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<front>
<journal-meta>
<journal-id journal-id-type="publisher">CP</journal-id>
<journal-title-group>
<journal-title>Climate of the Past</journal-title>
<abbrev-journal-title abbrev-type="publisher">CP</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">Clim. Past</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1814-9332</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/cp-9-1015-2013</article-id>
<title-group>
<article-title>Large spatial variations in coastal &lt;sup&gt;14&lt;/sup&gt;C reservoir age &amp;ndash; a case study from the Baltic Sea</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Lougheed</surname>
<given-names>B. C.</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>Filipsson</surname>
<given-names>H. L.</given-names>
<ext-link>https://orcid.org/0000-0001-7200-8608</ext-link>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Snowball</surname>
<given-names>I.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Department of Geology, Lund University, Sölvegatan 12, 22362 Lund, Sweden</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Department of Earth Sciences &amp;ndash; Geophysics, Uppsala University, Villavägen 16, 75236 Uppsala, Sweden</addr-line>
</aff>
<pub-date pub-type="epub">
<day>07</day>
<month>05</month>
<year>2013</year>
</pub-date>
<volume>9</volume>
<issue>3</issue>
<fpage>1015</fpage>
<lpage>1028</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2013 B. C. Lougheed et al.</copyright-statement>
<copyright-year>2013</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://cp.copernicus.org/articles/9/1015/2013/cp-9-1015-2013.html">This article is available from https://cp.copernicus.org/articles/9/1015/2013/cp-9-1015-2013.html</self-uri>
<self-uri xlink:href="https://cp.copernicus.org/articles/9/1015/2013/cp-9-1015-2013.pdf">The full text article is available as a PDF file from https://cp.copernicus.org/articles/9/1015/2013/cp-9-1015-2013.pdf</self-uri>
<abstract>
<p>Coastal locations are highly influenced by input from freshwater river
runoff, including sources of terrestrial carbon, which can be expected to
modify the &lt;sup&gt;14&lt;/sup&gt;C reservoir age, or &lt;i&gt;R (t)&lt;/i&gt;, associated with marine water.
In this Baltic Sea case study, pre-bomb museum collection mollusc shells of
known calendar age, from 30 locations across a strategic salinity transect of
the Baltic Sea, were analysed for &lt;sup&gt;14&lt;/sup&gt;C, &amp;delta;&lt;sup&gt;13&lt;/sup&gt;C and &amp;delta;&lt;sup&gt;18&lt;/sup&gt;O. 
&lt;i&gt;R (t)&lt;/i&gt; was calculated for all 30 locations. Seven locations, of
which six are within close proximity of the coast, were found to have
relatively higher &lt;i&gt;R (t)&lt;/i&gt; values, indicative of hard-water effects. Whenever
possible, the &lt;i&gt;Macoma&lt;/i&gt; genus of mollusc was selected from the museum
collections, in order to exclude species specific reservoir age effects as
much as possible. When the &lt;i&gt;Macoma&lt;/i&gt; samples are exclusively
considered, and samples from hard-water locations excluded, a statistically
significant correlation between &lt;i&gt;Macoma&lt;/i&gt; &lt;i&gt;R (t)&lt;/i&gt; and average salinity
is found, indicating a two end-member linear mixing model between
&lt;sup&gt;14&lt;/sup&gt;C&lt;sub&gt;marine&lt;/sub&gt; and &lt;sup&gt;14&lt;/sup&gt;C&lt;sub&gt;runoff&lt;/sub&gt;. A map of Baltic Sea
&lt;i&gt;Macoma&lt;/i&gt; aragonite &lt;i&gt;R (t)&lt;/i&gt; for the late 19th and early 20th centuries
is produced. Such a map can provide an estimate for contemporary Baltic Sea
&lt;i&gt;Macoma&lt;/i&gt; &lt;i&gt;R (t)&lt;/i&gt;, although one must exercise caution when applying such
estimates back in time or to &lt;sup&gt;14&lt;/sup&gt;C dates obtained from different sample
material. A statistically significant correlation is found between &amp;delta;&lt;sup&gt;18&lt;/sup&gt;O&lt;sub&gt;aragonite&lt;/sub&gt; 
and &lt;i&gt;Macoma&lt;/i&gt; &lt;i&gt;R (t)&lt;/i&gt;, suggesting that
&amp;delta;&lt;sup&gt;18&lt;/sup&gt;O&lt;sub&gt;aragonite&lt;/sub&gt; can be used to estimate &lt;i&gt;Macoma&lt;/i&gt;
palaeo-&lt;i&gt;R (t)&lt;/i&gt;, due to the &amp;delta;&lt;sup&gt;18&lt;/sup&gt;O&lt;sub&gt;aragonite&lt;/sub&gt; signal being
dominated by the salinity gradient of the Baltic Sea. A slightly increased
correlation can be expected when &amp;delta;&lt;sup&gt;18&lt;/sup&gt;O&lt;sub&gt;aragonite&lt;/sub&gt; is
corrected for temperature fractionation effects. The results of this Baltic
Sea case study, which show that &lt;i&gt;R (t)&lt;/i&gt; is affected by hydrographic conditions
and local carbon inputs, have important consequences for other coastal and
estuarine locations, where &lt;i&gt;R (t)&lt;/i&gt; is also likely to significantly vary on
spatial and temporal bases.</p>
</abstract>
<counts><page-count count="14"/></counts>
</article-meta>
</front>
<body/>
<back>
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