SIMULATION OF GEOMAGNETIC STORMS DURING THE PASSAGE OF MAGNETIC CLOUDS

The response of the Earth's magnetosphere to the passage of interplanetary magnetic clouds is simulated using a three-dimensional magnetohydrodynamic (MHD) model. The input solar wind condition is give? by the magnetic field, particle density, and plasma flow calculated from a model magnetic cloud. The cross-polar potential (Phi(p)), Joule heating and electron energy precipitation into the polar cap are calculated. Synthetic magnetic indices D-st* and AE* are defined to serve as surrogates for the usual D-st and AE indices, respectively. We demonstrate that Phi(p)(2) provides a good predictor of the energy deposition into the ionosphere during storm conditions and that D-st* and AE* behave qualitatively similarly to D-st and AE.