The longitudinal polar cusp displacement from geomagnetic measurements in Antarctica

We used ULF geomagnetic field measurements in the Pc5 frequency range (1.7−7 mHz) at two Antarctic stations to statistically investigate the longitudinal location of the polar cusp. The two stations are located at the same geomagnetic latitude, ~80° S (just poleward of the cusp), and are separated b...

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Bibliographic Details
Published in:Annals of Geophysics
Main Authors: Marzocchetti, Martina, Lepidi, Stefania, Francia, Patrizia, Cafarella, Lili, Di Mauro, Domenico
Other Authors: Istituto Nazionale di Geofisica e Vulcanologia (INGV), Sezione Roma2, Roma, Italia, #PLACEHOLDER_PARENT_METADATA_VALUE#
Format: Article in Journal/Newspaper
Language:English
Published: 2019
Subjects:
Online Access:http://hdl.handle.net/2122/13027
https://doi.org/10.4401/ag-7779
Description
Summary:We used ULF geomagnetic field measurements in the Pc5 frequency range (1.7−7 mHz) at two Antarctic stations to statistically investigate the longitudinal location of the polar cusp. The two stations are located at the same geomagnetic latitude, ~80° S (just poleward of the cusp), and are separated by one hour in magnetic local time. Since at each station the Pc5 power maximizes when the station approaches the cusp, the comparison between their Pc5 power allows to estimate the longitudinal position of the cusp and to examine its movements. We found that there is a displacement of the cusp depending on interplanetary conditions; in particular, the cusp shifts to later hours for negative values of the interplanetary magnetic field and solar wind velocity east−west components (By and Vy), while moves to earlier hours for positive values of Vy. Conversely, no dependence of the cusp longitudinal position on positive By values nor on the interplanetary magnetic field north−south component (Bz) emerges. Published Gm 446 1A. Geomagnetismo e Paleomagnetismo JCR Journal