[G02-4] Gravity field modelling and applications

[G02-4-06] A new OGMOC mean dynamic topography model – DTU17MDT

^○Per Knudsen¹, Ole Andersen¹, Thomas Gruber², Thomas Fecher², Nikolai Maximenko³ (1.DTU Space, Technical University of Denmark, Geodesy, 2.Institute of Astronomical and Physical Geodesy, Technical University of Munich, Germany, 3.University of Hawaii at Manoa, IPRC, Honolulu, USA)

Within the ESA supported Optimal Geoid for Modelling Ocean Circulation (OGMOC) project a new geoid model have been derived. It is based on the GOCO05C setup though the newer DTU15GRA altimetric surface gravity has been used in the combination. Subsequently the model has been augmented using the EIGEN-6C4 coefficients to d/o 2160.
The new DTU17MDT has been derived using this new geoid model and the DTU15MSS mean sea surface. Compared to other geoid models the new OGMOC geoid model has been optimized to avoid striations and orange skin like features. Finally, the filtering was re-evaluated by adjusting the quasi-gaussian filter width to optimize the fit to drifter velocities. Subsequently, the drifter velocities were integrated to enhance the resolution of the MDT. The results show that the new MDT improves the resolution of the details of the ocean circulation.