Numerical simulations of the magnetic field distribution in a solar complex of activity

Powerful solar complexes of activity are supposed to result from the excitation of Rossby vortices within a thin layer beneath the convection zone. Numerical simulations demonstrate that Rossby vortices generate large-scale arc-like magnetic structures. It is shown that the most powerful complex of activity observed in June-July 1982 was likely to be a result of the excitation of a Rossby anticyclone rather than a cyclone.