| In this work I examine convection during very strong driving during magnetic storms using global MHD simulations of the interaction of the solar wind with the magnetosphere. The MHD simulation code uses solar wind data as a boundary condition, so that it is able to reproduce actual events. Specifically, I examine the variations of the flux tube volume using the simulation of the January 10, 1997 and September 25, 1998 magnetic storms. To perform the numerical integration of the flux tube volume in the simulation, I use SPDX, a supplement to OpenDX, developed by Michael Wiltberger. I find that during substorm---like periods in the simulation---the flux tube volume varies significantly, rising during the growth phase and shrinking during the expansion phase. During main phase of a storm, the flux tube volume remains at evaluated values, though it does vary erratically. I suggest that this is an important feature of global convection during storms, The significance of this work is in that it is the first attempt to study the evolution of the flux tube volume via MHD simulations. |
