Sentinel-3 is primarily an ocean mission, however, the mission will also be able to provide atmospheric and land applications. The mission will provide data continuity for the ERS, Envisat and SPOT satellites.
Sentinel-3 will make use of multiple sensing instruments to accomplish its objectives; SLSTR (Sea and Land Surface Temperature Radiometer), OLCI (Ocean and Land Colour Instrument), SRAL (SAR Altimeter), DORIS, and MWR (Microwave Radiometer).