{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T11:58:09Z","timestamp":1784030289264,"version":"3.55.0"},"reference-count":48,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2022,12,19]],"date-time":"2022-12-19T00:00:00Z","timestamp":1671408000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002848","name":"ANID","doi-asserted-by":"publisher","award":["FONDAP 15110020"],"award-info":[{"award-number":["FONDAP 15110020"]}],"id":[{"id":"10.13039\/501100002848","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002848","name":"ANID","doi-asserted-by":"publisher","award":["Fondecyt 1980894"],"award-info":[{"award-number":["Fondecyt 1980894"]}],"id":[{"id":"10.13039\/501100002848","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Background: The SARS-CoV-2 pandemic has temporarily decreased black carbon emissions worldwide. The use of multi-wavelength aethalometers provides a quantitative apportionment of black carbon (BC) from fossil fuels (BCff) and wood-burning sources (BCwb). However, this apportionment is aggregated: local and non-local BC sources are lumped together in the aethalometer results. Methods: We propose a spatiotemporal analysis of BC results along with meteorological data, using a fuzzy clustering approach, to resolve local and non-local BC contributions. We apply this methodology to BC measurements taken at an urban site in Santiago, Chile, from March through December 2020, including lockdown periods of different intensities. Results: BCff accounts for 85% of total BC; there was up to an 80% reduction in total BC during the most restrictive lockdowns (April\u2013June); the reduction was 40\u201350% in periods with less restrictive lockdowns. The new methodology can apportion BCff and BCwb into local and non-local contributions; local traffic (wood burning) sources account for 66% (86%) of BCff (BCwb). Conclusions: The intensive lockdowns brought down ambient BC across the city. The proposed fuzzy clustering methodology can resolve local and non-local contributions to BC in urban zones.<\/jats:p>","DOI":"10.3390\/ijerph192417064","type":"journal-article","created":{"date-parts":[[2022,12,19]],"date-time":"2022-12-19T05:55:43Z","timestamp":1671429343000},"page":"17064","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Spatiotemporal Analysis of Black Carbon Sources: Case of Santiago, Chile, under SARS-CoV-2 Lockdowns"],"prefix":"10.3390","volume":"19","author":[{"given":"Carla","family":"Adasme","sequence":"first","affiliation":[{"name":"Departamento de Ingenier\u00eda Qu\u00edmica y Bioprocesos, Pontificia Universidad Cat\u00f3lica de Chile, Santiago 7820436, Chile"},{"name":"Centro de Desarrollo Urbano Sustentable (CEDEUS), Los Navegantes 1963, Providencia, Santiago 7520246, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana Mar\u00eda","family":"Villalobos","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Qu\u00edmica y Bioprocesos, Pontificia Universidad Cat\u00f3lica de Chile, Santiago 7820436, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7462-7901","authenticated-orcid":false,"given":"H\u00e9ctor","family":"Jorquera","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Qu\u00edmica y Bioprocesos, Pontificia Universidad Cat\u00f3lica de Chile, Santiago 7820436, Chile"},{"name":"Centro de Desarrollo Urbano Sustentable (CEDEUS), Los Navegantes 1963, Providencia, Santiago 7520246, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"106346","DOI":"10.1016\/j.envint.2020.106346","article-title":"Short-term association of in-vehicle ultrafine particles and black carbon concentrations with respiratory health in Parisian taxi drivers","volume":"147","author":"Hachem","year":"2021","journal-title":"Environ. 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