within The Danube River basin in the XXI century were shown. This estimation was based on the model "climate-runoff", developed in Odessa State Environmental University. As the input to model data of climate scenario A1B (model REMO) were used. Average long-term annual flow values using meteorological data (air temperature and precipitation) from the scenario for different climatic periods of  XXI century were calculated. 32 points (grid nodes) which were uniformly distributed over the catchment area of  the Danube River were studied. Projection of changes in water resources was given by comparing the calculation results in the past (before 1989) and in the future (1990-2030, 2031-2070, 2071-2100). The major trends in climatic factors of the flow formation and water resources were established. It is shown that the climatic conditions in the XXI century on the Danube River catchment is unfavorable for the formation of runoff. The positive component of the water balance (precipitation) remains unchanged and the negative component (evaporation) increases. Isolines of  norms of climatic annual flow within the whole basin were constructed. It is established that by 2030 a significant reduction of water resources will not occur; during the 2031-2070 diminution will be 17,9 %; during the 2071-2100 – 22,0 %.