Given the considerable range of applications, sustained altimetry satellite missions are required to address operational science and societal needs.

Within Copernicus, the twin-satellite polar-orbiting Sentinel-3 and the Sentinel-6 Michael Freilich reference missions will work together as a Copernicus altimetry constellation, to monitor global sea level changes and ensure a complete record of sea level for the coming decades.

In particular, Copernicus Sentinel-6 Michael Freilich mission objectives include:

1. Continuation of data for Copernicus services – Copernicus Sentinel-6 Michael Freilich satellites will be launched sequentially into the Jason satellite series orbit (±66° latitude) to overlap and continue the services initiated by TOPEX/Poseidon, and currently maintained by the Jason reference altimeter series.
2. An operational mission for Copernicus Services- Meaning that the mission will meet the needs of Copernicus and other operational services with excellent reliability and strict data delivery timeliness, including weather and ocean forecasting services.
3. Products for scientific research - This objective reflects the role of Copernicus Sentinel-6 Michael Freilich as the altimetry reference mission and is the motivation for requirements related to measurement and product quality.
4. Long-term data series from heritage reference missions - This objective leads to requirements on the content of the data products, as well as on the continuity of the space-time sampling between missions occupying the 66° reference orbit.
5. Contribution to marine meteorology - By providing Significant Wave Height and Wind Speed observations in near real-time, this objective also motivates requirements on the content of the data products, their availability and delivery timeliness.
6. Support to coastal oceanography - This objective enhances the heritage measurements by building on new techniques in radar altimetry (developed by Copernicus Sentinel-3 and ESA's CryoSat) to improve the performance of the mission in coastal areas (re-tracking and high-resolution wet tropospheric correction).
7. Secondary objectives (that do not drive the mission design), the mission will provide Radio Occultation measurements in support of numerical weather prediction forecasts. Building on the capability demonstrated by Copernicus Sentinel-3, the mission will also provide measurements to determine the height of inland waters in support of Copernicus water management applications.