Mobile version


29.02.2024 14:49 Age: 142 days

SWOT: Public release of the L2 NADIR GDR (NALT) and AMR products

Category: News of the Swot mission

The Surface Water and Ocean Topography (SWOT) project is pleased to announce the public release of the Level 2 Geophysical Data Record (GDR) products from the onboard nadir altimeter (NALT) and advanced microwave radiometer (AMR).

SWOT is a joint mission between NASA and CNES and was launched on December 16, 2022. The onboard NALT is a Jason-class dual frequency (Ku/C) altimeter. The onboard AMR is also a Jason-class radiometer but with two active strings that facilitate measurements on the left and right sides of the satellite nadir point.

The datasets included in this public release 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). 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.

The NALT and AMR GDR products in this release are accessible at both NASA’s PO.DAAC and CNES AVISO distribution centers. Information on accessing these data is provided below, and further information can be found in the release note.

The SWOT Nadir Altimeter and Radiometer (O/I)-GDR products can be accessed on the AVISO+ web portal and through a new platform of the AVISO+ CNES Data Center's long-term archive catalog, accessible directly using AVISO+ credentials. Further information on SWOT data access can be found via the dedicated webpage on AVISO+:


Rss feedsContactPartnersFAQLexiconLegal noticePersonal Data Protection PolicyMobile
You must enable cookies in your browser preferences to save the modifications
You are using an older version of Internet Explorer, please update to take full advantage of Aviso+ features

Customize the home page

View all widgets
Reduce display
Public profile
User profile

Select/Deselect widgets

Discover AVISO+

Customizable home, reading tools, products search guide, etc.. Discover step by step the features of the new site AVISO+.

Customizable homepage

This home page is composed of blocks called "widgets".

Rearrange the blocks with a "Click & Drop".

Hide a widget with the cross at the top right. Reset or add a widget with the "wrench" icon. The "User" and "Public" profiles offer a predefined organization.

All the modifications are automatically saved as cookies on your machine so as to enable you to have your own specific AVISO+.

Reading tools

Ease your reading by choosing the page background colour (black/white) and/or by modifying the font size.

Browsing menu and breadcrum trail

To ease your browsing through AVISO+, you can use at any time the main banner items with the interactive submenus or use the browsing menu on the left side of the screen (it is open by default). For more readiness of the page contents, you can fold and unfold the browsing menu by clicking on the tab. At any time you can know where you are thanks to the browsing menu or the breadcrum at the top of the page.

Products search guide

The first submenu of the "Data" banner item leads you to a new search form enabling you to find quickier the product that suits your needs. The list of results is updated according to your selection criteria.

AVISO+ Multimedia

The first submenu of the "Multimedia" banner item leads you to AVISO+ collections of images and videos linked to altimetry and its applications. Have a nice visit!