Ocean Dynamics 
4) Springer 
maximum of 52 layers and finest resolution of 2 m (Transition 
Area, 1 m) coarsening toward the sea bed. The thickness of the 
top layer is 8 m in general but reduced to 2 m in the Transition 
Area. The horizontal resolution of HBM is 1 NM and the 
number of vertical layers is 122, where only 25 layers are 
provided in the MyOcean product. 
GETM at FCOO The Danish Defence Centre for Operation 
al Oceanography (FCOO) runs three nested setups 
(Biichmann et al. 2011) of the General Estuarine Transport 
Model, GETM, in operational production (Burchard et al. 
2009, 2010). The three GETM setups are configured as 
one-way nesting, with differing horizontal resolutions of 
3 NM, 1 NM, and 600 m. The 1-NM North Sea-Baltic Sea 
setup and the 600-m setup, covering the Kattegat-Arkona 
region, are both baroclinic setups, which use 60 layers of 
general vertical coordinates (Flofmeister et al. 2011) with 
zooming toward surface and sea bed. The maximum thick 
nesses of the upper layers in the Skagerrak are 0.45, 0.6, 0.8, 
1.0, 1.25, and 1.42 m. Elsewhere, the thicknesses of the 
vertical layers are thinner. 
HBM at FMI The Finnish Meteorological Institute (FMI) 
uses HBM in operational mode covering the North Sea and 
Baltic Sea (Berg and Poulsen 2012; Poulsen and Berg 2012). 
The grid of the baroclinic model consists of regular horizontal 
coordinates with a 3-NM resolution and up to 50 depth layers, 
and a two-way nesting with a 0.5-NM grid, covering the Dan 
ish Straits and the Wadden Sea. The thickness of the surface 
layer is 8 m. Two separate model runs are made with different 
atmospheric forcing using European Centre for Medium- 
Range Weather Forecasts (ECMWF) and High Resolution 
Limited Area Model (HIRLAM). 
FOAM AMM at the Met Office The Met Office runs a 
coupled hydrodynamic-biogeochemical Forecasting Ocean 
Assimilation Model 7 km Atlantic Margin Model (FOAM- 
AMM) (O’Dea et al. 2012) covering the Northwest Shelf, in 
cluding Skagerrak and Kattegat, and parts of the North-East 
Atlantic. In the current model version the Little Belt, Great 
Belt, and the Sound are defined as big rivers for transition to 
the Baltic Sea. The model is run on a regular horizontal grid 
with about 7-km resolution. The vertical resolution of 32 levels 
is determined by a hybrid s-sigma terrain following coordinate 
system (following Song and Haidvogel (1994)). Sea surface 
temperature (SST) is assimilated utilizing infra-red satellite ob 
servations from the SEVIRI, NOAA-AVHRR, and METOP- 
AVHRR instruments along with in situ measurements. 
ROMS at MET Norway The Norwegian Meteorological In 
stitute (MET Norway) runs the Regional Ocean Modeling 
System (ROMS) covering the Northwest Shelf, including 
Skagerrak and Kattegat, and the Nordic Seas (Shchepetkin 
and McWilliams 2005). The model setup consists of a hori 
zontal grid with orthogonal polar-stereographic coordinates of 
4-km resolution and a vertical S-coordinate system with 35 
levels. The transition to the Baltic Sea is handled the same way 
as for FOAM AMM in the current model version of ROMS. 
Data assimilation is applied for SST using OSTIA SST anal 
ysis. For the MME, the data are interpolated to the Met Office 
FOAM AMM horizontal grid (~7 km). 
HIROMB at MSI The Marine Systems Institute (MSI) uses 
the baroclinic and eddy-resolving High-Resolution Opera 
tional Model for the Baltic Sea (HIROMB) (Funkquist and 
Kleine 2007) in operational mode for forecasts in Estonian 
marine areas, the Gulf of Finland, and the Gulf of Riga 
(HIROMB-EST). The model setup itself is configured with 
out nested grids and uses the boundary conditions of 
HIROMB-BS01, described below. The horizontal resolution 
is 0.5 NM. It uses fixed z-coordinates with a vertical resolu 
tion of 3 m from the surface down to 90-m depth and 5 m 
between 90- and 135-m depth. 
OPTOS_NOS at RBINS The Royal Belgian Institute of Nat 
ural Sciences (RBINS) runs OPTOS NOS, covering the En 
glish Channel and the southern North Sea, nested with the 
high-resolution OPTOS BCZ, covering the Belgian waters 
and its approaches from Dunkirk to Rotterdam. The model 
setup consists of a regular latitude-longitude grid with about 
6-km resolution, and a vertical sigma coordinate system 
consisting of 20 layers (Luyten et al. 1999). 
HIROMB at SMHI The Swedish Meteorological and Hydro- 
logical Institute (SMHI) runs the baroclinic model HIROMB 
(Funkquist and Kleine 2007; Axell 2013) with two different 
configurations: The NS03 grid has 3-NM horizontal resolu 
tion, covering the North Sea and Baltic Sea, and the BS01 grid 
has a horizontal resolution of 1 NM, covering only the Baltic 
Sea, Kattegat, and Skagerrak. The horizontal grid is set up on 
regular coordinates and the vertical grid consists of z-coordi 
nates. Data assimilation is applied for SST, using observations 
analyzed by the Swedish Ice Service as well as from OSI-SAF, 
near-real-time in situ temperature (T) and salinity (S) profiles 
from the Finnish research ship Aranda, real-time in situ S/T 
profiles from Swedish and German buoys, and in situ surface 
measurements of S and T from Ferry Boxes on several mer 
chant ships and ice breakers. 
2.2 MME processes and ensemble statistics 
Since April 2013, most ofthe above mentioned forecasts have 
been provided by the partners to the MME system. It is im 
portant to note that the contribution to the MME is made on 
voluntary basis. As a consequence, not all partners started to 
deliver all parameters at the same time; hence, some forecasts