Observational aspects of the formation of near-surface toroidal magnetic fields on the Sun are considered. Based on the analysis of magnetic field observations in the period 2010–2024, diagrams of the distribution of horizontal magnetic fields and magnetic bipoles of ephemeral regions in the solar cycle are obtained. The obtained diagrams are close to the concept of an extended cycle of solar activity. The formation of surface azimuthal magnetic fields is modeled based on the evolution of U-shaped magnetic bipoles of active regions. Taking into account near-equatorial bipoles with a magnetic field propagating through the solar equator in the modeling made it possible to achieve good agreement with the duration of the azimuthal field polarity at low latitudes.
A. G. Tlatov (Wed,) studied this question.