POES

POES
Name	Polar Operational Environmental Satellites
Acronym	POES
Operator	National Oceanic and Atmospheric Administration / National Aeronautics and Space Administration
Status	Retired (last decommissioned)
First launch	1978
Last launch	2009
Spacecraft type	Meteorological polar-orbiting satellite
Orbit	Sun-synchronous, polar
Applications	Weather forecasting, climate monitoring, oceanography, atmospheric chemistry

POES The Polar Operational Environmental Satellites program provided a continuous series of polar-orbiting meteorological platforms supporting World Meteorological Organization requirements, National Weather Service forecasting, United States Department of Commerce environmental monitoring, and international data exchange. Sensors on the satellites delivered radiometric, sounder, and particle observations used by agencies such as European Organisation for the Exploitation of Meteorological Satellites, Japan Meteorological Agency, Canadian Meteorological Centre, and research institutions including National Center for Atmospheric Research, NASA Goddard Space Flight Center, and European Space Agency laboratories. POES data contributed to operational products at centers like the Met Office, Meteo-France, Deutscher Wetterdienst, and the Australian Bureau of Meteorology.

Overview

POES comprised a sequence of low-Earth, sun-synchronous polar platforms flown by NOAA in partnership with NASA and launched on vehicles such as the Delta II and Titan II. The constellation filled observational gaps between geostationary systems like GOES series and research missions such as Nimbus and TIROS. Instruments provided nadir and limb sounding compatible with datasets from ERS-2, ENVISAT, Suomi NPP, and MetOp series, enabling cross-calibration with missions from European Space Agency, JAXA, and Roscosmos. POES supported assimilation into numerical weather prediction systems run by ECMWF, NCEP, JMA, and regional centers.

Satellite Constellation and Instruments

Each POES platform carried a core payload that included the Advanced Very High Resolution Radiometer, the High Resolution Infrared Radiation Sounder, and space environment monitors. The Advanced Very High Resolution Radiometer provided visible and infrared imagery comparable to sensors on Landsat and MODIS, while the High Resolution Infrared Radiation Sounder offered sounding channels akin to AIRS and HIRS on other missions. Particle detectors and solar wind sensors mirrored capabilities in ACE and Geostationary Operational Environmental Satellite space weather instruments used by NOAA Space Weather Prediction Center. The constellation architecture allowed polar coverage complementary to Geostationary Operational Environmental Satellite footprints and synergistic observations with Aqua and Terra for diurnal cycle studies.

Data Products and Applications

POES delivered Level 1 calibrated radiances, Level 2 retrievals of temperature and humidity profiles, sea-surface temperature maps, ozone column estimates, and polar-orbiting cloud products. These inputs were crucial for operational centers including National Weather Service forecast models, seasonal prediction at IRI, and climate monitoring projects at NASA Langley Research Center. Applications ranged from tropical cyclone tracking used by Joint Typhoon Warning Center and National Hurricane Center to fisheries management supported by National Marine Fisheries Service and cryosphere analysis at University of Alaska Fairbanks. Data contributed to reanalysis efforts by ECMWF and CAMS and to studies published by groups at Scripps Institution of Oceanography and Woods Hole Oceanographic Institution.

History and Development

The program evolved from heritage platforms such as TIROS-N and experimental efforts at NASA Ames Research Center to fully operational series managed with launch support from Vandenberg Air Force Base and processing centers at NOAA Satellite Operations Facility. Key milestones involved sensor upgrades to match advances in meteorological sounding practice and coordination with international programs including Argos and International Satellite Cloud Climatology Project. Collaborations with research centers like NOAA Geophysical Fluid Dynamics Laboratory and Lamont–Doherty Earth Observatory informed retrieval algorithm improvements and intercomparison with missions such as ERS and ICESat.

Operational Management and Agencies

Day-to-day operations included satellite control, instrument commanding, data processing, and distribution managed by NOAA with partnerships from NASA for early development and calibration. Ground stations and command networks included facilities at Fairbanks International Airport tracking stations and global receiving arrays that interoperated with EUMETSAT infrastructure and the Global Telecommunications System. International data exchange followed protocols established by World Meteorological Organization and coordination with agencies like Japan Meteorological Agency and CONAE for shared polar environmental monitoring.

Performance, Limitations, and Calibration

POES provided reliable, long-term continuity but faced limitations in spatial resolution and revisit frequency relative to later missions such as MetOp and Suomi NPP. Calibration challenges required cross-comparisons with reference sensors on Aqua, Terra, and Landsat and vicarious calibration campaigns conducted by institutions like NOAA National Severe Storms Laboratory and NASA Jet Propulsion Laboratory. Instrument degradation, orbital drift, and inter-satellite biases were managed through intercalibration with NIST standards and community efforts involving GCOS and the International Ocean Colour Coordination Group.

Legacy and Successors

POES legacy includes foundational datasets that underpin modern reanalyses and operational observational networks; successors integrated POES capabilities into polar platforms like the MetOp series and the Joint Polar Satellite System. The transition involved coordination with EUMETSAT and NASA programs and ensured continuity for users including the World Meteorological Organization, International Civil Aviation Organization, and national meteorological services such as Servicio Meteorológico Nacional (Argentina), NOAA National Weather Service, and UK Met Office. Research institutions like Princeton University and Massachusetts Institute of Technology continue to exploit POES-era archives for climate and atmospheric chemistry studies.

Category:Earth observation satellites