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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-2026-3583</article-id>
<title-group>
<article-title>CoMIAR v1.0: a hybrid system for multi-species adjoint inversion of atmospheric emissions with online adaptive regularization</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Mai</surname>
<given-names>Zelin</given-names>
<ext-link>https://orcid.org/0009-0006-6807-4948</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>Shen</surname>
<given-names>Huizhong</given-names>
<ext-link>https://orcid.org/0000-0003-1335-8477</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>Liu</surname>
<given-names>Qiming</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>Zhang</surname>
<given-names>Ruixin</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>Guo</surname>
<given-names>Peng</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>Shen</surname>
<given-names>Han</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>Luan</surname>
<given-names>Tiancheng</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>Xu</surname>
<given-names>Junpeng</given-names>
<ext-link>https://orcid.org/0009-0005-0436-7437</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>He</surname>
<given-names>Jinling</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>Zheng</surname>
<given-names>Zhiyu</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>Chen</surname>
<given-names>Yilin</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>Zhao</surname>
<given-names>Shunliu</given-names>
<ext-link>https://orcid.org/0000-0003-0738-1048</ext-link>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Hakami</surname>
<given-names>Amir</given-names>
<ext-link>https://orcid.org/0000-0003-3122-9548</ext-link>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>State Key Laboratory of Soil Pollution Control and Safety, Shenzhen Key Laboratory of  Precision Measurement and Early Warning Technology for Urban Environmental Health   Risks, School of Environmental Science and Engineering, Southern University of Science  and Technology, Shenzhen 518055, China</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Guangdong Provincial Observation and Research Station for Coastal Atmosphere and  Climate of the Greater Bay Area, School of Environmental Science and Engineering,   Southern University of Science and Technology, Shenzhen 518055, China</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>School of Urban Planning and Design, Peking University, Shenzhen Graduate School,  Shenzhen 100871, China</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>Department of Civil and Environmental Engineering, Carleton University, Ottawa, Ontario  K1S5B6, Canada</addr-line>
</aff>
<pub-date pub-type="epub">
<day>27</day>
<month>07</month>
<year>2026</year>
</pub-date>
<volume>2026</volume>
<fpage>1</fpage>
<lpage>25</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2026 Zelin Mai 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-2026-3583/">This article is available from https://egusphere.copernicus.org/preprints/2026/egusphere-2026-3583/</self-uri>
<self-uri xlink:href="https://egusphere.copernicus.org/preprints/2026/egusphere-2026-3583/egusphere-2026-3583.pdf">The full text article is available as a PDF file from https://egusphere.copernicus.org/preprints/2026/egusphere-2026-3583/egusphere-2026-3583.pdf</self-uri>
<abstract>
<p>Accurate estimates of anthropogenic emissions are fundamental to air quality and climate assessment. Satellite-based top-down inversion offers an independent constraint on bottom-up emission inventories, but two key limitations remain. First, dynamically constrained 4D-Var optimization often relies on fixed regularization parameters, which can destabilize convergence during iteration. Second, most inversions treat chemical species separately, even though atmospheric species are chemically coupled. Here, we develop CoMIAR v1.0 (Coupled Multi- species Inversion with Adaptive Regularization), a hybrid system implemented with CMAQ- Adjoint to address these limitations. CoMIAR combines mass-balance initialization with 4D- Var optimization, extends the adjoint formulation to a fully coupled multi-species control system, and incorporates an online Iterative-Adaptive Regularization (IAR) strategy that updates the species-specific regularization factor at each iteration using the L-curve criterion, thereby avoiding fixed empirical tuning. In observing system simulation experiments over China, IAR suppressed the convergence oscillations observed under fixed-parameter schemes. In the single-species SO&lt;sub&gt;2&lt;/sub&gt; regularization experiment, IAR reduced emission NRMSE by 50.5 % from the 4D-Var starting point and achieved the lowest final error among the tested schemes. Joint multi-species inversion further exploited sulfate-nitrate-ammonium thermodynamic coupling to separate emission biases that single-species inversions could not resolve. CoMIAR remained robust under spatially heterogeneous prior errors. Together, CoMIAR provides a stable and chemically consistent approach for emission inversion in complex atmospheric systems.</p>
</abstract>
<counts><page-count count="25"/></counts>
<funding-group>
<award-group id="gs1">
<funding-source>National Key Research and Development Program of China</funding-source>
<award-id>2023YFE0112901</award-id>
</award-group>
<award-group id="gs2">
<funding-source>National Natural Science Foundation of China</funding-source>
<award-id>42475108</award-id>
<award-id>42192512</award-id>
<award-id>42330709</award-id>
<award-id>42571087</award-id>
</award-group>
<award-group id="gs3">
<funding-source>HORIZON EUROPE Framework Programme</funding-source>
<award-id>101137905</award-id>
</award-group>
<award-group id="gs4">
<funding-source>Shenzhen Science and Technology Innovation Program</funding-source>
<award-id>KQTD20240729102048052</award-id>
<award-id>JCYJ20241202152804007</award-id>
</award-group>
</funding-group>
</article-meta>
</front>
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<back>
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</article>