Geoscience Reference
In-Depth Information
seas or the changing ice coverage in the Arctic pose problems. Those deficiencies
are linked to the inability of the model to consider various interactions occurring
between the atmosphere, solid Earth and the oceans (Wunsch and Stammer
1997
).
•
Ocean models
: They can be divided in the same classes as the oceanic responses,
i.e. barotropic and baroclinic. Barotropic ocean models assume one density for
the whole water column and are forced only by wind and pressure. Although this
approach simplifies the ocean to a rather plain model, it has advantages in easier
parameterizations and lesser needs in computational power. The PPHA model
developed by Pacanowski, Ponte, Hirose and Ali (Hirose et al.
2001
) is such a
model.
Baroclinic models on the other hand include vertical changes and also effects
introduced by radiation, evaporation, and precipitation. The OMCT (Ocean Mod-
els for Circulation and Tides), developed for studying non-linear interactions
among tides and the general circulation, is an example for such a model (Thomas
2002
; Dobslaw and Thomas
2007
).
Acknowledgments
We greatly acknowledge Frank Flechtner for reviewing this part of the topic.
Furthermore, we would like to thank the Austrian Science Fund (FWF) for supporting project GGOS
Atmosphere (P20902) and the ECMWF for providing the meteorological data.
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