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<front>
<journal-meta>
<journal-id journal-id-type="publisher">ESDD</journal-id>
<journal-title-group>
<journal-title>Earth System Dynamics Discussions</journal-title>
<abbrev-journal-title abbrev-type="publisher">ESDD</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">Earth Syst. Dynam. Discuss.</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">2190-4995</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/esdd-5-327-2014</article-id>
<title-group>
<article-title>Statistical significance of rising and oscillatory trends in global ocean and land temperature in the past 160 years</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Østvand</surname>
<given-names>L.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Rypdal</surname>
<given-names>K.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Rypdal</surname>
<given-names>M.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Department of Physics and Technology, UiT The Arctic University of Norway, Tromsø, Norway</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Department of Mathematics and Statistics, UiT The Arctic University of Norway, Tromsø, Norway</addr-line>
</aff>
<pub-date pub-type="epub">
<day>20</day>
<month>03</month>
<year>2014</year>
</pub-date>
<volume>5</volume>
<issue>1</issue>
<fpage>327</fpage>
<lpage>362</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2014 L. Østvand et al.</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://esd.copernicus.org/preprints/5/327/2014/esdd-5-327-2014.html">This article is available from https://esd.copernicus.org/preprints/5/327/2014/esdd-5-327-2014.html</self-uri>
<self-uri xlink:href="https://esd.copernicus.org/preprints/5/327/2014/esdd-5-327-2014.pdf">The full text article is available as a PDF file from https://esd.copernicus.org/preprints/5/327/2014/esdd-5-327-2014.pdf</self-uri>
<abstract>
<p>Various interpretations of the notion of a trend in the context of
  global warming are discussed, contrasting the difference between
  viewing a trend as the deterministic response to an external forcing
  and viewing it as a slow variation which can be separated from the
  background spectral continuum of long-range persistent climate
  noise. The emphasis in this paper is on the latter notion, and
  a general scheme is presented for testing a multi-parameter trend
  model against a null hypothesis which models the observed climate
  record as an autocorrelated noise. The scheme is employed to the
  instrumental global sea-surface temperature record and the global
  land temperature record. A trend model comprising a linear plus an
  oscillatory trend with period of approximately 70 yr, and
  the statistical significance of the trends, are tested against three
  different null models: first-order autoregressive process,
  fractional Gaussian noise, and fractional Brownian motion. The
  parameters of the null models are estimated from the instrumental
  record, but are also checked to be consistent with a Northern
  Hemisphere temperature reconstruction prior to 1750 for which an
  anthropogenic trend is negligible. The linear trend in the period
  1850–2010 AD is significant in all cases, but the oscillatory trend
  is insignificant for ocean data and barely significant for land
  data. However, by using the significance of the linear trend to
  constrain the null hypothesis, the oscillatory trend in the land
  record appears to be statistically significant. The results suggest
  that the global land record may be better suited for detection of
  the global warming signal than the ocean record.</p>
</abstract>
<counts><page-count count="36"/></counts>
</article-meta>
</front>
<body/>
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