## 4 Conclusions  
The analysis of the climate indices for 49 cities makes it possible to formulate several general conclusions in relation to the predicted changes in temperature and precipitation in Poland by 2050:  
* The country's average annual temperature shows an upward tendency. A slightly higher temperature increase is expected to occur in northeast Poland. The temperature increase by 2050 is expected to be equal to approx. 1 \({}^{\circ}\)C (0.83 in RCP 4.5 and 1.2 in RCP 8.5). * The number of hot days is expected to increase, with the most significant increase in the country's north. On average, the number of hot days could increase by 3.7 days (3.0 in RCP 4.5 and 4.4 in RCP 8.5). * In both scenarios, the decrease in the number of frost days is slightly higher in the country's north. By 2050, the number of frost days could decrease by around 19 (15.3 in RCP 4.5 and 21.9 in RCP 8.5). * The number of cold days is expected to decrease throughout the country. The most significant decrease in this scenario occurs in the country's northeast. The number of cold days in the 2050 horizon could decrease on average by around 8 days (8 in RCP 4.5 and 8.6 in RCP 8.5) compared to 2010. * The annual precipitation increases mainly in cities in the eastern part of Poland. The smallest increase is expected in locations in the western part of the country, where it could be below 5%. By 2050, the annual precipitation is expected to increase by an average of 40 mm in RCP 4.5 to 80 mm in RCP 8.5. * A slight increase, by approx. 3.3 days (2.1 in RCP 4.5 and 4.5 in RCP 8.5) is the total number of days with precipitation expected. * Both RCP scenarios predict an increase in the number of days with extreme precipitation, mainly in eastern Poland, for approximately 2 days (1.4 in RCP 4.5 and 2.7 in RCP 8.5). Figure 10: Variability in (**a**) annual precipitation sum, (**b**) number of days with precipitation (PR \(>\) 1 mm/day), (**c**) and number of days with extreme precipitation (PR \(>\) 10 mm/day) for 49 cities in Poland based on the results of the statistical correction of the EURO-CORDEX model ensemble for the 2010 horizon, the 2030 horizon, the 2050 horizon, and the observations from weather stations for the 2010 horizon. The horizontal line in the boxplot corresponds to the median, and the ranges represent the 1 st and 3 rd quartiles, respectively. An increase in the average annual temperature results in an increase in the number of hot days and a decrease in the number of cold days. As a result of the rising temperatures in the cold season, the number of frosty days is expected to decrease. The most significant changes, both in summer and winter, occur in the northeast of Poland. The increase in annual precipitation is due to the increase in the number of extreme precipitation days. The total number of days with precipitation could increase slightly. The changes in precipitation are expected to be the smallest in the western part of the country. Conceptualization, [PERSON] and J.W.K. ; Data curation, M.J.; Formal analysis, M.J.; Funding acquisition, J.S. ; Investigation, M.J. and J.S. ; Methodology, M.J. and J.S. ; Project administration, J.S. ; Resources, M.J., J.S. and J.W.K. ; Software, M.J.; Supervision, [PERSON]; Validation, M.J.; Visualization, M.J.; Writing--original draft, J.S. ; Writing--review and editing, M.J. and J.W.K. All authors have read and agreed to the published version of the manuscript. This research was a part of the MPA44 project funded in the scope of the Cohesion Fund, Operational Programme Infrastructure and Environment 2014-2020. Not applicable. The data presented in this study are available on request from the corresponding author. The data are not publicly available due to privacy. The analyses were accomplished in the frame of two projects: ClimCities (\"Climate change adaptation in small and medium size Cities\") and MPA (\"Developing climate change adaptation plans for cities with more than 100,000 inhabitants\", [http://44 mpa.pl/](http://44 mpa.pl/)).