Europe’s Sentinel-3 global ocean-monitoring constellation in orbit

Sentinel-3A measures height of Antarctic ice sheet ESA
Sentinel-3A measures height of Antarctic ice sheet ESA

Copernicus Sentinel-3B of the European Space Agency (ESA) has returned its first images. Sentinel-3A, launched in February 2016, and Sentinel-3B carry the same set of instruments – Ocean and Land Colour Instrument (OLCI), Sea and Land Surface Temperature Radiometer (SLSTR), and Synthetic Aperture Radar Altimeter (SRAL) – to measure Earth’s oceans, land, ice and atmosphere with a revisit time of a day or two and a resolution ranging from 300 meters to a kilometer depending on the instrument. Over oceans, these satellites measure the temperature, colour and height of the sea surface as well as the thickness of sea ice.  They will be used to monitor the onset and evolution of future El Niño events, monitor surface wind speed and changes in surface ocean waters, sea-state, sea-ice thickness, and for estimating the heat content of the upper ocean.