HR: 0800h
AN: SM51A-0340    [Abstracts]
TI: Meso-Scale Velocity Structure in the High Latitude F Region
AU: * Johnson, E S
EM: ejohnson@utdallas.edu
AF: The University of Texas at Dallas, 2601 N. Floyd Rd, MS/FO22, Richardson, TX 75080 United States
AU: Heelis, R A
EM: heelis@utdallas.edu
AF: The University of Texas at Dallas, 2601 N. Floyd Rd, MS/FO22, Richardson, TX 75080 United States
AB: At high latitudes in the F region the bulk ion flow is driven predominantly by electric fields originating in the magnetosphere and magnetosheath. During times of southward IMF a large-scale 2-cell convection pattern usually prevails with characteristic spatial scales of 1000 km (10 degrees of latitude). In addition to this large-scale convection feature there exist smaller scale velocity structures with scale sizes ranging from 1001s of km to 101s of meters. At intermediate scales between 10 km and 1000 km the ion velocity structure can have a significant impact on the ion temperature and perhaps the neutral gas velocity. Here we report on a study of the characteristics of ion velocity structure and the corresponding neutral behavior in this scale size range. We examine the characteristics of structure and its influence on neutral particles in the auroral zone and polar cap in the winter and summer hemispheres during times of southward IMF. We also consider relationships between the structure of the ions and the ion bulk flow to determine occurrences probabilities of certain features within the data.
DE: 2431 Ionosphere/magnetosphere interactions (2736)
DE: 2475 Polar cap ionosphere
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting