Spatial–temporal evolution of photospheric weak-field shifts in solar cycles 21–24

Context. Weak magnetic field elements make a dominant contribution to the total on solar surface. Even so, little is known of their long-term occurrence. Aims. We study spatial–temporal evolution weak-field shift and skewness distribution photospheric values during cycles 21−24 in order clarify role relation weak overall evolution. Methods. used Wilcox Solar Observatory (WSO) Synoptic Optical Long-term Investigations Sun Vector SpectroMagnetograph synoptic maps calculate shifts for each latitude bin map, thereby constructed time–latitude butterfly diagram shifts. also calculated diagrams all only. Results. The (full-field) depict similar cycle that large-scale surface field. has systematic non-zero large already at (and after) emergence active region, even highest resolution. find evidence coalescence opposite-polarity fields surge This clearly more effective supergranulation scale. However, dependence spatial resolution was not found unipolar regions around poles. Conclusions. Our results give preference weakest toward prevailing polarity since an stronger opposite polarities produce process reduced or turned off These observations improve understanding only development elements, but dynamics large, processes below