An analysis of heliospheric magnetic field flux based on sunspot number from 1749 to today and prediction for the coming solar minimum

Authors

  • Molly L. Goelzer,

    1. Physics Department, Space Science Center, University of New Hampshire, Durham, New Hampshire, USA
    2. Also in Department of Chemical Engineering, University of New Hampshire, Durham, New Hampshire, USA
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  • Charles W. Smith,

    Corresponding author
    1. Physics Department, Space Science Center, University of New Hampshire, Durham, New Hampshire, USA
    • Corresponding author: C. W. Smith, Physics Department and Space Science Center, University of New Hampshire, Room 207 Morse Hall, 39 College Rd., Durham, NH 03824, USA. (Charles.Smith@unh.edu)

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  • Nathan A. Schwadron,

    1. Physics Department, Space Science Center, University of New Hampshire, Durham, New Hampshire, USA
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  • K. G. McCracken

    1. Institute of Physical Science and Technology, University of Maryland, College Park, Maryland, USA
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Abstract

[1] It is now well established that many bulk properties of the solar wind rise and fall with the solar cycle, and the heliospheric magnetic field (HMF) intensity is no exception. The HMF intensity is seen to be maximum around the time of solar maximum, lowest during solar minimum, and lower still during the recent protracted solar minimum 2006–2009. One explanation of this behavior can be found in the theory of Schwadron et al. (2010) that argues magnetic flux is injected into interplanetary space by coronal mass ejection eruptions and removed by reconnection in the low solar atmosphere. This produces an HMF intensity that is correlated with sunspot number, and the rapid injection of flux followed by the slow removal by reconnection results in a hysteresis effect that is readily evident in the observations. Here for the first time we apply this theory to the sunspot record going back to 1749 and compare favorably our predictions to the results derived from10Be observations. We also make a prediction for the coming solar minimum based on results from the Dalton Minimum.

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