OSD Ocean Science Discussions OSD Ocean Sci. Discuss. 1812-0822 Göttingen, Germany 10.5194/osd-6-1895-2009 An operational implementation of the GHER model for the Black Sea, with SST and CTD data assimilation Vandenbulcke L. 1 Capet A. 1 Beckers J. M. 1 Grégoire M. 1 Besiktepe S. 2 GeoHydrodynamics and Environment Research, Université de Liège, Belgium NATO Undersea Research Centre, La Spezia, Italy 31 08 2009 6 2 1895 1911 Copyright: © 2009 L. Vandenbulcke et al. 2009 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://os.copernicus.org/preprints/6/1895/2009/osd-6-1895-2009.html The full text article is available as a PDF file from https://os.copernicus.org/preprints/6/1895/2009/osd-6-1895-2009.pdf

In this article, we describe the first operational implementation of the GHER hydrodynamic model. This happened onboard the research vessel "Alliance", in the context of the Turkish Straits System 2008 campaign, which aimed at the real-time characterization of the Marmara Sea and (south-western) Black Sea. The model performed badly at first, mainly because of poor initial conditions. Hence, as the model includes a reduced-rank extended Kalman filter assimilation scheme, after a hindcast where sea surface temperature and temperature and salinity profiles were assimilated, the model yielded realistic forecasts. Furthermore, the time required to run a one-day simulation (about 5 min of simulation, or 10 min with pre-processing and data transfers included) is very limited and thus operational use of the model is possible.

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