The products processed by the Sentinel-3 Level 2P/L3 Marine Altimetry Service (CNES/CLS consortium under an EUMETSAT Contract, funded by the European Union) have been delivered as a pre-operational service on the AVISO+ dissemination since December 15th, 2016 for L2P NRT, January 17th, 2017 for L2P STC (see <link internal-link>AVISO+ web page product) and on the CMEMS <link http: marine.copernicus.eu services-portfolio access-to-products _blank external-link-new-window>Catalogue since April 19th, 2017 for L3 NRT/STC products.

The Products

These products are derived from the SRAL (dual-frequency Synthetic Aperture Radar Altimeter) instrument onboard Sentinel-3. The L2P products are mono-mission global products containing 1 Hz along-track corrected sea surface heights with respect to a mean sea surface, corrections and geophysical parameters. The last versions of altimetric standards are used and there is a homogenised format for all satellites. They are generated in Near-Real Time (NRT), Short-Time Critical (STC) and Non-Time-Critical (NTC) timeliness. They are distributed in the user friendly NetCDF format. The added value compared to level 2 products is:

• The update of geophysical standards to calculate sea level anomalies, such as
  • FES2014 ocean tide
  • CNES/CLS 2015 mean sea surface referenced to a 20 year reference period
  • Filtered ionospheric correction
  • Dynamical atmospheric correction for L2P NRT products (instead of only inverted barometer height correction in the case of L2 NRT products).
• A validity flag to remove spurious measurements
• The distribution of L2P SLA near real time products splitted in passes (instead of 10 minute granules for L2 near real time products).

The L3 Sentinel-3A products are global along-track products that contain time, sea level anomaly and absolute dynamic topography only for valid marine surfaces. The L3 products have under-gone a multi-mission cross-calibration process versus a reference mission (Jason-3). 

The dissemination

Considering the success of the pre-operational service delivery, EUMETSAT decided to begin the operational phase. Beginning on June 27th, the operational phase will imply the product’s warranty in terms of accuracy, fitness for use or purpose. 

Note also the dissemination of Non-Time-Critical (NTC) Sentinel-3A products

The L2P STC/NRT products are also available through <link http: www.eumetsat.int website home news dat_3525999.html _blank external-link-new-window>EUMETSAT dissemination via EumetCast. <link file:22947 download>             <link file:22948 download>