Terme préférentiel

am index

Description

am (type of index: K-derived planetary and hemispheric; time resolution: 3-hour (UT) interval; unit: nT; availability: from 1959 onwards) is derived from the K indices calculated at a network of 24 magnetic observatories situated close to 50° corrected geomagnetic latitude (in the subauroral zones) covering all longitudes. am was introduced to allow a characterization of global geomagnetic activity using a large set of stations representing all longitudes and possible hemispheric discrepancies. am and related derived geomagnetic indices (such as: an, as, Kpm, Am, An and As) are provided by the Ecole et Observatoire des Sciences de la Terre, Strasbourg, France. am time series is formally recognised and endorsed since 1969 by International Association of Geomagnetism and Aeronomy (IAGA).

https://service.poleterresolide.fr/voc/variable/V0010200