Sunspot Properties and the Solar Dynamo

Norton Aimee, aimee.norton@gmail.com, James Cook/Stanford University, United States

Abstract
Sunspot observations inspired solar dynamo theory and continue to do so. Simply counting them established the sunspot cycle and its period. Latitudinal distributions introduced the tough constraint that the source of sunspots moves equator-ward as the cycle progresses. Observations of Hale's polarity law mandated hemispheric asymmetry. How much more can sunspots tell us about the solar dynamo? I present work using sunspot locations and properties observed by Kitt Peak, MDI and HMI, studied as a function of longitude, hemisphere and field strength. Information about the dynamics of the toroidal bands in the solar interior can be inferred including peak strength, latitudinal width, and the presence of a tipping instability. Non-axisymmetric sunspot properties have largely been ignored except for the establishment of active longitudes. Hemispheric data continue to be averaged resulting in the loss of a wealth of information, as we have, in essence, two dynamos operating somewhat independently at any given time. Including non-axisymmetric and hemispheric properties of sunspots allows for the recovery of more information regarding interior toroidal field dynamics. Caveats are that one must assume a coherent, banded toroidal magnetic field exists at the base of the convection zone with predictable trajectories of the flux as it rises to the surface. Observations of anti-Hale sunspots call into question the wisdom of assuming such a simple toroidal field configuration.