Doppler temperatures from O(¹D) airglow in the daytime thermosphere as observed by the Wind Imaging Interferometer (WINDII) on the UARS satellite

C. Lathuillère (1) , W. A. Gault (2) , B. Lamballais (1) , Y. J. Rochon (3) , B. H. Solheim (2)

1 LPG - Laboratoire de Planétologie de Grenoble
2 CRESS - Centre for Research in Earth and Space Science [Toronto]
3 Meteorological Service of Canada

From 1992 to 1997, the WINDII interferometer on board the UARS satellite acquired a large set of thermospheric data from the O(¹D) and O(¹S) airglows. We report here for the first time on daytime O(¹D) Doppler temperatures obtained with version 5.11 of the WINDII data processing software. Using a statistical analysis of the temperatures independently measured by the two WINDII fields of view, we estimate that the temperature variations larger than 40 K can be considered as geophysical. Comparisons of WINDII temperatures measured during magnetically quiet days with temperatures obtained by the MSIS-90 and DTM-94 thermospheric models show a 100 K bias. We demonstrate, however, that the modeled temperature variations represent very well the mean temperature variation observed by WINDII over 4 years. We also show that the observed latitudinal/local time variation is in very good agreement with the two empirical models. Finally, the temperature variations during a magnetically disturbed day are found to be qualitatively well represented in form by the models, but largely underestimated. The presence of non-thermal atoms and instrument related issues are discussed as possible explanations for the 100 K bias between the WINDII Doppler temperatures and the empirical models.

Domaines: Océan, Atmosphère; Sciences de la Terre

C. Lathuillère, W. A. Gault, B. Lamballais, Y. J. Rochon, B. H. Solheim. Doppler temperatures from O(¹D) airglow in the daytime thermosphere as observed by the Wind Imaging Interferometer (WINDII) on the UARS satellite. Annales Geophysicae, 2002, 20 (2), pp.203-212. ⟨hal-00329200⟩