<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE article PUBLIC "-//NLM//DTD Journal Publishing DTD v3.0 20080202//EN" "https://jats.nlm.nih.gov/nlm-dtd/publishing/3.0/journalpublishing3.dtd">
<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" article-type="research-article" dtd-version="3.0" xml:lang="en">
<front>
<journal-meta>
<journal-id journal-id-type="publisher">ANGEO</journal-id>
<journal-title-group>
<journal-title>Annales Geophysicae</journal-title>
<abbrev-journal-title abbrev-type="publisher">ANGEO</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">Ann. Geophys.</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1432-0576</issn>
<publisher><publisher-name>Copernicus Publications</publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/angeo-32-1035-2014</article-id>
<title-group>
<article-title>Difference between even- and odd-numbered cycles in the predictability of solar activity and prediction of the amplitude of cycle 25</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Yoshida</surname>
<given-names>A.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Shizuoka University, 836, Ohya, Suruga-ku, Shizuoka, 422-8529, Japan</addr-line>
</aff>
<pub-date pub-type="epub">
<day>25</day>
<month>08</month>
<year>2014</year>
</pub-date>
<volume>32</volume>
<issue>8</issue>
<fpage>1035</fpage>
<lpage>1042</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2014 A. Yoshida</copyright-statement>
<copyright-year>2014</copyright-year>
<license license-type="open-access">
<license-p>This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit <ext-link ext-link-type="uri"  xlink:href="https://creativecommons.org/licenses/by/3.0/">https://creativecommons.org/licenses/by/3.0/</ext-link></license-p>
</license>
</permissions>
<self-uri xlink:href="https://angeo.copernicus.org/articles/32/1035/2014/angeo-32-1035-2014.html">This article is available from https://angeo.copernicus.org/articles/32/1035/2014/angeo-32-1035-2014.html</self-uri>
<self-uri xlink:href="https://angeo.copernicus.org/articles/32/1035/2014/angeo-32-1035-2014.pdf">The full text article is available as a PDF file from https://angeo.copernicus.org/articles/32/1035/2014/angeo-32-1035-2014.pdf</self-uri>
<abstract>
<p>It was shown previously that the sunspot number (SSN) at a point 3 years
before the minimum is well correlated with the maximum SSN of the succeeding
cycle, and a better correlation is obtained when the maximum SSN is replaced
by the average SSN over a cycle for which the average SSN is calculated by
dividing cycles at a point 3 years before the minimum (Yoshida and
Yamagishi, 2010; Yoshida and Sayre, 2012). Following these findings, we
demonstrate in this paper that the correlation between the SSN 3 years
before the minimum and the amplitude of the coming cycle differs
significantly between even-numbered and odd-numbered cycles: the correlation
is much better for even-numbered cycles. Further, it is shown that the
amplitude of even-numbered cycles is strongly correlated with that of the
succeeding odd-numbered cycles, while the correlation between amplitudes of
odd-numbered cycles and those of succeeding even-numbered cycles is very
poor. Using the excellent correlations, we estimate the maximum SSN of the
current cycle 24 at 81.3 and predict the maximum SSN of cycle 25 to be
115.4 ± 11.9. It is of note, however, that a peak of the SSN has been
observed in February 2012 and the peak value 66.9 is considerably smaller
than the estimated maximum SSN of cycle 24. We conjecture that the second
higher peak of the SSN may appear.</p>
</abstract>
<counts><page-count count="8"/></counts>
</article-meta>
</front>
<body/>
<back>
<ref-list>
<title>References</title>
<ref id="ref1">
<label>1</label><mixed-citation publication-type="other" xlink:type="simple">Belucz, B. and Dikpati, M.: Role of asymmetric meridional circulation in producing north-south asymmetry in a solar cycle dynamo model, Astrophys. J., 779, &lt;a href=&quot;http://dx.doi.org/10.1088/0004-637X/779/1/4&quot;&gt;https://doi.org/10.1088/0004-637X/779/1/4&lt;/a&gt;, 2013.</mixed-citation>
</ref>
<ref id="ref2">
<label>2</label><mixed-citation publication-type="other" xlink:type="simple">Cameron, R. and Schussler, M.: Solar cycle prediction using precursors and flux transport models, Astrophys. J., 659, 801–811, 2007a.</mixed-citation>
</ref>
<ref id="ref3">
<label>3</label><mixed-citation publication-type="other" xlink:type="simple">Cameron, R. and Schussler, M.: Are solar cycle predictable?, Astron. Nachr, 328, 1087–1091, 2007b.</mixed-citation>
</ref>
<ref id="ref4">
<label>4</label><mixed-citation publication-type="other" xlink:type="simple">Cameron, R. and Schussler, M.: A robust correlation between growth rate and amplitude of solar cycles: Consequences for prediction methods, Astrophys. J., 685, 1291–1296, 2008.</mixed-citation>
</ref>
<ref id="ref5">
<label>5</label><mixed-citation publication-type="other" xlink:type="simple">Charbonneau, P. and Dikpati, M.: Stochastic fluctuations in a Babcock-Leighton model of the solar cycle, Astrophys. J., 543, 1027–1043, 2000.</mixed-citation>
</ref>
<ref id="ref6">
