SSHA - Sea Surface Height Anomalies

Types of dataset: Monomission altimeter product.

Contents: along-track Sea Surface Height with respect to a Mean Sea Surface height above reference ellipsoid (CLS01 MSS for Jason-2, CNES-CLS11 MSS for Saral, CNES_CLS2022 for Swot) and averaged over 1 second. All instrumental, geophysical and environmental corrections are included for near-real and delayed-time products.

Use: from operational oceanography and marine meteorology (real time products) to the study of ocean variability.

Description: mono altimeter satellite products available in near-real time and in delayed time. SSHA from Jason-3, Saral and Swot are divided into three families, distinguished by increasing latency and accuracy, going from the near-real time data (OGDR-SSHA) to the delayed-time data (IGDR-SSHA, GDR-SSHA).

Geographic coverage: global

Format: NetCDF. All three products have the same format.

Tools:

 

Disclaimer about SWOT Geophysical Data Record products:

February 2024:
Production and distribution of the SWOT NALT and RAD GDR products:
- Datasets are from Cycles 400 to 578 (January 15 – July 10, 2023) during the SWOT commissioning and calibration phases (1-day repeat orbit), and Cycles 1-6 (July 21 – November 23, 2023) during the science phase (21-day repeat orbit).
- Please note that some passes are not available in the later portion of cycle 578, and very early portions of Cycles 402 and 1 during orbit transitions as well as instrument turn on.

October 2023:
- Release of the reprocessed SWOT 1-day orbit IGDR nadir altimeter products for the period from March 29 to July 10, 2023.
- Please note that some gaps remain in the reprocessed IGDR time series because either the raw IGDRs were not available or the available IGDRs could not be processed with the current version of the processing software.

September 2023:
Production and release of O/I(GDR) products have resumed in nominal conditions.
- Distribution of the OGDR science data products resumes from September 7, 2023 and onwards.
- Distribution of the IGDR science data products starts from July 21, 2023 and onwards.

July 2023
- (O/I)GDR production and distribution are temporarily interrupted from July 11, 2023 for the platform transfer to the Science orbit. Users will be notified when the service will resume.
- On-ground instrumental corrections will be updated upon production restart after the orbit change (MLE3 and MLE4 retrackers).
- Improved orbit state flag will be implemented upon production restart after the orbit change.

June 2023:
The SWOT project is pleased to announce the public release of Level 2 data products from the onboard nadir altimeter (NALT) and advanced microwave radiometer (RAD).
- The datasets are from Cycle 559, pass 1 (on June 21, 2023) onward.
- They have been generated with post-launch calibrations for both the NALT and RAD.
- Data from earlier will be provided when the Geophysical Data Record (GDR) will be released by the end of 2023.

 

OGDR-SSHA

Description: The OGDR-SSHA is a near-real time operational product. The OGDR is the faster product delivered to the users. Note that this is a non-validated product that uses orbits computed by the on-board Doris Navigator (DIODE) and that it does not contain all the environmental/geophysical corrections. The file structure are not with pole to pole passes but with variable segments.

Copyright : 2008- ongoing Eumetsat - Noaa for Jason-2 data, 2013-ongoing Isro/Eumetsat for Saral/AltiKa data, 2023-ongoing Cnes and Nasa for O/I/GDR Swot

Note: the official dissemination of SARAL OGDR products is under the responsibilty of EUMETSAT and ISRO. CNES declines any responsability in case of products latency or gaps happening on the ftp server.

Satellite Distribution Frequency Data period File weight
Swot  Available via your personal space: MY AVISO+, select the product "GDR / IGDR (Geophysical Data Records)" in the page "My products"
(dedicated credentials are necessary, please fill the form on the registration form)
3-5 hours 2023/06/21 - ongoing -
Saral FTP available on MY AVISO+ (see GDR / IGDR (Geophysical Data Records)) 3-5 hours June 2013- ongoing 300 KB per file (zipped)

OGDR-SSHA Value-added

Description: The OGDR-SSHA value-added is a near-real time operational product.  The major difference between these data and the Operational Geophysical Data Record (OGDR) data produced by the project is that the orbits have been improved. You will find complete information on JPL website for Saral/AltiKa 

Copyright : 2013-ongoing JPL/Nasa for Saral/AltiKa data and 2009-ongoing JPL/Nasa for Jason-2 data.

Satellite Distribution Frequency Data period File weight
Saral see JPL site 7-9 hours June 2013- ongoing 500 KB per file (zipped)

IGDR-SSHA

Description: 

Saral: The IGDR-SSHA is a delayed time dataset produced within 1-2 days. They are produced solely by Cnes.

These data are not fully validated (elementary and automatic controls only) and are derived from Doris data with the processing of a preliminary orbit. The environmental and geophysical corrections (preliminary for some of them) are included. The file structure is pole to pole passes.

Copyright: 2008- ongoing Cnes for Jason-2 and 2013-ongoing Cnes for Saral data, 2016-ongoing for Jason-3, 2023-ongoing Cnes and Nasa for O/I/GDR Swot

Satellite Distribution Frequency Data period File weight
Swot  Available via your personal space: MY AVISO+, select the product "GDR / IGDR (Geophysical Data Records)" in the page "My products"
(dedicated credentials are necessary, please fill the form on the registration form)
1-2 days 2023/06/21 - ongoing -
Jason-3 FTP available on MY AVISO+ (see GDR / IGDR (Geophysical Data Records)) 1-2 days last month online 180 Kb
Saral 1-2 days last month online 140 Kb
Jason-2 2 days  last month online 150 Kb

See also IGDR products available on the catalogue (through menu DATA)

GDR-SSHA

Description: The GDR-SSHA is a delayed-time dataset produced within 60 days. They are produced solely by Cnes and are available to users from Aviso and Noaa. These data are fully validated and are derived from Doris, GPS and laser data Precise Orbit Determination. All the environmental and geophysical precise corrections are included. The file structure is pole to pole passes.

Copyright: 2008-ongoing Cnes, 2023-ongoing Cnes and Nasa for O/I/GDR Swot

Satellite Distribution Frequency Data period File weight
Swot Available via your personal space: MY AVISO+, select the product "GDR / IGDR (Geophysical Data Records)" in the page "My products"
(dedicated credentials are necessary, please fill the form on the registration form)
~90 days - -
Jason-3 FTP available on MY AVISO+ (see GDR / IGDR (Geophysical Data Records)) 60 days Feb. 2016 - ongoing 180 KB
Saral 35 days March 2013- on going 135 KB
Jason-1 30 days January 2002 - on going 150 KB
Jason-2 60 days  July 2008 - on going 250 KB

See also GDR products available on the catalogue (through menu DATA)