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<front>
<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-2016-29</article-id>
<title-group>
<article-title>Trend analysis by a piecewise linear regression model applied to surface air temperatures in Southeastern Spain (1973&amp;ndash;2014)</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Campra</surname>
<given-names>Pablo</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>Morales</surname>
<given-names>Maria</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Engineering School D2.36, University of Almeria, Almeria 04120, Spain</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Mathematics Department. University of Almeria, Almeria 04120, Spain</addr-line>
</aff>
<funding-group>
<award-group id="gs1">
<funding-source>Ministerio de Economía y Competitividad</funding-source>
<award-id>CGL2013-46873-R</award-id>
</award-group>
</funding-group>
<pub-date pub-type="epub">
<day>30</day>
<month>05</month>
<year>2016</year>
</pub-date>
<volume>2016</volume>
<fpage>1</fpage>
<lpage>25</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2016 Pablo Campra</copyright-statement>
<copyright-year>2016</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://npg.copernicus.org/preprints/npg-2016-29/">This article is available from https://npg.copernicus.org/preprints/npg-2016-29/</self-uri>
<self-uri xlink:href="https://npg.copernicus.org/preprints/npg-2016-29/npg-2016-29.pdf">The full text article is available as a PDF file from https://npg.copernicus.org/preprints/npg-2016-29/npg-2016-29.pdf</self-uri>
<abstract>
<p>The magnitude of the trends of environmental and climatic changes is mostly derived from the slopes of the linear trends using ordinary least-square fitting. An alternative flexible fitting model, piecewise regression, has been applied here to surface air temperature records in southeastern Spain for the recent warming period (1973&amp;ndash;2014) to gain accuracy in the description of the inner structure of change, dividing the time series into linear segments with different slopes. Breakpoint years, with confidence intervals (CIs), were estimated and separated periods of significant trend change were determined. First, simple linear trends for mean, maximum and minimum surface air temperatures and diurnal temperature range (DTR) from the four longest and most reliable historic records in SE Spain were estimated. All series in the region showed intense linear warming signs during the period 1973&amp;ndash;2014. However, updated warming trends were lower than those previously cited for the region and Spain from the 1970s onwards. Piecewise regression model allowed us to detect breakpoints in the series, and the absence of significant trends in the most recent period of the segmented fits for two stations. In general, piecewise regression model showed better fit than simple linear regression model, and thus, showed a better description of temperature variability.</p>
</abstract>
<counts><page-count count="25"/></counts>
</article-meta>
</front>
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