Seasonal Characteristics of New Particle Formation and Growth in Urban Beijing

Environmental Science & Technology, Journal Year: 2020, Volume and Issue: 54(14), P. 8547 - 8557

Published: July 1, 2020

Understanding the atmospheric new particle formation (NPF) process within global range is important for revealing budget of aerosols and their impacts. We investigated seasonal characteristics NPF in urban environment Beijing. Aerosol size distributions down to ∼1 nm H2SO4 concentration were measured during 2018–2019. The observed rate 1.5 particles (J1.5) significantly higher than those clean environment, e.g., Hyytiälä, whereas growth not different. Both J1.5 frequency Beijing show a clear variation with maxima winter minima summer, while rates are generally same around year. that ambient temperature governing factor driving J1.5. In contrast, condensation sink daily maximum no significant periods. all four seasons, (H2SO4)n(amine)n clusters contributes sub-3 range, it less above 3 nm. Therefore, other species always needed larger particles.

Language: Английский

---

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

---

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

---

The driving factors of new particle formation and growth in the polluted boundary layer

Atmospheric chemistry and physics, Journal Year: 2021, Volume and Issue: 21(18), P. 14275 - 14291

Published: Sept. 27, 2021

Abstract. New particle formation (NPF) is a significant source of atmospheric particles, affecting climate and air quality. Understanding the mechanisms involved in urban aerosols important to develop effective mitigation strategies. However, NPF rates reported polluted boundary layer span more than 4 orders magnitude, reasons behind this variability are subject intense scientific debate. Multiple vapours have been postulated participate NPF, including sulfuric acid, ammonia, amines organics, but their relative roles remain unclear. We investigated CLOUD chamber using mixtures anthropogenic that simulate conditions. demonstrate environments largely driven by acid–base clusters, stabilized presence amines, high ammonia concentrations lower temperatures. Aromatic oxidation products, despite extremely low volatility, play minor role chosen environment can be for growth hence survival newly formed particles. Our measurements quantitatively account highly diverse explain its large observed variability. Such quantitative information obtained under controlled laboratory conditions will help interpretation future ambient observations atmospheres.

Language: Английский

---

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

---

Insufficient Condensable Organic Vapors Lead to Slow Growth of New Particles in an Urban Environment

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(14), P. 9936 - 9946

Published: June 24, 2022

Atmospheric new particle formation significantly affects global climate and air quality after newly formed particles grow above ∼50 nm. In polluted urban atmospheres with 1-3 orders of magnitude higher rates than those in clean atmospheres, growth are comparable or even lower for reasons that were previously unclear. Here, we address the slow Beijing advanced measurements size-resolved molecular composition nanoparticles using thermal desorption chemical ionization mass spectrometer gas precursors nitrate CI-APi-ToF. A model combining condensational particle-phase acid-base chemistry was developed to explore mechanisms. The 8-40 nm during events is dominated by organics (∼80%) sulfate (∼13%), remainder from base compounds, nitrate, chloride. With increase sizes, fraction decreases, while slow-desorbed organics, organic acids, increases. simulated consistent measured results most cases, they both indicate vapors H2SO4 major pathway reactions play a minor role. comparison high concentrations gaseous sulfuric acid amines cause rates, concentration condensable comparably under NOx levels, relatively high-volatility nitrogen-containing oxidation products higher. insufficient lead growth, which further causes low survival environments. Thus, some extent, counteract impact on

Language: Английский

---

The missing base molecules in atmospheric acid–base nucleation

National Science Review, Journal Year: 2022, Volume and Issue: 9(10)

Published: July 25, 2022

Transformation of low-volatility gaseous precursors to new particles affects aerosol number concentration, cloud formation and hence the climate. The clustering acid base molecules is a major mechanism driving fast nucleation initial growth in atmosphere. However, acid-base cluster composition, measured using state-of-the-art mass spectrometers, cannot explain high rate particles. Here we present strong evidence for existence such as amines smallest atmospheric sulfuric clusters prior their detection by spectrometers. We demonstrate that forming (H2SO4)1(amine)1 rate-limiting step H2SO4-amine uptake pathway H2SO4 clusters. proposed very consistent with particle urban Beijing, which dimethylamine key while other bases ammonia may contribute larger Our findings further underline fact amines, even at low concentrations when undetected clusters, can be crucial planetary boundary layer.

Language: Английский

---

Emissions of Ammonia and Other Nitrogen-Containing Volatile Organic Compounds from Motor Vehicles under Low-Speed Driving Conditions

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(9), P. 5440 - 5447

Published: April 11, 2022

Emissions of NH3 and nine nitrogen-containing volatile organic compounds (NVOCs) (C1–3-amines, C1–3-amides, C1–3-imines) from motor vehicles powered by gasoline, diesel, natural gas under low-speed driving conditions roadside in situ measurements were characterized using a water-cluster chemical ionization mass spectrometer trace monitors. The total emission strength diesel trucks was the greatest followed those gasoline cars cars. per vehicle found to be 2–3 orders magnitude greater than that all NVOCs, regardless type vehicle. Although much lower emissions amides or imines, amines sufficient produce atmospheric concentrations exceeding threshold level for enhance nucleation several magnitude. Different engine reduction technologies (e.g., three-way catalytic converter vs selective reduction) can lead different NVOC profiles. During lifetime vehicle, its most likely increase with mileage. Source profiles three types also obtained measurements. These valuable contribution air pollution management system terms source apportionment, elucidating contributions specific

Language: Английский

---

Significant contributions of trimethylamine to sulfuric acid nucleation in polluted environments

npj Climate and Atmospheric Science, Journal Year: 2023, Volume and Issue: 6(1)

Published: June 27, 2023

Abstract As one of the least understood aerosol processes, nucleation can be a dominant source atmospheric aerosols. Sulfuric acid (SA)-amine binary with dimethylamine (DMA) has been recognized as governing mechanism in polluted continental boundary layer. Here we demonstrate importance trimethylamine (TMA) for complex atmosphere and propose molecular-level SA-DMA-TMA ternary an improvement upon conventional mechanism. Using proposed mechanism, could connect gaseous amines to SA-amine cluster signals measured urban Beijing. Results show that TMA accelerate SA-DMA-based new particle formation Beijing by 50–100%. Considering global abundance DMA, our findings imply comparable DMA layer, probably higher contributions from rural environments future controlled emissions.

Language: Английский

---

Overlooked significance of iodic acid in new particle formation in the continental atmosphere

Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(31)

Published: July 24, 2024

New particle formation (NPF) substantially affects the global radiation balance and climate. Iodic acid (IA) is a key marine NPF driver that recently has also been detected inland. However, its impact on continental nucleation remains unclear. Here, we provide molecular-level evidence IA greatly facilitates clustering of two typical land-based nucleating precursors: dimethylamine (DMA) sulfuric (SA), thereby enhancing nucleation. Incorporating this mechanism into an atmospheric chemical transport model, show IA-induced enhancement could realize increase over 20% in SA–DMA rate iodine-rich regions China. With declining anthropogenic pollution driven by carbon neutrality clean air policies China, enhance rates 1.5 to 50 times 2060. Our results demonstrate overlooked role highlight necessity for considering synergistic SA-IA-DMA modeling correct representation climatic impacts aerosols.

Language: Английский

---