Mission Specification

metop-aThe Meteorological Operational satellite program (MetOp) launched its first polar orbiting satellite (MetOp-A) on October 19, 2006. On 17 September 2012, the follow-on MetOp-B was successfully launched into polar orbit, which is now in a co-planar orbit and nearly half an orbit out of phase with MetOp-A.
MetOp is the first in a series of European satellites dedicated to near-real-time operational meteorology observations. The MetOp mission is primarily a joint collaboration between ESA and EUMETSAT with additional assistance from CNES and NOAA. MetOp is in a sun-synchronous orbit, carrying a payload of 10 scientific instruments including NOAA’s well established Advanced Very High Resolution Radiometer (AVHRR) to measure sea surface temperature (SST) and the new European Advanced Scatterometer (ASCAT) to measure ocean surface wind vectors.
MetOp has a repeat period of 29 days/412 orbits and the local equator crossing time at the ascending node is 21 hours 30 minutes; a repeat orbit is almost reached every 5 days/71 orbits. The orbit period is approximately 101 minutes. Metop flies at a mean altitude of 817 km and has an orbit inclination of 98.7 degrees. The operational mission duration is expected to be 4.5 years.

Instrument Specification
  • Advanced Scatterometer (ASCAT) – An improved follow-on to ESA’s ERS-1 and ERS-2 scatterometer missions. Transmitting at of 5.255 GHz (C-band),six antennas provide twice the coverage of a single ERS scatterometer using a dual-swath fan-beam configuration. Its primary purpose is to provide all-weather ocean surface wind vector measurements over the ice-free global oceans.
  • Advanced Microwave Sounding Unit (AMSU) – NOAA’s passive multi-channel microwave radiometer designed to measure the scene radiance. Two AMSU units (A1 and A2) are aboard, and the data is used in conjunction with HIRS/4 to estimate the global atmospheric temperature and moisture profiles from the surface to the upper stratosphere.
  • Advanced Very High Resolution Radiometer (AVHRR/3) – NOAA’s 3rd generation passive radiometer measures the Earth’s surface radiance in six spectral bands ranging from 0.58 to 12.5 microns. Measurements provide daily and nighttime estimates of land and sea surface temperature, and radiance imaging can be use to show cloud, ice, snow, and vegetation cover.
  • Global Ozone Monitoring Experiment-2 (GOME-2) – ESA’s nadir-scanning ultraviolet and visible spectrometer measures light from the solar-illuminated Earth atmosphere (or a direct look at the Sun). The spectra are used to estimate the atmospheric content and profile of ozone, nitrogen dioxide, water vapor, oxygen/oxygen dimmer, bromine oxide, and other various gases.
  • Global navigation satellite systems radio occultation Receiver for Atmospheric Sounding (GRAS) – A Global Positioning Satellite (GPS) receiver operating as an atmospheric sounding instrument which provides at least 500 atmospheric sounding profiles of temperature and moisture each day using a process known as GPS radio occultation.
  • High Resolution Infrared Radiation Sounder (HIRS/4) – A 20-channel infrared radiometric sounder which is used in conjunction with the AMSU instruments to estimate the atmosphere’s vertical temperature and humidity profiles and the pressure of Earth’s surface up to an altitude of about 40 km. Data can also be used to estimate sea surface temperatures, total atmospheric ozone, precipitable water, cloud height, and surface albedo.
  • Infrared Atmospheric Sounding Interferometer (IASI) – A Fourier Transform Spectrometer with an imaging system. It is designed to measure the infrared spectrum emitted by the Earth and is stated to provide improved infrared soundings of temperature profiles in the troposphere and lower stratosphere, moisture profiles in the troposphere, and certain chemical compounds.
  • Microwave Humidity Sounder (MHS) – A five-channel, self-calibrating, total power, scanning microwave radiometer which provides information on surface radiation/temperature, atmospheric ice, cloud cover, precipitation, and humidity at various atmospheric levels.
  • Space Environment Monitor-2 (SEM-2) – NOAA’s spectrometer providing measurements of Earth’s radiation belts and charged particle fluxes at satellite altitude. It is used to provide awareness of solar and terrestrial anomalies and warnings of solar wind occurrences that may damage or impair satellite functionality.