Applicability of zero-dimensional equations to forecast nonconservative components concentration in water bodies

Abstract

Abstract The presence of ongoing climate change and their increasing scale have now become apparent. Climate models provide a glimpse of the future. Disappointing forecasts pushing to develop models that would allow rapidly develop measures for adapting to unavoidable environmental conditions and to mitigate impacts, including those related to the deterioration of water quality in natural water bodies and reservoirs. The most simple and effective models for fast and fairly accurate forecasts regarding waters are the zero-dimensional models. Such models widely used in engineering practice owing to their considerable simplicity which is correct for conservative substances. At the same time, additional limits should be taken into account while forecasting water quality involving nonconservative components which could change its chemical characteristics in particular. The period during which the concentration of a substance becomes the same over the entire area of a reservoir could be considered as a time scale in which zero-dimensional equations are applicable, the average concentration of substances for the entire body of water can be considered only as of the average over some time not less than determined by the scope of consideration. The expression which is given in the paper allows identifying limits of applicability of zero-dimensional equations for a non-conservative substance concentration as a function of time scale and coefficient of non-conservativeness.