ESA's Sentinel-3: An Operational Oceanography Mission for GMES
Mark R. Drinkwater(1) , Helge Rebhan(1) , Miguel Aguirre(1) , and Yvan Baillon(2)
European Space Agency,
2201AZ Noordwijk ZH,
(2) Alcatel Alenia Space, 100 Boulevard du Midi, BP 99., 6156 Cannes, France
The European Space Agency (ESA) recently initiated an industrial definition phase study activity for a satellite mission that shall provide operational continuity to specific ocean surface observations in the post Envisat era (2010 onwards). This mission, known as GMES Sentinel-3 forms part of the Earthwatch line of missions within ESA's Living Planet Programme, and addresses the sustained observational requirements of the ESA/EU Global Monitoring for Environment and Security (GMES) programme.
GMES Sentinel-3, is one of the first EarthWatch mission concepts to be thoroughly studied to address global operational oceanography monitoring issues requiring long-term, systematic, and robust data collection and processing. The required measurements to be supported by this operational satellite mission are sea-surface topography (SSH), sea-surface temperature (SST), and ocean colour (OC) characteristics. Some of these data streams form the kernel of products used in the latest generation of ocean forecasting models being developed under the data assimilation schemes of the FP6 MERSEA large-integrated projects, as well as operational Numerical Weather Prediction models. Other examples that will directly use Sentinel-3 data are the ESA MEDSPIRATION study and the GODAE GHRSST Project who are developing near real time merged SST products, as well as projects such as HABILE which is using operational ocean colour data in the study of harmful algal bloom impact on the Marine ecosystem. Sentinel-3 required ocean variables form the basis for a large number of existing product services in ESA’s GMES Service Element as well as the EC’s Marine and Coastal Service.
Initial design studies have investigated a variety of competing altimeter technological solutions, along with visible and infrared spectrometer sensor packages (with AATSR-quality SST; and MERIS quality ocean colour and vegetation products) that allow global acquisition of radiometrically accurate 250m data over a broad swath. Advances in wide-swath spectrometry may also allow the development of smaller instrument packages for use on operational satellites, and provide the basis for monitoring of primary productivity, harmful algal blooms, climate quality SST data, and routine monitoring of biogeophysical processes that determine the unknown ocean contribution to the global CO2 budget.
The status of the Sentinel-3 definition study will be reported primarily in the context of its altimetry.