Ocean Dynamics 
Ô Springer 
Table 2 List of physical parameters, spatial coverage, and start of delivery (5 m mean) of data, provided by the partners for the MME 
Institute, Model Version 
MME Output 
SST SSS 
SSC 
TRA 
Region 
Start of delivery (5 m) 
BSH, CMOD v4 
X 
X 
X 
X 
North Sea 
Baltic Sea 
01.2013 
BSH, HBM v4 
X 
X 
X 
X 
North Sea 
Baltic Sea 
02.2013 
DMI, DKSS2013 
X 
X 
X 
North Sea 
Baltic Sea 
12.2013 
DMI, HBM v4 
X 
X 
X 
X 
Baltic Sea 
02.2013 
FCOO, GETM v6 
X 
X 
X 
X 
North Sea 
Baltic Sea 
01.2013 
FMI, HBM v2 - HIRLAM 
X 
X 
X 
Baltic Sea 
04.2014 
FMI, HBM v2 - ECMWF 
X 
X 
X 
Baltic Sea 
04.2014 
Met Office, FOAM_AMM v7 
X 
X 
X 
X 
North Sea 
01.2013 
MET Norway, ROMS v3.5 
X 
X 
X 
North Sea 
02.2014 
MSI, HIROMB v4.5 
X 
X 
X 
Baltic Sea 
04.2013 
RBINS, OPTOS_NOS vl 
X 
X 
X 
North Sea 
04.2013 
SMHI, HIROMB v4.6 NS03 
X 
X 
X 
North Sea 
Baltic Sea 
09.2014 
SMHI, HIROMB v4.6 BS01 
X 
X 
X 
Baltic Sea 
09.2014 
The spatio-temporal statistics are calculated for different study periods defined in Sect. 2.3 
were included later (see Table 2). MMEs are produced sepa 
rately for four physical parameters: sea surface temperature 
(SST), sea surface salinity (SSS), sea surface currents (SSC), 
and water transport (TRA). For SST, SSS, and SSC, hourly 
model results for 48-h forecasts have been used, starting from 
forecast time step at 01 h (Fig. 1). Since the thickness of the 
surface layer differs in space and time within the models and 
among the models, due to different vertical coordinate sys 
tems, it was suggested to provide a 5-m mean of the upper 
model layers for SST, SSS, and SSC. In this way, the data sets 
are better comparable and a compromise is made between 
optimal and available vertical resolution. The exchange of 
daily water transport through a series of transects in the North 
Sea and the Baltic Sea started earlier in the NOOS and BOOS 
communities and is used for the MME. The calculation of 
daily TRA is described in Sect. 2.2.3. 
Model forecasts of the parameters are supplied daily on the 
local ftp servers of each partner. The data sets provided by the 
individual partners for the MME are listed in Table 2. For each 
region, all forecasts are interpolated on common reference 
grids, which are defined by the nominal MyOcean products. 
The domain of the MME for the North Sea therefore ranges 
from 4.11° W/48.60 0 N to 13.00° E/60.33 0 N. For the Baltic 
Sea, the MME products cover the area from 9.04° E/53.03 0 N 
to 30.29° E/65.88 0 N. At present, the resolution is 1/9° latitude 
and 1/15° longitude for the North Sea and 1/20° latitudex 1/12° 
longitude for the Baltic Sea. Slightly different further process 
ing procedures are applied for each parameter, described in 
detail in the following subchapters. The hourly MME outputs 
are produced each day for the 48-h forecast period using all data 
available on that day. Erroneous data, i.e., with shorter forecast 
length or obvious errors in model results such as incorrectly 
interpolated SSC, are excluded from the MME. The daily out 
put of each MME includes figures, published on the NOOS and 
BOOS websites, and NetCDF files of SST, SSS, and SSC 
MME, which are freely available on the BSF1 ftp server. 
2.2.1 Sea surface temperature and salinity 
Currently, there are up to eight different forecasts of SST and 
SSS available for the North Sea and ten for the Baltic Sea. The 
most covered region in the North Sea is the central part of the 
Fig. 1 Schematic illustration 
showing the general structure of 
the participating community and 
the production and outputs of the 
MME