Alternative Magnetic Structure
Oscillating poloidal field from convection zone is pulled into tachocline.
From this, differential rotation induces a dynamo in the tachocline with B of order 100 kGauss!
This strong field will induce prolateness in the tachocline, which is observed.
Problem #1: Requires exact frequency of oscillating poloidal field.
Problem #2: Neither of these magnetic field arrangments confine convection at the poles.