Paul Bushby ,   DAMTP  University of Cambridge

Cyclic variations are observed in the solar differential rotation profile.
The 11 year periodicity of these (so-called) torsional oscillations is consistent with the idea that they are magnetically driven.
It is possible to investigate this process by considering a simple mean-field model
for the solar dynamo which incorporates the non-linear feedback of the Lorentz force upon the angular velocity.
It is shown that it is possible to reproduce a solar-like pattern of torsional oscillations,
even in models where the dynamo action is strongly modulated.