Solar Rossby Wave ``Hills'' Identified as Supergranules

Abstract

We explore the nature of ``hills'' observed on the solar surface that had previously been attributed to Rossby waves. We investigate the solar hills phenomenon by analyzing the output from a synthetic model based solely on the observed solar photospheric convection spectrum. We show that the characteristics of these hills can be explained by the corrugation of the surface produced by the radial flows of the convection. The hills in our simulations are dominated by supergranules, a well-known component of solar convection. Rossby waves have been predicted to exist within the Sun and may play an important role in the dynamics of the solar interior, including the Sun's differential rotation and magnetic dynamo. Our study suggests, however, that the hills observed at the solar limb do not confirm the existence of solar Rossby waves.