Time evolution of R_ramp shown in panel a. Time evolution of (b) |B_y/B_x|, (d) gas pressure gradient in the y-direction, (f) Lorentz force in the y-direction, (h) gravity force, (j) total force in the y-direction before the localized heating is imposed are shown on the left column. Panels in the right column show the time evolution of these parameters after the localized heating is on, correspondingly.