Zur morphodynamischen Modellierung am Beispiel der Tideeider
(Keine Zusammenfassung in deutscher Sprache vorhanden.)
The highly dynamic morphology of the Eider estuary at the German North Sea Coast is strongly affected by a storm surge barrier at the river mouth. The operation of the five sector gates influences the estuary hydrodynamics, sediment dynamics and morphology in different scales reaching from small-scale scour evolution behind the gates, to medium scale meandering of the main river channel, to large-scale sedimentation trends of the whole estuary. In order to investigate the morphodynamic processes a 2DH process based model has been set up, covering the whole tidally influenced estuary area from the weir to a dam 36 km upstream. Hydrodynamics, sediment transports and bottom evolution have been calculated in successive modules coupled to a morphodynamic modeling system. A thorough calibration and validation of the single computational modules was carried out for short-term events, so that the model is capable to simulate short-term morphodynamic events in reasonable quality. The application of process based numerical models to medium to large scale (years to decades)events requires reduction and simplification techniques as input- and process filtering. Common techniques (e.g. representative boundary conditions) are described and discussed. A modified approach for defining a representative tide is presented. Its application to medium scale morphodynamic simulations for periods up to two years shows promising results. Results of large scale simulations are presented and discussed.