Copernicus Sentinel-6B enters operational service, extending the sea-level record

EUMETSAT, operating on behalf of the European Commission, declared the Copernicus Sentinel-6B altimetry satellite operational on 30 October 2026. The mission carries the global sea-level record, begun in 1992 with TOPEX/Poseidon and the Jason series, into the 2030s. Data reach users within about three hours and are freely available worldwide.

Sentinel-6B has flown alongside its twin, Sentinel-6 Michael Freilich (launched November 2020), since December 2025, 30 seconds apart at 1,336 km, to allow calibration. Within months it should be formally adopted as the international reference, after which the older satellite will shift to a new orbit to widen ocean coverage.

The data feed weather and ocean forecasts, seasonal predictions such as El Niño, and Copernicus climate services. A radio occultation instrument adds temperature and water vapour profiles, and a high-resolution mode covers coastlines and inland waters. Sea level has risen more than 11.5 cm since December 1992.

Why it matters: Continuity of a calibrated altimetry record underpins sea-level monitoring, coastal planning and ocean forecasting. The high-resolution coastal and inland-water mode and free data access are useful for coastal and water-resource work, including in Africa.