Abstract
The distribution of magnetic fields of positive and negative polarities over the Sun’s surface has been studied. Synoptic maps of the photospheric magnetic field (NSO Kitt Peak, 1978–2016) were used as the initial data. The latitude–time diagram for weak magnetic fields (B ≤ 5 G) clearly shows tilted bands, which indicate the alternate dominance of magnetic fields with positive or negative polarity drifting towards the Sun’s poles. The analysis of the latitude–time diagram using the method of empirical orthogonal functions (EOFs) made it possible to reveal a cyclic variation of the polarity of magnetic field fluxes with a period of 1–3 years, which indicates a possible relation to quasi-biennial oscillations. Similar values of the periods were obtained by latitudinal averaging of the latitude–time diagram.
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ACKNOWLEDGMENTS
The NSO/Kitt Peak data used here are produced cooperatively by NSF/NOAO, NASA/GSFC, and NOAA/SEL (ftp://nispdata.nso.edu/kpvt/synoptic/mag/). Data acquired by SOLIS instruments were operated by NISP/NSO/ AURA/NSF (https://magmap.nso.edu/solis/archive.html). The authors express their gratitude to the reviewer for careful reading of the article and helpful remarks.
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Translated by M. Chubarova
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Vernova, E.S., Tyasto, M.I. & Baranov, D.G. Cyclic Variations of the Polarity of the Photospheric Magnetic Field. Geomagn. Aeron. 62, 945–951 (2022). https://doi.org/10.1134/S0016793222070192
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DOI: https://doi.org/10.1134/S0016793222070192