  A Rossby-Haurwitz (RH) wave is an excitation mode of a fluid on a rotating
spherical surface, which propagates westward in the rotating frame of
reference. Motivated by the recent realization of the shell-shaped
Bose-Einstein condensate in microgravity, we investigate the RH wave in a
superfluid rotating on a spherical-surface geometry. We employ the point-vortex
model and the three-dimensional Gross-Pitaevskii equation, and numerically
demonstrate that RH waves can be observed in the system of a superfluid with
quantized vortices.
