The global horizontal circulation of the Sun

Using H-alpha synoptic charts of the distribution of the background magnetic fields in the solar photosphere, the evolution, structure and distribution of the regions of the two magnetic polarities and their boundaries are characterized. A method was found of describing qualitatively the direction of the horizontal streaming of the solar photospheric plasma. A time-variable large-scale vorticity flow was found in the region of the active zone and a nearly zonal flow at higher latitudes. Active regions are exclusively formed in places where the global circulation displays maximum vorticity. Filaments occur in the regions where the value of the velocity gradient is high, perpendicular to the filament axis. The condition for these two manifestations of solar activity to form is the presence of the boundary between the polarities of the background magnetic field. A representative sample of the vectors of both zonal and meridional flows was analyzed. The mean value of the zonal components of the velocity vectors of vorticity flow displays latitude dependence corresponding to the usual dependence of differential rotation. The meridional component displays maximum values of velocity in the active zone and poleward is near zero. (author). 12 figs., 1 tab., 28 refs