Long-term monitoring of aridization in agriculture before and after climate change in Ukraine

This paper presents the results of systematic monitoring in Ukraine for manifestations of aridity according to the method of summarizing spring, summer, and autumn droughts conducted by I. Ye. Buchynskyi for 1872-1969 and authors' meteorological generalizations according to weather types (1951-1984) and clearly expressed zonal climate changes (1985-2006) and statistical and local signs of climate aridization at the meteorological station in the northern part of the Forest Steppe (“Chabany”) – 2006-2020, covering a total of 150 years of historical time. According to the spatial distribution of droughts, determined according to a unified methodology, starting from 1872 and ending in the late 1960s, the defining indicator is the gradual spatial distribution of seasonal local droughts with the recurrence of spring droughts after 2 years, summer droughts after 4 years, and autumn droughts, mainly in the south of Ukraine, after 2 years The number of moderate and large droughts since the beginning of the 20th century (11-30% of the distribution area) are typical for the summer period, and they are repeated in the south after 4-5 years. Abnormal droughts (over 50%) are inherent in large areas for every tenth year, which, starting from the last quarter of the 19th century and until the 1950s, ended with famine for the population (especially the droughts of 1891, 1921, and 1947). Subsequent droughts of 1963 and 1968 were determined by abnormal weather conditions, but without the manifestation of a food crisis, which is associated with the beginning of chemicalization and an increase in agricultural culture. Meteorological indicators of six stations in diverse natural and climatic zones for 1951-1981 and 1985-2008 indicate a zonal systematic increase in positive air temperatures with a decrease in precipitation, the deficit of which is compensated by a farming system with a moderate saturation of organic and mineral fertilizers, which have a stabilizing effect in extreme years. Since the last quarter of the 20th century, climate changes have been identified that are associated not only with the greenhouse effect, but also with a periodicity that depends on the ecliptic of the globe. Climate changes in recent decades are particularly noticeable, which is accompanied by a systematic increase in air temperature and an increase in climate aridity and requires new technical and technological solutions from humanity