HR: 17:30h
AN: SA34A-07    [Abstracts]
TI: Observations and modeling of stratospheric warmings and mesospheric coolings by the TIMED/SABER instrument and the NOGAPS forecast system
AU: * Siskind, D E
EM: siskind@uap2.nrl.navy.mil
AF: Naval Research Laboratory, 4555 Overlook Ave SW, Washington, DC 20375 United States
AU: Coy, L
EM: coy@uap2.nrl.navy.mil
AF: Naval Research Laboratory, 4555 Overlook Ave SW, Washington, DC 20375 United States
AU: Eckermann, S D
EM: eckerman@uap2.nrl.navy.mil
AF: Naval Research Laboratory, 4555 Overlook Ave SW, Washington, DC 20375 United States
AU: Russell, J M
EM: James.Russell@hamptonu.edu
AF: Center for Atmospheric Sciences, Hampton University, Hampton, VA 23666 United States
AB: We used temperature data from the Sounding of the Atmosphere with Broadband Emission Radiometry (SABER) experiment on the TIMED satellite to quantify the connection between temperatures in the mesosphere and lower thermosphere with the stratosphere. Specifically, we studied three winter periods where stratospheric temperatures were dynamically disturbed: February 2002 in the Northern Hemisphere; August, 2002 in the Southern Hemisphere; and Jan/Feb 2003 in the Northern Hemisphere. The SABER temperatures show a clear signature of mesospheric coolings in concert with stratospheric warmings. Mesospheric temperatures between 0.7 mb and 0.01 mb show a clear and significant anticorrelation with stratospheric temperatures with no phase lag or lead. For pressures $<$ 0.01 mb, this anticorrelation breaks down suggesting that mesospheric cooling events do not extend to altitudes higher than 80 km. We have compared the August 2002 observations with hindcasts using the Navy Operational Global Atmospheric Prediction System (NOGAPS) which has been recently extended up to 85-100 km. Good agreement is seen between SABER and NOGAPS over a 5-10 day period, although the model appears to underestimate the depth of the mesospheric cooling. This likely suggests the need for greater gravity wave drag in the model. Finally, the lack of a clear correlation between stratospheric temperatures and those at 83-90 km suggests that measurements of the OH Meinel band temperatures at those altitudes may not be representative of the entire mesosphere.
DE: 3334 Middle atmosphere dynamics (0341, 0342)
DE: 3369 Thermospheric dynamics (0358)
DE: 0342 Middle atmosphere--energy deposition
SC: SPA-Aeronomy [SA]
MN: 2004 AGU Fall Meeting