A review of aerosol chemistry in Asia: insights from aerosol mass spectrometer measurements

Environmental Science Processes & Impacts, Journal Year: 2020, Volume and Issue: 22(8), P. 1616 - 1653

Published: Jan. 1, 2020

Aerosol mass spectrometer has been widely deployed in Asia for real-time characterization of aerosol chemistry, and significantly improved our understanding the sources, properties, formation processes aerosols a complex environment.

Language: Английский

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Light Absorbing Properties of Primary and Secondary Brown Carbon in a Tropical Urban Environment

Environmental Science & Technology, Journal Year: 2020, Volume and Issue: 54(17), P. 10808 - 10819

Published: July 27, 2020

Brown carbon (BrC) has significant climatic impact, but its emission sources and formation processes remain under-represented in climate models. However, there are only limited field studies to quantify the light absorption properties of specific types primary secondary organic aerosols (POAs SOAs) different environments. This work investigates major OA components Singapore, a well-developed city tropical region, where air quality can be influenced by multiple local urban regional biomass burning events. The source-specific mass cross-section (MAC) wavelength dependence BrC were quantified based on highly time-resolved aerosol chemical composition measurements. In particular, combustion-related contributors they moderately absorbing. SOA materials, which freshly formed under atmospheric conditions with industrial influences, also absorptive. aged that composed emissions, including coal combustion emissions from nearby regions, weakly absorbing, highlighting possibility photobleaching during their aging dispersion. Lastly, our estimations illustrate typical POAs SOAs contribute up approximately 36–58% absorption, even some locations emissions.

Language: Английский

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Sources of black carbon at residential and traffic environments obtained by two source apportionment methods

Atmospheric chemistry and physics, Journal Year: 2021, Volume and Issue: 21(19), P. 14851 - 14869

Published: Oct. 6, 2021

Abstract. This study investigated the sources of black carbon (BC) at two contrasting urban environments in Helsinki, Finland: residential area and street canyon. The measurement campaign was conducted winter–spring 2019, whereas canyon measurements were carried out autumn 2015. BC explored by using positive matrix factorization (PMF) for organic refractory (rBC) mass spectra collected with a soot particle aerosol spectrometer (SP-AMS). Based on PMF analysis, sites had different local sources; largest fraction originated from biomass burning site (38 %) vehicular emissions (57 %). Also, size distribution diverged as traffic found ∼100–150 nm combustion detected ∼300 nm. At both sites, large associated background or long-range-transported indicated high oxidation state organics related to those factors. results analysis compared source apportionment Aethalometer model calculated pairs absorption Ångström values. It that several factors can be attributed wood fossil fuel provided model. In general, showed less variation between within day than PMF, indicating it responsive fast changes site, could not distinguish many due similar optical properties sources. this increase understanding limitations validity methods environments. Moreover, advances current knowledge especially contribution areas.

Language: Английский

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Impact of urbanization on fine particulate matter concentrations over central Europe

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(1), P. 397 - 425

Published: Jan. 11, 2024

Abstract. Rural-to-urban transformation (RUT) is the process of turning a rural or natural land surface into an urban one, which brings about important modifications in surface, causing well-known effects like heat island (UHI), reduced wind speeds, and increased boundary layer heights. Moreover, with concentrated human activities, RUT introduces new emission sources greatly perturb local regional air pollution. Particulate matter (PM) one key pollutants responsible for deterioration quality still major issue European cities, frequent exceedances limit values. Here we introduce chemistry–climate model (regional climate RegCM coupled offline to chemistry transport CAMx) study quantifies how modified PM concentrations over central Europe including underlying controlling mechanisms that contribute final Apart from two most studied ones, (i) emissions (ii) canopy meteorological forcing (UCMF; i.e. impact conditions on quality), also analyse less contributors RUT's quality: (iii) dry-deposition velocities (DVs) due urbanized use (iv) biogenic urbanization-induced vegetation changes affect these emissions. To calculate magnitude each contributors, perform cascade simulations, whereby contributor added by reference state, while focus given PM2.5 (particulate diameter then 2.5 µm). Its primary secondary components, namely elemental carbon (PEC), sulfates (PSO4), nitrates (PNO3), ammonium (PNH4), organic aerosol (SOA), are analysed too. The validation using measurements showed systematic negative bias total PM2.5, probably caused underestimated partly carbon. For nitrates, underestimation limited warm season, winter, tends overestimate their concentrations. However, case, annual cycle reasonably captured. We evaluated sample 19 cities found urbanization 2–3 1–1.5 µg m−3 winter summer, respectively. This mainly driven alone slightly higher (1.5–3.5 1.2–2 summer), effect UCMF was decrease at 0.2–0.5 (in both seasons), controlled enhanced vertical eddy diffusion, increases were modelled areas. increase around 30 %–50 %, resulted 0.1–0.25 seasons. Finally, summer 0.1 m−3, negligible. components be (values indicate averages) 0.4 0.3 PEC, 0.05 0.02 PSO4, 0.08 PNO3, 0.04 0.03 PNH4, 0 SOA. main emissions, usually larger than fact counteracted decrease. component, DV clear concentration, finally, impacted SOA predominantly, decrease, very small inorganic too (they increased). In summary, when analysing pollution, apart forcing, has consider its dry deposition. These shown our calculations they act predominantly through modifications, only turned out during summer.

