On theories of rotating convection zones

It is shown that the time rate of change brought about by turbulent convective motions in the angular momentum of a thin spherical shell is such as to increase the angular velocity of the lower part of the solar convection zone (SCZ) and to decrease the angular velocity of the upper part. Arguments are presented in favor of the following very tentative model of rotation in the SCZ: (1) the lower region is in weaker differential rotation than the surface and not constrained by the Taylor-Proudman theorem, and (2) the observed solar differential rotation at the surface is generated as the SCZ relaxes from the state in the lower part to the state at the surface. In the upper and lower layers of the SCZ, angular-momentum conservation between the turbulent motions and viscous stresses leads to an angular velocity increasing upward.