Because both ERS-1 and ERS-2 significantly exceeded their original design lifetime of three years, it was possible to build an extended, continuous and homogeneous time series of oceanographic measurements, which were not previously possible.
In particular, accurate measurements of sea surface height variation by the radar altimeter instrument provided a unique capability to monitor variations in currents at the regional level while the Along Track Scanning Radiometer (AATSR) series of instruments have delivered a highly accurate time series of sea surface temperature variations over a 16-year period.
In addition, satellite data from the radar altimeters onboard ESAs ERS-1, ERS-2 and Envisat and NASA/CNES Topex-Poseidon detected a trend in sea level rise between 2.64 and 3.29 mm/year over the last 15 years.
In 2002, the newly launched Envisat acquired images of the Prestige oil spill in Spain with its Advanced Synthetic Aperture Radar (ASAR) instrument. Since this time, ESA has been working within the Global Monitoring for Environment and Security (GMES) Services Element to demonstrate and qualify the capacity for pan-European oil spill surveillance. Last year, an operational satellite-based oil slick detection service based on SAR data from Envisat and the Canadian Radarsat satellite was set up for all European waters under the European Maritime Safety Agency (EMSA). The service, named CleanSeaNet, is the first operational pan-European satellite based surveillance service for European waters.
Under this service, a notification of a pollution event can be provided within 20 to 30 minutes of the satellite overpass. By integrating the SAR oil slick information with vessel information, it becomes possible to identify potentially responsible vessels.
"This is a first, and significant, step in the process whereby EMSA assists Member States and th
|Contact: Mariangela D'Acunto|
European Space Agency