Study of Global-Scale Surface Flows of the Sun in Past 10 Solar Cycles

Abstract:

Surface flows have played essential roles in predicting solar cycles and connecting the signatures of the solar dynamo. In order to provide the surface flows, such as meridional flows, differential rotation, and zonal flows, in 10 solar cycles, as input for the dynamo and solar cycle modeling, we track the flows from Halpha images as a proxy for magnetic features using Local Correlation Tracking (LCT) tool. In this work, we present the preliminary result of the derived flow maps using the Halpha data from Kanzelho ̈he Solar Observatory (KSO). The correlation between the chromospheric flows and surface flows makes deriving the surface flows on a wide range of time-scales achievable. We aim to provide the long-term observational constraints of surface flows, including hemispheric and latitudinal dependence.