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AP Index

Data provided by  National Oceanic and Atmospheric Administration

Planetary Amplitude index - Bartels 1951. The a-index ranges from 0 to 400 and represents a K-value converted to a linear scale in gammas (nanoTeslas)--a scale that measures equivalent disturbance am- plitude of a station at which K=9 has a lower limit of 400 gammas.

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Updated: 2024-02-22
Metadata Last Updated: 2025-11-19T15:45:16.931Z
Date Created: N/A
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Dataset Owner: N/A

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Title AP Index
Description Planetary Amplitude index - Bartels 1951. The a-index ranges from 0 to 400 and represents a K-value converted to a linear scale in gammas (nanoTeslas)--a scale that measures equivalent disturbance am- plitude of a station at which K=9 has a lower limit of 400 gammas.
Modified 2025-11-19T15:45:16.931Z
Publisher Name N/A
Contact N/A
Keywords Geomagnetism; Space Physics; Climatology, Solid Earth Geophysics , 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 
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