Keywords: radiation mode, solar radiation, droughts during the cold period

Drought is a dangerous natural phenomenon that has often been observed during the last thirty years. In certain months of the cold period of the year, droughts were observed at the end of autumn (November), at the end of winter and at the beginning of spring (February-March). The purpose of the work is to evaluate the changes in the components of the radiation regime of solar radiation during droughts or their prerequisites for the cold period of the year in 1991-2020 in Ukraine. During some cold periods, the prerequisites for the development of droughts were noted. The latest in the cold period of the year are droughts or the prerequisites for them, in particular some in the larger territory of Ukraine, which are caused by a special state of the atmosphere with the anticyclonic nature of the atmospheric circulation and the transformation of slow-moving air masses in large areas. According to a complex of dynamic processes that cause the development of this phenomenon, there is an increase in the duration of sunlight and short-wave radiation, which leads to an increase in air temperature during a period without rain or precipitation. In the conditions of changes in atmospheric circulation in 1990-2020 relative to 1961-1990, which led to an increase in clear and cloudless weather, deviations of individual components of the radiation regime of solar radiation were observed in certain months of the cold period. In the cold period of the last three decades, during droughts or the conditions for them, an increase in the duration of sunshine, the flow of direct and total solar radiation was observed, which was accompanied by a decrease in scattered radiation. The set of dynamic processes during droughts or the prerequisites for them leads to an increase in the energy potential of the active surface. Changes in the components of the radiation regime of solar radiation during droughts or prerequisites for them during the cold period of the year and their comparison relative to the average values for the years 1991-2020 in Ukraine are given. The conducted studies are important in the direction of monitoring climate change anomalies, which determine the solution of applied problems of adaptation of agricultural production in conditions of droughts or prerequisites for them during the cold period.

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