In this case study the the dynamic of river plumes in a tideless and wind forced estuary of the Baltic Sea we investigated. The main effords were paid to the Pomeranian Bight and especially the Oder river which is the main source of fresh water in the western Baltic. Due to the buffering of river discharge in the Stettin lagoon the pulslike inflow of fresh water into the Pomeranian Bight produced well separated plumes. The structure of the plumes is mainly controlled by geostrophical adjustment and the water exchange regime between the Lagoon and the Bight, whereas the direction of the plume propagation depends on the wind forced coastal dynamic.
CTD- and ADCP-measurements were carried out in the Pomeranian Bight during the TRUMP-Expeditions from 1993 to 1996. Basically differences were observed in the development of river plumes for westerly and easterly wind forcing. The freshwater was transported in a small stripe at the polish coast with westerly winds. During east wind situations stable plumes were established in the western part of the Bight. With the estimation of geostrophical current components from the observed density field the ADCP-current measurements were splitted in wind- and density driven currents. The influence of topographical features was described.
Also numerical modelations with a 3D-hydrodynamical model were carried out for typical forcing conditions and they were compared with the observations.