Die Kuste, 81 (2014), 273-290 
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5.1 Operational schedule/Computer facilities 
The latest hardware upgrade at BSH towards three IBM P7 755 servers (4x8 core, 3.6 
Ghz Power7 processors) in combination which die strongly increased computing effi 
ciency of the HBM code give a substantial speedup in die model runs compared to the 
former system. It is planned to use die free resources primarily for an improvement in 
operational schedule. The current status is that only the 2D storm surge model runs 4 
times per day based on the latest meteorological forcing. The 3D circulation model is 
only run once a day. The final stage of die planned upgrade of the operational schedule 
will allow also for 4 runs per day witii both the 3D NOKU and die 3D EL setup with a 
forecast lead time of at least 78 hours. As an intermediate step 2 runs per day are aimed 
at. Along with these changes goes an optimization of die data provision for internal and 
external customers, which will lead to a reduced delay between model run and data deliv 
ery as well as an increase in system robustness. 
5.2 Data assimilation 
All model runs carried out at BSH today are completely “free” model runs, i.e. there is no 
direct connection from model space to observational space, besides the indirect connec 
tion via the use of observational data in the boundary conditions. This lack of connection 
to observations has die strongest implication for physical processes in die ocean which 
are not directly connected to die atmospheric forcing like haline stratification. In order to 
overcome tiiis limitation, data assimilation procedures have been developed over die last 
decades, first in meteorology and later on also in ocean modelling. BSH has started to 
build up a data assimilation capacity in close cooperation with die Alfred-Wegener- 
Institute (AWI). The first step was the implementation of a data assimilation scheme for 
sea surface temperature (SST) which resulted in a substantial error reduction in tempera 
ture (LOZA et al. 2012; LOZA et al. 2014). The assimilation of satellite born SST data was 
extended towards the use of temperature and salinity profiles (LOZA et al. 2013). In the 
next steps it is planned to include furdier sources of temperature and salinity data, i.e. 
from FerryBox lines, and extend die metiiods to handle also ocean currents, sea ice and 
water level. To make die data assimilation scheme - which is in a pre-operational stage at 
the moment - fully operational demands for a furdier upgrade of computational facilities 
at BSH mentioned above. 
5.3 High resolution estuary setups 
A very high spatial resolution is needed to attain accurate forecast of currents, water level 
and other parameters in complicated coastal areas like die German North Sea estuaries. 
A first step towards high resolution forecasts was made in die development of a setup 
with 90m horizontal grid spacing for the Elbe estuary in die OPTEL project. The furdier 
development of the Elbe model became operational in die beginning of 2013. There are 
plans to extend die coverage of die high resolution setup towards die Jade/Weser and the 
Ems estuary witii spatial resolution of at least 100m.