Cross-polar cap potential difference, auroral electrojet indices, and solar wind parameters

Journal Article · Sat Feb 01 00:00:00 EST 1992 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/91JA02432· OSTI ID:5361755

Ahn, B H ^[1]; Kamide, Y ^[2]; Kroehl, H W; Gorney, D J ^[3]

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1. Kyungpook National Univ., Taegu (Korea) Univ. of Colorado, Boulder (United States)
2. Kyoto Sangyo Univ., (Japan)
3. Aerospace Corp., Los Angeles, CA (United States)

The cross-polar cap potential difference {Phi} (KRM) is estimated from ground magnetic perturbation data through the magnetometer inversion method of Kamide, Richmond, and Matsushita (FRM), combined with an empirical ionospheric conductance distribution estimated from the DMSP X ray image data. A significant correlation is found between {Phi} (KRM) and the AE(12) index. {Phi} (KRM) is then compared with the potential difference estimated from a more direct method of the satellite electric field measurements and also with {Phi}(IMF) is found to be linearly correlated with {Phi} (IMF) based on solar wind parameters. {Phi} IMF is found to be linearly correlated with {Phi}(KRM), as {Phi}(IMF) = 29.8 + 0.999 {Phi} (KRM), with the highest correlation obtained for a 40-min lag in the interplanetary magnetic field (IMF). Note that {Phi}(IMF) is systematically larger than {Phi} (KRM) by 30 kV, suggesting the possibility that the theoretical method overestimates the cross-polar cap potential difference. During steady southward IMF periods were steady {Phi} (IMF) variations are expected, significant fluctuations in calculated {Phi} (KRM) values are obtained. Since the decrease in {Phi} (KRM) is closely associated with enhancements in auroral particle precipitation during these periods, a highly correlative relation between {Phi} (IMF) and {Phi} (KRM) cannot be deduced unless the phases of substorms are taken into account. The overall high correlation between them, however, supports the view expressed by Wolf et al. (1986) that directly driven processes are more important than unloading processes during disturbed periods.

• OSTI ID: 5361755
• Journal Information: Journal of Geophysical Research; (United States), Vol. 97:A2; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
EARTH MAGNETOSPHERE
SOLAR WIND
POLAR REGIONS
ELECTRIC POTENTIAL
INTERACTIONS
AURORAE
CALCULATION METHODS
COMPARATIVE EVALUATIONS
CONVECTION
CORRELATIONS
ELECTRIC FIELDS
ELECTROJETS
CURRENTS
EARTH ATMOSPHERE
ELECTRIC CURRENTS
ENERGY TRANSFER
EVALUATION
HEAT TRANSFER
MASS TRANSFER
SOLAR ACTIVITY
661320* - Auroral
Ionospheric
& Magnetospheric Phenomena- (1992-)