Fig. 2. An idealized model for the ocean of an icy moon.
(A) Diagram of an icy moon, the ice shell of which is thin at the poles and thick at the equator. The nonuniform ice shell induces a temperature gradient at the top of the ocean. We use a cosine temperature profile, as shown in (B), to represent this top temperature forcing in our numerical simulations. Here, ΔT is the pole-to-equator temperature difference, and Ts is the top temperature. (C) Setup of our numerical simulations. We use a cuboid to represent the ocean; in Cartesian coordinates, the x, y, and z directions point eastward, northward, and upward, respectively. The green arrows in (A) and (C) show the Coriolis parameters at different locations.