Generating improved calibrated global Sea Surface Salinity fields over a 10-year period (2010-2020) from all available satellite L-band radiometer measurements
Sea Surface Salinity (SSS) is an Essential Climate Variable (ECV) that plays a fundamental role in the density-driven global ocean circulation, the water cycle and climate.
The satellite SSS observation from the Soil Moisture and Ocean Salinity (SMOS), Aquarius, and Soil Moisture Active Passive (SMAP) missions have provided an unprecedented opportunity to map SSS over the global ocean since 2010 at 40-150km scale with a revisit every 2 to 3 days. This observation capability has no historic precedent and has brought new findings concerning the monitoring of SSS variations related with climate variability such as El Niño-Southern Oscillation, Indian Ocean Dipole, and Madden-Julian Oscillation, and the linkages of the ocean with different elements of the water cycle such as evaporation and precipitation and continental runoff. It has enhanced the understanding of various ocean processes such as tropical instability waves, Rossby waves, mesoscale eddies and related salt transport, salinity fronts, hurricane haline wake, river plume variability, cross-shelf exchanges. There is also an emerging use of satellite SSS to study ocean biogeochemistry, e.g. linked to air-sea CO2 fluxes.
Following the success of the initial oceanographic studies implementing this new variable, the European Space Agency (ESA) funded a new Climate Change Initiative (CCI) Sea Surface Salinity (SSS) project (2018-2020). The CCI+SSS project (2018-2020) aims to generate improved calibrated global SSS fields over a 10 year period (2010-2019) from all available satellite L-band radiometer measurements, extended at regional scale to 2002-2019 from C-band radiometer measurements. It will fully exploit the ESA/Earth explorer SMOS mission complemented with SMAP and AQUARIUS satellite missions. The project gathers teams involved in earth observation remote sensing, in the validation of satellite data and in climate variability study.
CCI SSS will provide data products that are specifically adapted to climate applications (i.e. include information on accuracy and uncertainty within the data). Furthermore, this project will explore the need to improve the performance of current SSS algorithm retrievals and directly contribute to climate science studies submitted to the next International Panel on Climate Change (IPCC) Annual Review for climate change in 2020.
Frequently Asked Questions
What is SSS?
SSS stands for Sea Surface Salinity. For more information please refer to the Useful Links section above.
Where can I find SSS data?
Links to data provided by this project can be found in the Data section above. Alternative data sources can be found in the Related Links section.
What is CCI?
CCI stands for the Climate Change Initiative. The CCI is a programme initiated by ESA. For more information please refer to the CCI homepage
What is ECV?
ECV stands for Essential Climate Variable. For more information please refer to the ECV Inventory page.
What is ESA?
ESA stands for the European Space Agency. For more information please visit the ESA website.
What is EO?
EO stands for Earth Observation
Data
Data pertaining to the Sea Surface Salinity project is sourced by the CCI Open Data Portal and visual analysis of the data is provided through the CCI Toolbox.
Key Documents
The following documents have been published by the Sea Surface Salinity ECV project
User Requirement Document (URD) (v2.0) (25/03/2020) - Download
Product Specification Document (PSD) (v1r6) (24/04/19) - Download
Data Access Requirement Document (DARD) (v1r4) (23/04/19) - Download
Algorithm Development Plan (ADP) (v1.1) (19/12/19) - Download
Product Validation and Algorithm Selection Report (PVASR) (v1.1) (13/12/19) - Download
Algorithm Theoretical Basis Document (ATBD) (v1.3) (19/12/19) - Download
End to End Uncertainty Budget (E3UB) (v1.2) (19/12/19) - Download
Product Validation Plan (PVP) (v1.1) (04/12/19) - Download
Systems Requirement Document (SRD) (v1.1) (06/12/19) - Download
Systems Specification Document (SSD) (v1.1) (05/12/19) - Download
System Verification Report (SVR) (v1.1) (11/12/19) - Download
Product User Guide (PUG) (v1.2) (05/03/20) - Download
Archived documentation
User Requirement Document (URD)
- v1r4 (03/01/19) -Download
Team
The Sea Surface Salinity_cci project team is made up of nine scientific and industrial partners from the UK, France, Spain, Germany and Luxembourg.
The following companies make up this consortium CCI+SSS Phase 2 (2022-2025):
- ARGANS Ltd (United Kingdom)
- Laboratoire d'Océanographie et du Climat (LOCEAN) (France)
- Laboratoire d'Océanographie Physique et Spatiale (LOPS) (France)
- Institut français de recherche pour l'exploitation de la mer (IFREMER) (France)
- ACRI-ST (France)
- AdwäisEO (Luxemburg)
- Ocean Scope (France) (Spain)
- National Oceanography Centre (NOC) (United Kingdom)
- Laboratoire d'Etudes en Géophysique et Océanographie Spatiales (LEGOS) (France)
- MetOffice (United Kingdom)
- Mercator Ocean (France)
With additional support from the following external partners:
Contacts
Key contacts within the Sea Surface Salinity project.
Project Leaders:
- Scientific Leaders: Jacqueline Boutin and Nicolas Reul.
