Lobe cell convection as a summer phenomenon

Journal Article · Sun Aug 01 04:00:00 EDT 1993 · Journal of Geophysical Research

DOI:https://doi.org/10.1029/93JA01037· OSTI ID:96491

Crooker, N U ^[1]; Rich, F J ^[2]

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1. Univ. of California, Los Angeles, CA (United States)
2. Hanscom Air Force Base, MA (United States)

Patterns of average potential over the high-latitude ionosphere in winter show that the dusk convection cell dominates the dawn cell, consistent with the presence of a day-night conductivity gradient, as predicted by a number of models. However, in the summer hemisphere, when IMF B{sub y} is strongly positive, the dusk cell so dominates the dawn cell that the latter nearly disappears; and when IMF B{sub y} is strongly negative, the cells are most nearly equal. The difference between winter and summer can be explained by the addition in summer of a single lobe cell, that is, a cell confined to open field lines, circulating within the dusk cell of the two-cell pattern when B{sub y} is positive and within the dawn cell when B{sub y} is negative. The result is consistent with predictions of the overdraped lobe model, that lobe cells occur in only one hemisphere at a time, and that their occurrence is controlled by dipole tilt. 35 refs., 3 figs.

• Sponsoring Organization: USDOE
• OSTI ID: 96491
• Journal Information: Journal of Geophysical Research, Journal Name: Journal of Geophysical Research Journal Issue: A8 Vol. 98; ISSN 0148-0227; ISSN JGREA2
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
CONVECTION
EARTH MAGNETOSPHERE
ELECTRIC CONDUCTIVITY
INTERPLANETARY MAGNETIC FIELDS
IONOSPHERE
SEASONAL VARIATIONS
SHOCK WAVES
SPATIAL DISTRIBUTION