Assessment of Tropospheric Sulfur Dioxide and Nitrogen Dioxide in Aba Metropolis, Abia State South Eastern, Nigeria. A Case Study of 2019-2024

Assessment of Tropospheric Sulfur Dioxide and Nitrogen Dioxide in Aba Metropolis, Abia State South Eastern, Nigeria. A Case Study of 2019-2024 | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Assessment of Tropospheric Sulfur Dioxide and Nitrogen Dioxide in Aba Metropolis, Abia State South Eastern, Nigeria. A Case Study of 2019-2024 Desmond Onyedika Okoye This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9467885/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Sulfur dioxide and nitrogen dioxide levels in Aba, Abia State, were examined from 2019 to 2024 to understand temporal and spatial air quality trends influenced by industrial, vehicular, and policy factors. Sentinel-5P satellite data were processed in Google Earth Engine and ArcGIS, producing spatial distribution maps and descriptive statistics. The analysis revealed marked fluctuations corresponding to major socio-economic and environmental events. Sulfur dioxide recorded a sharp decline in 2020 (mean − 0.0000511 mol/m²) following COVID-19 lockdowns, peaked in 2021 (0.0000163 mol/m²) as industries reopened, and stabilized after 2023 due to the fuel subsidy removal. Spatial hotspots contracted from widespread zones in 2021 to small industrial pockets in Aba South by 2024. Nitrogen dioxide followed a gradual rise from 2019 (0.0000632 mol/m²) to a 2021 maximum (0.0000738 mol/m²), then declined steadily to 0.0000662 mol/m² in 2024, reflecting reduced transport activity and emission control impacts. Spatially, persistent high concentrations remained around Aba North, especially near Aba International Market and Owerri Road, while southern areas showed improvement. The t-test confirmed statistically significant differences across years, affirming the influence of lockdown restrictions and national fuel policies on pollutant behavior. Findings indicate improved air quality relative to pre-pandemic baselines, though localized hotspots persist. Strengthened regulatory enforcement, cleaner production technologies, expansion of ground-based monitoring, and traffic management reforms are recommended to sustain the gains. The study demonstrates how integrated satellite analysis and policy evaluation can guide urban air quality management and sustainable environmental planning in rapidly growing Nigerian cities. Environmental Policy Air Quality Remote Sensing Sentinel 5P Sulfur dioxide Nitrogen dioxide Full Text Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9467885","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":626035088,"identity":"36ce1da3-c02f-43a6-9f6b-ec90f16c3ca5","order_by":0,"name":"Desmond Onyedika Okoye","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/0lEQVRIiWNgGAWjYDCCA2CSmUECRH2osAGSjI0HiNbCOONMGohqIF4LM2/bYSRBHIDvePvTDR93WMtJtvcYPpxx5rzd2vbDQFtqbKJxaZE8c8bs5swz6cbSPGeMDT5U3E7ediYRqOVYWm4DDi0GN3LYbgPdkzhPIsdMcsaZ28lmB4BaGBsO49Zy//kzmBbz37xt55LNzj8koOUGgxlYy2ygLUDvH7Azu0HAFskzOUC/tKUbS/YcKwY6LDnB7AbQlgQ8fuE7fvzZjY9t1nISx5s3fvhQYWdvdj794YMPNTY4tSABDgMQmQhWmUBYOQiwPwCR9sQpHgWjYBSMgpEEAH33bi+MAdICAAAAAElFTkSuQmCC","orcid":"","institution":"University of Benin","correspondingAuthor":true,"prefix":"","firstName":"Desmond","middleName":"Onyedika","lastName":"Okoye","suffix":""}],"badges":[],"createdAt":"2026-04-20 06:45:46","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":true,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":true},"doi":"10.21203/rs.3.rs-9467885/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9467885/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":107487935,"identity":"b14bccf4-2df4-4ea0-b99b-79203f26ffb1","added_by":"auto","created_at":"2026-04-22 02:43:06","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2689455,"visible":true,"origin":"","legend":"","description":"","filename":"DesmondAbiaManuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9467885/v1_covered_cf9fba64-fe74-45e4-b166-dc7dd730c857.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eAssessment of Tropospheric Sulfur Dioxide and Nitrogen Dioxide in Aba Metropolis, Abia State South Eastern, Nigeria. 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