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Dataset Overview | National Centers for Environmental Information (NCEI)

Solar Features - Solar Flares

browse graphicBrowse image of sun from the NOAA Solar X-ray Imager (SXI) for 07-March-2012 with the X-ray Sensor (XRS) superimposed below the image.
A solar flare is a short-lived sudden increase in the intensity of radiation emitted in the neighborhood of sunspots. For many years it was best monitored in the H-alpha wavelength and occurs in the chromosphere, though occasionally white light flares are seen in the photosphere. In modern times the solar X-ray wavelengths are monitored via satellite for solar flares. Flares are characterized by a rise time of the order of minutes and a decay time of the order of tens of minutes. The total energy expended in a typical flare is about 1030 ergs; the magnetic field is extraordinarily high reaching values of 100 to 10,000 gauss. Optical flares in H-alpha are usually accompanied by radio and X-ray bursts and occasionally by high-energy particle emissions.
The optical brightness and size of the flare are indicated by a two-character code called "importance." The first character, a number from 1 to 4, indicates the apparent area. For areas of less than 1, an "S" is used to designate a subflare. The second character indicates relative brilliance: B for bright, N for normal and F for faint. A general discussion of solar flares is found in Svestka [1976]. The NOAA National Centers for Environmental Information (formerly NGDC) holds archives for about 80 stations, covering the period 1938 to the present. Currently 5 stations send their data to NGDC Boulder on a routine monthly basis -- the current main observing emphasis for Space Weather has transitioned to Coronal Mass Ejections (CMEs) which directly impact the Earth's geomagnetic field. Solar flares impact the Earth's upper atmosphere and can eject high energy particles that can cause satellite failures. The flare reports were processed and published in the monthly report "Solar-Geophysical Data" and in a different format in the IAU "Quarterly Bulletin on Solar Activity."
Cite this dataset when used as a source.
  • solarFeatures
gov.noaa.ngdc.stp.solar:solar-features_solar-flares
Distribution Formats
  • pdf
    • File Specification: Most data provided as ASCII text files.
  • txt
    • File Specification: Some data provide in American Standard Code for Information Interchange (ASCII) text format.
  • TBD
    • File Specification: Some data provided in non-standard formats
Distributor William Denig
DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
(303) 497-6323
solar.ngdc@noaa.gov
Dataset Point of Contact William Denig
DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
(303) 497-6323
solar.ngdc@noaa.gov
Coverage Description Data acquired from NOAA observing systems plus other datasets provided through the World Data Service for Geophysics, Boulder.
Time Period 1938-01-01 to Present
Spatial Bounding Box Coordinates
West: -180
East: 180
South: -90
North: 90
Spatial Coverage Map
Documentation links not available.
Publication Dates
  • publication: 2014-08-10
Dataset Progress Status Under development - data is currently in the process of being created
Data Update Frequency Annually
Supplemental Information
Collection consists of tabular lists and information related to solar flares.
Purpose To provide scientific data stewardship of solar-terrestrial datasets in compliance with NOAA Administrative Order (NAO) 212-15, "Management of Environmental and Geospatial Data and Information", dated 04 Nov 10. Scientific Data Stewardship includes the Archive, Access, and Assessment (AAA) of operational and related solar and space environmental datasets.
Originators
  • These data were acquired from various providers. Please reference the recommended citation text within the documentation section associated with each dataset. Overall Scientific Data Stewardship provided by the National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce.
Publishers
  • NOAA National Centers for Environmental Information
Acknowledgments
  • Data access provided by the NOAA Solar and Terrestrial Physics Division. Numerous solar observatories have contributed to this collection - please refer to the Lineage section of this metadata record.
Theme keywords NASA/GCMD Earth Science Keywords; Olsen, L.M., G. Major, K. Shein, J. Scialdone, R. Vogel, S. Leicester, H. Weir, S. Ritz, T. Stevens, M. Meaux, C.Solomon, R. Bilodeau, M. Holland, T. Northcutt, R. A. Restrepo, 2007 . NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 6.0.0.0.0.
  • Sun-Earth Interactions > Solar Activity > Flares
Data Center keywords Global Change Master Directory (GCMD) Data Center Keywords
  • DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
  • DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce
Platform keywords NASA/GCMD Platform Keywords; Olsen, L.M., G. Major, K. Shein, J. Scialdone, R. Vogel, S. Leicester, H. Weir, S. Ritz, T. Stevens, M. Meaux, C.Solomon, R. Bilodeau, M. Holland, T. Northcutt, R. A. Restrepo, 2007 . NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 6.0.0.0.0.
  • Solar/Space Observation Satellites
Instrument keywords NASA/GCMD Instrument Keywords; Olsen, L.M., G. Major, K. Shein, J. Scialdone, R. Vogel, S. Leicester, H. Weir, S. Ritz, T. Stevens, M. Meaux, C.Solomon, R. Bilodeau, M. Holland, T. Northcutt, R. A. Restrepo, 2007 . NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 6.0.0.0.0.
  • Solar/Space Observing Instruments > Photon/Optical Detectors
  • Solar/Space Observing Instruments > Photon/Optical Detectors > Telescopes
  • Solar/Space Observing Instruments > Photon/Optical Detectors > Telescopes > > SOLAR TELESCOPES
Place keywords NASA/GCMD Location Keywords; Olsen, L.M., G. Major, K. Shein, J. Scialdone, R. Vogel, S. Leicester, H. Weir, S. Ritz, T. Stevens, M. Meaux, C.Solomon, R. Bilodeau, M. Holland, T. Northcutt, R. A. Restrepo, 2007 . NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 6.0.0.0.0.
  • > Solar Region > Photosphere
  • Space > Solar Region > Chromosphere
  • Space > Solar Region > Corona
Project keywords Global Change Master Directory (GCMD) Project Keywords
  • ICSU-WDS > International Council for Science - World Data System
  • NOAA - Space Weather Program
Use Constraints
  • Access Constraints: None Use Constraints: None Distribution Liability: 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, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty.
Access Constraints
  • Access Constraints: None Use Constraints: None Distribution Liability: 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, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty.
Fees
  • Data can be downloaded free of charge.
Lineage information for: series
Lineage Statement Authoritative data provided by various institutions.
Processor
  • DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce
Source Datasets
  • Collection included as a part of the NGDC Official Archive.
    • Description of Source: The NOAA Solar and Terrestrial Physics Division is responsible for managing this collection.
    • Temporal extent used: 1938-01-01 to Present
  • Solar Flares: H-alpha
  • Solar Flares: Flare Patrol
  • Solar Flares: Flare Index
  • Solar Flares: X-rays
  • Solar Flares: SIDs
Lineage information for: repository
Processing Steps
  • 2015-04-22T00:00:00 - NOAA created the National Centers for Environmental Information (NCEI) by merging NOAA's National Climatic Data Center (NCDC), National Geophysical Data Center (NGDC), and National Oceanographic Data Center (NODC), including the National Coastal Data Development Center (NCDDC), per the Consolidated and Further Continuing Appropriations Act, 2015, Public Law 113-235. NCEI launched publicly on April 22, 2015.
Acquisition Information (collection)
Instrument
Platform
Last Modified: 2015-10-02
For questions about the information on this page, please email: solar.ngdc@noaa.gov