The Meteorological Operational satellite programme (MetOp) is a new European undertaking providing weather data services that will be used to monitor climate and improve weather forecasts. The MetOp programmes series of three satellites  has been jointly established by ESA and the European Organisation for the  Exploitation of Meteorological Satellites (EUMETSAT), forming the space segment of EUMETSAT's Polar System (EPS).
 
The  programme also represents the European contribution to a new cooperative venture  with the United States National Oceanic and Atmospheric Administration (NOAA),  which for the last 40 years has been delivering meteorological data from polar  orbit, free of charge, to users worldwide.

Launching in July 2006, MetOp-A, the first satellite in the series, will replace one of two satellite services currently operated by NOAA and will be Europes first polar-orbiting satellite dedicated to operational meteorology. Once MetOp-A launches, responsibilities for such meteorological satellite  services will be shared between the U.S. and Europe.

MetOp-A has been designed to work in conjunction with the NOAA satellite system whereby the two satellites fly in complementary orbits. MetOp-As polar  orbit is Sun synchronous, so that the satellite track along the Earth is always  at the same local time, in this case in the mid-morning. NOAA will continue to  operate its mid-afternoon orbit satellite service as part of the Polar Orbit  Enviromental Satellites (POES) system.

Polar orbiting satellites orbit at a lower altitude  typically 800 km compared with 36 000 km for a geostationary  satellite and can observe the Earth in closer detail. This global observing system will be able to provide invaluable meteorological data from polar orbit to users within 2 hours and 15 minutes of the measurements being taken, with regional users being able to receive data in real time. With an array of sophisticated instrumentation, MetOp-A promises to provide  data of unprecedented accuracy and resolution on a host of different variables such as temperature and humidity, ocean surface wind speed and direction and concentrations of ozone and other trace gases – thus marking a major advance in global weather forecasting and climate monitoring capabilities. In addition, this new weather satellite provides imagery of land and ocean surfaces as well as search and rescue equipment to aid ships and aircraft in  distress. A data relay system is also on-board, linking up to buoys and other  data collection devices. Of the instruments on board, five are new-generation European instruments, whilst the others have a well-proven heritage and have been provided by NOAA and  the French Space Agency (CNES). The three MetOp satellites will be launched, nominally each 5 years, to  ensure the delivery of continuous, high-quality global meteorological data until  at least 2020.