The missions of Group#5 perform global measurements of gases and aerosols in the troposphere and in the stratosphere from low Earth orbits. They may embark various types of instruments, such as high-spectral resolution Imaging Spectrometers, operating with various viewing geometries (e.g. nadir, limb, and sun/moon occultations).
Depending on the sensor characteristics, these missions typically serve a huge number of near real time atmospheric applications, including:
On-board Envisat, the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS), the GOMOS and the SCIAMACHY instruments are supporting atmospheric chemistry related applications. Sentinel-5 satellites, under study for GMES, should tackle atmospheric the GMES atmospheric needs.