Language: Английский

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Variations and Sources of Organic Aerosol in Winter Beijing under Markedly Reduced Anthropogenic Activities During COVID-2019

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 56(11), P. 6956 - 6967

Published: Nov. 17, 2021

The COVID-19 outbreak provides a "controlled experiment" to investigate the response of aerosol pollution reduction anthropogenic activities. Here we explore chemical characteristics, variations, and emission sources organic (OA) based on observation air pollutants combination mass spectrometer (AMS) positive matrix factorization (PMF) analysis in Beijing early 2020. By eliminating impacts atmospheric boundary layer Spring Festival, found that lockdown effectively reduced cooking-related OA (COA) but influenced fossil fuel combustion (FFOA) very little. In contrast, both secondary (SOA) O3 formation was enhanced significantly after lockdown: less-oxidized oxygenated (LO-OOA, 37% OA) probably an aged product from biomass burning with aqueous chemistry being important pathway, while more-oxidized (MO-OOA, 41% affected by regional transport related photochemical processes. Combining FFOA LO-OOA, more than 50% attributed activities during whole period. Our findings highlight fuel/biomass are still largest pollution, only controlling traffic cooking emissions cannot efficiently eliminate heavy winter Beijing.

Language: Английский

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Seasonal variation of aerosol compositions in Shanghai, China: Insights from particle aerosol mass spectrometer observations

The Science of The Total Environment, Journal Year: 2021, Volume and Issue: 771, P. 144948 - 144948

Published: Jan. 29, 2021

Language: Английский

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Chemical properties, sources and size-resolved hygroscopicity of submicron black-carbon-containing aerosols in urban Shanghai

Atmospheric chemistry and physics, Journal Year: 2022, Volume and Issue: 22(12), P. 8073 - 8096

Published: June 22, 2022

Abstract. Refractory black carbon (rBC) aerosols play an important role in air quality and climate change, yet highly time-resolved detailed investigations on the physicochemical properties of rBC its associated coating are still scarce. In this work, we used a laser-only Aerodyne soot particle aerosol mass spectrometer (SP-AMS) to exclusively measure rBC-containing (rBCc) particles, compared their with those total nonrefractory submicron particles (NR-PM1) measured parallel by high-resolution AMS (HR-AMS) Shanghai. Observations showed that, overall, was thickly coated, average ratio core (RBC) ∼5.0 (±1.7). However, rBC-coating species NR-PM1 only 19.1 (±4.9) %; sulfate tended condense preferentially non-rBC so 7.4 (±2.2) %, while majority (72.7±21.0 %) primary organic (POA) were rBC. Positive matrix factorization revealed that organics emitted from cooking did not coat rBC, portion coated biomass burning; such unidentifiable NR-PM1. Small rBCc predominantly traffic, large-sized ones often mixed secondary components typically had thick coating. Sulfate (SOA) generated mainly through daytime photochemical oxidation (SOA formation, likely situ chemical conversion traffic-related POA SOA), nocturnal heterogeneous formation dominant for nitrate; also estimated time 5–19 h During short period affected ship emissions, characterized as having high vanadium concentration (on 6.3±3.1 ng m−3) mean vanadium/nickel 2.0 (±0.6). Furthermore, size-resolved hygroscopicity parameter (κrBCc) obtained based full characterization, parameterized κrBCc(x)=0.29–0.14 × exp⁡(-0.006×x) (where x ranges 150 1000 nm). Under critical supersaturations (SSC) 0.1 % 0.2 D50 values 166 (±16) 110 (±5) nm, respectively, 16 (±3) 59 (±4) number could be activated into cloud condensation nuclei (CCN). Our findings valuable advancing understanding BC chemistry well effective control atmospheric pollution.

Language: Английский

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Oxidative potential induced by metal-organic interaction from PM2.5 in simulated biological fluids

The Science of The Total Environment, Journal Year: 2022, Volume and Issue: 848, P. 157768 - 157768

Published: Aug. 3, 2022

Language: Английский

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Aqueous aging of secondary organic aerosol coating onto black carbon: Insights from simultaneous L-ToF-AMS and SP-AMS measurements at an urban site in southern China

Journal of Cleaner Production, Journal Year: 2021, Volume and Issue: 330, P. 129888 - 129888

Published: Nov. 27, 2021

Language: Английский

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Analysis of black carbon in environmental and biological media: Recent progresses and challenges

TrAC Trends in Analytical Chemistry, Journal Year: 2023, Volume and Issue: 169, P. 117347 - 117347

Published: Oct. 6, 2023

Language: Английский

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