HR: 1340h
AN: SA43A-1082    [Abstracts]
TI: Diurnal Nonmigrating Tides From TIDI Wind Measurements: Monthly Climatologies
AU: Oberheide, J
EM: joberh@uni-wuppertal.de
AF: Physics Department Wuppertal University , Gauss Strasse 20 , Wuppertal, D-42097 Germany
AU: * Hagan, M
EM: hagan@ucar.edu
AF: National Center for Atmospheric Research High Altitude Observatory, P.O. Box 3000, Boulder, CO 80307-3000 United States
AU: Wu, Q
EM: qwu@ucar.edu
AF: National Center for Atmospheric Research High Altitude Observatory, P.O. Box 3000, Boulder, CO 80307-3000 United States
AU: Killeen, T
EM: killeen@ucar.edu
AF: National Center for Atmospheric Research High Altitude Observatory, P.O. Box 3000, Boulder, CO 80307-3000 United States
AU: Roble, R
EM: roble@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 diurnal nonmigrating tides determined from TIMED Doppler Interferometer (TIDI) measurements of zonal and meridional winds in the mesosphere/lower thermosphere. We overview climatologies of monthly mean amplitudes and phases for seven tidal components (i.e., westward propagating wavenumbers 2, 3, and 4; the standing diurnal tide; and eastward propagating wavenumbers 1, 2, and 3) at altitudes between 85 and 105 km and latitudes between 45S and 45N. The observed seasonal variations agree well with 1991-1994 UARS results at 95 km. Comparisons between the TIDI results and global scale wave model (GSWM) and thermosphere-ionosphere-mesosphere-electrodynamcis general circulation model (TIME-GCM) tidal predictions indicate that the large eastward propagating wavenumber 3 amplitude is driven by tropical tropospheric latent heat release alone. In contrast, latent heating and planetary wave/migrating tidal interactions are equally important to westward 2 and standing diurnal tidal forcing. There is good quantitative agreement between TIDI and the model predictions during equinox, but they tend to underestimate the westward 2 and standing diurnal tide during solstice. Neither model reproduces the observed seasonal variations of the eastward propagating components.
DE: 3332 Mesospheric dynamics
DE: 3389 Tides and planetary waves
SC: SPA-Aeronomy [SA]
MN: Fall Meeting 2005