EFFECT OF CLIMATE CHANGE ON THE WATER REGIME OF THE VOLYN REGION RIVERS

Abstract

The problem of climate change is one of the global and long-term challenges of the 21st century and the priorities of both the international and domestic agendas. Under further climate changes, the conditions of natural moisture supply will deteriorate which will negatively affect the hydrological regime of water bodies, in particular small rivers, and further decrease of usable surface and underground water resources will occur. Therefore, regional studies of the modern climate are relevant and timely. The article analyzes the dynamics of long-term indicators regarding climatic features in Volyn which showed a change in the characteristics of the seasons in recent decades – mild and gloomy winter, with frequent thaws and little precipitation, and hot, dry summer. As a result of prolonged thaws in the winter period, the snow cover sometimes completely melts, and the soil surface thaws as the temperature rises to 10–14° C. A slight reduction in the amount of annual precipitation was observed. This leads to some redistribution of the intra-annual runoff, with the spring flood becoming less pronounced, extended in time, with no peak maximum flows. Rainfall in the summer does not contribute to the accumulation of water reserves, but only to a short-term rise in water levels in rivers. Often the values of the minimum and maximum flow of rivers practically do not differ in summer, which indicates the effect of climate changes on the water regime of rivers. It was determined that, generally, an increase in air temperature and a decrease in the amount of precipitation resulted in a decrease in the moisture supply in the territory and thus a decrease in the water content of rivers. Should the climate changes hold to such a trend, then these territories of the Volyn region may turn into water-scarce areas.