HR: 11:05h
AN: SA22A-04    [Abstracts]
TI: Longitudinal Variability in the Geomagnetically Quiescent Ionosphere
AU: * Hagan, M E
EM: hagan@ucar.edu
AF: National Center for Atmospheric Research. High Altitude Observatory, P.O. Box 3000, Boulder, CO 80307-3000, United States
AU: Maute, A
EM: maute@ucar.edu
AF: National Center for Atmospheric Research. High Altitude Observatory, P.O. Box 3000, Boulder, CO 80307-3000, United States
AU: Roble, R G
EM: roble@ucar.edu
AF: National Center for Atmospheric Research. High Altitude Observatory, P.O. Box 3000, Boulder, CO 80307-3000, United States
AU: Richmond, A D
EM: richmond@ucar.edu
AF: National Center for Atmospheric Research. High Altitude Observatory, P.O. Box 3000, Boulder, CO 80307-3000, United States
AB: We report on the effects of nonmigrating tides on the Earth's upper atmosphere based upon calculations made with the National Center for Atmospheric Research (NCAR) thermosphere-ionosphere- mesosphere-electrodynamics general circulation model (TIME-GCM) and global-scale wave model (GSWM). We extend the results reported by Hagan et al. (2007) who demonstrated that longitude variations in IMAGE satellite airglow brightness measurements associated with equatorial ionization anomaly peak densities can be attributed to longitudinally variable nonmigrating zonal wind tides which modulate the E-region dynamo and produce electric field effects that map into the F-region aloft. We explore the local time, altitude and seasonal variability of these nonmigrating tidal components in the TIME-GCM along with viable sources of excitation, including latent heat release associated with raindrop formation in deep convective towers in the tropical troposphere as parameterized in the GSWM. We also assess the reliability of our TIME-GCM predictions via comparison with accessible observations of the quiescent ionosphere. Hagan, M.E., A. Maute, R. G. Roble, A. D. Richmond, T. J. Immel, and S. L. England, (2007), Connections between deep tropical clouds and the Earths ionosphere, Geophys. Res. Lett., in press.
DE: 2415 Equatorial ionosphere
DE: 2427 Ionosphere/atmosphere interactions (0335)
DE: 3319 General circulation (1223)
DE: 3389 Tides and planetary waves
SC: SPA-Aeronomy [SA]
MN: 2007 Fall Meeting