The Gleissberg cycle by a nonlinear alpha Lambda dynamo

This paper suggests a numerical model of the Gleissberg cycle based on a sp herical shell dynamo. The formulation of the problem includes a description both of the rotation law and of the hydromagnetic dynamo. The suggested mo del allows the Gleissberg cycle to be interpreted as resulting from the mag netic feedback on the angular momentum fluxes which maintain the rotation l aw in the shell. The period of the long-term variations is determined by re laxation properties of the shell. Hence, it is directly associated with the time taken to re-establish the differential rotation after the magnetic pe rturbations of the angular momentum transport.