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Reflection of the Geomagnetic Activity Occurring in the Earth's Northern and Southern Hemisphere (KM, KN, KS Indices)

Published by NOAA National Centers for Environmental Information | National Oceanic and Atmospheric Administration, Department of Commerce | Metadata Last Checked: December 19, 2025 | Last Modified: 1959-01-01T00:00:00.000+00:00
The NOAA National Centers for Environmental Information (formerly National Geophysical Data Center) receives on a monthly basis, the KM, KN, KS indices from Institue De Physique Du Globe, Paris, France. These data are available from 1959 to present. The KN and KS are planetary indices which have been derived using data obtained by northern and southern hemisphere observatories, respectively. KM is mean value and is usually very close in magnitude to KP. These indices reflect the geomagnetic activity occurring in the Earth's northern and southern hemispheres.

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