A three‐dimensional coupled model of the western Black Sea plankton dynamics: Seasonal variability and comparison to SeaWiFS data

Abstract

[1] The main physical and biological processes that control the seasonal cycle of the plankton dynamics over the Western Black Sea were explored by means of a three-dimensional, 7-compartment, on-line coupled biophysical model that was developed for this study. Adopting high frequency forcing in terms of air-sea interaction and Danube river inputs, we performed a simulation of the coupled model during the 2002-2003 period. A series of 8-day Chl-a SeaWiFS images provided a validation tool that guided us, along with available in situ measurements, to the improvement of model parameterizations and the calibration of the biological parameters. The simulation of the seasonal phytoplankton variability over the entire Western Black Sea, extending from the highly eutrophic river influenced area to the open sea area, was a major challenge that made necessary the representation of both the spatial and time variability of several processes. Despite the model simplicity, the simulated Chl-a patterns presented a good agreement as compared to the SeaWiFS and in situ data. During winter, phytoplankton in coastal areas was shown to be limited by light availability, primarily due to the increased particulate matter concentrations, as a result of resuspension from the sediment and the increased river loads. During summer, the primary production was mostly sustained by riverine nutrients and regeneration processes and thus was strongly linked to the evolution of the Danube plume. The limiting nutrients showed deviations from the observed concentrations, indicating the necessity for a more realistic phytoplankton growth model.

Influence of Mississippi River induced circulation on the Deepwater Horizon oil spill transport

“…Examples include those from estuaries/bays such as the Delaware [ Münchow and Garvine , ], the Chesapeake [ Boicourt , ], the Columbia [ Hickey et al ., ; Horner‐Devine et al ., ], and the Niagara [ Masse and Murthy , ; Horner‐Devine , ], and from low‐salinity bands that result from multirivers, such as in the Southeast U.S. Continental Shelf [ Blanton et al ., ; Kourafalou et al ., ]. In addition, an “upstream” coastal current also develops [ Kourafalou et al ., ; Matano and Palma , ], which is particularly pronounced in delta discharges [ Kourafalou , ; Tsiaras et al ., ; Karageorgis et al ., ]. The buoyant outflow is subject to a variety of factors that can change the “typical” circulation pattern.…”

Responses of the ocean planktonic ecosystem to finite‐amplitude perturbations

“…This model was developed by Edwards [] following Steele and Henderson []. Similar models have frequently been coupled to a variety of physical models to reproduce a realistic planktonic ecosystem in some marine regions [e.g., Chen et al ., ; Olascoaga et al ., ; Ji et al ., ; Tsiaras et al ., ].…”

Developments in Earth observation for the assessment and monitoring of inland, transitional, coastal and shelf-sea waters

“…The Danube system encompasses a complex mosaic of river channels, lakes and lagoons, discharging suspended particles tens of kilometres into the coastal and sea-shelf waters of the Black Sea (Guettler et al 2013) and influence the biogeochemical properties of the shelfsea system (Friedrich et al, 2014) and has impacts as far as the Turkish coast (Tsiaras et al, 2008). The sheer size of the system and scarcity of in situ data means that remote sensing data are likely to become increasingly important for providing synoptic observations on the state of the system and its evolution over time.…”

“…( Barale et al, 2002), chl-a (Tsiaras et al, 2008) and particle size (Karageorgis et al, 2014). insights into the relative importance of hydrodynamic and meteorological processes in shaping sediment transport through the system.…”