The pair of Sentinel-2 satellites will routinely deliver high-resolution optical images globally, providing enhanced continuity of SPOT- and Landsat-type data.
Sentinel-2 will carry an optical payload with visible, near infrared and shortwave infrared sensors comprising 13 spectral bands: 4 bands at 10 m, 6 bands at 20 m and 3 bands at 60 m spatial resolution (the latter is dedicated to atmospheric corrections and cloud screening), with a swath width of 290 km.
The 13 spectral bands guarantee consistent time series, showing variability in land surface conditions and minimising any artefacts introduced by atmospheric variability.
The mission orbits at a mean altitude of approximately 800 km and, with the pair of satellites in operation, has a revisit time of five days at the equator (under cloud-free conditions) and 2–3 days at mid-latitudes. The first satellite is planned to launch in 2014.
The increased swath width along with the short revisit time allows rapid changes to be monitored, such as vegetation during the growing season.
Data from Sentinel-2 will benefit services associated with, for example, land management by European and national institutes, the agricultural industry and forestry, as well as disaster control and humanitarian relief operations.
Imagery for the generation of high-level operational products, such as land-cover maps, land-change detection maps and geophysical variables that use, for example, leaf area index, leaf chlorophyll content and leaf water content will be provided. Images of floods, volcanic eruptions and landslides will also be acquired by Sentinel-2.
In essence, Sentinel-2 combines a large swath, frequent revisit, and systematic acquisition of all land surfaces at high-spatial resolution and with a large number of spectral bands, all of which makes a unique mission to serve GMES.