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Description
We investigate the large-scale longitudinal and hemispheric organization of solar magnetic activity across multiple solar cycles, including Cycles 23, 24, and the ongoing Cycle 25. Using synoptic magnetic maps and flare catalogues, we examine the relationship between active longitudes, the spatial distribution of magnetically complex active regions, and the preferred longitudes of the most energetic solar flares.
Our analysis reveals that solar activity exhibits systematic hemispheric asymmetries that evolve with the solar cycle phase. Activity tends to dominate one hemisphere during the rising phase, often shifts around solar maximum, and may reorganize again during the declining phase. In addition, strong magnetic flux concentrations and major flares are not randomly distributed in longitude but cluster along persistent active longitudes that can remain stable for several Carrington rotations before undergoing abrupt longitudinal relocations of approximately 160°–180°. The evolution of these active longitudes displays quasi-periodic behavior on timescales of roughly 0.5–2 years, detectable in both magnetic and flare data.