Effects of Strong Interplanetary Disturbances on the Dayside Magnetosphere:
Comparison between IMAGE Observations and Global MHD Modeling

J. Berchem 1 (310-206-2849; jberchem@igpp.ucla.edu)
S. A. Fuselier 2
H. U. Frey 3
J. L. Burch 4

1 Institute of Geophysics and Planetary Physics, University of California,
  Los Angeles, CA 90095
2 Lockheed Martin Advanced Technology Center, 3251 Hanover Street,
  Palo Alto, CA 94304
3 Space Science Laboratory, University of California, Berkeley, CA 94720
4 Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238

The ability to model transient responses of the Earth's magnetosphere to
strong interplanetary disturbances is an important step toward
understanding the complex dynamics of geomagnetic storms.
Three-dimensional magnetohydrodynamic (MHD) simulations of the
interaction of the solar wind with the Earth's magnetosphere are used to
study the interaction of interplanetary shocks and strong pressure
pulses with the magnetosphere. The study focuses on identifying and
understanding the large-scale dynamics of the magnetopause boundary and
the intensification of the dayside auroral activity observed on the
arrival of strong interplanetary disturbances. To achieve this goal we
have modeled several events using plasma and magnetic field parameters
measured upstream of the bow shock as input to the simulations and
discuss the simulation results in the context of spacecraft observations
at the magnetospheric boundary and IMAGE auroral observations.