{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,31]],"date-time":"2025-12-31T20:16:55Z","timestamp":1767212215153,"version":"build-2065373602"},"reference-count":36,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,7,16]],"date-time":"2025-07-16T00:00:00Z","timestamp":1752624000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["101131631","14\/2016"],"award-info":[{"award-number":["101131631","14\/2016"]}]},{"name":"UniversaPulsar, GRASP-Synergy","award":["101131631","14\/2016"],"award-info":[{"award-number":["101131631","14\/2016"]}]},{"name":"The Moroccan Ministry for Higher Education, Scientific Research, and Innovation","award":["101131631","14\/2016"],"award-info":[{"award-number":["101131631","14\/2016"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Environments"],"abstract":"<jats:p>The worldwide air pollution situation reveals significant environmental challenges. In addition to being a major contributor to the deterioration of air quality, particulate matter (PM) is also an important factor affecting the performance of solar energy systems given its ability to decrease light transmission to solar panels. As part of our research, the present investigation involves monitoring concentrations of PM using a high-performance optical instrument, the in situ calibration protocol of which is described in detail. For the city of Rabat, observations revealed significant variations in concentrations between day and night, with peaks observed around 8 p.m. correlating with high relative humidity and low wind speeds, and the highest levels recorded in February with a monthly average value reaching 75 \u00b5m\/m3. In addition, an experimental protocol was set up for an analysis of the elemental composition of particles in the same city using SEM\/EDS, providing a better understanding of their morphology. To assess the impact of meteorological variables on PM concentrations in two distinct climatic environments, a database from the city of Marrakech for the year 2024 was utilized. Overall, the distribution of PM values during this period did not fluctuate significantly, with a monthly average value not exceeding 45 \u00b5m\/m3. The random forest method identified the most influential variables on these concentrations, highlighting the strong influence of the type of environment. The findings provide crucial information for the modeling of solar installations\u2019 soiling and for improving understanding of local air quality.<\/jats:p>","DOI":"10.3390\/environments12070244","type":"journal-article","created":{"date-parts":[[2025,7,16]],"date-time":"2025-07-16T15:48:22Z","timestamp":1752680902000},"page":"244","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Optical Monitoring of Particulate Matter: Calibration Approach, Seasonal and Diurnal Dependency, and Impact of Meteorological Vectors"],"prefix":"10.3390","volume":"12","author":[{"given":"Salma","family":"Zaim","sequence":"first","affiliation":[{"name":"Thermodynamic Energy Laboratory (LTE), Faculty of Sciences, Mohammed V University in Rabat, Rabat 10000, Morocco"},{"name":"Physics of Semiconductors and Solar Energy Research Team (PSES), Energy Research Center (CRE), Ecole Normale Sup\u00e9rieure, Mohammed V University in Rabat, Rabat 10000, Morocco"},{"name":"Instrumentation and Control Laboratory-LAICA, Center for Sci-Tech Research in Earth System and Energy-CREATE, University of Evora, 7000-671 Evora, Portugal"}]},{"given":"Bouchra","family":"Laarabi","sequence":"additional","affiliation":[{"name":"Physics of Semiconductors and Solar Energy Research Team (PSES), Energy Research Center (CRE), Ecole Normale Sup\u00e9rieure, Mohammed V University in Rabat, Rabat 10000, Morocco"}]},{"given":"Hajar","family":"Chamali","sequence":"additional","affiliation":[{"name":"Physics of Semiconductors and Solar Energy Research Team (PSES), Energy Research Center (CRE), Ecole Normale Sup\u00e9rieure, Mohammed V University in Rabat, Rabat 10000, Morocco"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2857-8870","authenticated-orcid":false,"given":"Abdelouahed","family":"Dahrouch","sequence":"additional","affiliation":[{"name":"Royal Gendarmerie Forensic Science Institute, Rabat 10000, Morocco"}]},{"given":"Asmae","family":"Arbaoui","sequence":"additional","affiliation":[{"name":"Thermodynamic Energy Laboratory (LTE), Faculty of Sciences, Mohammed V University in Rabat, Rabat 10000, Morocco"},{"name":"Physics of Semiconductors and Solar Energy Research Team (PSES), Energy Research Center (CRE), Ecole Normale Sup\u00e9rieure, Mohammed V University in Rabat, Rabat 10000, Morocco"}]},{"given":"Khalid","family":"Rahmani","sequence":"additional","affiliation":[{"name":"Physics of Semiconductors and Solar Energy Research Team (PSES), Energy Research Center (CRE), Ecole Normale Sup\u00e9rieure, Mohammed V University in Rabat, Rabat 10000, Morocco"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2542-5318","authenticated-orcid":false,"given":"Abdelfettah","family":"Barhdadi","sequence":"additional","affiliation":[{"name":"Physics of Semiconductors and Solar Energy Research Team (PSES), Energy Research Center (CRE), Ecole Normale Sup\u00e9rieure, Mohammed V University in Rabat, Rabat 10000, Morocco"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8026-1988","authenticated-orcid":false,"given":"Mouhaydine","family":"Tlem\u00e7ani","sequence":"additional","affiliation":[{"name":"Instrumentation and Control Laboratory-LAICA, Center for Sci-Tech Research in Earth System and Energy-CREATE, University of Evora, 7000-671 Evora, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1169398","DOI":"10.1016\/j.jece.2025.116398","article-title":"Pollution characteristics and control strategies of typical waste plastic recycling plants","volume":"13","author":"Guan","year":"2025","journal-title":"J. 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