HR: 0830h
AN: SM11C-1170    [PDF]
TI: Simultaneous Polar Aurorae and Convection Patterns in Both Hemispheres
AU: * Cumnock, J A
EM: cumnock@utdallas.edu
AF: University of Texas at Dallas, Center for Space Sciences PO Box 830688 MS/FO22, Richardson, TX 75083-0688 United States
AU: * Cumnock, J A
EM: cumnock@utdallas.edu
AF: Alfven Laboratory, Royal Institute of Technology, Stockholm, SE-10044 Sweden
AU: Blomberg, L G
EM: lars.blomberg@alfvenlab.kth.se
AF: Alfven Laboratory, Royal Institute of Technology, Stockholm, SE-10044 Sweden
AB: Transpolar arcs are often observed during northward IMF with dawnside (duskside) formation of the TPA and duskward (dawnward) motion occurring when By changes from negative to positive (positive to negative). Whereas simultaneous theta aurorae have been observed in both hemispheres utilizing satellite UV imagers, it is unknown how often theta aurorae occur in both hemispheres and the influence of the IMF. We investigate occurrence of TPAs in both hemispheres. Polar UVI provides images in the northern hemisphere while DMSP provides ionospheric plasma flow and precipitating particle data in both hemispheres. Concurrent solar wind plasma and interplanetary magnetic field measurements are provided by the ACE satellite. Observations indicate that TPAs and theta aurorae depend not only on the orientation of IMF Bz, but on the direction of IMF Bx and By as well. Utilizing the satellite data as inputs, the Royal Institute of Technology model provides the high-latitude ionospheric electrostatic potential patterns in both hemispheres calculated at different times during the evolution of the theta aurora resulting from a variety of field-aligned current configurations associated with the changing global aurora.
DE: 2407 Auroral ionosphere (2704)
DE: 2411 Electric fields (2712)
DE: 2463 Plasma convection
DE: 2475 Polar cap ionosphere
DE: 2736 Magnetosphere/ionosphere interactions
SC: SPA - Magnetospheric Physics [SM]
MN: 2003 Fall Meeting