Effects of thermospheric motions on the polar wind: A time-dependent numerical study

Journal Article · Fri May 01 04:00:00 EDT 1987 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/JA092iA05p04725· OSTI ID:5398654

Gombosi, T I; Killeen, T L ^[1]

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1. Univ. of Michigan, Ann Arbor (United States)

This paper presents the results of a numerical study investigating the effects of low-altitude short-duration plasma heating episodes (such as horizontal frictional heating) on transient heavy ion outflows from the polar ionosphere using a time-dependent model. In a previous set of calculations, where the effects of high-altitude transient heat sources were investigated, the low-altitude neutral atmosphere (z < 800 km) acted as a very efficient heat sink, absorbing most of the energy conducted to this region and thus preventing large differences between the ion and neutral temperatures. On purpose of the present study was to investigate whether realistic, specified low-altitude frictional heating rates, based on published experimental data, can result in elevated ion temperatures and lift a part of the heavy ion population over the gravitational barrier before the extra energy is lost to the neutral atmosphere. In the model calculations the specified heating generated an upflowing O{sup +} disturbance (with a normalized peak flux of {approximately}10{sup 8} cm{sup {minus}2} s{sup {minus}1}) moving upward along the open magnetic field line with a velocity of {approximately}2 km/s. The spatial extent of the disturbance was approximately equal to the disturbance velocity times the duration of the heat source. The model results provide a possible mechanism to explain recent European Incoherent Scatter observations of high-latitude O{sup +} upwellings.

• OSTI ID: 5398654
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 92:A5; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

661320* -- Auroral
Ionospheric
&amp; Magnetospheric Phenomena-- (1992-)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CATIONS
CHARGED PARTICLES
EARTH ATMOSPHERE
GEOMAGNETIC FIELD
HEATING
ION DRIFT
ION TEMPERATURE
IONOSPHERE
IONS
MAGNETIC FIELDS
MASS TRANSFER
MATHEMATICAL MODELS
MATHEMATICS
NUMERICAL ANALYSIS
OXYGEN IONS
PLANETARY IONOSPHERES
PLASMA DRIFT
PLASMA HEATING
POLAR REGIONS
THERMOSPHERE
TIME DEPENDENCE