HR: 1330h
AN: SA13A-08    [Abstracts]
TI: Auroral Undulations During Magnetic Storms: TIMED/GUVI Observations
AU: * Zhang, Y
EM: yongliang.zhang@jhuapl.edu
AF: The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 United States
AU: Paxton, L J
EM: larry.paxton@jhuapl.edu
AF: The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 United States
AU: Morrison, D
EM: danny.morrison@jhuapl.edu
AF: The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 United States
AU: Lui, T
EM: tony.lui@jhuapl.edu
AF: The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 United States
AU: Kil, H
EM: hyosub.kil@jhuapl.edu
AF: The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 United States
AU: Wolven, B
EM: brian.wolven@jhuapl.edu
AF: The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 United States
AU: Meng, C I
EM: ching.meng@jhuapl.edu
AF: The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 United States
AB: Giant undulations on the equatorward edge of the diffuse aurora have been identified in TIMED/GUVI auroral images in the far ultraviolet wavelengths. Some new features have been observed: (1) The GUVI 121.6nm auroral images provide direct optical evidence that the undulations occur in the proton aurora, (2) Undulations are not limited to the dusk sector, they can occur in all local time sectors, (3) Both large ionospheric ion drift velocity (1000 m/s and above) and strong velocity shear (> 0.1 1/s) appear to be a necessary condition for the undulation to occur, (4) While almost all of the undulation events are observed during magnetic storms (Dst < -60 nT), one exceptional case shows undulation in the dayside associated with a positive Dst (30 nT), a large solar wind speed and a high solar wind dynamic pressure. The undulations can be explained by the K-H instability.
DE: 2407 Auroral ionosphere (2704)
DE: 2463 Plasma convection
DE: 2704 Auroral phenomena (2407)
DE: 2788 Storms and substorms
SC: SPA-Aeronomy [SA]
MN: 2005 Joint Assembly