СКЛАДОВІ РАДІАЦІЙНОГО РЕЖИМУ СОНЯЧНОЇ РАДІАЦІЇ ПРИ ПОСУХАХ ЗА 1991-2020 РР. В УКРАЇНІ

Abstract

Changes in the components of the radiation regime of solar radiation during periods of intense droughts and their comparison with average values for 1991-2020 in Ukraine are given. Drought is a complex and dangerous natural phenomenon caused by the anticyclonic nature of the atmospheric circulation, the long-term transformation of slow-moving air masses over large areas. A complex of dynamic processes leads to its development. They are facilitated by an increased supply of short-wave radiation, high air temperature, a rainless period, and a lack of moisture in the air and soil. The archive of measurements of the meteorological and actinometric network of observations of the Borys Sreznevskiy CGO of the SES of Ukraine was used. A database of observations of individual components of the radiation regime of solar radiation and a catalog of droughts has been created. Droughts of different intensity and duration during the growing seasons for 1991-2020 were determined. The change in atmospheric circulation led to an increase in clear and cloudless weather, changes in the arrival of components of the radiation regime of solar radiation to the substratum. The biggest changes were in the warm period. In 1991-2020, relative to 1961-1990, the duration of sunshine, direct and total solar radiation increased during the year, and diffuse radiation decreased. During 1991-2020, droughts were observed for 22 years, including 17 growing seasons throughout the territory. They differed in types (air, air-ground, ground), duration, distribution. Prerequisites for the development of droughts were observed in some cold periods. In particular, droughts. observed in November, February-March. In the warm period, intense droughts were observed for short periods of time (less than a month) in some areas and powerful, long-lasting ones in the prevailing area. In certain months of the growing season during droughts, significant deviations of individual components of solar radiation compared to the average for 1991-2020 were observed throughout the country. Usually, during dry periods, the duration of sunshine and direct solar radiation increased significantly, diffuse radiation decreased, so the total radiation did not always increase. An increase in individual components of the radiation regime led to an increase in the total radiation balance and albedo of the underlying surface. The research is part of the monitoring of climate anomalies. They are necessary for solving applied problems of adapting agricultural production to permanent and long-term droughts in a large area.