ERS was the first ESA programme in Earth observation with the overall objectives to provide environmental monitoring in particular in the microwave spectrum.

This involved the regular monitoring of land-surface and ocean-surface processes for change detection, polar ice, land ecology, geology, forestry, wave phenomena, bathymetry (water depth), atmospheric physics, geoid mapping, meteorology and more.

Scientific research included PIPOR (Program for International Polar Ocean Research); PISP (Polar Ice Sheet Proposal). Demonstration of concept and technology for space and ground segments (performance and operational capability).