The effect of IMF fluctuations on the subsolar magnetopause position

Abstract:

This study examines the effect of interplanetary magnetic field (IMF) fluctuations on the subsolar magnetopause position. Studies have been conducted on this position with steady state IMF conditions, even including a flip from northward IMF to southward IMF. Under southward IMF conditions, the subsolar magnetopause moves inward. This is generally referred to as magnetopause erosion. Solar wind conditions are not usually constant for very long, especially during such conditions as are present in high-speeds streams, which typically have large fluctuations in the interplanetary magnetic field (IMF). These IMF fluctuations can occur on a range of times scales and amplitudes, resulting in a series of northward and southward IMF intervals imposed on the magnetosphere. We simulate the effect of such IMF variations on the magnetopause position using a global MHD model. We will present the dependence of the subsolar magnetopause position on the frequency and amplitude of the IMF oscillations.