Full Name Poseidon-4 SAR Radar Altimeter Status Operational
Instrument Agencies CNES, ESA Maturity
Instrument Type Radar altimeters Geometry Nadir-viewing
Instrument Technology Radar altimeter Sampling Sounding
Data Access Open Access Data Format NetCDF-4
Measurements and Applications Nadir viewing sounding radar for provision of real-time high-precision sea surface topography, ocean circulation and wave height data.
Resolution Summary
Swath Summary On baseline TOPEX/POSEIDON orbit (10 day cycle): 300 km between tracks at equator.
Accuracy Summary Sea level: 3.2 cm, Significant wave height: 0.15 m, Horizontal sea surface wind speed: 1.5 m/s
Waveband Summary Microwave: Ku-band (13.575 GHz), C-band (5.3 GHz)
Ku-Band (12.5 to 18 GHz)
C-Band (8 - 4 GHz)
Instrument Measurements
Measurements Overview
Gravity, Magnetic and Geodynamic measurementsGeoid
Landscape topographyLand surface topography
Ocean surface windsWind speed over sea surface (horizontal)
Ocean topography/currentsSea level
Ocean wave height and spectrumSignificant wave height
Thematic Links Global Climate Observing System Essential Climate Variables (GCOS ECVs)
ECVDescriptionProduct(s)ECV Inventory 3.0 Record(s)
Sea Level click here click here search ECV Inventory records
Sea State click here click here search ECV Inventory records
Instrument Missions
Sentinel-6 A Michael Freilich - Sentinel-6 Michael Freilich (2020 - 2026)
Sentinel-6 B - Sentinel-6 B (2025 - 2031)