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<front>
<journal-meta>
<journal-id journal-id-type="publisher">EGUsphere</journal-id>
<journal-title-group>
<journal-title>EGUsphere</journal-title>
<abbrev-journal-title abbrev-type="publisher">EGUsphere</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">EGUsphere</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub"></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/egusphere-2026-880</article-id>
<title-group>
<article-title>Contrasting land carbon uptake responses to El Ni&amp;ntilde;o&amp;ndash;Southern Oscillation across North America</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Sun</surname>
<given-names>Wu</given-names>
<ext-link>https://orcid.org/0000-0002-2333-6282</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>Foster</surname>
<given-names>Kelsey</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 contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Shiga</surname>
<given-names>Yoichi</given-names>
<ext-link>https://orcid.org/0000-0001-8569-6841</ext-link>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Merder</surname>
<given-names>Julian</given-names>
<ext-link>https://orcid.org/0000-0002-5958-7016</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>Randazzo</surname>
<given-names>Nina</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
<xref ref-type="aff" rid="aff5">
<sup>5</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Michalak</surname>
<given-names>Anna</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 Global Ecology, Carnegie Institution for Science, Stanford, California, USA</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Department of Earth System Science, Doerr School of Sustainability, Stanford University, Stanford, California, USA</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Independent Researcher, San Francisco, California, USA</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>Global Modeling and Assimilation Office, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA</addr-line>
</aff>
<aff id="aff5">
<label>5</label>
<addr-line>Earth System Science Interdisciplinary Center, University of Maryland, College Park, Maryland, USA</addr-line>
</aff>
<pub-date pub-type="epub">
<day>13</day>
<month>04</month>
<year>2026</year>
</pub-date>
<volume>2026</volume>
<fpage>1</fpage>
<lpage>35</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2026 Wu Sun et al.</copyright-statement>
<copyright-year>2026</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://egusphere.copernicus.org/preprints/2026/egusphere-2026-880/">This article is available from https://egusphere.copernicus.org/preprints/2026/egusphere-2026-880/</self-uri>
<self-uri xlink:href="https://egusphere.copernicus.org/preprints/2026/egusphere-2026-880/egusphere-2026-880.pdf">The full text article is available as a PDF file from https://egusphere.copernicus.org/preprints/2026/egusphere-2026-880/egusphere-2026-880.pdf</self-uri>
<abstract>
<p>El Ni&amp;ntilde;o&amp;ndash;Southern Oscillation (ENSO) drives year-to-year variability in the land carbon sink. While responses of land carbon uptake to ENSO have been documented at aggregated continental scales over North America, these responses arise from ENSO&apos;s climate impacts that vary across subcontinental regions. Disentangling diverse regional responses is crucial for attributing ENSO&apos;s impacts on carbon uptake to climatic drivers. Here, we characterize ENSO-driven carbon&amp;ndash;climate interactions across North America, a data-rich continent with prominent responses to ENSO, by leveraging fine-resolution (1&amp;deg; &amp;times; 1&amp;deg;) top-down estimates of land carbon fluxes derived from tall-tower atmospheric CO&lt;sub&gt;2&lt;/sub&gt; observations and spaceborne chlorophyll fluorescence measurements. We identify regions with distinct ENSO responses in the timing, direction, and magnitude of carbon uptake anomalies. Notably, regions where El Ni&amp;ntilde;o boosts carbon uptake, including the Pacific&amp;ndash;Mountainous West and subtropical lands, are consistent with ENSO-driven shifts in the position of the subtropical jet. We further uncover contrasting patterns in how energy and water limitations mediate ENSO&apos;s impacts on carbon uptake across regions. These findings reveal key regional mechanisms connecting ENSO-driven climate variability with continental-scale carbon uptake responses and highlight the need to reassess tropical carbon&amp;ndash;climate feedbacks in light of compensatory extratropical responses.</p>
</abstract>
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<funding-group>
<award-group id="gs1">
<funding-source>National Aeronautics and Space Administration</funding-source>
<award-id>80NSSC18K0165</award-id>
</award-group>
<award-group id="gs2">
<funding-source>Carnegie Institution for Science</funding-source>
<award-id>Endowment Fund</award-id>
</award-group>
</funding-group>
</article-meta>
</front>
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