Meteosat: 30 years of meteorological data and images from geostationary orbit

When the Delta rocket carrying the first Meteosat lifted off from Cape Canaveral in November 1977, Europe gained the ability to gather weather data over its own territory with its own satellite. Meteosat began as a research programme for a single satellite by the European Space Research Organisation, a predecessor of the European Space Agency (ESA). Once the satellite was in orbit, the immense value of the images and data it provided led to the move from a research to an operational mission requiring a dedicated organisation to conduct it. In anticipation of the founding of EUMETSAT, ESA launched the Meteosat Operational Programme (MOP) in March 1983. This covered the construction and launch of three more Meteosat satellites and all operational activities until November 1995. EUMETSAT ultimately became reality in June 1986, with the operational provision of Meteosat images and data as its initial raison d’etre.

Meteosat operated by EUMETSAT

As from 1987, EUMETSAT took full financial and programmatic control over MOP, although ESA continued to manage the programme on behalf of EUMETSAT, developing the space segment and procuring the satellites. Meteosat-4, EUMETSAT’s first operational satellite, was launched in March 1989, followed over the next four and a half years by Meteosat-5 and Meteosat-6.

Between 2001 and 2007 Meteosat-6 provided EUMETSAT’s new rapid-scanning service, supplying frequent data of a smaller area to monitor the development of convective storms. Meanwhile, in May 1991, the Meteosat Transition Programme (MTP) was initiated, with funding covering the construction, launch and operation of Meteosat-7. Launched in September 1997, Meteosat-7 was the last of the first generation of Meteosat satellites.

Generation change

The first generation of seven Meteosat satellites brought major improvements to weather forecasting. But technological advances and increasingly sophisticated weather forecasting requirements created demand for more frequent, more accurate and higher resolution space observation.

To meet this demand, EUMETSAT launched the Meteosat Second Generation (MSG) programme, in coordination with ESA, which developed the first satellite and procured all four with EUMETSAT funding. On 28 August 2002, EUMETSAT launched the first MSG satellite, renamed Meteosat-8 when it began routine operations to clearly maintain the link to earlier European weather satellites. It is the first of four MSG satellites, which are gradually replacing the original Meteosat series. It was followed on 21 December 2005 by the second MSG satellite, Meteosat-9, which currently provides the operational service over Europe with Meteosat-8 as backup. Meteosat-8 is preparing to take up rapid scanning as from spring 2008.

Together, the two satellites provide the operational service for Europe of a quality never before experienced from geosynchronous orbit. At the same time, work continues on MSG-3 and MSG-4, which are scheduled for launch in January 2011 and January 2013, respectively. The first generation, however, is still going strong; Meteosat-5 was only de-orbited very recently - in April 2007 - after more than 15 years of operational service. The remaining Meteosats of the first generation - Meteosat-6 and Meteosat-7 - are in orbit over the Indian Ocean as part of the World Meteorological Organization’s Global Observing System. To enable Europe to meet its obligations to the Global Observing System, EUMETSAT and ESA are currently preparing for Meteosat Third Generation (MTG).

Increasing capabilities

The capabilities of Meteosat are increasing with each generation to meet growing user requirements. The 800-kilogram MOP/MTP has one mission with its three-channel Meteosat Visible and Infrared Imager (MVIRI) and a repeat cycle of 30 minutes, while the two-ton MSG conducts observation missions with its 12-channel Spinning Enhanced Visible and Infrared Imager (SEVERI) with repeat cycles of 15 minutes in nominal mode and five minutes in rapid-scanning mode at extraordinarily high resolution (one kilometre for the High Resolution Channel from geostationary orbit). It also has the Geostationary Earth Radiation Budget (GERB) instrument for a dedicated climatology mission.

Unlike the two previous generations of Meteosat spinning satellites, the three-ton MTG will be three-axis stabilised and each satellite will have different payloads for four different observation missions. The first MTG satellite will carry a 16-channel combined imager capable of providing both full disk high spectral resolution imagery and fast imagery and, if approved, a lightening imager. The second MTG will have an infra-red sounder, and a possible chemistry mission using an Ultra Violet Sounder is also being coordinated with the European Space Agency for implementation via the Sentinel 4 satellite operating under the Global Monitoring for Environment and Security programme.

EUMETSAT ground system

Satellites are just one element of Meteosat; an extended ground system is required to control them and handle the data they collect. Data and images gathered by operational satellites are received by primary and backup ground stations, relayed for processing to EUMETSAT’s MSG Mission Control Centre in Darmstadt, Germany, from where the satellites are also controlled. The data are processed at EUMETSAT’s Meteorological Products Extraction Facility into more manageable digital products and tools which are made available to the National Weather Services of EUMETSAT Member and Cooperating States and a growing network of other users all over the world. The high-quality processed data and services are delivered at a low cost by EUMETCast, EUMETSAT’s broadcast system for environmental data, to these users in near real time via digital video broadcast.

The MSG ground segment includes a Europe-wide network of Satellite Application Facilities (SAFs) located at the National Meteorological Services of EUMETSAT member states. Each MSG-related SAF specialises in a specific area: Nowcasting and Very Short Range Forecasting, Ocean and Sea Ice, Ozone Monitoring and Atmospheric Chemisty, Climate Monitoring, Numerical Weather Prediction, Global Navigation Satellite System Receiver for Atmospheric Sounding Meterology (GRAS), Land Surface Analysis, and Support for Operational Hydrology and Water Management.