Обоснование развития гидрологических процессов с использованием динамико-стохастического подхода

Abstract

A technique has been developed for the probabilistic assessment (forecast) of the hydrological characteristic of the annual water inflow W (t) of the river basin Volga in the formation zone near the city of Volgograd. The proposed method makes it possible to build a predictive supply function that characterizes changes in the future regime of river flow in a given river section. The forecast of river water with a given availability makes it possible to effectively vary the operating modes of the water management systems of the river basin depending on the expected water content. To study the development of hydrological processes in a river basin, it is recommended to use the dynamic-stochastic concept, based on the condition that, along with the stochastic component, river runoff fluctuations also have a deterministic component, which manifests itself in the form of monotonically directed or periodic trends. As the analysis showed, long-term changes in the water content of the Volga River near the city of Volgograd do not fully comply with the laws of fluctuations of random variables. Some parameters of this process (average long-term values) change quite signifi cantly over time, other characteristics (dispersion, asymmetric distribution of members), on the contrary, change very little over time and can practically be considered constant. To construct predictive supply curves, two interrelated tasks are solved, including, firstly, the construction of functional equations of the average annual value (norm) of infl ow over time and, based on the obtained dependencies, extrapolations of the inflow rate for the first half of the 21st century are carried out and, secondly, using three-parameter gamma distribution of S.N. Kritsky and M.F. Menkel and with known predictive norms obtained in the corresponding samples and ratios CS = 2CV, ensembles of predictive probability curves for the Volga River tributary in the formation zone near the city of Volgograd are constructed.