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<ArticleSet>
<Article>
<Journal>
				<PublisherName>Kurdistan University of Medical Sciences</PublisherName>
				<JournalTitle>Journal of Advances in Environmental Health Research</JournalTitle>
				<Issn>2676-3478</Issn>
				<Volume>14</Volume>
				<Issue>1</Issue>
				<PubDate PubStatus="epublish">
					<Year>2026</Year>
					<Month>03</Month>
					<Day>29</Day>
				</PubDate>
			</Journal>
<ArticleTitle>Air Quality Assessment Before and During COVID-19 Using Sentinel-5P Satellite and Ground Station Data in Ahvaz, Bushehr, and Bandar Abbas</ArticleTitle>
<VernacularTitle></VernacularTitle>
			<FirstPage>42</FirstPage>
			<LastPage>48</LastPage>
			<ELocationID EIdType="pii">242850</ELocationID>
			
<ELocationID EIdType="doi">10.34172/jaehr.1437</ELocationID>
			
			<Language>EN</Language>
<AuthorList>
<Author>
					<FirstName>Mokhtar</FirstName>
					<LastName>Kavoosi</LastName>
<Affiliation>Department of Environment, Faculty of Natural Resources, Khorramshahr University of Marine Sciences and Technology, Khorramshahr, Iran</Affiliation>
<Identifier Source="ORCID">0009-0009-3788-0009</Identifier>

</Author>
<Author>
					<FirstName>Hossein Mohammed</FirstName>
					<LastName>Asgari</LastName>
<Affiliation>Department of Environment, Khorramshahr University of Marine Sciences and Technology, Khorramshahr, Iran</Affiliation>
<Identifier Source="ORCID">0000-0001-7673-0753</Identifier>

</Author>
</AuthorList>
				<PublicationType>Journal Article</PublicationType>
			<History>
				<PubDate PubStatus="received">
					<Year>2025</Year>
					<Month>07</Month>
					<Day>08</Day>
				</PubDate>
			</History>
		<Abstract>&lt;strong&gt;&lt;span&gt;Introduction:&lt;/span&gt;&lt;/strong&gt;&lt;span&gt; The current study investigated temporal variations in six air pollutants: PM&lt;sub&gt;2.5&lt;/sub&gt;, PM&lt;sub&gt;10&lt;/sub&gt;, SO&lt;sub&gt;2&lt;/sub&gt;, NO&lt;sub&gt;3&lt;/sub&gt;, O&lt;sub&gt;3&lt;/sub&gt;, CO in the cities of Ahvaz, Bandar Abbas, and Bushehr during 2018–2022, with a focus on the pre- and during-COVID-19 periods.&lt;/span&gt;
&lt;strong&gt;&lt;span&gt;Methods: &lt;/span&gt;&lt;/strong&gt;&lt;span&gt;SO&lt;sub&gt;2&lt;/sub&gt;, NO&lt;sub&gt;2&lt;/sub&gt;, CO, and O&lt;sub&gt;3&lt;/sub&gt; data were obtained from the TROPOMI sensor onboard Sentinel-5P (7 × 7 km resolution) using Google Earth Engine (GEE). PM&lt;sub&gt;2.5 &lt;/sub&gt;and PM&lt;sub&gt;10&lt;/sub&gt; concentrations were estimated from Aerosol Optical Depth (AOD) data derived from MODIS MCD19A2 (1 km resolution) using a regression model calibrated with ground-based monitoring data. Records with &gt; 30% cloud cover or missing values were excluded, and monthly and annual means were calculated. Satellite observations were bias-corrected via linear regression against ground-based data and downscaled using bilinear interpolation. Inter-city comparisons were conducted using independent t-tests, while pre- vs. during-pandemic differences were assessed using paired t-tests.&lt;/span&gt;
&lt;strong&gt;&lt;span&gt;Results: &lt;/span&gt;&lt;/strong&gt;&lt;span&gt;Ahvaz recorded the highest mean concentrations of PM&lt;sub&gt;2.5&lt;/sub&gt;, PM&lt;sub&gt;10&lt;/sub&gt;, SO&lt;sub&gt;2&lt;/sub&gt;, and CO. In most cases, pollutant concentrations were higher before the COVID-19 pandemic, particularly for PM&lt;sub&gt;2.5&lt;/sub&gt; and PM&lt;sub&gt;10&lt;/sub&gt; in Ahvaz and Bushehr (&lt;em&gt;P&lt;/em&gt; &lt; 0.05). Correlations between satellite-derived and ground-based measurements of PM&lt;sub&gt;2.5 &lt;/sub&gt;and PM&lt;sub&gt;10&lt;/sub&gt; were strong and statistically significant in Ahvaz and Bushehr, but weak or non-significant for SO&lt;sub&gt;2&lt;/sub&gt;, NO&lt;sub&gt;2&lt;/sub&gt;, and O&lt;sub&gt;3&lt;/sub&gt;.&lt;/span&gt;
&lt;strong&gt;&lt;span&gt;Conclusion: &lt;/span&gt;&lt;/strong&gt;&lt;span&gt;The integration of satellite observations with ground-based monitoring systems provides a reliable and cost-efficient approach to air quality assessment. Reductions in certain pollutants, especially particulate matter, were associated with decreased industrial activity and transportation during the pandemic. &lt;/span&gt;</Abstract>
		<ObjectList>
			<Object Type="keyword">
			<Param Name="value">Air Quality</Param>
			</Object>
			<Object Type="keyword">
			<Param Name="value">Sentinel-5 satellite</Param>
			</Object>
			<Object Type="keyword">
			<Param Name="value">Air Pollutants</Param>
			</Object>
			<Object Type="keyword">
			<Param Name="value">COVID-19</Param>
			</Object>
		</ObjectList>
<ArchiveCopySource DocType="pdf">https://jaehr.muk.ac.ir/article_242850_5951daaeb462b67c3b95388b742dd719.pdf</ArchiveCopySource>
</Article>
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