Sunspot cycle variations of ensemble-averaged active regions

Abstract

We examine published sunspot and calcium plage areas for 1620 solar active regions between 1974 and 1985. With these data we study the properties of ensemble-averaged active regions. The average sunspot area per region, the average plage to sunspot area ratio, and the average plage intensity of regions all vary significantly with the sunspot cycle and in correlation with one another. The average plage area per region varies significantly but is uncorrelated with the sunspot cycle and with the other quantities. While the plage and sunspot areas and the plage intensities of individual active regions observed over a two-year period are strongly correlated, the relationship among these quantities appears to change over an 11-yr period. These results suggest the existence of some energetic connection between active region sunspot areas and plage intensities. Further, if energy balance between sunspot luminosity deficits and facular luminosity excesses holds, then standard models relating these quantities to sunspot and plage areas will have to be modified. Overall energy balance can neither be established nor ruled out.