Role of iodine oxoacids in atmospheric aerosol nucleation

Science, Journal Year: 2021, Volume and Issue: 371(6529), P. 589 - 595

Published: Feb. 4, 2021

Faster than expected Iodine species are one of only a handful atmospheric vapors known to make new aerosol particles, which play central role in controlling the radiative forcing climate. He et al. report experimental evidence from CERN Cosmics Leaving Outdoor Droplets, or CLOUD, chamber demonstrating that iodic acid and iodous rapidly form particles can compete with sulfuric pristine regions. Science , this issue p. 589

Language: Английский

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Is reducing new particle formation a plausible solution to mitigate particulate air pollution in Beijing and other Chinese megacities?

Faraday Discussions, Journal Year: 2020, Volume and Issue: 226, P. 334 - 347

Published: Aug. 26, 2020

Atmospheric gas-to-particle conversion is a crucial or even dominant contributor to haze formation in Chinese megacities terms of aerosol number, surface area and mass. Based on our comprehensive observations Beijing during 15 January 2018-31 March 2019, we are able show that 80-90% the mass (PM2.5) was formed via atmospheric reactions days over 65% number concentration particles resulted from new particle (NPF). Furthermore, faster when subsequent growth newly enhanced. Our findings suggest practice almost all present-day episodes originate NPF, mainly since direct emission primary has considerably decreased recent years. We also reducing rate freshly by factor 3-5 would delay buildup 1-3 days. Actually, this decrease length each episode, so annual could be approximately halved. Such improvement air quality can achieved with targeted reduction gas-phase precursors for dimethyl amine ammonia, further reductions SO2 emissions. anthropogenic organic inorganic precursor emissions slow down newly-formed consequently reduce formation.

Language: Английский

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The Synergistic Role of Sulfuric Acid, Bases, and Oxidized Organics Governing New‐Particle Formation in Beijing

Geophysical Research Letters, Journal Year: 2021, Volume and Issue: 48(7)

Published: March 22, 2021

Abstract Intense and frequent new particle formation (NPF) events have been observed in polluted urban environments, yet the dominant mechanisms are still under debate. To understand key species governing processes of NPF we conducted comprehensive measurements downtown Beijing during January–March, 2018. We performed detailed analyses on sulfuric acid cluster composition budget, as well chemical physical properties oxidized organic molecules (OOMs). Our results demonstrate that fast clustering (H 2 SO 4 ) base triggered events, OOMs further helped grow newly formed particles toward climate‐ health‐relevant sizes. This synergistic role H , species, is likely representative environments where abundant usually co‐exist, with moderately low volatility when produced high NO x concentrations.

Language: Английский

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Sulfuric acid–amine nucleation in urban Beijing

Atmospheric chemistry and physics, Journal Year: 2021, Volume and Issue: 21(4), P. 2457 - 2468

Published: Feb. 18, 2021

Abstract. New particle formation (NPF) is one of the major sources atmospheric ultrafine particles. Due to high aerosol and trace gas concentrations, mechanism governing factors for NPF in polluted boundary layer may be quite different from those clean environments, which however less understood. Herein, based on long-term measurements January 2018 March 2019 Beijing, nucleation influences H2SO4 concentration, amine concentration are quantified. The collision H2SO4–amine clusters found dominating initialize urban Beijing. coagulation scavenging due a factor as it limits new rates. Beijing sometimes limited by low concentrations. Summarizing synergistic effects we elucidate various conditions.

