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<front>
<journal-meta>
<journal-id journal-id-type="publisher">ESSDD</journal-id>
<journal-title-group>
<journal-title>Earth System Science Data Discussions</journal-title>
<abbrev-journal-title abbrev-type="publisher">ESSDD</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">Earth Syst. Sci. Data Discuss.</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1866-3591</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/essd-2025-364</article-id>
<title-group>
<article-title>A database of databases for Common Era paleoclimate applications</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Evans</surname>
<given-names>Michael N.</given-names>
<ext-link>https://orcid.org/0000-0003-3727-6898</ext-link>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Lücke</surname>
<given-names>Lucie J.</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>Fan</surname>
<given-names>Kevin J.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Zhu</surname>
<given-names>Feng</given-names>
<ext-link>https://orcid.org/0000-0002-9969-2953</ext-link>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Department of Geology and Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, USA</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>School of Geosciences, University of Edinburgh, Edinburgh, UK</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Computer Science and Geology, University of Maryland, College Park, MD, USA</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>NSF National Center for Atmospheric Research, Boulder, CO, USA</addr-line>
</aff>
<pub-date pub-type="epub">
<day>01</day>
<month>07</month>
<year>2025</year>
</pub-date>
<volume>2025</volume>
<fpage>1</fpage>
<lpage>25</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2025 Michael N. Evans et al.</copyright-statement>
<copyright-year>2025</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://essd.copernicus.org/preprints/essd-2025-364/">This article is available from https://essd.copernicus.org/preprints/essd-2025-364/</self-uri>
<self-uri xlink:href="https://essd.copernicus.org/preprints/essd-2025-364/essd-2025-364.pdf">The full text article is available as a PDF file from https://essd.copernicus.org/preprints/essd-2025-364/essd-2025-364.pdf</self-uri>
<abstract>
<p>We present a database of curated databases (DoD2k version 1) developed for Common Era (1&amp;ndash;2000 A.D.) paleoclimate research. The DoD2k leverages existing community efforts, many of which arise from the PAGES (Past Global Changes) 2k working group, and the codebase developed by the paleoclimate data informatics communities over the past decade. Using a common, compact set of terms for metadata and data management, we merge five existing curated databases. These individual curated databases represent a range of approaches, from single archive-single observation to multiarchive-multiobservation collections, and span a total of 14 archives, 49 data types, and 4613 records within the Common Era. We then use a multistage algorithm to remove duplicates, checking against a common set of metadata and comparison metrics. We illustrate the value of the DoD2k with two applications. In the first, we extract the moisture and temperature subset of records and perform an empirical orthogonal function (EOF) analysis on the resulting multi-archive, multi-observation dataset. In the second, we show that calcite speleothem oxygen isotopic composition is consistent with proxy system simulations. DoD2k may also be useful for paleoclimatic detection and attribution analysis using proxy system modeling, data assimilation, and deep learning for the development and testing of improved proxy system models.</p>
</abstract>
<counts><page-count count="25"/></counts>
<funding-group>
<award-group id="gs1">
<funding-source>Wolfson Foundation</funding-source>
<award-id>RSWVF\R1\221018</award-id>
</award-group>
<award-group id="gs2">
<funding-source>Directorate for Geosciences</funding-source>
<award-id>AGS2303530</award-id>
</award-group>
</funding-group>
</article-meta>
</front>
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