Solar Cycle Characteristics Examined in Separate Hemispheres

ORAL

Abstract

According to recent research results from solar dynamo models, the north and south hemispheres may evolve separately throughout the solar cycle. Using hemispheric sunspot area from the Royal Greenwich Observatory (RGO), we measured a phase lag between the north and south hemispheres for solar cycles 12-23, which ranged from 0-19 months. We examined the presence of a Gnevyshev gap to determine if the double-peak of any given solar cycle is caused by an averaging of two hemispheres that are out of phase. We confirmed previous findings that show the Gnevyshev gap to be a hemispheric phenomena and is not due to a superposition of sunspot indices from hemispheres slightly out of phase. We then measured the flux crossing the equator by examining Kitt Peak and SOLIS magnetograms for solar cycles 21-23 and found, on average, a surplus of northern hemispheric flux crossing during the mid-declining phase of each solar cycle.

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Authors

  • Doug Petkie

    AFRL/RX, AFRL/RX, Systran Systems Inc, UCSD, Los Alamos National Laboratory, Ohio Northern University, BFS, Germany, Florida State University, Monmouth College, Ohio Wesleyan University, Department of Chemical and Biomolecular Engineering, The University of Akron, Physics Department, John Carroll University, Department of Chemistry, Knight Chemical Laboratories, The University of Akron, Australian National University, Miami University, Oxford, OH, University of Cincinnati, University of Findlay, Naval Research Laboratory, Washington, DC 20375, Cleveland State University, Health Sciences Dept, Cleveland State University, Physics Dept, Cleveland State University, Bucknell University, Wright State University, Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB, Wright State University, Department of Physics, University of Puerto Rico, Department of Mechanical Engineer, Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB and UES, Inc., Department of Environmental Science and Policy, School of Science, Marist College, Poughkeepsie, NY 12601, USA, AFRL/711 HPW, EPA Sustainable Technology Division, University of Akron, Rose-Hulman Institute of Technology, Harvard University, LSU, Ohio University, Wittenberg University, Student