Upper atmosphere temperature variability from 100 to 280 km over a full solar cycle - the WINDII perspective

The Wind Imaging Interferometer (WINDII) flown on the Upper Atmosphere Research Satellite (UARS) provides a means of examining variability in the thermospheric temperature and density over the altitude range from 70 to 300 km over a period of more than 10 years (from 1991 to 2003) through observations of Rayleigh scattering temperatures (70-95 km), Doppler temperatures (90-300 km), and atomic oxygen airglow emissions (90-300 km). The observation period encompasses two solar maxima (1992-1993 and 2000-2001) and one solar minimum (1996-1997). The original WINDII dataset (1991-1997) was recently extended to 2003 with observations not analysed before thus bridging the gap between the UARS and TIMED satellite missions and providing a means for examining thermospheric parameter variability over two solar cycles. The variability of airglow Doppler temperature with height from above the mesosphere to 300 km will be examined for solar maximum and minimum conditions, with an emphasis on the 100-160 km height regime where significant coupling between the lower and the upper thermosphere exists; neutral density and temperature are the key to understanding the upper atmosphere thermal response to perturbations from below. Some preliminary results from this study will be presented and discussed.