SOLAR ACTIVE REGIONS AS DIAGNOSTICS OF SUBSURFACE CONDITIONS

In the past decade a number of observational and theoretical studies h ave appeared that address the problem of how both the physical conditi ons in subsurface layers of the Sun and the nature of the magnetic flu x tubes of active regions are reflected in the structure and behavior of these regions at the surface, This review discusses work in this ar ea. Many characteristics of plages and sunspot groups are shown to be related to the conditions encountered by the region flux tube as it ri ses through the convective zone of the Sun to the surface. Size distri butions, rotation and meridional flow rates and their covariances, and characteristics of growth and decay are among the factors that have b een shown to depend on the nature of the source magnetic flux tube and the physical effects, such as the Coriolis force and magnetic tension , that act deep in the convection zone.