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    • AA Geomagnetic Activity Indices From Two Antipodal Observatories in Australia and England

    Metadata Updated: October 18, 2024

    The NOAA National Centers for Environmental Information (formerly National Geophysical Data Center) receives, on a monthly basis, indices that are based on the data from two approximately antipodal observatories in England and Australia. The AA-indices are available from 1868 to present.

    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.

    Downloads & Resources

    Dates

    Metadata Date September 18, 2015
    Metadata Created Date October 18, 2024
    Metadata Updated Date October 18, 2024
    Reference Date(s) January 1, 1968 (publication)
    Frequency Of Update NOT UPDATED

    Metadata Source

    Harvested from NGDC STP Indices

    Other Data Resources

    Graphic Preview

    Annual Sunspot and aa Numbers

    Additional Metadata

    Resource Type Dataset
    Metadata Date September 18, 2015
    Metadata Created Date October 18, 2024
    Metadata Updated Date October 18, 2024
    Reference Date(s) January 1, 1968 (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.ngdc.stp.indices:G00588
    Access Constraints 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 NOT UPDATED
    Graphic Preview Description Annual Sunspot and aa Numbers
    Graphic Preview File https://www.ngdc.noaa.gov/stp/GEOMAG/image/aassn07.jpg
    Graphic Preview Type jpg
    Harvest Object Id c74dca3f-bafb-46e3-beb5-6fcbac9a9942
    Harvest Source Id 8fcc91fb-3399-4b06-abea-b4dadb7df9b7
    Harvest Source Title NGDC STP Indices
    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, 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.
    Lineage
    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 completed
    Spatial Data Service Type
    Spatial Reference System
    Spatial Harvester True
    Temporal Extent Begin 1868-01-01

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