4D-Var on bathymetric effect resolving model for estimating ocean currents in shallow seas

We investigate a variational data assimilation technique for retrieval of surface currents in shallow seas. We use a physically based image model consisting of shallow-water equations, which include the effects and source terms obtained from the bathymetry. These terms are included because they can be important with respect to the characteristics of currents in shallow sea regions. In order to retrieve the currents from the model, a sequence of passive tracer information must be assimilated into the model with a four-dimensional variational (4D-Var) data assimilation technique. The present study attempts to investigate the effects of the major parameters used in the proposed current retrieval scheme on the results as well as the scheme performance. The results obtained by investigating two problems are discussed and analyzed in order to obtain essential information on how to use the scheme to successfully retrieve currents from a sequence of satellite images.