CoAuthors

Ole Andersen (DTU Space, Denmark); Nikolai Maximenko (University of Hawaii at Manoa, IPRC, Honolulu, USA); Jan Hafner (University of Hawaii at Manoa, IPRC, Honolulu, USA)

Initially, a new geodetic mean dynamic topography model DTU22MDT is derived using the new DTU21MSS mean sea surface. The DTU21MSS model has been derived by including re-tracked CRYOSAT-2 altimetry also, hence, increasing its resolution. Some issues in the Polar regions have been solved too. The geoid model was derived within the ESA supported Optimal Geoid for Modelling Ocean Circulation (OGMOC) project. It was based on the GOCO05C setup, though the newer DTU15GRA altimetric surface gravity was used in the combination. The OGMOC geoid model was optimized to avoid striations and orange skin like features. Subsequently the model had been augmented using the EIGEN-6C4 coefficients to d/o 2160.
The processing scheme used for deriving the new geodetic MDT is similar to the one used for the previous geodetic DTU MDT models. The filtering was re-evaluated by adjusting the quasi-gaussian filter width to optimize the fit to drifter velocities. Subsequently, the drifter velocities are integrated to enhance the resolution of the MDT model. Weights and constraints are introduced in the inversion and tuned to obtain a smooth model with enhanced details. A special concern is devoted to the coastal areas to optimize the extrapolation towards the coast line. The presentation will focus on the coastal zone when assessing the methodology, the data and the final model DTUUH22MDT.