Schematic diagram of the data-driving algorithm. The upper row shows several times from a Ground Truth simulation (GT) and highlights the vertical magnetic field in the layer that will be used for data driving (gray scale). Time flows left to right. The time between each state O in the GT simulation is δt while the time between the extracted data series used for driving (t _O1, t _O2, …) is Δt. Blue arrows represent the intermittent injection of data extracted (or “observed”) from the GT simulation and used in the Driving simulation (Dr). The bottom row shows several times from the resulting Data-Driven simulation from a side-on 3D perspective, which shows vertical velocities in the vertical cut-plane and the magnetic field in the driving plane. Field lines highlight the 3D magnetic structure for each simulation. See text for the full relation between the GT, Driving, and Data-Driven simulations.