The DUACS system is used to produce altimeter sea level products, listed below according to their thematic and the different services in charge of their distribution.
|Copernicus Marine Service products|
|Copernicus Climate Service products|
|Ocean Monitoring Indicators|
|CNES/AVISO+ Demonstration and pre-operational products|
The along-track (L3) and gridded (L4) products are processed over different regions and in Near Real Time (NRT) and/or Delayed Time (DT) conditions (see DUACS processing steps) as summarized in the following table. These products were previously known (see FAQ) as AVISO products and were distributed by the CNES AVISO+. They are now produced and distributed as part of the Copernicus Marine Environment Monitoring Service (CMEMS). The Sentinel-3 L3 products are processed on behalf of EUMETSAT, funded by the European Union.
The different physical variables available in both along-track (L3) and gridded (L4) products are described in the Product User Manual . More information about the along-track CMEMS assimilation products (‘phy_assim’) are available in the FAQ.
|Regions||Along Track products (L3)||Gridded products (L4)|
|Global Ocean||GLO_L3_NRT||GLO_L3_REP (phy_assim)||GLO_L4_NRT||GLO_L4_REP|
|European Seas||EUR_PHY_L3_NRT (phy_assim)||EUR_PHY_L3_REP (phy_assim)||EUR_PHY_L4_NRT||None|
Table: DUACS products distributed by CMEMS
Note that a ‘GLO_CLIMATE_L4_REP‘ product is also available, which is a redistribution of the C3S sea level product (see below).
During 2011-2017, the Sea Level project of the ESA Climate Change Initiative program has developed and produced a reprocessed altimeter sea level product focused on homogeneity and stability of the record (Quartly et al., 2017, Legeais et al., 2018). The operational production of a climate-oriented sea level product with regular temporal extensions of the time series has been taken over by the European Copernicus Climate Change Service (C3S) and are available on the Climate Data Store. Note that this product is also distributed in the CMEMS catalogue (called GLO_CLIMATE_L4_REP).
Different physical variables are available in the gridded (L4) products. They are described in the Product User Guide and Specification document.
The differences between the gridded sea level products distributed by the Copernicus Marine and Climate services are described in the FAQ.
|Global Ocean||Delayed-time L4 gridded sea surface heights and derived variables|
|Mediterranean Sea||Delayed-time L4 gridded sea surface heights and derived variables|
|Black Sea||Delayed-time L4 gridded sea surface heights and derived variables|
Table: DUACS products distributed by C3S
Ocean Monitoring Indicators (OMIs) are quality checked and consistent information allowing regular monitoring of the ocean state, variability and change.
|Ocean Monitoring Indicators||Distributor|
|The global mean sea level evolution||CMEMS OMI catalogue|
|The map of regional mean sea level trends||CMEMS OMI catalogue|
|Mean Sea Level, El Nino bulletin, Kuroshio index, Ionian circulation||CNES AVISO+|
Table: Ocean Monitoring Indicators based on DUACS altimeter sea level products.
The evolution of the global mean sea level (MSL) is a key indicator. The characteristics of the global MSL derived from the different DUACS products are described in the FAQ.
The CNES french space agency is at the origin of the DUACS system and the CNES contribute to the development and upgrade of the DUACS sea level products and distribute some added value products and pre-operational demonstration products. They are made available on the AVISO+ portal and are also available for ODATIS. All AVISO+ products are also available in the ODATIS catalogue: ODATIS is the French repository and archive of Ocean Science research data and products. It aggregates satellite and in-situ datasets from all marine science institutes from France.
|Type of Products||Characteristics||Access|
|Ocean Monitoring Indicators||Mean Sea level, El Nino bulletin, Kuroshio index, Ionian circulation||CNES AVISO+|
|Mean and Climatologies||Monthly mean maps of sea level anomalies
Seasonally mean maps of sea level anomalies
Monthly climatology maps of sea level anomalies
|Eddies atlas||Global mesoscale eddy trajectory atlas||CNES AVISO+|
|FSLE||Maps of finite size Lyapunov exponents and orientations of the associated eigenvectors||CNES AVISO+|
|Mozambique||NRT gridded sea level anomalies & geostrophic velocity anomalies,
NRT along-track sea level anomalies
Table: DUACS products distributed by CNES/AVISO+.
The CNES/CLS DUACS altimeter production system is used to produce specific regional sea level products that are of interest for specific private users (tailored along-track measurements for regional assimilation purposes, support for scientific oceanographic campaigns,…).