Sentinel-3 For Science Use: Optical Mission
Donlon, Craig1; Regner, Peter2; Goryl, Philippe2; Benveniste, Jerome2; Nieke, Jens1; Frerick, Johannes1

Global Monitoring for Environment and Security (GMES) is a joint initiative of the European Commission (EC) and European Space Agency (ESA), which aims at achieving an autonomous and operational Earth observation capacity. GMES marks the transition from R&D oriented efforts in earth observation towards operational servicesThe overall service duration is planned to be 20 years with several satellites. Currently, the launch of the first Sentienl-3 satellite is planned in 2014 and the second unit ~18 months later.
Sentinel-3 is an operational mission in high-inclination, low earth orbit for the provision of observational data to marine and land monitoring services. These services include the generation of land and ocean colour products, sea and land surface temperature products, and the generation of vegetation products. Full performance will be achieved with a constellation of two identical satellites, separated by 180 degrees in the same orbital plane. This configuration is driven by (i) trade-off between ocean and land coverage requirements and (ii) operational constraints.
The operational character of the mission implies a high level of availability of the data products and fast delivery time, which have been important design drivers for the mission. The Sentinel-3 spacecraft accommodates two large optical instruments - the Ocean and Land Colour Instrument (OLCI) with 21 spectral channels from 0.4 to 1.0fYm, and the Sea and Land Surface Temperature Radiometer instrument (SLSTR) with 9 spectral channels from 0.5fYm to 13fYm in nadir and oblique view directions. A topography payload consisting of a SAR Radar Altimeter (SRAL), a Microwave Radiometer (MWR) plus a suite of instruments for precise orbit determination (POD) complements the Optical payload. These instruments will ensure the continuation of important data streams established with ESA's ERS and ENVISAT satellites.
GMES Sentinel-3 is a series of operational satellites that will guarantee access to an uninterrupted flow of robust global data products. Together with the other Sentinels, this mission will fulfill the monitoring needs of the GMES marine and land services and climate research communities. The improved design of the topography and the optical payload and the corresponding data products will allow a data continuity the next decade.
This presentation will review the scientific potential of the Sentinel-3 Optical payload for the ocean, land and cryosphere domains.