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<journal-meta>
<journal-id journal-id-type="publisher">NPGD</journal-id>
<journal-title-group>
<journal-title>Nonlinear Processes in Geophysics Discussions</journal-title>
<abbrev-journal-title abbrev-type="publisher">NPGD</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">Nonlin. Processes Geophys. Discuss.</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">2198-5634</issn>
<publisher><publisher-name></publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/npg-2019-12</article-id>
<title-group>
<article-title>On the nonlinear and Solar-forced nature of the Chandler wobble in the Earth&apos;s pole motion</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Sonechkin</surname>
<given-names>Dmitry M.</given-names>
<ext-link>https://orcid.org/0000-0003-3771-3824</ext-link>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Shirshov Oceanology Institute, RAS, Moscow, Russia</addr-line>
</aff>
<pub-date pub-type="epub">
<day>26</day>
<month>04</month>
<year>2019</year>
</pub-date>
<volume>2019</volume>
<fpage>1</fpage>
<lpage>7</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2019 Dmitry M. Sonechkin</copyright-statement>
<copyright-year>2019</copyright-year>
<license license-type="open-access">
<license-p>This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this licence, visit <ext-link ext-link-type="uri"  xlink:href="https://creativecommons.org/licenses/by/4.0/">https://creativecommons.org/licenses/by/4.0/</ext-link></license-p>
</license>
</permissions>
<self-uri xlink:href="https://npg.copernicus.org/preprints/npg-2019-12/">This article is available from https://npg.copernicus.org/preprints/npg-2019-12/</self-uri>
<self-uri xlink:href="https://npg.copernicus.org/preprints/npg-2019-12/npg-2019-12.pdf">The full text article is available as a PDF file from https://npg.copernicus.org/preprints/npg-2019-12/npg-2019-12.pdf</self-uri>
<abstract>
<p>&lt;p&gt;About 250 years ago L. Euler has derived a system of three quadratic-nonlinear differential equations to depict the rotation of the Earth as a rigid body. Neglecting a small distinction between the equatorial inertia moments, he reduced this system to much simpler linear one, and concluded that the Earth&apos;s pole must experience a harmonic oscillation of the 304-day period. Astronomers could not find this oscillation, but instead, S.C Chandler has found two powerful wobbles with the 12- and ~&amp;thinsp;14-month periods in reality. Adhering to the Euler&apos;s linearization, astronomers can not explain the nature of the later wobble up to now. I indicate that the neglect by the above small distinction (“a small parameter” of the Euler&apos;s primary nonlinear equations) is not admissible because the effect of this parameter is singular. Analysing the primary equations by an asymptotic technique, I demonstrate that the Chandler wobble tones are formed from combinational harmonics of the Euler&apos;s 304-day oscillation, long-term Luni-Solar tides as well as the 22-year cycle of the heliomagnetic activity. Correlating simultaneous variations of the wobble and a solar activity index, I corroborate that the Chandler wobble is really affected by the Sun.&lt;/p&gt;</p>
</abstract>
<counts><page-count count="7"/></counts>
</article-meta>
</front>
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