The Copernicus Sentinel-6 mission: Enhanced continuity of satellite sea level measurements from space

Given the considerable range of applications within European Union Copernicus system, sustained satellite altimetry missions are required to address operational, science and societal needs. This article describes Sentinel-6 mission that is designed provide precision sea level, surface height, significant wave inland water heights other products tailored operational services in ocean, climate, atmospheric land Services. provides enhanced continuity very stable time series mean level measurements ocean state started 1992 by TOPEX/Poseidon follow-on Jason-1, Jason-2 Jason-3 missions. The implemented through a unique international partnership with contributions from NASA, NOAA, ESA, EUMETSAT, (EU). It includes two satellites will fly sequentially (separated 5 years). first satellite, named Michael Freilich, launched Vandenburg Air Force Base, USA on 21st November 2020. payload elements explained including performance their operation. main Poseidon-4 dual frequency (C/Ku-band) nadir-pointing radar altimeter uses an innovative interleaved mode. enables data processing parallel chains synthetic aperture (SAR) Ku-band improve received echoes better along-track sampling reduced measurement noise; second Low Resolution Mode fully backward-compatible historical reference measurements, allowing complete inter-calibration between state-of-the-art record. A three-channel Advanced Microwave Radiometer for Climate (AMRC) vapour mitigate degradation measurements. preliminary in-orbit presented demonstrate be performing expectations.