Coronal magnetic field, wind velocity, and rotation rate at three illustrative moments of the solar cycle (from left to right: solar minimum, maximum, and decay phase, corresponding to instants t = 0, 3.8, and 4 yr in Fig. 3 of Pinto et al. 2011). The left halves of the panels show meridional slices of the wind speed (sonic Mach number from 0 in solid blue to 2 in solid yellow, and with the yellow–blue boundary representing the sonic surface), and the right halves show slices of the rotation rate of the solar corona (from 0 in black to 14° /day in light orange). Top and bottom rows correspond to cases with a standard differential rotation and to solid-body rotation at the lower boundary (the lower boundary of the corona is coloured with the same Ω colour scale as the slices on the right side of the images). Blue lines represent magnetic field lines. The frame of reference is inertial (not co-moving with the Sun), hence Ω is positive everywhere.