The forecasting of water runoff of the Styr river for the coming years

Abstract

Formulation of the problem. The water flow of the Styr River is using for the needs of industry, agriculture and the population. Thus, forecasting the water flow of this river for the future is an important scientific and practical task. The hydrological forecasts that have a lead time of one year, two years, or a decade are not as reliable as they need to be. Now in the world this problem is not solved. Along with quantitative forecasting methods, the qualitative methods have also been developed. The method of commensurability refers to such methods. It was developed by Chinese geophysicist Weng Wen-Bo in 1984. The commensurability method supports prediction of various natural phenomena, including floods and other dangerous events. The objective of this paper is to use the Weng Wen-Bo method for long-term water flow forecasting of the Styr River at Lutsk city. Methods. The commensurability method uses the dates on which natural phenomena (earthquakes, floods, droughts, etc.) were observed. For this reason, it has been called the information method. It is characterized by simplicity of calculation, graphical visualization, the use of researcher intuition and minimum needs for input information. There are several ways of forecasting using the method of commensurability. This paper is used a method of forecasting by two-dimensional commensurability graphs. Such approach consists in the determining the commensurability values in the dates array of certain phenomena occurrence and creating a two-dimensional graph of commensurability, according to which forecasting occurs. The use of such a method allows determining the years that may be wet and dry in the near future. Results. The data of observations at the hydrological station of the Styr River - Lutsk city for the period 1923-2017 are used in the paper. The results of the study on the commensurability method show that the water flow of the river Styr in 2020-2021 should be more than the norm and in 2023-2024 - less than the norm. Scientific novelty and practical significance. In Ukraine the commensurability method was used for the first time for long-term forecasting of water flow for coming years. The estimating of the effectiveness of forecasting by the commensurability method requires an array of long-term forecasts. Therefore, the next step of the study should be to forecast of water flow on different rivers, but provided that they have the long series of observation. The results of the long-term forecasting will enable the relevant services the negative consequences of a hydrological phenomenon, such as low water flow or floods on rivers will prevent.