SPATIAL DISTRIBUTION AND PRECIPITATION REGIME IN THE VOLYN REGION

Abstract

Abstract. The article is devoted to the study of long-term dynamics, intra-annual, seasonal regime of precipitation in the Volyn region at the beginning of the 21st century (2001‒2020). The scientific research was based on the materials of the Volyn Regional Center for Hydrometeorology using mathematical-statistical, graphical, comparative-geographical methods and cartographic modeling. For the first time, the authors: 1) calculated the average long-term (2001‒2020) values of annual and monthly amounts of precipitation at the weather stations of the region; 2) the trends of multi-year fluctuations of annual and monthly amounts of precipitation are clarified; 3) the structure of intra-annual and seasonal distribution of atmospheric precipitation is determined; 4) the cyclicity and synchronicity of atmospheric precipitation fluctuations at the weather stations of the region were investigated. In the course of the research, it was found out that the most precipitation in Volyn falls at the Manevichi weather station (hereafter ‒ MS), and the least ‒ at the Lutsk and Svityaz weather stations. The largest monthly amounts of precipitation are typical for July, and the smallest ‒ for February. The most uniform annual rainfall is at the Svityaz, Lyubeshiv and Kovel weather stations, the most variable is in Lutsk. According to the seasons, the most precipitation falls in summer, the least in winter. The lion’s share of precipitation (70 %) falls in the warm period of the year. During 2001‒2020, a slightly pronounced trend towards an increase in the amount of precipitation can be observed for the Svityaz and Kovel weather stations; in Manevichy, Lyubeshov and Volodymyr there is a slight decrease in the annual amount of precipitation; in Lutsk there are no pronounced directions of changes in the amount of precipitation. In the long-term dynamics of monthly precipitation amounts, trends of increasing precipitation in December, January, May and decreasing in February, March, and April are noticeable; in summer, various vector trends are observed at the weather stations of the region; in the autumn months, the amount of precipitation increases over time at most weather stations. At the Lyubeshiv, Kovel, Svityaz, and Lutsk weather stations in 2001‒2005, a phase of precipitation decrease was observed, in 2006‒2013 (2014) ‒ an increase, in 2014 (2015)‒2020 ‒ a decrease. In Volodymyr and Manevichy, the phase of precipitation decrease was observed in 2001‒2003, during 2004‒2013 ‒ an increase, and from 2014 to 2020 ‒ a decrease in the amount of precipitation. The synchronicity and out-of-phase fluctuations of annual precipitation amounts at all weather stations are characteristic in 2005‒2006, 2007‒2011, 2014‒2015, 2017‒2019. The out-of-phase fluctuations of precipitation with other weather stations are most often manifested in the Volodymyr and Svityaz stations.