Saturation of the auroral electrojet current and the polar cap potential

Journal Article · Thu Nov 01 04:00:00 EST 1990 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/JA095iA11p18981· OSTI ID:5103002

Weimer, D R; Reinleitner, L A; Kan, J R; Zhu, L; Akasofu, S I ^[1]

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1. Univ. of Alaska, Fairbanks (United States)

It is shown that the auroral electrojet index AE tends to saturate, or approach a limiting value, for large southward interplanetary magnetic field, namely, B{sub Z} < {minus}15 nT. The saturation also occurs during individual major geomagnetic storms. The saturation of AE is the result of a saturation in the polar cap potential drop. The polar cap potential has a limiting value due to the nonlinear nature of the magnetosphere-ionosphere (M-I) coupling. Results of a M-I coupling model show that the saturation level of the polar cap potential is lowered as the diffuse auroral conductance increases. The data presented also show an increase in AE for large B{sub Z} values, indicating increased auroral activity for B{sub Z} > 20 nT.

• OSTI ID: 5103002
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 95:A11; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
&amp; Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CURRENTS
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
ELECTRIC CURRENTS
ELECTRIC POTENTIAL
ELECTROJETS
INTERACTIONS
INTERPLANETARY MAGNETIC FIELDS
IONOSPHERE
LIMITING VALUES
MAGNETIC FIELDS
MAGNETIC STORMS
MATHEMATICAL MODELS
PLANETARY IONOSPHERES
POLAR REGIONS
SATURATION