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POES Space Environment Monitor, Energetic Particles

Metadata Updated: May 6, 2023

The TIROS/NOAA satellite series, also known as POES, is designed to meet the National Oceanic and Atmospheric Administration's need for operational, remote sensing products for numerical weather and space environment forecasts. The TIROS designation represents the experimental classification of a new instrument configuration while NOAA represents the operational classification. For January 1979 through present, the National Centers for Environmental Information (formerly National Geophysical Data Center) archive data from the POES Space Environment Monitor instrument. Subcomponents of the SEM include: HEPAD (High Energy Proton and Alpha Detector), MEPAD (Medium Energy) and TED (Total Energy) data from TIROS and NOAA satellites. The satellites are in sun-synchronous orbits at 850 kilometers altitude, an orbital period of 102 minutes and an inclination of 99 degrees. The orbital plane is tilted toward the sun in the Northern Hemisphere. Usually, two satellites are operational at all times.NOAA's Polar Orbiting Environmental Satellites (POES) (formerly known as TIROS for Television and InfraRed Observation Satellite) carry a suite of instruments that detect and monitor the influx of energetic ions and electrons into the atmosphere and the particle radiation environment at the altitude of the satellite. Both phenomena vary as a result of solar and geomagnetic activity. Beginning with the NOAA-15 satellite, an upgraded version of the Space Environment Monitor (SEM-2) is being flown. A number of SEM-2 instruments have been procured and it is anticipated that the SEM-2 instruments will be included on the NOAA/POES satellites until superceded by the NPOESS satellite program sometime after 2010.Because the SEM-2 instruments differ significantly from the earlier SEM-1, there has been a complete revision to the data processing and archiving process. A number of improvements have also been included. Among these are incorporating up-to-date satellite orbit information and magnetic field models in the calculation of various magnetic coordinates, and improved data quality control. The Total Energy Detector (TED) is designed to measure the energy flux carried by auroral particles, both positively charged ions (assumed here to be protons) and electrons, into the polar atmosphere. The magnitude and spatial extent of this energy flux are good measures of both the level of auroral activity and the atmospheric response to that energy input. The Medium Energy Proton and Electron Detector (MEPED) includes a set of solid-state energetic particle detectors that monitor the intensities of protons and electrons over a range extending from 30 keV to more than 200 MeV. Particles having those energies include the radiation belt (Van Allen belt) populations, the particles in energetic solar particle events (solar proton events), and the low energy portion of the galactic cosmic ray population. Enhanced fluxes of these particles entering the atmosphere can produce significant and widespread degradation in short-wave radio propagation; in extreme cases even radio blackouts. The energetic particles also contribute to astronaut radiation exposure, especially on high inclination orbit missions during energetic solar particle events.

Access & Use Information

License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Date January 12, 2023
Metadata Created Date May 6, 2023
Metadata Updated Date May 6, 2023
Reference Date(s) November 1, 1978 (publication)
Frequency Of Update monthly

Metadata Source

Harvested from NOS STP SEM

Additional Metadata

Resource Type Dataset
Metadata Date January 12, 2023
Metadata Created Date May 6, 2023
Metadata Updated Date May 6, 2023
Reference Date(s) November 1, 1978 (publication)
Responsible Party DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce (Point of Contact)
Contact Email
Guid gov.noaa.ncei:952891654707466
Access Constraints Cite as: National Oceanic and Atmospheric Administration (1978): POES Space Environment Monitor, Energetic Particles. National Geophysical Data Center, NOAA. doi:10.7289/V5JS9NC6 [access date], Use Constraints: None, Access Constraints: No Constraints
Bbox East Long 180.000000
Bbox North Lat 90.000000
Bbox South Lat -90.000000
Bbox West Long -180.000000
Coupled Resource
Frequency Of Update monthly
Harvest Object Id c6bcfa64-db35-417a-b81a-aa61b6ad9715
Harvest Source Id ae3ccab3-178a-4cd0-823c-4e66331291fd
Harvest Source Title NOS STP SEM
Licence While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by any errors or omissions in the data.
Metadata Language eng; USA
Metadata Type geospatial
Old Spatial {"type": "Polygon", "coordinates": [[[-180.0, -90.0], [180.0, -90.0], [180.0, 90.0], [-180.0, 90.0], [-180.0, -90.0]]]}
Progress underDevelopment
Spatial Data Service Type
Spatial Reference System
Spatial Harvester True
Temporal Extent Begin 1978-11-01

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