Latitudinal Distributions of Auroral Zone Electric Fields and Ground Magnetic Perturbations and Their Response to Variations in the Interplanetary Magnetic Field

Journal Article · Mon May 01 04:00:00 EDT 1978 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA083iA05p02071· OSTI ID:6779564

Horwitz, J L; Doupnik, J R; Banks, P M; Kamide, Y; Akasofu, S

Chatanika observations of latitudinal distributions of convection electric fields (E/sub 1/) are compared with isointensity ..delta..H contours in latitude and time from the Alaskan magnetometer chain and with the north-south component of the interplanetary magnetic field (IMF B/sub z/m) from Imp-J. As expected, northward electric fields were generally observed within latitude and time regions where ..delta..H was positive, while southward electric fields were observed within negative ..delta..H regions. However, correlation between the magnitudes of the electric fields and of the ..delta..H perturbations was not strong, owing to variability in ionospheric conductivities produced by precipitation and solar illumination. In the midnight sector the northward-to-southward transition in the electric field and positive-to-negative ..delta..H transition were roughly collocated (to within 1 hour in local time) as signatures of the Harang discontinuity. The most important findings are that (1) southward (northward) IMF B/sub z/m transitions caused rapid equatorward (poleward) shifts of the electric field and ..delta..H patterns and (2) southward IMF B/sub z/ transitions, magnetospheric substorms, and local time transitions of the Harang discontinuity can all lead to northward-to-southward transitions of the electric field in the midnight sector. Due to the interlaced phasing of each of these three causal mechanisms a highly complex temporal pattern of electric fields results.

• Research Organization: Magnetospheric Physics Branch/ES53, Space Sciences Laboratory, Marshall Space Flight Center, Huntsville, Alabama 35812
• OSTI ID: 6779564
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 83:A5; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640201 -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
640203* -- Atmospheric Physics-- Magnetospheric Phenomena-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AURORAL OVAL
AURORAL ZONES
EARTH ATMOSPHERE
ELECTRIC FIELDS
GEOGRAPHICAL VARIATIONS
HARANG DISCONTINUITY
INCOHERENT SCATTERING
INTERPLANETARY MAGNETIC FIELDS
IONOSPHERE
LATITUDE EFFECT
MAGNETIC BAYS
MAGNETIC FIELDS
MEASURING INSTRUMENTS
RADAR
RANGE FINDERS
SCATTERING
VARIATIONS