Impact of combining GRACE and GOCE gravity data on ocean circulation estimates

• Main Authors: Janjic Pfander, Tijana, Schröter, Jens, Savcenko, R., Bosch, W., Albertella, A., Rummel, R., Klatt, Olaf
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 2011
• Subjects: Southern Ocean
• Online Access: https://epic.awi.de/id/eprint/24592/; https://doi.org/10.5194/osd-8-1535-2011; https://hdl.handle.net/10013/epic.39481

In this work we examine the impact of assimilation of multi-mission-altimeter data and the GRACE/GOCE gravity fields into the finite element ocean model (FEOM), with the focus on the Southern Ocean circulation. In order to do so, we use the geodetic approach for obtaining the dynamical ocean topography (DOT), that combines the multi-mission-altimeter data and the GRACE/GOCE gravity fields, and requires that both fields be spectrally consistent. The spectral consistency is achieved by filtering of the sea surface height and the geoid using profile approach. Combining the GRACE and GOCE data, a considerably shorter filter length resolving more DOT details can be used. In order to specify the spectrally consistent geodetic DOT we applied the Jekeli-Wahr filter corresponding to 241 km, 121 km, 97 km and 81 km halfwidths for the GRACE/GOCE based gravity field model GOCO01S and to the sea surface. More realistic features of the ocean assimilation were obtained in the Weddel gyre area due to increased resolution of the data fields, particularly for temperature field at the 800 m depth compared to Argo data.