- Project Manager: Rafael J. Catany (rcatany@argans.co.uk).
ESA Technical Officers:
- Susanne Mecklenburg and Roberto Sabia (roberto.sabia@esa.int).
Related links
The following links relate to the Sea Surface Salinity project.
- ESA Sea Surface Salinity Climate Change Initiative (Sea_Surface_Salinity_cci): Version 3.2 data collection (in the CEDA Archive)
- New maps of salinity reveal the impacts of climate variability on oceans
Websites related to ESA’s SMOS mission:
- SMOS ESA EO Mission
- ARGANS SMOS [Level 2]
- Centre Aval de Traitement des Données SMOS (CATDS) [Level 3+]
- Barcelona Expert Center (BES) [Level 3+]
- SMOS Pilot-Mission Exploitation Platform (PiMEP) ** CCI Salinity Validation reports
Website related to NASA’s Aquarius, SMAP and SPURS missions:
Publications
Published CCI Salinity related work
V. P. Akhil, J. Vialard et al. (2020), "Bay of Bengal Sea surface salinity variability using a decade of improved SMOS re-processing," Remote Sensing of Environment, vol. 248, p. 111964, 2020, doi: https://doi.org/10.1016/j.rse.2020.111964
Popp, T., et al. (2020), Consistency of satellite climate data records for Earth system monitoring , Bull. Amer. Meteor. Soc., https://doi.org/10.1175/BAMS-D-19-0127.1
Reul, N. et al. (2020), Sea Surface Salinity estimates from Spaceborne L-band radiometers: an overview of the first decade of observation (2010-2019), RSE, vol. 242, 2020, doi: https://doi.org/10.1016/j.rse.2020.111769.
Boutin, J., J.L. Vergely, E. Dinnat, P. Waldteufel, F. D’Amico, N. Reul, A. Supply, C. Thouvenin-Masson (2020), Correcting Sea Surface Temperature Spurious Effects in Salinity Retrieved From Spaceborne L-Band Radiometer Measurements, IEEE Transactions on Geoscience and Remote Sensing, 1-14, doi: 10.1109/TGRS.2020.3030488
Boutin, J., N. Reul, J. Koehler, A. Martin, R. Catany, S. Guimbard, F. Rouffi, et al. (2021), Satellite-Based Sea Surface Salinity Designed for Ocean and Climate Studies, Journal of Geophysical Research: Oceans, 126(11), e2021JC017676, doi:https://doi.org/10.1029/2021JC017676.
Gibert, F., Boutin, J., Dierking, W., Granados, A., Li, Y., Makhoul, E., . ... Zhang, X. (2021). Results of the Dragon 4 Project on New Ocean Remote Sensing Data for Operational Applications. Remote Sensing, 13(14). doi:10.3390/rs13142847
Olivier, L., Reverdin, G., Hasson, A. & Boutin, J. (2020). Tropical instability waves in the atlantic ocean: Investigating the relative role of sea surface salinity and temperature from 2010 to 2018. Journal of Geophysical Research: Oceans, 125, e2020JC016641. https://doi.org/10.1029/2020JC016641
Stammer, D., M. S. Martins, J. Köhler, and A. Köhl (2021), How well do we know ocean salinity and its changes?, Progress in Oceanography, 190, 102478, doi:https://doi.org/10.1016/j.pocean.2020.102478
Reverdin, G., Olivier, L., Foltz, G. R., Speich, S., Karstensen, J., Horstmann, J., et al. (2021). Formation and evolution of a freshwater plume in the northwestern tropical Atlantic in February 2020. Journal of Geophysical Research: Oceans, 126, e2020JC016981. https://doi.org/10.1029/2020JC016981
News and events
Latest news & events
2022 CMUG Integration & Climate Change Initiative colocation
ESA's climate research community to meet on 24-27th October 2022
Learn moreGEO Work Programme 2023-2025 released for consultation
Comments on the Summary document (version 1) welcomed by 1 August
Learn moreThe role of Systematic observations in the Global Stocktake
A side event at the UNFCCC Bonn Climate Conference highlights key report
Learn moreNew ITT: EO Science Strategy Foundation Study
Bidders meeting planned for 9 June and proposals are invited
Learn moreClimate Day at ESA's Living Planet Symposium
It is climate day on Wednesday 25 May. Here is a run down of the key climate plenary and agora sessions
Learn moreESA to host new CMIP International Project Office
The new office will be hosted at ESA's ECSAT facility in the UK
Learn moreMOOC: Understanding Climate Change using Satellite Data
New online course develops participants' satellite climate data access and analysis skills
Learn moreYoung Graduate Trainee in Climate Change Science
New position with the ESA Climate Office
Learn moreResearch fellowship: Exploiting Earth observation for climate research
New internal position within the ESA Climate Office
Learn moreSpace Climate Observatory - deep dive with Susanne Mecklenburg
One-to-one with Susanne Mecklenburg and SCO
Learn moreCCI research features in interactive Climate Change Kit
Launched at COP26, new climate guide highlights value of satellite climate observations
Learn more11th CCI Colocation meeting 2021
ESA's climate community will gather virtually 4-8th October 2021
Learn more