Anthropogenic emissions are the result of many different activities, related to transportation, power generation, industrial, residential and commercial activities, waste treatment and agriculture ...practices. Air quality models are used to forecast the atmospheric composition, analyse observations and reconstruct the chemical composition of the atmosphere during the previous decades. In order to drive these models, gridded emissions of all compounds emitted at the surface need to be provided. This paper describes a new global inventory of emissions called CAMS-GLOB-ANT, developed as part of the Copernicus Atmosphere Monitoring Service (CAMS). The inventory provides monthly averages of the global emissions of 36 compounds, including the main air pollutants and greenhouse gases, at a spatial resolution of 0.1x0.1 degree in latitude and longitude, for 17 emission sectors. The methodology to generate the emissions for the 2000–2023 period is explained, and the datasets are analysed and compared with publicly available global and regional inventories for selected world regions.
Particulate Matter (PM) Low-Cost Sensors (LCS) can be used to monitor air quality in regions with limited access to reference monitors. This study carried out within the framework of the Improving ...Air Quality in West Africa (IAQWA) project provides high temporal resolution of data on fine aerosol (PM2.5) mass concentrations in Abidjan (Cote d'Ivoire) and Accra (Ghana) through the deployment of field calibratedReal-time Affordable Multi-pollutant (RAMP) monitors. From February 2020 to June 2021, RAMPs were deployed at five sites in Abidjan and four sites in Accra. Using a temporal resolution of 15 seconds, the datasets provided by RAMPs allowed a comparative analysis of diurnal, daily and seasonal variability of PM2.5 concentrations for different urban sites with distinct pollution sources, over an extended period oftime. Diurnal variations in PM2.5 concentrations showed prominent morning peaks related to traffic rush hours reaching up to 50 mg m−3 . Evening peaks were significant for sites in residential neighborhoods, and pointed to residential type pollution sources. Seasonal differences are analysed over a yearly cycle and maximum values are found during the so-called long dry season (Harmattan), between December and February. During a prominent pollution episode in January 2021 observed by the ground network,analysis of 3D satellite data, revealed Saharan dust transport as an additional source of (fine) aerosol pollution significantly increasing PM2.5. The same episode also revealed a limitation of LCS – an inability to adequately capture dust-dominated pollution, which can be quantified by reference monitors. Annual average PM2.5 concentrations vary between 17 and 26 mg m−3 . PM2.5 differences between sites within a city, especially between traffic impacted and urban background sites, are larger than the differencesbetween the two cities. These annual averages exceed World Health Organization (WHO) annual pollution thresholds from the 2005 (10 mg m−3) and 2021 (5 mg m−3) guidelines.
Les capteurs de particules (PM) à faible coût (LCS) peuvent être utilisés pour surveiller la qualité de l'air dans les régions ayant un accès limité aux moniteurs de référence. Cette étude réalisée dans le cadre du projet d'amélioration de la qualité de l'air en Afrique de l'Ouest (IAQWA) fournit des données à haute résolution temporelle sur les concentrations massiques d'aérosols fins (PM 2,5 ) à Abidjan (Côte d'Ivoire) et à Accra (Ghana) grâce au déploiement de moniteurs RAMP (Real Time Affordable Multi-polluants) étalonnés sur le terrain. De février 2020 à juin 2021, des RAMP ont été déployés sur cinq sites à Abidjan et quatre sites à Accra. Utilisant une résolution temporelle de 15 secondes, les ensembles de données fournis par RAMP ont permis une analyse comparative de la variabilité diurne, quotidienne et saisonnière des concentrations de PM 2,5 pour différents sites urbains avec des sources de pollution distinctes, sur une période de temps prolongée. Les variations diurnes des concentrations de PM 2,5 ont montré des pics matinaux importants liés aux heures de pointe de la circulation, atteignant jusqu'à 50 μg m −3 . Les pointes nocturnes étaient significatives pour les sites situés dans des quartiers résidentiels et pointaient vers des sources de pollution de type résidentiel. Les différences saisonnières sont analysées sur un cycle annuel et les valeurs maximales sont trouvées pendant la longue saison sèche (Harmattan), entre décembre et février. Lors d'un épisode de pollution important en janvier 2021 observé par le réseau terrestre, l'analyse des données satellitaires 3D a révélé que le transport de poussières sahariennes était une source supplémentaire de pollution par aérosols (fins) augmentant considérablement les PM 2,5 . Le même épisode a également révélé une limitation du LCS – une incapacité à capturer de manière adéquate la pollution dominée par la poussière, qui peut être quantifiée par des moniteurs de référence. Les concentrations annuelles moyennes de PM 2,5 varient entre 17 et 26 μg m −3 . Les différences de PM 2,5 entre les sites d’une même ville, en particulier entre les sites impactés par la circulation et les sites urbains, sont plus importantes que les différences entre les deux villes. Ces moyennes annuelles dépassent les seuils de pollution annuels de l'Organisation mondiale de la santé (OMS) des lignes directrices de 2005 (10 μg m −3 ) et 2021 (5 μg m −3 ).
