Publications

Non-tidal ocean dynamics acting on a wide range of time-scales are imprinted on various geodetic observables including time-variable gravity changes, variations in the Earth’s rotation, and changes in sea-level. Independent numerical model estimates, ideally available with short latency, are frequently required to validate, process or interpret those measurements. While OMCT is routinely used to de-aliase short-term non-tidal ocean mass variability in the GRACE gravity field processing for some years now, we here present an updated model version. This configuration is discretized on regular 1 degree grid with 20 vertical layers, has a time-stepping of 20 min and includes various numerical adjustments that led to an improved mean circulation. As before, OMCT forcing fields consist of wind stress, surface pressure, 2mtemperatures and freshwater fluxes obtained from ECMWF’s numerical weather prediction and re-analysis models. Here, variability of an OMCT simulation forced by 6-hourly ECMWF operational analyses that form the basis of the new GRACE AOD product RL05 will be evaluated against data from in-situ ocean bottom pressure and satellite altimetry in order to demonstrate recently achieved improvements with respect to the previously available data series from OMCT.

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Dobslaw, H.; Thomas, M.; Bergmann, I.; Esselborn, S.; Flechtner, F.; Zenner, L. (2012): OMCT - New time-series for oceanic mass, angular momentum and sea level variability. General Assembly European Geosciences Union (Vienna, Austria 2012).