Articles | Volume 12, issue 3
Ocean Sci., 12, 797–806, 2016
https://doi.org/10.5194/os-12-797-2016

Special issue: Operational oceanography in Europe 2014 in support of blue...

Ocean Sci., 12, 797–806, 2016
https://doi.org/10.5194/os-12-797-2016

Research article 15 Jun 2016

Research article | 15 Jun 2016

Coupling of wave and circulation models in coastal–ocean predicting systems: a case study for the German Bight

Joanna Staneva, Kathrin Wahle, Heinz Günther, and Emil Stanev Joanna Staneva et al.
  • Institute for Coastal Research, HZG, Max-Planck-Strasse 1, 21502 Geesthacht, Germany

Abstract. This study addresses the impact of coupling between wave and circulation models on the quality of coastal ocean predicting systems. This is exemplified for the German Bight and its coastal area known as the Wadden Sea. The latter is the area between the barrier islands and the coast. This topic reflects the increased interest in operational oceanography to reduce prediction errors of state estimates at coastal scales, which in many cases are due to unresolved non-linear feedback between strong currents and wind waves. In this study we present analysis of wave and hydrographic observations, as well as results of numerical simulations. A nested-grid modelling system is used to produce reliable nowcasts and short-term forecasts of ocean state variables, including waves and hydrodynamics. The database includes ADCP observations and continuous measurements from data stations. The individual and combined effects of wind, waves and tidal forcing are quantified. The performance of the forecast system is illustrated for the cases of several extreme events. The combined role of wave effects on coastal circulation and sea level are investigated by considering the wave-dependent stress and wave breaking parameterization. Also the response, which the circulation exerts on the waves, is tested for the coastal areas. The improved skill of the coupled forecasts compared to the non-coupled ones, in particular during extreme events, justifies the further enhancements of coastal operational systems by including wave effects in circulation models.

Download
Short summary
This study addresses the impact of coupling between wind wave and circulation models on the quality of coastal ocean predicting systems. This topic reflects the increased interest in operational oceanography to reduce prediction errors of state estimates at coastal scales. The improved skill of the coupled forecasts compared to the non-coupled ones, in particular during extreme events, justifies the further enhancements of coastal operational systems by including wind wave models.