{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:30:13Z","timestamp":1760239813119,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,12,23]],"date-time":"2020-12-23T00:00:00Z","timestamp":1608681600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/00511\/2020","IF\/01341\/2015"],"award-info":[{"award-number":["UIDB\/00511\/2020","IF\/01341\/2015"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Atmosphere"],"abstract":"<jats:p>North African dust intrusions can contribute to exceedances of the European PM10 and PM2.5 limit values and World Health Organisation standards, diminishing air quality, and increased mortality and morbidity at higher concentrations. In this study, the contribution of North African dust in Mediterranean countries was estimated using the time series clustering method. This method combines the non-parametric approach of Hidden Markov Models for studying time series, and the definition of different air pollution profiles (regimes of concentration). Using this approach, PM10 and PM2.5 time series obtained at background monitoring stations from seven countries were analysed from 2015 to 2018. The average characteristic contributions to PM10 were estimated as 11.6 \u00b1 10.3 \u00b5g\u00b7m\u22123 (Bosnia and Herzegovina), 8.8 \u00b1 7.5 \u00b5g\u00b7m\u22123 (Spain), 7.0 \u00b1 6.2 \u00b5g\u00b7m\u22123 (France), 8.1 \u00b1 5.9 \u00b5g\u00b7m\u22123 (Croatia), 7.5 \u00b1 5.5 \u00b5g\u00b7m\u22123 (Italy), 8.1 \u00b1 7.0 \u00b5g\u00b7m\u22123 (Portugal), and 17.0 \u00b1 9.8 \u00b5g\u00b7m\u22123 (Turkey). For PM2.5, estimated contributions were 4.1 \u00b1 3.5 \u00b5g\u00b7m\u22123 (Spain), 6.0 \u00b1 4.8 \u00b5g\u00b7m\u22123 (France), 9.1 \u00b1 6.4 \u00b5g\u00b7m\u22123 (Croatia), 5.2 \u00b1 3.8 \u00b5g\u00b7m\u22123 (Italy), 6.0 \u00b1 4.4 \u00b5g\u00b7m\u22123 (Portugal), and 9.0 \u00b1 5.6 \u00b5g\u00b7m\u22123 (Turkey). The observed PM2.5\/PM10 ratios were between 0.36 and 0.69, and their seasonal variation was characterised, presenting higher values in colder months. Principal component analysis enabled the association of background sites based on their estimated PM10 and PM2.5 pollution profiles.<\/jats:p>","DOI":"10.3390\/atmos12010005","type":"journal-article","created":{"date-parts":[[2020,12,23]],"date-time":"2020-12-23T08:38:43Z","timestamp":1608712723000},"page":"5","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Estimation of Particulate Matter Contributions from Desert Outbreaks in Mediterranean Countries (2015\u20132018) Using the Time Series Clustering Method"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4890-547X","authenticated-orcid":false,"given":"\u00c1lvaro","family":"G\u00f3mez-Losada","sequence":"first","affiliation":[{"name":"Departamento de Estad\u00edstica e Investigaci\u00f3n Operativa, Facultad de Matem\u00e1ticas, Universidad de Sevilla, 41012 Sevilla, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2738-5102","authenticated-orcid":false,"given":"Jos\u00e9 C. M.","family":"Pires","sequence":"additional","affiliation":[{"name":"LEPABE\u2014Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,23]]},"reference":[{"key":"ref_1","unstructured":"WHO (2020, November 19). 9 Out of 10 People Worldwide Breathe Polluted Air, But More Countries are Taking Action. Available online: https:\/\/www.who.int\/news-room\/detail\/02-05-2018-9-out-of-10-people-worldwide-breathe-polluted-air-but-more-countries-are-taking-action."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"376","DOI":"10.1016\/j.atmosenv.2014.09.017","article-title":"Air quality status and trends in europe","volume":"98","author":"Guerreiro","year":"2014","journal-title":"Atmos. 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