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    • K Indices of Magnetic Activity Relative to an assumed Quiet-day for each 3-Hour Period

    Metadata Updated: September 16, 2022

    The NOAA National Centers for Environmental Information (formerly National Geophysical Data Center) receives the K indices on a current basis from approximately 85 observatories. The K index is a quasi-logarithmic local index of the 3-hourly range in magnetic activity relative to an assumed quiet-day curve for the recording site. First introduced by J. Bartels in 1938, it consists of a single digit 0 through 9 for each 3-hourly interval. The K indices are received on a monthly basis from the various observatories and are available from 1938 to present. The NOAA National Centers for Environmental Information (formerly National Geophysical Data Center) also receives KP indices from the Institute for Geophysik in Gottingen, Germany on a monthly basis. The KP index is a planetary index based on the K index from 12 or 13 selected stations and has been derived routinely from 1932.

    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 September 16, 2022
    Metadata Updated Date September 16, 2022
    Reference Date(s) January 1, 1957 (publication)
    Frequency Of Update irregular

    Metadata Source

    Harvested from NGDC STP Indices

    Additional Metadata

    Resource Type Dataset
    Metadata Date September 18, 2015
    Metadata Created Date September 16, 2022
    Metadata Updated Date September 16, 2022
    Reference Date(s) January 1, 1957 (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:G00590
    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 irregular
    Harvest Object Id 0c65fbef-5826-4e90-bd02-68c723567945
    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.
    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 1938-01-01

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