As part of the Air Pollution and Health in Urban Environments (PASMU) project, equipment was installed in urban sites of Abidjan and Korhogo (Ivory Coast) in West Africa with the aim of monitoring ...the chemical composition of PM
2.5
aerosols. These installations were used to collect PM
2.5
aerosols at weekly intervals for the determination of their PM
2.5
mass, EC, OC and water-soluble ions (WSI). This database enabled us to analyse the 2 year trend (2018-2020) of the chemical composition of PM
2.5
aerosols in these two cities. In addition, this database was used to assess the sources of these aerosols using both PCA (principal component analysis) and the US Environmental Protection Agency's EPA PMF 5.0 software. The results showed that the PM
2.5
concentrations observed during the 2 dry seasons were more than twice than that during the 2 wet seasons. Also, over the 2 year study period, the observed PM
2.5
concentrations were above the WHO, 2021 standards. The analysis of the chemical composition of PM
2.5
showed that organic matter (OM) was the major fraction in the 2 cities, followed by EC in Abidjan and dust in Korhogo. Similarly, the observed trends showed greater variations in OC concentrations between the dry and wet seasons compared with EC. Also, 5 contributing sources were identified with disproportionate contributions. In Abidjan, these sources included road traffic (44.7%), domestic fires (40%), natural and road dust (11.2%), sea salt (3%), and construction dust (1.2%). In Korhogo, the sources were biomass burning and domestic fires (70.7%), road traffic (16%), road dust and sea salt (8.1%), natural dust (2.6%), and agriculture (2.5%). This study offers vital insights into identifying the primary sources of urban air pollution in West African cities. Consequently, tailored strategies based on these sources can effectively mitigate urban particulate pollution, leading to reduced emissions, enhanced air quality, and improved public health in densely populated urban regions.
As part of PASMU project, equipment was installed in urban sites of Abidjan and Korhogo (Cote d'Ivoire) in West Africa with the aim of studying the chemical composition of PM
2.5
aerosols and identifying the contributing emissions sources.
The involvement of particulate matter (PM) in cardiorespiratory diseases is now established in developed countries whereas in developing areas such as Africa with a high level of specific pollution, ...PM pollution and its effects are poorly studied. Our objective was to characterize the biological reactivity of urban African aerosols on human bronchial epithelial cells in relation to PM physico-chemical properties to identify toxic sources.
Size-speciated aerosol chemical composition was analyzed in Bamako (BK, Mali, 2 samples with one having desert dust event BK1) and Dakar (DK; Senegal) for Ultrafine UF, Fine F and Coarse C PM. PM reactivity was studied in human bronchial epithelial cells investigating six biomarkers (oxidative stress responsive genes and pro-inflammatory cytokines).