<label>6</label><mixed-citation publication-type="other" xlink:type="simple">Dikpati, M. and Gilman, P. A.: Simulating and predicting solar cycles using a flux-transport dynamo, Astrophys. J., 649, 498–514, 2006.</mixed-citation>
</ref>
<ref id="ref7">
<label>7</label><mixed-citation publication-type="other" xlink:type="simple">Dikpati, M., de Toma, G., and Gilman, P. A.: Predicting the strength of solar cycle 24 using a flux-transport dynamo-based tool, Geophys. Res. Lett., 23, L05102, &lt;a href=&quot;http://dx.doi.org/10.1029/2005GL025221&quot;&gt;https://doi.org/10.1029/2005GL025221&lt;/a&gt;, 2006.</mixed-citation>
</ref>
<ref id="ref8">
<label>8</label><mixed-citation publication-type="other" xlink:type="simple">Dikpati, M., Gilman, P. A., de Toma, G., and Ghosh, S. S.: Simulating solar cycles in northern and southern hemisphere by assimilatingmagnetic data into a calibrated flux-transport dynamo, Solar Physics, 245, 1–17, 2007.</mixed-citation>
</ref>
<ref id="ref9">
<label>9</label><mixed-citation publication-type="other" xlink:type="simple">Dikpati, M., Gilman, P. A., and de Toma, G.: The Waldmeier effect: An artifact of the definition of Wolf sunspot number?, Astrophys. J., 673, L99–L101, 2008.</mixed-citation>
</ref>
<ref id="ref10">
<label>10</label><mixed-citation publication-type="other" xlink:type="simple">Hathaway, D. H. and Wilson, R. M.: Geomagnetic activity indicates large amplitude for sunspot cycle 24, Geophys. Res. Lett., 33, L18101, &lt;a href=&quot;http://dx.doi.org/10.1029/2006GL027053&quot;&gt;https://doi.org/10.1029/2006GL027053&lt;/a&gt;, 2006.</mixed-citation>
</ref>
<ref id="ref11">
<label>11</label><mixed-citation publication-type="other" xlink:type="simple">Hathaway, D. H., Nandy, D., Wilson, R. M., and Reichmann, E. J.: Evidence that a deep meridional flow sets the sunspot cycle period, Astrophys. J., 589, 665–670, 2003.</mixed-citation>
</ref>
<ref id="ref12">
<label>12</label><mixed-citation publication-type="other" xlink:type="simple">Hathaway, D. H., Nandy, D., Wilson, R. M., and Reichmann, E. J.: Erratum: &quot;Evidence that a deep meridional flow sets the sunspot cycle period, Astrophys. J., 602, p. 543, 2004.</mixed-citation>
</ref>
<ref id="ref13">
<label>13</label><mixed-citation publication-type="other" xlink:type="simple">Kane, R. P.: A preliminary estimate of the size of the coming solar cycle 24, based on Ohl&apos;s precursor method, Solar Phys., 243, 205–217, 2007.</mixed-citation>
</ref>
<ref id="ref14">
<label>14</label><mixed-citation publication-type="other" xlink:type="simple">Ohl, A. I.: Forecast of sunspot maximum number of cycle 20, Solice Donie, 9, 84–85, 1966.</mixed-citation>
</ref>
<ref id="ref15">
<label>15</label><mixed-citation publication-type="other" xlink:type="simple">Pesnell, W. D.: Prediction of solar cycle 24, Solar Phys., 252, 209–220, 2008.</mixed-citation>
</ref>
<ref id="ref16">
<label>16</label><mixed-citation publication-type="other" xlink:type="simple">Schatten, K. H.: Fair space weather for solar cycle 24, Geophys. Res. Lett., 32, L21106, &lt;a href=&quot;http://dx.doi.org/10.1029/2005GL024363&quot;&gt;https://doi.org/10.1029/2005GL024363&lt;/a&gt;, 2005.</mixed-citation>
</ref>
<ref id="ref17">
<label>17</label><mixed-citation publication-type="other" xlink:type="simple">Svalgaard, L., Cliver, E. W., and Kamide, Y.: Sunspot cycle 24: Smallest cycle in 100 years?, Geophys. Res. Lett., 32, L01104, &lt;a href=&quot;http://dx.doi.org/10.1029/2004GL021664&quot;&gt;https://doi.org/10.1029/2004GL021664&lt;/a&gt;, 2005.</mixed-citation>
</ref>
<ref id="ref18">
<label>18</label><mixed-citation publication-type="other" xlink:type="simple">Thompson, R. J.: The rise of solar cycle number 22, Solar Phys., 117, 279–289, 1988.</mixed-citation>
</ref>
<ref id="ref19">
<label>19</label><mixed-citation publication-type="other" xlink:type="simple">Waldmeier, M.: Neue Eigenschaften der Sonnenfleckenkurve, Astronomische Mitteilungen Zurich, 14, 105–130, 1935.</mixed-citation>
</ref>
<ref id="ref20">
<label>20</label><mixed-citation publication-type="other" xlink:type="simple">Yeates, A. P., Nandy, D., and Mackay, D. H.: Exploring the physical basis of solar cycle predictions: Flux transport dynamics and presence of memory in advection- versus diffusion-dominated solar convection zones, Astrophys. J., 673, 544–556, 2008.</mixed-citation>
</ref>
<ref id="ref21">
<label>21</label><mixed-citation publication-type="other" xlink:type="simple">Yoshida, A. and Sayre, R.: Tendency of discreteness of the solar amplitude and intercycle relatedness, Advances in Astronomy, 2012, 519852, &lt;a href=&quot;http://dx.doi.org/10.1155/2012/519852&quot;&gt;https://doi.org/10.1155/2012/519852&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref22">
<label>22</label><mixed-citation publication-type="other" xlink:type="simple">Yoshida, A. and Yamagishi, H.: Predicting amplitude of solar cycle 24 based on a new precursor method, Ann. Geophys., 28, 417–425, &lt;a href=&quot;http://dx.doi.org/10.5194/angeo-28-417-2010&quot;&gt;https://doi.org/10.5194/angeo-28-417-2010&lt;/a&gt;, 2010.</mixed-citation>
</ref>
</ref-list>
</back>
</article>