Based on particle-in-cell (PIC) simulation results of collisionless driven reconnection in a steady state, an effective resistivity model is developed for a magnetohydrodynamic (MHD) simulation in order to bridge the huge gap between macro- and microphysics of magnetic reconnection. The PIC simulation reveals that the reconnection electric field sustained by microscopic physics is found to evolve so as to balance the flux inflow rate, which is determined by global dynamics in a macroscopic system. This effective resistivity model is applied to MHD phenomena controlled by magnetic reconnection in the Earth's magnetosphere. Although this model does not include any adjustable parameters related to kinetic dissipation processes, some global phenomena such as the onset of magnetic substorm, dipolarization and propagation of flux rope, detailed processes of which are longstanding questions, are reproduced well in the MHD simulation and are consistent with the observations.
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