Variation of Global and Local Flows in the Solar Convection Zone during Activity Cycles 24 and 25

Abstract: Convection, differential rotation, and meridional circulation of solar plasma are studied based on helioseismic data covering the period from May 2010 to August 2024, which is significantly prolonged compared to that previously considered. Depth variation in the spatial spectrum of convective motions indicates a superposition of differently scaled flows. The giant-cell-scale component of the velocity field demonstrates a tendency to form meridionally elongated (possibly banana-shaped) structures. The integrated spectral power of the flows is anticorrelated with the solar-activity level in the near-surface layers and positively correlates with it in deeper layers. An extended 22-year cycle of zonal flows (“torsional oscillations” of the Sun) and variations of the meridional flows are traced. A secondary meridional flow observed at the epoch of the maximum of Solar Cycle 24 to be directed equatorward in the subsurface layers is clearly manifest in Cycle 25.