Density from a 2D, boundary-driven advection problem: the alfven.vtk image is used to set time-dependent boundary values at the top edge, advected into the domain by a constant advection speed, v = −e_y. We show the solution at t = 1.15 on a [0,1] × [0, 1.5] domain. The four-level AMR hierarchy is purely geometrically controlled in this example, forcing the central band of the image to appear sharpest.