SPATIAL AND TEMPORAL DYNAMICS OF CHANGES IN RELATIVE HUMIDITY IN THE VOLYN REGION
Authors:   Lesya Ukrainka Volyn National University, Pavlovska Tetiana , Stelmakh Valentyna ,   Lesya Ukrainka Volyn National University
Published: February 2025

Threats related to climate change are becoming increasingly intense, frequent, and complex. The main manifestations of these changes include rising air temperatures, increased frequency of certain atmospheric phenomena, and altered precipitation patterns, which have drawn the attention of many researchers. However, changes in relative air humidity often remain insufficiently studied. The purpose of this paper is to examine the annual regime, multi-year (1977−2020) dynamics, and spatial distribution of average annual, monthly, and seasonal values of relative air humidity in the Volyn region. To achieve this goal, the following tasks were defined: to review the history of foreign and domestic research on climate change, particularly focusing on the dynamics of relative air humidity in the context of global warming; to analyze the annual patterns of relative air humidity; to investigate the seasonal regime and spatio-temporal dynamics of relative air humidity in the Volyn region; to identify trends in changes in average annual and monthly relative air humidity at weather stations in the region during 1977−2020; to analyze spatial differences in relative humidity indicators in the Volyn region during different months of the year. Methodology. The study employed methods of induction, deduction, synthesis, comparative analysis, and mathematical-statistical and graphical techniques (using Microsoft Excel 2019). Cartographic modeling was performed using GS Surfer. Statistical significance of trends in average annual and monthly relative humidity series was assessed by evaluating correlation coefficients (R), based on the ratio R/σR ≥ β. At the 5% significance level or 95% confidence interval, 𝛽=2. The research results indicate that the average annual relative humidity in the Volyn region during 1977−2020 was 78.5%, with a gradual decrease over time (the linear trend is statistically significant). Relative humidity is highest in November and December (87%) and lowest in April and May (70%). Among the seasons, winter exhibits the highest relative air humidity (85%), while spring shows the lowest (72%). During the studied period, a notable decline in relative air humidity was observed in summer and spring. Monthly analysis revealed decreasing trends in relative humidity in March, April, June, July, August, and September at all weather stations, while increasing trends were noted in November and December. The main trends in relative humidity changes in the Volyn region are: decreasing average annual and monthly values of relative humidity from March to September and increasing values in November and December; increasing relative air humidity during the cold season in the northern and central parts of the region (e.g., weather stations at Svityaz, Kovel, and Lyubeshiv); decreasing relative air humidity in the southern and southeastern parts of the region (e.g., weather stations at Volodymyr, Lutsk, and Manevychi) during February–October. Value/Originality For the first time, trends in average monthly, seasonal, and annual relative humidity values were analyzed at all weather stations in the Volyn region for the period 1977−2020. This study characterizes the annual and seasonal distribution of relative air humidity and maps the spatial differences in relative air humidity values across the region during different months of the year.