The NOAA Laboratory for Satellite Altimetry's (LSA) sea surface height team produces 0.25-degree longitude/latitude Level-3 sea level anomaly (SLA) daily datasets by applying optimal interpolation to along-track satellite observations over the global ocean from a constellation of radar altimeter missions. Theses grids are produced with near-real time (3-5 hour latency) data.

The altimetry data are from RADS (, the Radar Altimetry Database System, first developed at Delft University of Technology, now also at the NOAA and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT). The RADS data for each mission is updated with state of the art corrections for tides, atmospheric path delay, etc. Because they are all computed consistently between the various missions, this avoids the possibility of introducing biases and drifts because of the different implementation of the various corrections by different agencies. The goals of RADS are to provide a homogenous dataset of sea level anomalies, wave heights, and wind speeds, along with database selection and analysis tools.


Key Description
Platform/Sensor Jason-2; Jason-3; Sentinel-3A; CryoSat-2; SARAL
Measurement/Products Earth Science >Oceans > Surface Sea Surface Height
DOI n/a
Short Name RADS-NRT-SLA-Daily-L3
Sample Filename 1-day:
Dataset Type n/a
Processing Level L3
Spatial Coverage Global
Temporal Coverage 1 January 2017 - current
Resolution 0.25x0.25 longitude/latitude degree
Projection n/a
Latency 12 hours
Swath Width n/a
Sample Frequency n/a
Temporal Repeat Jason-2/Jason-3: 9.9156 days;
Sentinel-3A: 27 days;
CryoSat-2: 369 days;
SARAL: ~35 days
Orbital Period Jason-2/Jason-3: 112.4 minutes;
Sentinel-3A: 101 minutes;
CryoSat-2: 100 minutes;
SARAL: 100.6 minutes
Orbit n/a
Data Provider Creator: Eric Leuliette, NOAA/NESDIS/STAR/SOCD/LSA
Keywords Jason-2; Jason-3; Sentinel-3A; CryoSat-2; SARAL; sea surface height; sea level anomalies
Formats n/a

Data Access

Data are available through the following servers:
Service Resource Locator

[Please acknowledge "NOAA CoastWatch/OceanWatch" when you use data from our site and cite the particular dataset DOI as appropriate.]


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