Language: Английский

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Global variability in atmospheric new particle formation mechanisms

Nature, Journal Year: 2024, Volume and Issue: 631(8019), P. 98 - 105

Published: June 12, 2024

A key challenge in aerosol pollution studies and climate change assessment is to understand how atmospheric particles are initially formed

Language: Английский

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Contribution of Atmospheric Oxygenated Organic Compounds to Particle Growth in an Urban Environment

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(20), P. 13646 - 13656

Published: Sept. 29, 2021

Gas-phase oxygenated organic molecules (OOMs) can contribute substantially to the growth of newly formed particles. However, characteristics OOMs and their contributions particle rate are not well understood in urban areas, which have complex anthropogenic emissions atmospheric conditions. We performed long-term measurement gas-phase Beijing during 2018–2019 using nitrate-based chemical ionization mass spectrometry. OOM concentrations showed clear seasonal variations, with highest summer lowest winter. Correspondingly, calculated rates due condensation were summer, followed by spring, autumn, One prominent feature this environment was a high fraction (∼75%) nitrogen-containing OOMs. These contributed only 50–60% total led condensation, owing slightly higher volatility than non-nitrate By comparing observed rates, we that sulfuric acid its clusters main contributors sub-3 nm particles, significantly promoting 3–25 In wintertime Beijing, however, there missing particles above 3 nm, remain be further investigated.

Language: Английский

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Sources and sinks driving sulfuric acid concentrations in contrasting environments: implications on proxy calculations

Atmospheric chemistry and physics, Journal Year: 2020, Volume and Issue: 20(20), P. 11747 - 11766

Published: Oct. 19, 2020

Abstract. Sulfuric acid has been shown to be a key driver for new particle formation and subsequent growth in various environments, mainly due its low volatility. However, direct measurements of gas-phase sulfuric are oftentimes not available, the current proxies cannot predict, example, nighttime concentrations or result significant discrepancies with measured values. Here, we define sources sinks different environments derive physical proxy utilized locations during periods when it is measured. We used H2SO4 from four locations: Hyytiälä, Finland; Agia Marina, Cyprus; Budapest, Hungary; Beijing, China, representing semi-pristine boreal forest, rural environment Mediterranean area, urban heavily polluted megacity, respectively. The takes into account SO2 via OH oxidation other pathways, specifically stabilized Criegee intermediates. included condensation sink (CS) atmospheric clustering starting dimer formation. Indeed, found that observed concentration can explained by proposed similar coefficients contrasting where have tested it. Thus, more flexible an important improvement over previous proxies. Following recommendations this paper, specific location derived.

Language: Английский

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Formation and growth of sub-3 nm particles in megacities: impact of background aerosols

Faraday Discussions, Journal Year: 2020, Volume and Issue: 226, P. 348 - 363

Published: Aug. 4, 2020

In polluted urban environments, background aerosols govern the formation and growth of sub-3 nm particles.

Language: Английский

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Acid–Base Clusters during Atmospheric New Particle Formation in Urban Beijing

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(16), P. 10994 - 11005

Published: Aug. 2, 2021

Molecular clustering is the initial step of atmospheric new particle formation (NPF) that generates numerous secondary particles. Using two online mass spectrometers with and without a chemical ionization inlet, we characterized neutral clusters naturally charged ion during NPF periods in urban Beijing. In clusters, observed pure sulfuric acid (SA) SA-amine SA-ammonia (NH

Language: Английский

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The contribution of new particle formation and subsequent growth to haze formation

Environmental Science Atmospheres, Journal Year: 2022, Volume and Issue: 2(3), P. 352 - 361

Published: Jan. 1, 2022

We investigated the contribution of atmospheric new particle formation (NPF) and subsequent growth newly formed particles, characterized by high concentrations fine particulate matter (PM2.5). In addition to having adverse effects on visibility human health, these haze particles may act as cloud condensation nuclei, potentially large influences clouds precipitation. Using observations performed in 2019 Beijing, a polluted megacity China, we showed that variability rates (GR) originating from NPF depend only weakly low-volatile vapor - highly oxidated organic molecules (HOMs) sulphuric acid have no apparent connection with strength or level background pollution. then constrained aerosol dynamic model simulations observations. under conditions typical for Beijing atmosphere, is capable contributing more than 100 μg m-3 PM2.5 mass concentration simultaneously >103 cm-3 (diameter > nm) number concentration. Our reveal NPF, rate pre-existing population are all connected each other. Concerning PM pollution control, our results indicate reducing primary emissions might not result an effective enough decrease total until reduction precursor compounds imposed.

Language: Английский

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