GUINEHUT, S.', BUOKGIORNO NARDELLI, B.?, CHAU, T.“, CLAUSTRE, H.“, ETIENNE, H.’,
GEHLEN, M.*, GREINER, E.’, MULET, S.’', SAUZEDE, R.“, VERBRUGGE, N.’
CLS, Ramonvwille Saint-Agne, France - °CNR, Naples, Italy - °LSCE, Gif sur Yvette Cedex, France - *LOV, Villefranche-Sur-Mer, France
Complementary to ocean state estimates provided by
modelling and assimilation systems, a multi observations-
aased approach is available through the MULTI-
JBSERVATIONS (MULTIOBS) Thematic Assembly Center
(TAC) of the European Copernicus Marine Environment
Monitoring Service (CMEMS). Copernicus Marine Service
MULTIOBS TAC provides multi-observations ocean products
at global scale derived from the combination of two or
more different sensors, satellite and In situ, and using
state-of-the-art data fusion techniques. These products
cover the blue ocean for physics and the green ocean
for the carbonate system and biogeochemical variables.
MULTIOBS products are available in Near-Real-Time (NRT)
or as Multi-Year Products (MYP) for the past 25 to 35 years
with regular temporal extensions. MULTIOBS TAC provides
also associated Ocean Monitoring Indicators (OMls). It uses
mostly input from other TACs.
MULTIOBS TAC delivers 4 physical, 1 carbon and 2
biogeochemical products and 3 associated OMlIs that are
dedicated to the following:
provide global ocean state-estimates of variables still
critically poorly sampled at all scales,
take advantage of the strength of the Global Ocean
Observing System (in situ and satellite),
- stay close to the observations (i.e., unbiased),
- resolve mesoscale structures at the right place (when
eddy permitting),
provide long stable timeseries enhancing ocean
climate and ocean health monitoring capabilities.
MULTIOBS TAC was created in 2018 and has 4 main
partners: Collecte Localisation Satellites (CLS), Consiglio
Nazionale delle la Ricerche (CNR), Laboratoire des Sciences
du Climat et de l’Environnement (LSCE) and Laboratoire
d’Oceanographie de Villefrance, Institut de la Mer de
Villefrance (LOV/IMEV). However, a multi observations
component called GLO-OBS (Global Observations) existed
since the year 2015 as a sub-component of Copernicus
Marine Service Global Monitoring and Forecasting Center
‘GLO-MFC) (Le Traon et al., 2017). Most of MULTIOBS TAC
products are very recent and have been in Copernicus
Marine Service catalog for Just about 2 years. Those new
products leverage R&D from EU H2020 project and other
projects funded by space agencies (CNES and ESA)
Main achievements from 2015 to 2021 are listed in
section 1 by product. MULTIOBS TAC status at the end of
Zopernicus-1 is then described (section 2) before post
2021 perspectives (section 3).
1. MAIN ACHIEVEMENTS FROM
2015 TO 2021
1.1 5SSS/SSD
Starting in 2015, CNR developed a global 2D sea surface
salinity (SSS) and sea surface density (SSD) L4 product by
ınterpolating in situ SSS and SSD data with the
multidimensional Optimal Interpolation (Ol) technique
originally introduced by Buongiorno Nardelli (2012). This
method extracts information on surface patterns from
satellite Sea Surface Temperature (SST) L4 data, increasing
the effective resolution of interpolated fields. The technique,
originally developed to interpolate SSS, has been modified
by Droghei et al. (2016) to provide dynamically consistent
SSD field.
‘he first version of this product was provided on a 1/4°
regular grid at weekly sampling (monthly averaged fields
are also available) as a multi-year timeseries in April 2017.
In 2018, two major evolutions have been developed: first
che use of SMOS satellite fields as additional forcing, then
the processing chain adaptation to provide consistent NRT
Yelds. Continuous Improvements were then Implemented
