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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-2026-2662</article-id>
<title-group>
<article-title>Atmospheric methane growth rates, 2018-2024, driven mainly by emission changes but atmospheric photochemistry is important</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Feng</surname>
<given-names>Liang</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>Palmer</surname>
<given-names>Paul I.</given-names>
<ext-link>https://orcid.org/0000-0002-1487-0969</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>Wang</surname>
<given-names>Haolin</given-names>
<ext-link>https://orcid.org/0000-0001-8783-3782</ext-link>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Parker</surname>
<given-names>Robert</given-names>
<ext-link>https://orcid.org/0000-0002-0801-0831</ext-link>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Boesch</surname>
<given-names>Hartmut</given-names>
<ext-link>https://orcid.org/0000-0003-3944-9879</ext-link>
</name>
<xref ref-type="aff" rid="aff5">
<sup>5</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Biraud</surname>
<given-names>Sébastien C.</given-names>
<ext-link>https://orcid.org/0000-0001-7697-933X</ext-link>
</name>
<xref ref-type="aff" rid="aff6">
<sup>6</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Chmura</surname>
<given-names>Łukasz</given-names>
<ext-link>https://orcid.org/0000-0003-4950-4827</ext-link>
</name>
<xref ref-type="aff" rid="aff7">
<sup>7</sup>
</xref>
<xref ref-type="aff" rid="aff8">
<sup>8</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Gloor</surname>
<given-names>Emanuel</given-names>
</name>
<xref ref-type="aff" rid="aff9">
<sup>9</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Haszpra</surname>
<given-names>László</given-names>
<ext-link>https://orcid.org/0000-0002-7747-6475</ext-link>
</name>
<xref ref-type="aff" rid="aff10">
<sup>10</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Kozlova</surname>
<given-names>Elena</given-names>
</name>
<xref ref-type="aff" rid="aff11">
<sup>11</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Nisbet</surname>
<given-names>Euan G.</given-names>
</name>
<xref ref-type="aff" rid="aff12">
<sup>12</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Noe</surname>
<given-names>Steffen M.</given-names>
<ext-link>https://orcid.org/0000-0003-1514-1140</ext-link>
</name>
<xref ref-type="aff" rid="aff13">
<sup>13</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Röckmann</surname>
<given-names>Thomas</given-names>
<ext-link>https://orcid.org/0000-0002-6688-8968</ext-link>
</name>
<xref ref-type="aff" rid="aff14">
<sup>14</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Ferreira de Souza</surname>
<given-names>Rodrigo Augusto</given-names>
</name>
<xref ref-type="aff" rid="aff15">
<sup>15</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Steinbacher</surname>
<given-names>Martin</given-names>
<ext-link>https://orcid.org/0000-0002-7195-8115</ext-link>
</name>
<xref ref-type="aff" rid="aff16">
<sup>16</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>National Centre for Earth Observation, University of Edinburgh, Edinburgh, UK</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>National Centre for Earth Observation, Space Park Leicester, University of Leicester, Leicester, UK</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>Earth Observation Science, School of Physics and Astronomy, University of Leicester, Leicester, UK</addr-line>
</aff>
<aff id="aff5">
<label>5</label>
<addr-line>Institute of Environmental Physics, University of Bremen, Bremen, Germany</addr-line>
</aff>
<aff id="aff6">
<label>6</label>
<addr-line>Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA</addr-line>
</aff>
<aff id="aff7">
<label>7</label>
<addr-line>AGH University of Krakow, Faculty of Physics and Applied Computer Science, Krakow, Poland</addr-line>
</aff>
<aff id="aff8">
<label>8</label>
<addr-line>Institute of Meteorology and Water Management, National Research Institute, Warsaw, Poland</addr-line>
</aff>
<aff id="aff9">
<label>9</label>
<addr-line>School of Geography, University of Leeds, Leeds, UK</addr-line>
</aff>
<aff id="aff10">
<label>10</label>
<addr-line>Institute for Marine and Atmospheric research Utrecht (IMAU), Utrecht University, Utrecht, the Netherlands</addr-line>
</aff>
<aff id="aff11">
<label>11</label>
<addr-line>College of Life and Environmental Sciences, University of Exeter, Exeter, UK</addr-line>
</aff>
<aff id="aff12">
<label>12</label>
<addr-line>Department of Earth Sciences, Royal Holloway, University of London, London, UK</addr-line>
</aff>
<aff id="aff13">
<label>13</label>
<addr-line>Institute of Forestry and Engineering, Estonian University of Life Sciences, Tartu, Estonia</addr-line>
</aff>
<aff id="aff14">
<label>14</label>
<addr-line>Institute for Nuclear Research (ATOMKI), Debrecen, Hungary</addr-line>
</aff>
<aff id="aff15">
<label>15</label>
<addr-line>School of Technology, University of the State of Amazonas (UEA), Manaus, AM, Brazil</addr-line>
</aff>
<aff id="aff16">
<label>16</label>
<addr-line>Swiss Federal Laboratories for Materials Science and Technology (EMPA), Dübendorf, Switzerland</addr-line>
</aff>
<pub-date pub-type="epub">
<day>29</day>
<month>05</month>
<year>2026</year>
</pub-date>
<volume>2026</volume>
<fpage>1</fpage>
<lpage>29</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2026 Liang Feng 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-2026-2662/">This article is available from https://egusphere.copernicus.org/preprints/2026/egusphere-2026-2662/</self-uri>
<self-uri xlink:href="https://egusphere.copernicus.org/preprints/2026/egusphere-2026-2662/egusphere-2026-2662.pdf">The full text article is available as a PDF file from https://egusphere.copernicus.org/preprints/2026/egusphere-2026-2662/egusphere-2026-2662.pdf</self-uri>
<abstract>
<p>Global atmospheric methane growth rate has increased dramatically since 2007, peaking in 2021, yet the relative roles of emissions and atmospheric oxidation remain uncertain. Accurate attribution is essential for climate mitigation because emissions-driven and chemistry-driven changes imply fundamentally different policy responses. Here we investigate global methane production and loss from 2018 to 2024 using an ensemble Kalman filter coupled to the GEOS‑Chem model. We employ two methane inversion configurations: assuming climatological monthly OH distributions or jointly optimizing zonal mean OH with methane. The joint inversion reveals substantial interannual variability in OH, including an ~18% decline in 2020 followed by a recovery in subsequent years. Accounting for this variability reduces the inferred 2019&amp;ndash;2020 emission increase by ~63% (14&amp;plusmn;6 Tg/yr versus 37&amp;plusmn;5.5 Tg/yr with fixed OH), demonstrating that changes in OH strongly influences source attribution. The total increased methane loss, 2024 minus 2019, is about 31&amp;plusmn;6 Tg/yr, including a temperature‑driven increase of the OH+methane reaction rate that represents about 40% of the total sink increase. Most of the sink variations originate from the tropics, where the largest shifts in emission occur.&amp;nbsp; Despite year-to-year variations, emissions remain the primary driver of changes in the methane growth rate change, except in 2020. &amp;nbsp;Both inversions identify significant emission reductions over tropical South America in 2023&amp;ndash;2024, likely linked to regional drought. Broadly, our results underscore the necessity of jointly estimating methane sources and sinks to interpret recent atmospheric methane trends.&amp;nbsp;</p>
</abstract>
<counts><page-count count="29"/></counts>
<funding-group>
<award-group id="gs1">
<funding-source>Natural Environment Research Council</funding-source>
<award-id>NE/R016518/1</award-id>
<award-id>NE/N018079/1</award-id>
</award-group>
</funding-group>
</article-meta>
</front>
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</article>