Dikpati, et. al., derive magnetic toroids from surface magnetograms by employing a novel optimization method based on Trust Region Reflective algorithm. Toroids obtained are combinations of Fourier modes (amplitudes and phases) with low longitudinal wavenumbers.

Evidence of the existence of hydrodynamic and MHD Rossby waves in the Sun is accumulating rapidly.

The key elements of the Babcock-Leighton dynamos are the generation of poloidal field through decay and dispersal of tilted bipolar active regions and the generation of toroidal field through the observed differential rotation.