The first SAR was launched into space by Europe’s Ariane-4 rocket in July 1991 as one of three main instruments on ESA’s ERS-1 spacecraft. It was followed by a second on ERS-2 in 1995.
At the time the two ERS satellites were the most sophisticated Earth observation spacecraft ever developed and launched in Europe.
ERS-1 completed its operation in 1999, overlapping with the new ERS-2, which was launched in 1995. These highly successful ESA satellites have collected a wealth of valuable data on the Earth’s land surfaces, oceans, and polar caps.
They have been called upon to monitor natural disasters like severe flooding or earthquakes in remote parts of the world.
On a global scale they have expanded our understanding of the interaction between the oceans and atmosphere, ocean currents and changes in the Arctic and Antarctic ice, giving climatologists more confidence in assessing climate trends.
The ERS satellites have also kept a close eye on agricultural areas, forests, coastlines and marine pollution.
By detecting land-use changes, such as the destruction of tropical rain forests, ERS data has helped governments around the world 'police' a broad range of local and global environmental problems.