Assimilation of Satellite Observations of the Chlorophyll-a Concentration and the Calculated Data on the Marine Environment Dynamics in the Adaptive Model of the Ecosystem of the Black Sea Northwestern Shelf

Abstract

The model of the sea upper layer ecosystem based on the equations of the adaptive balance of causes method is proposed. The scheme of the cause-effect relations from the paper by Fasham, Ducklow and McKelvie constituting the nitrogen cycle reactions in the sea upper layer is used in the model. Parameterization of biochemical reactions of the substance interaction is substituted in this model for the normalized ratios of the substances’ average concentrations resulted from analyzing the observations of the biochemical fields of the Black Sea northwestern shelf. The satellite-derived chlorophylla concentrations as well as the data on advection and diffusion obtained from calculations of intraannual variability of the current velocity field in the sea upper sea layer using the hydrodynamic model, are used as the external influencing factors. Being regarded as the external influencing factors, the information was used for calculating the deviations of the biochemical fields’ concentrations from their average values assumed to be a stationary state of the ecosystem. The observations were assimilated through including the sources’ additional functions (representing the assimilated data) to the right parts of the adaptive ecosystem model equations. The regional maps of the biochemical fields permitting to analyze their spatial-temporal variability in 2015 were constructed. The drawn conclusion confirms utility of the proposed approach used for mapping the biochemical fields of the sea upper layer.