O/N2 changes during 1-4 October 2002 storms:: IMAGE SI-13 and TIMED/GUVI observations -: art. no. A10308

[1] Thermospheric O/N-2 column density ratios referenced at a N-2 column density of 10(17) cm(-2) are obtained using the IMAGE SI-13 and TIMED/GUVI far-ultraviolet (FUV) dayglow data, AURIC simulation results, and MSIS86 model. Each of the magnetic storms occurring during a 4-day period ( 1 - 4 October 2002) caused significant O/N-2 depletion that was detected by both of the IMAGE SI-13 and GUVI instruments. The depletion extended down to latitudes of 10degrees and - 5degrees in the Northern and Southern Hemispheres, respectively. Simultaneous measurements show an excellent agreement between the SI-13 and GUVI O/N-2 on both global and local scales. The IMAGE SI-13 O/N-2 data provide direct optical evidence that the O/N-2 depletion corotates with the Earth. The GUVI O/N-2 indicate the depletion in both of the hemispheres is not symmetric owing to the seasonal effect and differences in heating and convection induced winds. Both the IMAGE SI-13 and GUVI O/N-2 maps also provide a good opportunity for future modeling efforts.