The prime objective of the EUMETSAT Polar System (EPS) Metop mission series is to provide continuous, long-term datasets, in support of operational meteorological and environmental forecasting and global climate monitoring.
The EPS programme consists of a series of three polar orbiting Metop satellites, to be flown successively for more than 14 years, from 2006, together with the relevant ground facilities.
Metop-A was launched on 19 October 2006 and Metop-B was launched on 17 September 2012.
Metop carries a set of 'heritage' instruments provided by the United States and a new generation of European instruments that offer improved remote sensing capabilities to both meteorologists and climatologists. The new instruments will augment the accuracy of temperature humidity measurements, readings of wind speed and direction, and atmospheric ozone profiles.
NWP is the basis of all modern global and regional weather forecasting. The data generated by the instruments carried by Metop can be assimilated directly into NWP models to compute forecasts ranging from a few hours up to 10 days ahead. Measurements from infrared and microwave radiometers and sounders on board Metop provide NWP models with crucial information on the global atmospheric temperature and humidity structure, with a high vertical and horizontal resolution.
EPS also ensures continuity in the long-term monitoring of factors known to play an important role in climate change, for example changing patterns in the distribution of global cloud, snow and ice cover, and ocean surface temperatures and winds. In particular, the Infrared Atmospheric Sounding Interferometer (IASI) instrument has the ability to detect and accurately measure the levels and circulation patterns of gases that are known to influence the climate, such as carbon dioxide. This heralds a breakthrough in the global monitoring of the climate. The data collected by IASI feeds into the models, for the first time showing the variable global distribution of carbon dioxide as a function of seasons and circulation anomalies such as the Southern Oscillation (also known as El Niño) and the North Atlantic Oscillation (NAO).
EPS Programme Background
EPS is the European contribution to a joint European-US satellite system, called the Initial Joint Polar-Orbiting Operational Satellite System (IJPS). This is an agreement between EUMETSAT and the National Oceanic and Atmospheric Administration (NOAA). The terms of this partnership were first cemented through an agreement concluded in 1998. To develop EPS there are also cooperative agreements with the European Space Agency (ESA) and Centre National d'Etudes Spatiales (CNES).
The Initial Joint Polar-orbiting System comprises a Metop satellite from Europe and a NOAA satellite from USA. The satellites fly in complementary orbits designed to ensure global data coverage at intervals of no more than six hours.
EUMETSAT is responsible for coordinating all elements of the development, launch and operation of EPS satellites. This includes developing and procuring the ground segment; procuring the launcher and launch site, and operating the systems. Under the IJPS and Joint Transition Activities (JTA) agreement, EUMETSAT and NOAA have agreed to provide instruments for each other's satellites; exchange all data in real time, and assist each other with backup services. Other partners are the European Space Agency (ESA) and the Centre National d'Etudes Spatiales (CNES) of France.
The IJPS is a cooperative effort between EUMETSAT and the National Oceanic and Atmospheric Administration (NOAA). It is comprised of two polar-orbiting satellite systems and their respective ground segments. The IJPS programme contributes to and supports the World Meteorological Organization (WMO) Global Observing System, the Global Climate Observing System, the United Nations Environmental Programme (UNEP), the Intergovernmental Oceanographic Commission (IOC), and other related programmes.
Each satellite has a nominal lifetime in orbit of five years, with a six month overlap between the consecutive satellites (i.e. between Metop-A and Metop-B, and between Metop-B and Metop-C), providing more than 14 years of service. The European and American satellites carry a set of identical sensors: AVHRR/3 and the ATOVS suite consisting of AMSU-A, HIRS/4 and MHS. NOAA provides most of the joint instruments on board the satellites and EUMETSAT has developed and provides NOAA with the Microwave Humidity Sounder (MHS). In addition, the Metop satellites carry a set of European sensors, IASI, ASCAT, GOME-2 and GRAS, aimed at improving atmospheric soundings, as well as measuring atmospheric ozone and near-surface wind vectors over the ocean.
Metop flies in a polar (Low Earth) orbit corresponding to local 'morning' while the US is responsible for 'afternoon' coverage. The series will provide data for both operational meteorology and climate studies. The combination of instruments on board Metop has remote sensing capabilities to observe the Earth by day and night, as well as under cloudy conditions.
The EPS Space Segment includes three successive Metop satellites and is being developed and procured on the basis of cooperation between EUMETSAT and the European Space Agency (ESA). A cooperative agreement with CNES covers the development of the Infrared Atmospheric Sounding Interferometer (IASI).
EUMETSAT is responsible for the definition of the overall EPS system, the development and operations of the ground segment, and for the operation of the whole system.