Magnetic impulses and associated optical signatures in the dayside aurora

Journal Article · Thu Feb 01 04:00:00 EST 1990 · Geophysical Research Letters (American Geophysical Union); (USA)

DOI:https://doi.org/10.1029/GL017i002p00131· OSTI ID:6281850

Mende, S B; Rairden, R L ^[1]; Lanzerotti, L J; Maclennan, C G ^[2]

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1. Lockheed Palo Alto Research Laboratories, CA (USA)
2. AT T Bell Laboratories, Murray Hill, NJ (USA)

The authors present five magnetic impulse events observed at South Pole and in the magnetically conjugate area at Iqaluit. The magnetic signatures recorded during these events appear to be similar to those discussed by several authors as possible ionospheric signatures of sporadic dayside reconnection via the flux transfer process. Coordinated ground-based image-intensified all sky camera data were acquired at South Pole during the events. The optical data show that prior to the onset of each of the events the dayside cusp aurora is several degrees poleward of the station, signifying event initiation on closed field lines. Overhead aurora appears at the onset of the magnetic event and precipitation seems to expand over a large region equatorward of the quiescent cusp aurora. As the event decays the aurora dies away and the quiescent dayside cusp aurora, in four out of five cases, returns poleward of the station. This morphology is inconsistent with the model in which the ground based signature of an FTE is caused by a field aligned current configuration moving over a ground station in the antisunward direction. The observations show temporal events which begin at or inside the boundary of closed field lines.

• OSTI ID: 6281850
• Journal Information: Geophysical Research Letters (American Geophysical Union); (USA), Journal Name: Geophysical Research Letters (American Geophysical Union); (USA) Vol. 17:2; ISSN GPRLA; ISSN 0094-8276
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AURORAE
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
IONOSPHERE
MAGNETIC FLUX
MAGNETIC RECONNECTION
MATHEMATICAL MODELS
MORPHOLOGY
PLANETARY IONOSPHERES
PLASMOIDS
POLAR REGIONS
SOLAR ACTIVITY
SOLAR WIND