HR: 0800h
AN: SA21A-0295 [Abstracts]
TI: Analysis of the Octuber 3-7 2000 GEM Storm with the WINDMI Model
AU: * Horton, W
EM: horton@physics.utexas.edu
AF: Institute for Fusion Studies, The University of Texas at Austin, 1 University Station, C1500, Austin,
TX 78712
United States
AU: Spencer, E A
EM: espencer@ece.utexas.edu
AF: Institute for Fusion Studies, The University of Texas at Austin, 1 University Station, C1500, Austin,
TX 78712
United States
AU: Doxas, I
EM: isidoros.doxas@colorado.edu
AF: Center for Integrated Plasma Studies, University of Colorado, Boulder, CO 80309
United States
AU: Kozyra, J U
EM: jukozyra@umich.edu
AF: Department of Oceanic and Atmospheric Sciences, University of Michigan, Ann Arbor, MI 48109
United States
AB:
he 8 dimensional physics model WINDMI is used to analyze the October 3-7,
2000 geomagnetic storm using solar wind input data from the ACE satellite. This
period was chosen because it contains an extended interval of well-defined and
quasi-periodic auroral activations called sawtooth oscillations, a phenomena
whose relationship to substorm processes and to upstream solar wind drivers is
still under debate. The question of whether multiple sawtooth
oscillations are triggered by periodic upstream solar wind features or by internal
magnetospheric processes is addressed. The model predicts
both the occurrence of 8 auroral activations identified as sawtooth
events during the 24 hour period on the 4th of October, in agreement with the
measured AL index, and also an earlier multiple sawtooth interval on the 3rd of
October, in agreement with the measured AL index. These intervals occur
during steady but moderate solar wind IMF Bz values and the periodicity of the
sawtooth events was not directly related to any periodic features in the upstream
solar wind. The model also predicts the geomagnetic Dst} index through the main
and recovery phase of the storm.
DE: 2721 Field-aligned currents and current systems (2409)
DE: 2788 Magnetic storms and substorms (7954)
DE: 2790 Substorms
DE: 7954 Magnetic storms (2788)
SC: SPA-Aeronomy [SA]
MN: Fall Meeting 2005