TERRAPUB Earth, Planets and Space

Earth Planets Space, Vol. 61 (No. 4), pp. 447-453, 2009

Kelvin waves in stratosphere, mesosphere and lower thermosphere temperatures as observed by TIMED/SABER during 2002-2006

Jeffrey M. Forbes1, Xiaoli Zhang1, Scott E. Palo1, James Russell2, Christopher J. Mertens3, and Martin Mlynczak3

1Department of Aerospace Engineering Sciences, UCB 429, University of Colorado, Boulder, CO 80309-0429
2Center for Atmospheric Sciences, Hampton University, Hampton, VA 23668
3NASA Langley Research Center, Hampton, VA 23681-0001

(Received September 28, 2007; Revised March 18, 2008; Accepted March 25, 2008; Online published May 14, 2009)

Abstract: Temperature measurements from the SABER instrument on the TIMED spacecraft are used to elucidate the properties of Kelvin waves and other equatorial oscillations over the altitude range 20-120 km during 2002-2006. The dominant Kelvin waves transition from long periods (5-10 days) and short wavelengths (9-13 km) in the stratosphere, to shorter periods (2-3 days) and longer wavelengths (35-45 km) in the 80-120 km height region. Ultra-Fast Kelvin Waves (UFKW) with periods of 2.5-4.5 days intermittently exist at amplitudes of order 3-10 K between 80-120 km during all months of the year, with variability at periods typically in the 20-60 day range. An Intra-seasonal oscillation (ISO) of zonal mean temperatures also exists with periods 20-60 days that may be driven by Eliassen-Palm Flux Divergences (EPFD) due, at least in part, to UFKW and migrating diurnal tides.
Key words: SABER (Sounding the Atmosphere using Broadband Emissioni Radiometry), TIMED (Thermosphere Ionosphere Mesosphere Energetics Dynamics), Ultra-Fast Kelvin Waves (UFKW), Intra-seasonal oscillation (ISO), Eliassen-Palm Flux Divergences (EPFD).

Corresponding author E-mail: forbes@colorado.edu

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