PM mass concentrations were mainly distributed in coarse mode (60%) and were impressive in BK1 due to the desert dust event. BK2 and DK samples showed a high content of total carbon characteristic of urban areas. The DK sample had huge PAH quantities in bulk aerosol compared with BK that had more water soluble organic carbon and metals. Whatever the site, UF and F PM triggered the mRNA expression of the different biomarkers whereas coarse PM had little or no effect. The GM-CSF biomarker was the most discriminating and showed the strongest pro-inflammatory effect of BK2 PM. The analysis of gene expression signature and of their correlation with main PM compounds revealed that PM-induced responses are mainly related to organic compounds. The toxicity of African aerosols is carried by the finest PM as with Parisian aerosols, but when considering PM mass concentrations, the African population is more highly exposed to toxic particulate pollution than French population. Regarding the prevailing sources in each site, aerosol biological impacts are higher for incomplete combustion sources resulting from two-wheel vehicles and domestic fires than from diesel vehicles (Dakar). Desert dust events seem to produce fewer biological impacts than anthropogenic sources.
Our study shows that combustion sources contribute to the high toxicity of F and UF PM of African urban aerosols, and underlines the importance of emission mitigation and the imperative need to evaluate and to regulate particulate pollution in Africa.
The “Expérience sur Site pour COntraindre les Modèles de Pollution atmosphérique et de Transport d'Emissions” (ESCOMPTE) experiment took place in the Southern part of France in the ...Marseilles/Fos-Berre region during 6 weeks in June and July 2001. One task was to document the regional sources of atmospheric particles and to gain some insight into the aerosol transformations in the atmosphere. For this purpose, seven sites were chosen and equipped with the same basic instrumentation to obtain the chemical closure of the bulk aerosol phase and size-segregated samples. Some specific additional experiments were conducted for the speciation of the organic matter and the aerosol size distribution in number. Finally, four multiwavelength sun-photometers were also deployed during the experiment.
Interestingly, in this region, three intense aerosol sources (urban, industrial and biogenic) are very active, and data show consistent results, enlightening an important background of particles over the whole ESCOMPTE domain. Notable is the overwhelming importance of the carbonaceous fraction (comprising primary and secondary particles), which is always more abundant than sulphates. Particle size studies show that, on average, more than 90% of the mean regional aerosol number is found on a size range smaller than 300 nm in diameter.
The most original result is the evidence of the rapid formation of secondary aerosols occurring in the whole ESCOMPTE domain. This formation is much more important than that usually observed at these latitudes since two thirds of the particulate mass collected off source zones is estimated to be generated during atmospheric transport. On the other hand, the marine source has poor influence in the region, especially during the overlapping pollution events of Intensive Observation Periods (IOP).
Preliminary results from the 0D and 3D versions of the MesoNH-aerosol model show that, with optimised gas and particle sources, the model accounts satisfactorily for the measured aerosol concentrations. The formation of secondary particles in the model is currently underway; initial encouraging results show that the model accounts for the formation of secondary species, such as sulphate and organic particles. Finally, radiative calculations suggest that the role of the fine aerosol fraction is predominant mostly due to the presence of black carbon (BC) particles, which could induce a regional atmospheric heating.
The authors present results obtained during the chemistry-transport modeling (CTM) component of the African Monsoon Multidisciplinary Analysis Multimodel Intercomparison Project (AMMA-MIP) using the ...recently developed L3JRCv2 emission dataset for Africa, where emphasis is placed on the summer of 2006. With the use of passive tracers, the authors show that the application of different parameterizations to describe advection, vertical diffusion, and convective mixing in a suite of state-of-the-art global CTMs results in significantly different transport mechanisms westward of the African continent. Moreover, the authors identify that the atmospheric composition over the southern Atlantic is governed by air masses originating from southern Africa for this period, resulting in maximal concentrations around 5°S. Comparisons with ozonesonde measurements at Cotonou (6.2°N, 2.2°E) indicate that the models generally overpredict surface ozone and underpredict ozone in the upper troposphere. Moreover, using recent aircraft measurements, the authors show that the high ozone concentrations that occur around 700 hPa around 5°N are not captured by any of the models, indicating shortcomings in the description of transport, the magnitude and/or location of emissions, or the in situ chemical ozone production by the various chemical mechanisms employed.
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Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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