Field-aligned current signatures during the March 13-14, 1989, great magnetic storm

Journal Article · Wed Jul 01 00:00:00 EDT 1992 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/92JA00171· OSTI ID:7258997

Fujii, R ^[1]; Fukunishi, H ^[2]; Kokubun, S ^[3]; Sugiura, M ^[4]; Tohyama, F ^[5]; Hayakawa, H; Tsuruda, K ^[6]; Okada, T ^[7]

---

1. National Institute of Polar Research, Tokyo (Japan)
2. Tohoku Univ., Sendai (Japan)
3. Univ. of Tokyo (Japan)
4. Tokai Univ., Tokyo (Japan)
5. Tokai Univ., Kanagawa (Japan)
6. Institute of Space and Astronautical Science, Kanagawa (Japan)
7. Toyama Prefectural Univ. (Japan)

Characteristics of field-aligned currents (FACs) in the evening and morning regions during the March 13-14, 1989, great magnetic storm have been determined using magnetic and electric field data obtained from the EXOS D spacecraft. This storm began with an SSC at 0128 UT on March 13, and the second SSC occurred at 0747 UT on the same day. The storm continued until March 14. The equatorward boundary of the FAC region began to move equatorward right after the first SSC in both the evening and morning sectors, but the poleward boundary did not immediately respond to the SSC. The equatorward boundary of the FAC system reached as low as below 48{degree} invariant latitude, which corresponds to L = 2.2, and the latitudinal width of the FAC region increased greatly, particularly in the morning sector ({approximately}33{degree} in invariant latitude). In the evening sector the conventional current system characterized by a pair of upward region 1 and downward region 2 FACs changed into complicated patterns consisting of many pairs of upward and downward FACs with the development of the storm, particularly around 22 UT on March 13 when an intense eastward electrojet was observed as low as 50{degree} invariant latitude on the ground. In the morning sector an additional large-scale upward FAC was observed poleward of the conventional downward region 1 and upward region 2 FAC system throughout the storm. In addition, a pair of FACs with a narrow latitudinal width ({approximately}1.5{degree}) was observed at the poleward boundary of the extra upward FAC.

• OSTI ID: 7258997
• Journal Information: Journal of Geophysical Research; (United States), Vol. 97:A7; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
EARTH MAGNETOSPHERE
ELECTRIC CURRENTS
IONOSPHERE
MAGNETIC STORMS
AURORAL ZONES
ELECTROJETS
GEOMAGNETIC FIELD
INTERPLANETARY MAGNETIC FIELDS
LATITUDE EFFECT
SOLAR WIND
SUDDEN COMMENCEMENTS
CURRENTS
EARTH ATMOSPHERE
GEOGRAPHICAL VARIATIONS
MAGNETIC FIELDS
PLANETARY IONOSPHERES
SOLAR ACTIVITY
VARIATIONS
661320* - Auroral
Ionospheric
& Magnetospheric Phenomena- (1992-)