Along-track Sea Level Anomalies Level-2+ (L2P)

Sentinel-3 A/B Altimetry L2P products will be discontinued as of January 1, 2025.
Users are encouraged to use EUMETSAT Level 2 (L2) products or CMEMS Level 3 (L3) products instead.

Types of dataset: Monomission altimeter product, available for several missions. 

Digital Object Identifiers (DOIs): 

• L2P NTC 1Hz: 10.24400/527896/A01-2025.004 - more metadata

Contents: along-track corrected sea level anomalies with corrections wrt reference ellipsoid. Datasets of 1Hz spatial resolution for all missions + datasets of 20Hz spatial resolution for Copernicus Sentinel-3A&B, Sentinel-6MF, Jason-3 in Short Time Critical (STC) and Near-Real-Time (NRT)

Use: stationary or long-term geophysical and ocean phenomenon studies.

Description: Mono altimeter satellite product, with corrections and geophysical parameters. Note that monomission products by definition are not intercalibrated at crossover points. Thus Jason-1 and Envisat data for example may not be homogeneous at a given point, since their orbits are different. Note also that these products are not corrected from Large Wavelength Error (LWE), unlike multimission Ssalto/Duacs products. Check monomossion processing last updates. 

Geographic coverage: Global, the maximum coverage in latitude depends on the mission.

Format: NetCDF-CF

Tools and reference:

• User handbook:
  • Copernicus Sentinel-3 & Sentinel-6 Along-track Sea Level Anomalies Level-2+ (L2P) Product Handbook (1Hz and 20Hz datasets)
  • Along-track Sea Level Anomalies Level-2+ (L2P) Product Handbook (all missions except Sentinel-3&6) (1 Hz datasets)
  • Along-track Sea Level Anomalies Level-2+ (L2P) high frequency Product Handbook (all missions except Sentinel-3&6) (20 Hz datasets)
  • The list of 2024 standards is given in the file standards_2024.png
• C. Kocha et al. 2023:  30 years of sea level anomaly reprocessed to improve climate and mesoscale satellite data record. DOI 10.24400/527896/a03-2023.3804 , OSTST 2023 meeting.,
• Kocha et al. 2023: Latest update of sea level rise: 30 years of multi-mission datasets EUMETSAT 2023 conference.,
• Lievin et al. 2023. Assessment of reprocessed L2P sea level anomaly products with DT2024 standards (focus on Sentinel-3). S3VT 2023 meeting.
• Quality reports: Daily Sentinel-3 L2P product quality monitoring reports, available for Near-Real-Time (NRT) and Short Time Critical (STC) products on the authenticated FTP and for Non-Time-Critical (NTC) products on the authenticated FTP.

The use of Copernicus Sentinel-3 and Sentinel-6 Michael Freilich products is described in the license agreement (section 13. Licence specific to Sentinel-3 L2P products).

Citations:

• for Copernicus Sentinel-3 & Sentinel-6 Michael Freilich missions, please refer to the license agreement to mention credits explicitly in function of your use (section 13. Licence specific to Sentinel-3 L2P products).
• for the other missions, please cite: "The altimeter products were produced and distributed by Aviso+ (https://www.aviso.altimetry.fr/), as part of the Ssalto ground processing segment"

Copyright :

• for Copernicus Sentinel-3 & Sentinel-6 Michael Freilich missions: 2016-ongoing CNES/CLS consortium under an EUMETSAT Contract, funded by the European Union. Further information in the license agreement
• for the other missions : 1992- ongoing Cnes-CLS

to get access Aviso products and select the products "Sea Level Anomalies Along-track Level-2+ (L2P) Sentinel-3&6" and/or "Sea Level Anomalies Along-track Level-2+ (L2P) for other missions"

Near-Real-Time (NRT) L2P SLA

Satellite	Distribution media	Quality reports	Delivery delay	Data period	Data used	File weight
Sentinel-3A 1Hz	Please refer to   MY AVISO+	Please refer to MY AVISO+	4 hours	2 months	one pass per file	<100 Ko per file (zipped)
Sentinel-3A 20Hz			twice a day	2 months		<3.5 Mo per file
Sentinel-3B 1Hz			4 hours	2 months		<100 Ko per file (zipped)
Sentinel-3B 20Hz			twice a day	2 months		<3.5 Mo per file
Jason-3 20Hz			twice a day	2 months		4 Mo per file
Sentinel-6A MF 1Hz HR			4 hours	2 months		<130 Ko per file (zipped)
Sentinel-6A MF 20Hz HR			twice a day	2 months		<3.5 Mo per file

Short Time Critical (STC) L2P SLA

Satellite	Distribution media	Quality reports	Delivery delay	Data period	Data used	File weight
Sentinel-3A 1Hz	Please refer to MY AVISO+	Please refer to MY AVISO+	56 hours	2 months	one pass per file	<100 Ko per file (zipped)
Sentinel-3A 20Hz			twice a day	2 months		<3.5 Mo per file
Sentinel-3B 1Hz			56 hours	2 months		<100 Ko per file (zipped)
Sentinel-3B 20Hz			twice a day	2 months		<3.5 Mo per file
Jason-3 20 Hz			every day	2 months		4 Mo per file
Sentinel-6A MF 1Hz HR			44 hours	2 months		<130 Ko per file (zipped)
Sentinel-6A MF 20Hz HR			twice a day	2 months		<3.5 Mo per file

Non Time Critical (NTC) L2P SLA

Satellite	Distribution media	Quality reports	Delivery delay	Data period	Data used	File weight
Sentinel-3A 1Hz	Please refer to  MY AVISO+	Please refer to  MY AVISO+	1.5 month	jun 2016 - ongoing	one pass per file	<100 Ko per file (zipped)
Sentinel-3B 1Hz			1.5 month	nov 2018 - ongoing
Sentinel-6A 1Hz HR			1.5 month	sept 2021 - ongoing
Sentinel-6A 1Hz LR			1.5 month	sept 2021 - ongoing
Jason-3 1Hz		-	3 months	feb 2016 - ongoing
HY-2B 1Hz		-	3 months	dec 2019 - aug 2023
Jason-2 1Hz		-	-	jul 2008 - sep 2017
Jason-1 1Hz		-	-	jan 2002 - jun 2013
Saral 1Hz		-	3 months	mar 2013 - ongoing
Cryosat-2 1Hz		-	3 months	jan 2011 - ongoing
HY-2A 1Hz		-	-	apr 2014 - jun 2020
Envisat 1Hz		-	-	may 2002 - apr 2012
ERS-1 1Hz		-	-	oct 1992 - jun 1996
ERS-2 1Hz		-	-	may 1995 - sep2003
T/P 1Hz		-	-	sep 1992 - sep 2005
GFO 1Hz		-	-	jan 2000 - sep 2008