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SWOT Level 2 Nadir Altimeter Geophysical Data Record with Waveforms Version D

Published by Jet Propulsion Laboratory;NASA/JPL/PODAAC | National Aeronautics and Space Administration | Catalog Last Checked: November 11, 2026 at 12:08 AM | Dataset Last Updated: November 05, 2026
The SWOT Level 2 Nadir Altimeter Geophysical Data Record (GDR) with Waveforms dataset produced by the Surface Water and Ocean Topography (SWOT) mission provides sea surface height, significant wave height and wind speed measurements from the Poseidon-3C nadir altimeter, a Jason-class dual frequency (Ku/C) altimeter. SWOT is a joint mission between NASA and CNES that launched on December 16, 2022. It aims to measure ocean surface topography with unprecedented resolution and accuracy, as well as map inland water bodies globally. The GDR dataset consists of discrete measurements for each half orbit along the ground track with sampling resolutions of approximately 6-km and 300-m at 1Hz and 20Hz, respectively. The data were processed using restituted auxiliary data and the Precise Orbit Ephemeris (POE). The data are available with latency of < 90 days and distributed in netCDF-4 file format. This collection is the parent collection to the following sub-collections: https://podaac.jpl.nasa.gov/dataset/SWOT_L2_NALT_GDR_SSHA_D https://podaac.jpl.nasa.gov/dataset/SWOT_L2_NALT_GDR_GDR_D https://podaac.jpl.nasa.gov/dataset/SWOT_L2_NALT_GDR_SGDR_D

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Complete Metadata
@type dcat:Dataset
accessLevel public
bureauCode 
[
  "026:00"
]
contactPoint 
{
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  "@type": "vcard:Contact",
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}
description The SWOT Level 2 Nadir Altimeter Geophysical Data Record (GDR) with Waveforms dataset produced by the Surface Water and Ocean Topography (SWOT) mission provides sea surface height, significant wave height and wind speed measurements from the Poseidon-3C nadir altimeter, a Jason-class dual frequency (Ku/C) altimeter. SWOT is a joint mission between NASA and CNES that launched on December 16, 2022. It aims to measure ocean surface topography with unprecedented resolution and accuracy, as well as map inland water bodies globally. The GDR dataset consists of discrete measurements for each half orbit along the ground track with sampling resolutions of approximately 6-km and 300-m at 1Hz and 20Hz, respectively. The data were processed using restituted auxiliary data and the Precise Orbit Ephemeris (POE). The data are available with latency of < 90 days and distributed in netCDF-4 file format. This collection is the parent collection to the following sub-collections: https://podaac.jpl.nasa.gov/dataset/SWOT_L2_NALT_GDR_SSHA_D https://podaac.jpl.nasa.gov/dataset/SWOT_L2_NALT_GDR_GDR_D https://podaac.jpl.nasa.gov/dataset/SWOT_L2_NALT_GDR_SGDR_D
distribution 
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identifier 10.5067/SWOT-NALT-GDR-D
keyword 
[
  "earth-science-ocean-waves-oceans-significant-wave-height",
  "earth-science-sea-surface-topography-oceans-sea-surface-height"
]
license https://www.usa.gov/government-works
modified 2026-11-05
programCode 
[
  "026:000"
]
publisher 
{
  "name": "Jet Propulsion Laboratory;NASA/JPL/PODAAC",
  "@type": "org:Organization"
}
spatial 
"["CARTESIAN", [{"WestBoundingCoordinate": -180.0, "NorthBoundingCoordinate": 77.6, "EastBoundingCoordinate": 180.0, "SouthBoundingCoordinate": -77.6}]]"
theme 
[
  "Earth Science"
]
title SWOT Level 2 Nadir Altimeter Geophysical Data Record with Waveforms Version D

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