Projected changes in seasonal patterns of evaporation and potential evapotranspiration in Ukraine based on regional climate models of Euro-CORDEX project

The paper is dedicated to the evaluation of changes in evaporation and potential evapotranspiration rates over the territory of Ukraine by the middle and the end of the 21st century. The research was conducted based on historical (1991–2020) ERA5 data and modelled output from six regional climate models (RCMs) with 0.11°×0.11° resolution of Euro–CORDEX experiment for RCP2.6, RCP4.5 and RCP8.5 for 2021–2050 and 2071–2100. The purpose of research is to investigate possible changes of the outgoing part of the hydrological cycle across the four multiannual calendar seasons relative to the climate normal. During the near future 2021–2050 most shifts in evaporation are expected in winter with increase of 10–20% with the highest variability in the Carpathians and will exacerbate for 2071–2100. In contrast, higher rates in the potential evapotranspiration rates are found by the mid-century for summer and autumn under RCP2.6 and spring under RCP8.5 in the Carpathians for 2071–2100. While the ratio between evaporation and potential evapotranspiration generally demonstrates a steady spatial distribution, a notable exception occurs under RCP8.5 for 2071–2100. During this period, an expanded area with a ratio of 0.4–0.6 for the summer season indicated an increasing gap between available soil moisture and atmospheric demand.