An investigation of the magnetosphere-ionosphere response to real and idealized co-rotating interaction region events through global magnetohydrodynamic simulations

This study investigates the role of interplanetary magnetic field (IMF) B_z fluctuations periodicity in the transfer of solar wind mass and energy to the magnetosphere during the co-rotating interaction region/high-speed stream event of 10 November 2003 through global modelling simulations using the space weather modelling framework. To do so, we used both solar wind observations and a variety of idealized inputs as upstream boundary conditions, describing different solar wind configurations for which relative contribution of the peak-to-noise ratio in the input B_z power spectrum to the periodicity transfer is examined. Fast Fourier transforms of both input to and the response of the magnetosphere reveal that the transfer of IMF B_z periodicity to the magnetosphere is unaltered by other solar wind parameters, although the size of the peak-to-noise ratio of the input signal is the controlling factor that determines this transfer. The global magnetosphere simulation suggests that a threshold amount of power (peak-to-noise ratio) of approximately 10 in the input signal is needed for the magnetosphere to react to the periodicity in the input B_z , while for the cross-polar cap potential, the threshold amount is significantly smaller.