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Geomagnetic Kn, Ks, Km Indices

Metadata Updated: September 16, 2022

A full description of the indices Kn, Ks, Km is given in a monography,"Indices Kn, Ks et Km, 1964-1967", edited in 1968 by the Centre National de la Recherche Scientifique, 15 quai Anatole, France, 75007 Paris, which contains these indices for 2964-1967 while the International Association of Geomagnetism and Aeronony (IAGA) Bulletin NO. 39 contains those for 1959-1963. Yearly computations of these data are published in the series of IAGA Bulletin No.32. All of them are available in digital form at the appropriate World Data Center. Briefly, the three-hourly indices Kn and Ks for the Northern and Southern Hemispheres respectively are derived from the K indices of observatories approximately well distributed in latitude and in longitude. The indices are standardized according to the distances of the stations to the auroral zones. The stations are arranged in groups representing a longitude sector in one of the hemispheres (5 in the Northern Hemisphere, 4 in the Southern). The observatories currently in use are: MGD-Magadan, EYR-Eyrewell, PET-Petropavlovsk, LAU-Lauder, MMB-Memambetsu, CAN-Canberra, POD-Podkammenaya Tunguska, SVE-Sverdlovsk, GNA-Gnangara, NGK-Niemegk, KGL-Kerguelen, CZT-Crozet, HAD-Hartland, HER-Hermanus, OTT-Ottawa, AIA-Argentine Island, FRD-Fredericksburg, NEW-Newport, VIC-Victoria, TUC-Tucson The mean standardized K of each sector is converted into an equivalent amplitude and the weighted (in longitude) averages and these amplitudes are converted back into Kn and Ks. Km is derived in the same way from am, the average of an and as. Indices an, as and am are expressed in gammas (one gamma equals one nanoTesla) and correspond to the magnetic activity level (as it can be inferred from K indices 0 at an invariant magnetic latitude of 50 degrees. Indices Kn, Ks and Km are expressed in the same units as Kp. Values published in these reports are only provisional because in some months all observatories used in each longitude sector have not sent K indices at the right time and because K indices of Antarctic Stations have be rescaled at the end of each wintering.

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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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Dates

Metadata Date September 18, 2015
Metadata Created Date September 16, 2022
Metadata Updated Date September 16, 2022
Reference Date(s) May 13, 1998 (publication)
Frequency Of Update monthly

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) May 13, 1998 (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:G01185
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 monthly
Harvest Object Id 5bb9cc7c-32ae-459c-a092-f7c82c2698a9
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 1983-01-01

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