Recorded presentation3.4
Momentum budget of the migrating diurnal tide
Ruth S. Lieberman, Northwest Research Associates, Colorado Research Associates Division, Boulder, CO; and D. Riggin, D. A. Ortland, and Q. Wu
The migrating diurnal tide in the mesosphere and lower
thermosphere is examined in SABER temperature and
geopotential, and concurrent TIDI horizontal winds.
Amplitudes generally maximize near the March equinox, and
minimize in August. Considerable year-to-year variations
are noted between 2004 and 2007, with the weakest amplitudes
seen in 2005. Simultaneous retrievals of diurnal winds,
temperature, and geopotential allow the diurnal vertical
wind to be inferred using the adiabatic and the
kinematic methods. We also compute the momentum
budget of the diurnal zonal wind. Advection of zonal
momentum by the diurnal meridional wind is a
key nonclassical effect. A net zonal momentum
residual is present during all seasons, with an average
amplitude near 60 m/s/day.
Session 3, Satellite Observations of the Middle Atmosphere I
Monday, 8 June 2009, 1:50 PM-3:30 PM, Pinnacle A
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