Wind measurements by the TIMED Doppler interferometer (TIDI)

Following launch of the NASA Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics (TIMED) satellite in December 2001, the TIMED Doppler Interferometer (TIDI) commenced measurements of the global wind field in the mesosphere and lower thermosphere. Using limb scans of airglow emissions through four orthogonally oriented telescopes, TIDI simultaneously measures the neutral winds on two sides of the spacecraft. The primary measurements during TIMED early scientific operations are of the O_2 atmospheric bands. We will provide a brief description of the TIDI design, operational mode, and data analysis. Preliminary wind measurements in the polar mesopause region will be presented. Comparisons with mesospheric neutral winds measured by ground-based instruments will also be shown.