HR: 0830h
AN: SA21B-0072 [PDF]
TI: Effect of the Theta Aurora on the Polar Thermosphere
AU: * Demars, H G
EM: howard@aros.net
AF: Center for Atmospheric and Space Sciences, Utah State University
4405 Old Main Hill, Logan, UT 84322-4405 United States
AU: Schunk, R W
EM: schunk@cc.usu.edu
AF: Center for Atmospheric and Space Sciences, Utah State University
4405 Old Main Hill, Logan, UT 84322-4405 United States
AB:
The theta aurora is characterized by a transpolar auroral arc, connecting the dayside to the nightside auroral oval A
high-resolution time-dependent model of the global thermosphere is used to estimate the effects of this transpolar arc on the
polar thermosphere. A background ionospheric model is assumed, and a simple but physically plausible representation of the
ionospheric conditions within the transpolar arc is "superimposed" on the background ionosphere. The thermospheric model is
then solved both with and without the imposed transpolar arc to determine the arc's effects on the neutral gas. In
particular, percentage changes in thermospheric mass density and temperature are computed. These percentage differences are
significant and are seen to vary systematically with the level of the ionospheric density enhancement within the arc. A
strong dependence on solar activity level is also noted.
DE: 2407 Auroral ionosphere (2704)
DE: 2427 Ionosphere/atmosphere interactions (0335)
DE: 2435 Ionospheric disturbances
SC: SPA - Aeronomy [SA]
MN: 2003 Fall Meeting