Effect of Geospace Model Resolution on Predictions of Ground Magnetic Perturbations

Abstract:

Numerical prediction of space weather can be done using numerical geospace models capable of wide range of spatial resolutions. Using a Lyon-Fedder-Mobarry (LFM) global magnetohydrodynamic magnetosphere-ionosphere simulation of the Whole Heliosphere Interval (WHI), we examine the impact of model resolution on predictions of various space weather parameters, with the present study focusing on ground magnetic field response. To accomplish this, we have developed a Biot-Savart integrator, which calculates the spatial magnetic field from its source electric current. We validate the LFM Biot-Savart module using simple geospace current distributions with known analytic solutions. Then, by synthesizing ground magnetometer responses to WHI conditions, we compute metrics that quantify the impact of geospace model resolution on simulated geological hazards that directly influence, among other things, geomagnetically induced currents (GICs) in electric power grids.