Review on main sources and impacts of urban ultrafine particles: Traffic emissions, nucleation, and climate modulation

Li, Qin‐Qin; Guo, Yuexin; Yang, Jingyi; Liang, Chun-Sheng

doi:10.1016/j.aeaoa.2023.100221

Cited by 5 publications

(2 citation statements)

References 275 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The spatial and temporal diversity and dynamics of the formation and transformation processes, and of meteorological conditions are reflected in the PNSDs as far as both their integrated concentration and shape are concerned (Li et al, 2023). Thus, size distributions can be used for identifying and quantifying various source types.…”

Section: Introduction and Objectivesmentioning

confidence: 99%

Attribution of aerosol particle number size distributions to major sources using a 11-year-long urban dataset

Vörösmarty,

Hopke,

Salma

2024

Preprint

View full text Add to dashboard Cite

Abstract. Source apportionment was performed using size segregated particle number concentrations (PNCs) in 27 size channels over the diameter range of 6–1000 nm augmented by air pollutants all with a time resolution of 1 h in the urban background of Budapest for 11 full years in separate seasons. The input dataset was corrected for the effect of the local meteorology by dispersion normalization using the ventilation coefficient defined as the planetary boundary mixing layer height multiplied by the wind speed. Both the uncorrected and dispersion-corrected datasets were evaluated using positive matrix factorization. Six source types including nucleation, two road vehicle emission sources separated into a semi-volatile fraction and a solid core fraction, diffuse urban source, secondary inorganic aerosol (SIA), and ozone-associated particles were identified, characterised, and quantified. The ventilation correction substantially modified the input concentrations, while the differences in the corrected-to-uncorrected ratios for the contributions remained within 5 %. The overall mean relative contribution of the road traffic emission sources was 60 %, and did not show considerable seasonal variability. Nucleation was responsible for 20 % of the PNC annually as a lower estimate. It exhibited a compound character consisting of photochemically induced nucleation and traffic-related nucleation. The former process occurs on regional or urban spatial scales around noon, whereas the latter process happens when the gas-phase vapours in the vehicle exhaust cool, and the resulted supersaturated vapours nucleate outside the source. Its relative contributions were maximal in spring (somewhat smaller in summer and autumn) and minimal in winter. The contributions from the SIA and the urban diffuse source types were approximately 10 % in spring, summer, and 12–15 % in autumn and winter, respectively. The O3-associated secondary aerosol made up the smallest (6 %) portion of particles on an annual basis. Directionality variations investigated by conditional bivariate probability function analysis were used to locate the likely source areas, and showed considerable spatial variations in the source origin.

show abstract

Section: Introduction and Objectivesmentioning

confidence: 99%

Attribution of aerosol particle number size distributions to major sources using a 11-year-long urban dataset

Vörösmarty,

Hopke,

Salma

2024

Preprint

View full text Add to dashboard Cite

show abstract

“…They proposed that the DPF do no retain semi-volatile organic compounds (SVOCs) emitted by diesel cars, and the nucleation of these SVOCs and the abatement of the condensation sink (CS) might account for the non-decreasing trend of the Nucleation mode. Furthermore, abrasion UFP are also emitted as part of the non-exhaust vehicle emissions (Dahl et al, 2006;Mathissen et al, 2011;Niemann et al, 2020;Li et al, 2023;and references therein).…”

Section: Introductionmentioning

confidence: 99%