Auroral zone thermospheric dynamics using Fabry-Perot interferometric measurements of the O1 15867 K emission

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1985

OSTI ID:5572887

Sica, R J

Forty-four nights of thermospheric neutral wind and temperature measurements were obtained from College, Alaska (65/sup 0/ invariant latitude) during solar maximum using a ground-based Fabry-Perot interferometer. When averaged by increasing geomagnetic activity, the wind exhibits two main features. First, the general flow pattern poleward and westward in the evening, changing to southward and eastward in the morning, persists with increasing activity. The flow velocity increases and the change in direction occurs earlier in magnetic local time as the geomagnetic activity increases. Second, as the activity increases, the meridional wind pattern shifts equatorward with the auroral oval. Consequently, the low geomagnetic activity average wind pattern in the north is similar to the moderate activity average pattern in the south. The average thermospheric temperature is governed by the geomagnetic activity and by the previous day's 10.7 cm solar flux. The increase in temperature with solar flux is about the same as with auroral activity (approx. = 225/sup 0/K). The dynamical behavior on individual nights highlights the importance of local auroral substorms, which can cause large deviations from both global models and the observed averages. Coupling between the E and F regions is inferred by comparing the bulk motion of the optical aurora and the observed wind. Westward-drifting auroral forms accompany the westward evening zonal wind.

• Research Organization: Alaska Univ., Fairbanks (USA)
• OSTI ID: 5572887
• 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
DYNAMICS
EARTH ATMOSPHERE
GEOMAGNETIC FIELD
MAGNETIC FIELDS
MAGNETIC STORMS
MECHANICS
SOLAR ACTIVITY
THERMOSPHERE