The Advanced Microwave Radiometer for Climate monitoring (AMR-C) integrated on the Copernicus Sentinel-6A satellite at Airbus in Germany. As part of the international cooperation for this mission, the radiometer has been supplied by NASA JPL. The satellite’s main instrument is a radar altimeter to measure sea-surface height. The radiometer accounts for the amount of water vapour in atmosphere, which affects the speed of the altimeter’s radar pulses. Copernicus Sentinel-6 will be a two-satellite constellation to monitor global sea level to understand long-term climate variations. Importantly, the mission will continue the measurements that have been supplied by the Topex-Poseidon and Jason missions since the 1990s.