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The paper shows the expected changes in selected climatic indices on the basis of the results of dynamic downscaling for the 2041-2070 period with regard to the 1971-2000 period in the Polish territory. Results of the EURO CORDEX simulations with a resolution of 50 km and 12.5 km and regional models HIRHAM5, RACMO22E and the RCA4 driven by EC EARTH global climate model and RCP4.5 and RCP8.5 scenarios have been used. The maps showing absolute differences in the following climatic indices: number of frost days, ice days, summer days, wet days and days with precipitation exceeding 10 and 20 mm, between the values obtained in the scenarios and the values obtained for the reference period have been analysed. All the model results show an increase in the global temperature resulting in a decrease in the number of frost and ice days and an increase in the number of summer days. The models also show an increase in the frequency of extreme precipitation. Despite general similarities between the results of the simulations, some differences are evident, mainly due to model-specific setup. [ABSTRACT FROM AUTHOR]

The article presents thermal-oxygen conditions of Lake Białe Włodawskie in the warm half-year (May-October) in the years 2012-2015. Due to its morphometric parameters, summer stratification develops in the lake. In the period analysed in the paper, the highest temperature was recorded in July 2012 (27.5°C), and the lowest at the bottom in May 2013 (4.2°C). The highest difference in temperature throughout the water column was recorded during measurements in July 2012. It amounted to 22.7°C (27.5°C at the surface and 4.8°C at the bottom). The highest mean temperature throughout the water column (determined as the mean from all of the analysed months) occurred in 2015 (9.7°C), and the lowest in 2013 (7.8°C). The highest water temperature corresponded to the highest air temperature for station Włodawa, located several kilometres north of the lake. The mean concentration of oxygen dissolved in water (as the mean from all of the analysed months) suggests that the highest value 4.7 [mgO2 · dm-3] occurred in 2012, and the lowest 3.0 [mgO2 · dm-3] in 2013. In vertical distribution, the maximum oxygen concentration amounted to 13.5 [mgO2 · dm-3] in May 2013, and the minimum value decreased to zero multiple times. Complete lack of oxygen occurred each time in August, September, and October. It appeared the earliest in June 2013 (at a depth of 26 m), and the latest in August 2015 (at a depth of 28 m). The thickest water layer without oxygen was recorded in August 2013 already at a depth of 11 m. The studied lake is prone to strong anthropopressure. Due to favourable morphometric parameters and high resistance to degradation, however, it still maintains its high recreational values, although such a state may change in the near future in the context of increasing anthropopressure and observed climatic changes. [ABSTRACT FROM AUTHOR]