Perspective comparison of the GT (left), Δt = 20δt Data-Driven (middle), and Δt = 100δt Data-Driven (right) simulations at four times throughout the simulation (top to bottom, 0, 125, 250, and 375 δt, or times t = 0, 0.38, 0.89, 1.42). The Data-Driven simulations are driven with data extracted from the GT simulation at z = 1.09. The vertical cut shows vertical velocities in the y = 0 plane, and the horizontal cut shows vertical magnetic field in the z = 1.14 plane (the first nondriven cell in the Data-Driven simulations). Seed points of field lines are initiated both below the driving layer (GT simulation only) and above it (all simulations; see text in Appendix F following Equation (F12)). The animation shows the expansion of the spheromak through the driving layer for the GT simulation and the reproduction of those field lines in the two Data-Driven simulations. The low-cadence, Δt = 100δt simulation has notably deformed field lines compared to the other two simulations. The animation runs from time zero to 1.46561 with a real-time duration of 3 s.

(An animation of this figure is available.)

The video/animation of this figure is available in the online journal.