Products Derived From GUVI Auroral Data and Comparisons With Ground-Based Results From Poker Flat and Ft. Yukon, AK

The TIMED/GUVI experiment has been making routine auroral/airglow far ultraviolet measurements since January 2002. Routine auroral measurements at visible/near IR wavelengths from the ground sites identified in the title have also been made that offer the opportunity to compare derived data products when GUVI is making coincident observations. The products of interest are characteristic energy E_o and energy flux Q of precipitating electrons along with a scaling factor f_O of the atomic oxygen number density (referenced to a specific MSIS atmosphere) that addresses composition changes arising from auroral heating. Comparisons of these products will be presented as derived from TIMED/GUVI Earth-disk data (using the 135.6, LBH_S and LBH_L spectral channels) and coincident ground-based data recorded at Poker Flat and Ft. Yukon, AK (photometer zenith observations of OI 844.6 nm, OI 630.0 nm, N₂⁺ 427.8 nm, and N₂ 1PG 871.0 nm). Primary attention will be directed to GUVI data from a single orbit on April 17 2002 that recorded significant aurora emission over Alaska and elsewhere. The above products from coincident measurements of the two observing systems are in reasonable agreement and show significant reductions in f_O compared to undisturbed values. Similar comparisons will also be presented from other times during 2002 and 2003.