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<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-2025-5852</article-id>
<title-group>
<article-title>The Spatial and Temporal Distribution Patterns of XCH₄ in Iran: New Insights from TROPOMI Observations</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Rahimi</surname>
<given-names>Ali</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>Farajzadeh</surname>
<given-names>Manuchehr</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>Ghavidel</surname>
<given-names>Yousef</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>Karoff</surname>
<given-names>Christoffer</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Department of Physical Geography, Tarbiat Modares University, Tehran, 14155-4838, Iran</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Department of Geoscience, Aarhus University, Aarhus, 8000 Aarhus C, Denmark</addr-line>
</aff>
<pub-date pub-type="epub">
<day>11</day>
<month>12</month>
<year>2025</year>
</pub-date>
<volume>2025</volume>
<fpage>1</fpage>
<lpage>20</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2025 Ali Rahimi 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://egusphere.copernicus.org/preprints/2025/egusphere-2025-5852/">This article is available from https://egusphere.copernicus.org/preprints/2025/egusphere-2025-5852/</self-uri>
<self-uri xlink:href="https://egusphere.copernicus.org/preprints/2025/egusphere-2025-5852/egusphere-2025-5852.pdf">The full text article is available as a PDF file from https://egusphere.copernicus.org/preprints/2025/egusphere-2025-5852/egusphere-2025-5852.pdf</self-uri>
<abstract>
<p>The unprecedented increase in methane concentration, as the second most important greenhouse gas after carbon dioxide, poses a serious challenge to climate change mitigation policies, while accurate and comprehensive monitoring remains insufficient in many countries, including Iran. This study investigates the spatial and temporal patterns of column-averaged methane in Iran using satellite-based observations from Tropospheric Monitoring Instrument on the Sentinel-5P satellite during 2019&amp;ndash;2024 and compares them with data from the Emissions Database for Global Atmospheric Research database. On average, XCH₄ concentrations across Iran increased from 1872.6 &amp;plusmn; 11.9 ppb in 2019 to 1918.6 &amp;plusmn; 11.2 ppb in 2024, representing a +46.1 &amp;plusmn; 16.4 ppb rise over six years. All uncertainty estimates represent standard deviations, with a mean value of 12.3 ppb. Statistical and spatial analyses, including Global Moran&amp;rsquo;s I (0.914&amp;ndash;0.982, p &amp;lt; 0.01), Local Moran&amp;rsquo;s I, and the Getis-Ord Gi* hotspot analysis, confirmed that methane concentrations in Iran exhibit a significant clustering pattern. Hotspots were mainly observed in Class 1: Northern Agro-Hotspots (Gilan, Mazandaran, and Golestan), Class 2: Central Urban-Dense Hotspots, and Class 3: Southern Industrial-Fossil Hotspots, whereas Class 4: Low-Emission Provinces and Class 5: Very-Low-Emission Provinces exhibited lower concentrations with sparse hotspots, located mostly in western and eastern Iran. The highest seasonal averages were recorded in summer (1914.3 &amp;plusmn; 13.1 ppb) and autumn (1910.5 &amp;plusmn; 13.5 ppb). Comparison with EDGAR data indicates that several major emission sources are underestimated, and spatial overlaps with the observed hotspots did not exceed 5 % in any month. Satellite observations reveal discrepancies in hotspot locations and emission magnitudes, emphasizing that relying solely on modeled inventories may misrepresent methane emissions.</p>
</abstract>
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