MERCATOR OCEAN JOURNA: 
SEPTEMBER 2021 
EM 
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= > 
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ar 
50 N 
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igure &: Example of the daily L3S over the Baltic Sea (SST_BAL_SST_L3S_NRT_OBSERVATIONS_010_032 
A new L4 SST reprocessed product has been produced 
and made available in late 2020. The product is similar to 
the operational product in terms of spatial coverage and 
-esolutions and daily fields were available from 1982 to 
2019. The L4 reanalysis was created by using infrared 
satellite products for SST from Copernicus Climate 
Change Service (C3S), ESA Climate Change Initiative (CCl) 
and high-resolution sea ice products from the Swedish 
Meteorological and Hydrological Institute and Finnish 
Meteorological Institute. 
1.4 European sea products 
During the 2015-2021 period, the European Seas (EUR) 
production unit focused on the creation of new products 
and the integration of the new SLSTR sensor from both 
Sentinel-3A and 3B satellites. Additionally. three new 
sensors were added to L3 EUR NRT products: VIIRS, 
SLSTR-A and SLSTR-B. 
The ingestion of these new sensors has improved the 
Juality of products and, in particular, the mono-sensor 
L3S super-collated product (covering European Seas with 
a 1/50° resolution and generated from the merging of 
various satellite SST L2P data) (Figure 6). 
The new daily L4 NRT product, based on the super-collatea 
product, has been also impacted by the integration of these 
sensors (Figure 6). This new product has been an optimally 
interpolated gap-free (level 4) multi-sensor SST product 
ver European Seas at 1/50° resolution. This product has 
been built using the EUR L3S product derived from bias- 
zorrected European Seas L3C mono-sensor products. This 
analysis has used the analysis of the previous dav as first 
Juess field