![]() ![]() Our results indicate that biomass burning might affect the atmosphere on a regional scale, contribute to regional warming, and have implications for local and regional air quality and, therefore, human health. Biomass burning events are a relevant contributing source of aerosols for both sites of measurements inferred by fire pixels from satellite data, the national fire department’s statistics data, and backward trajectories. CBPF showed seasonal variations of eBC and PM 2.5 sources and that their contributions are higher during the dry season. eBC and PM 2.5 sources identification during wet and dry seasons was obtained by percentiles of the conditional bivariate probability function (CBPF). To our knowledge, these are the first measurements of this type in the northernmost area of South America. The annual median for eBC and PM 2.5 was 1.6 and 9.2 µg m –3, respectively, in the urban site, while PM 2.5 in the forest site was 6.6 µg m –3. In the forest site, PM 2.5 values were higher in the afternoons due to the convective transport of aerosols from Caracas and other surrounding urban areas located in adjacent valleys. In contrast, PM 2.5 showed stable median values during the day with slight variations like that of eBC. eBC showed a pronounced diurnal cycle in the urban site, mainly modulated by traffic circulation and the diurnal changes of the mixing layer height. Our goal is to assess PM 2.5 and eBC temporal variation and identify their major sources in the area. ![]() We also measured equivalent black carbon (eBC) mass concentration in PM 2.5 in Caracas during the same period. In this study, we measured the mass concentration of atmospheric aerosols with an aerodynamic diameter smaller than 2.5 µm (PM 2.5) in the city of Caracas (urban) and in a tropical montane cloud forest (suburban site, located in a mountainous area 11 km far from Caracas) between June 2018 and October 2019. Characterizing atmospheric aerosols and identifying their sources in large cities is relevant to propose site-specific air pollution mitigation strategies. Atmospheric aerosols play an important role in atmospheric processes and human health. ![]()
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