HR: 17:15h
AN: SA32B-06 [PDF]
TI: Effects of Geomagnetic Storms and Sudden Stratospheric Warmings on Mesosphere and Lower Thermosphere
Winds
AU: * Wu, Q
EM: qwu@ucar.edu
AF: National Center for Atmospheric Research, 3450 Mitchell La., Boulder, CO 80301 United States
AU: Gablehouse, R D
EM: rdg@ucar.edu
AF: National Center for Atmospheric Research, 3450 Mitchell La., Boulder, CO 80301 United States
AU: Gell, D A
EM: gellda@umich.edu
AF: The University of Michigan, 2455 Hayward, Ann Arbor, MI 48109 United States
AU: Johnson, R M
EM: rmjohnsn@ucar.edu
AF: National Center for Atmospheric Research, 3450 Mitchell La., Boulder, CO 80301 United States
AU: Kafkalidis, J F
EM: juliek@umich.edu
AF: The University of Michigan, 2455 Hayward, Ann Arbor, MI 48109 United States
AU: Killeen, T L
EM: killeen@ucar.edu
AF: National Center for Atmospheric Research, 3450 Mitchell La., Boulder, CO 80301 United States
AU: Niciejewski, R J
EM: niciejew@umich.edu
AF: The University of Michigan, 2455 Hayward, Ann Arbor, MI 48109 United States
AU: Ortland, D A
EM: ortland@nwra.com
AF: Northwest Research Associates, P.O. Box 3027, Bellevue, WA 98009 United States
AU: Skinner, W R
EM: wskinner@umich.edu
AF: The University of Michigan, 2455 Hayward, Ann Arbor, MI 48109 United States
AU: Solomon, S C
EM: stans@ucar.edu
AF: National Center for Atmospheric Research, 3450 Mitchell La., Boulder, CO 80301 United States
AB:
Neutral winds in the MLT region are affected by dynamical influences from above and below. This is particular true at high
latitudes, where solar forcing of the migrating tide may be smaller but other forcings play a big role. During geomagnetic
storms, MLT neutral winds can be driven by magnetospheric convection through ion-neutral interactions. This is imparted onto
the ionosphere as a cross polar cap potential forming an anti-sunward two-cell ion convection pattern which in turn drives
the neutral winds in the polar MLT region. The question has always been how deep into the atmosphere the ion drift can
affect the neutral wind. Scarcity of high-latitude data has hampered further understanding of the problem. Also, in the
winter polar regions, the stratosphere from time to time experiences sudden warming events. While it is generally understood
that these warmings are caused by troposphere planetary wave activity, there are still many unknown aspects to their
excitation and propagation. There are also changes in the MLT region associated with these warming events. Moreover, this
phenomena, although usually confined to the northern hemisphere, occurred in the southern hemisphere in 2002. We will use
TIDI data to examine MLT neutral winds during the recent geomagnetic storm events in 2002 and 2003, and present data during
the recent 2002 southern hemisphere warming event.
DE: 0310 Airglow and aurora
DE: 3332 Mesospheric dynamics
DE: 3369 Thermospheric dynamics (0358)
SC: SPA - Aeronomy [SA]
MN: 2003 Fall Meeting