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Read Full Article (file size: 495418 bytes) Cited by
GEOPHYSICAL RESEARCH LETTERS,
VOL. 34,
L16101,
doi:10.1029/2007GL030175,
2007
On the cause of IMF By related mid- and low latitude magnetic disturbances
S. Vennerstrom
Danish National Space Center, Technical University of Denmark, Copenhagen, Denmark
F. Christiansen
Danish National Space Center, Technical University of Denmark, Copenhagen, Denmark
N. Olsen
Danish National Space Center, Technical University of Denmark, Copenhagen, Denmark
T. Moretto
Geosciences Directorate, National Science Foundation, Washington, D.C., USA
Abstract
An analysis of the effect of the IMF B y on near-Earth low and mid-latitude magnetic disturbances is presented. In particular the contribution from field-aligned
currents (FACs) connected to the polar regions is investigated. Based on statistically determined high-latitude FAC patterns
for various Interplanetary Magnetic Field (IMF) directions, we estimate the FAC contribution to the mid- and low latitude
magnetic disturbance and its dependence on the IMF. The estimated perturbations are compared with observations from the ground
and from the low-altitude polar orbiting satellite Oersted. It is found that the long-distance effect of the high-latitude
FACs constitute the major source to IMF B y and B z related magnetic east-west disturbances at mid- and low latitudes.
Received 27
March
2007;
accepted 19
June
2007;
published 16
August
2007.
Keywords: field-aligned currents;
IMF By;
low latitude perturbation.
Index Terms: 2721 Magnetospheric Physics: Field-aligned currents and current systems (2409); 1541 Geomagnetism and Paleomagnetism: Satellite magnetics: main field, crustal field, external field; 2784 Magnetospheric Physics: Solar wind/magnetosphere interactions; 2134 Interplanetary Physics: Interplanetary magnetic fields; 1650 Global Change: Solar variability (7537).
Read Full Article (file size: 495418 bytes) Cited by
Citation: Vennerstrom, S., F. Christiansen, N. Olsen, and T. Moretto
(2007),
On the cause of IMF By related mid- and low latitude magnetic disturbances,
Geophys. Res. Lett.,
34,
L16101,
doi:10.1029/2007GL030175.
Copyright 2007 by the American Geophysical Union.
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