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TONANI, M.'. MAKSYMCZUK., J.', GOLBECKHK. 1.2. LORKOWSNI, 1.2. LI, X.2, KAY, S.13, 
KING, R.R.', PEQUIGNET A.-C.', POLTON, J.A.“, SAULTER, A.’, SKAKALA, J., 
WAKELIN, 5.L.“, ARTIOLI, Y.”, ASCIONE, 1.', BRUCIAFERRI, D.', MCCONNELL, N.?, 
SYKES, P.', RENSHAW, R.', SIDDORN, J.** 
Met Office, Exeter, United Kingdom - “Federal Maritime and Hydrographic Agency, Hamburg, Germany 
Dlymouth Marine Laboratory, United Kingdom - “National Oceanography Centre, United Kingdom 
OVERVIEW 
The North West-European Shelf (NWS) Monitoring and 
Forecasting Centre (MFC) delivers forecast and reanalysis 
products for the European shelf seas. This region is 
characterized by shallow seas tidally dominated. The 
model domain extends into the deep part of the Atlantic 
to properly resolve the across shelf exchanges of Atlantic 
water. The model eastern boundary covers the Kattegat/ 
Skagerrak straits for getting the Baltic water Inflow 
characterized by low salinity water. 
The NWS-MFC provides ocean, wave, and biogeochemical 
forecast and reanalysis products. All the components of 
the systems have been improved during the last five years, 
considering the user's feedbacks and requirements. Wave 
products did not exist at the beginning of the project and 
have been added for both forecast and reanalysis. 
The resolution of the model was increased, from 7 to 1.5 km, 
for resolving the mesoscale and improving the resolution of 
the coastline. The wave component, added in 2017, had been 
recently coupled with the ocean, Improving the representation 
ofthe ocean momentum budget equation. The accuracy of the 
Initial conditions of all the components has been increased, 
thanks to the improvement of the data assimilation. 
More observations and new variables are now assimilated 
in both the physical and the biogeochemical models. It is of 
paramount importance to be able to understand the impact 
of these evolutions on the quality of the products delivered 
to users. Hence, all products are regularly assessed with 
classical verification metrics. New verification methods suited 
to increasingly complex and high-resolution models are being 
introduced. A new method based on spatial neighbourhood 
has been developed and applied to inter-compare the 
accuracy of forecasting products at different resolutions. 
1. MAIN ACHIEVEMENTS 
FROM 2015 TO 2021 
To provide a state-of-the-art ocean forecasting system, 
the various components are regularly upgraded, and new 
components added. 
A significant effort on R&D activities has guaranteed a 
zontinuous pull-through of improvements. Not all the R&D 
jevelopments have yet been implemented in the forecast 
and reanalysis systems but will be included in future 
avolutions of the systems. 
An overview of the major evolution of the forecast 
(named analysis_forecast in Copernicus Marine Service’s 
zatalogue) and reanalysis (or multi-year) model systems is 
described in Figure 1 and Figure 2. 
Data assimilation has been Improved, giving better 
initial conditions for both the physical (PHY) and the 
biogeochemical (BGC) components. At the beginning of 
Copernicus 1, the NWS systems assimilated only Sea- 
Surface Temperature (SST) from in-situ and satellite 
observations, using a 3D-VAR scheme NEMOVAR (Waters et 
al., 2015). Vertical profiles of temperature and salinity and 
Sea Level Anomaly have been included in the observations 
3assimilated in the PHY forecast system since March 2016 
(King et al., 2018). Assimilating SLA in a regional, shallow 
and tidally dominated model is challenging. The first 
Implementation assimilated SLA observations only where 
the model bathymetry was deeper than 700 m