Meteosat Second Generation: faster sequences and more channels

Meteosat Second Generation, or MSG, began with a launch in 2002. Four spacecraft launched between 2002 and 2015, carrying forward the geostationary weather service with improved instruments. Their operational Meteosat numbers differ from their development labels: the first MSG spacecraft became Meteosat-8. A generation names a coordinated development and service program, not one vehicle’s entire lifetime.

ESA and EUMETSAT cooperated on the system, with development and operational responsibilities supporting each other. The control-room photograph belongs to this ground infrastructure during the Meteosat 9 era. Consoles, communications and trained teams connect spacecraft observations to usable products. A functioning instrument in orbit would have limited value without reliable reception, processing and distribution.

The Spinning Enhanced Visible and Infrared Imager, SEVIRI, observes twelve spectral channels. They provide complementary information about clouds, surfaces and atmospheric conditions. The separate Geostationary Earth Radiation Budget instrument, GERB, measures broadband reflected and emitted energy. More channels and a wider spectral band are different instrument choices, serving different measurement questions.

MSG’s service design includes full-disc imagery at fifteen-minute intervals and faster regional scanning at five-minute intervals over Europe. A rapid regional scan does not give the same rapid coverage to the whole visible disc. The time interval matters when a storm changes quickly; the wavelength channels matter when deciding what physical information each image contains.

Imagine a fictional forecaster following a growing cloud system. Use consistent channels and timestamps to assess its development, then bring in radar, surface observations and model information. An image can show cloud structure while leaving uncertainty about precipitation reaching the ground. A cloud-top temperature and a rain-gauge total describe different parts of the weather system.

The ground segment — open definition also maintains calibration and archives so observations can be reused. When comparing first- and second-generation records, account for changed spectral channels, resolution and scanning patterns. A sharper picture is useful, but scientific continuity depends on understanding what changed in the measurement. The program’s improvement is therefore both an observing advance and an ongoing responsibility to document its data.