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

Proceedings of the National Academy of Sciences, Год журнала: 2024, Номер 121(31)

Опубликована: Июль 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.

Язык: Английский

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The striking effect of vertical mixing in the planetary boundary layer on new particle formation in the Yangtze River Delta

The Science of The Total Environment, Год журнала: 2022, Номер 829, С. 154607 - 154607

Опубликована: Март 17, 2022

Язык: Английский

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Global simulations of monoterpene-derived peroxy radical fates and the distributions of highly oxygenated organic molecules (HOMs) and accretion products

Atmospheric chemistry and physics, Год журнала: 2022, Номер 22(8), С. 5477 - 5494

Опубликована: Апрель 26, 2022

Abstract. We evaluate monoterpene-derived peroxy radical (MT-RO2) unimolecular autoxidation and self- cross-reactions with other RO2 species in the GEOS-Chem global chemical transport model. The formation of associated highly oxygenated organic molecules (HOMs) accretion products are tracked competition bimolecular reactions. Autoxidation is dominant fate up to 6–8 km for first-generation MT-RO2, which can undergo H shifts. Reaction NO be a more common H-shift rate constants < 0.1 s−1 or at altitudes higher than 8 due imposed Arrhenius temperature dependence For MT-derived HOM-RO2, generated by multistep reaction predicted major throughout most boreal tropical forest regions, whereas dominates temperate subtropical forests Northern Hemisphere. newly added reactions result an approximate 4 % average decrease HO2 RO2, mainly faster self-/cross-reactions but impact upon HO2, OH, NOx abundances only important planetary boundary layer (PBL) over portions forests. Predicted HOM concentrations MT-rich regions seasons exceed total aerosol standard version model depending on parameters used. Comparisons observations reveal that large uncertainties remain key processes, especially respect photochemical lifetime volatility HOMs as well rates branching products. Further laboratory studies related MT-RO2-derived gas-phase product kinetics – their atmospheric fate, such gas–particle partitioning, multiphase chemistry, net secondary needed.

Язык: Английский

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Atmospheric nanoparticle growth

Reviews of Modern Physics, Год журнала: 2023, Номер 95(4)

Опубликована: Ноя. 9, 2023

Atmospheric nanoparticles can serve as nuclei for cloud droplets, thereby inducing significant but uncertain effects on the radiative forcing of climate system. This article focuses physicochemical processes that govern growth these particles from formation molecular clusters until reach sizes where they act condensation nuclei. The review describes latest developments in measurement and modeling connects domains to large-scale simulations such Earth system models. authors recommend closer coordination among laboratory studies, atmospheric measurements, understand importance

Язык: Английский

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Role of Methanesulfonic Acid in Sulfuric Acid–Amine and Ammonia New Particle Formation

ACS Earth and Space Chemistry, Год журнала: 2023, Номер 7(3), С. 653 - 660

Опубликована: Март 7, 2023

Aerosol nucleation accounts for over half of all seed particles cloud droplet formation. In the atmosphere, sulfuric acid (SA) nucleates with ammonia, amines, oxidized organics, and many more compounds to form particles. Studies have also shown that methanesulfonic (MSA) independently amines ammonia. MSA SA are produced simultaneously via dimethyl sulfide oxidation in marine atmosphere. However, limited knowledge exists on how nucleate together presence various atmospherically relevant base compounds, which is critical predicting rates accurately. This work provides experimental evidence react SA-MSA-base has different reaction pathways than SA-base nucleation. Specifically, formation SA-MSA heterodimer creates energetically favorable SA-MSA-methylamine an enhancement rates. SA-trimethylamine suppressed by MSA, likely due steric hindrance trimethylamine. These results display importance including reactions between SA, predict particle

Язык: Английский

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Global Simulations of Phase State and Equilibration Time Scales of Secondary Organic Aerosols with GEOS-Chem

ACS Earth and Space Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Фев. 10, 2025

The phase state of secondary organic aerosols (SOA) can range from liquid through amorphous semisolid to glassy solid, which is important consider as it influences various multiphase processes including SOA formation and partitioning, chemistry, cloud activation. In this study, we simulate the glass transition temperature viscosity over globe using global chemical transport model, GEOS-Chem. simulated spatial distributions show that at surface exist equatorial regions oceans, in midlatitude continental regions, solid lands with low relative humidity. predicted viscosities are mostly consistent available measurements. free troposphere, particles be 850 hPa 500 hPa, except tropical Amazonia, where viscous. Phase also exhibits seasonal variation a higher frequency winter compared warmer seasons. We calculate equilibration time scales partitioning (τeq) effective mass accommodation coefficient (αeff), indicating τeq shorter than step GEOS-Chem 20 min αeff close unity for most locations level, supporting application equilibrium partitioning. However, prolonged lowered drylands upper suggesting kinetically limited growth would need considered these future large-scale model studies.

Язык: Английский

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Oxidized organic molecules in the tropical free troposphere over Amazonia

National Science Review, Год журнала: 2023, Номер 11(1)

Опубликована: Май 15, 2023

New particle formation (NPF) in the tropical free troposphere (FT) is a globally important source of cloud condensation nuclei, affecting properties and climate. Oxidized organic molecules (OOMs) produced from biogenic volatile compounds are believed to contribute aerosol FT, but without direct chemical observations. We performed situ molecular-level OOMs measurements at Bolivian station Chacaltaya 5240 m above sea level, on western edge Amazonia. For first time, we demonstrate presence OOMs, mainly with 4-5 carbon atoms, both gas-phase particle-phase (in terms mass contribution) FT air These observations, combined history analyses, indicate that observed linked isoprene emitted rainforests hundreds kilometers away. Based measurements, find these can NPF, least growth newly formed nanoparticles, continental scale. Thus, our study fundamental significant step understanding process FT.

Язык: Английский

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Look Up: Probing the Vertical Profile of New Particle Formation and Growth in the Planetary Boundary Layer With Models and Observations

Journal of Geophysical Research Atmospheres, Год журнала: 2023, Номер 128(3)

Опубликована: Янв. 20, 2023

Abstract The processes of new particle formation (NPF) and growth are important contributors to cloud condensation nuclei (CCN) concentrations, CCN for climate from their impact on planetary radiative forcing. While the general ubiquity importance NPF is understood, vertical extent governing mechanisms in lower troposphere uncertain. We present an analysis four events two non‐NPF during HI‐SCALE field campaign at Southern Great Plains observatory Oklahoma, USA. First, we analyzed airborne ground‐based observations aerosol gas‐phase properties. Second, used a column chemistry microphysics model probe factors that influence profile NPF. During HI‐SCALE, found several instances enhanced occurring hundred meters above surface; however, spatio‐temporal characteristics observed made comparisons between airborne‐ difficult. represented (or lack NPF) surface final diameters within 10 nm. predicted rates upper mixed layer, this enhancement primarily due temperature dependence schemes, but was also dependent precursors measured HI‐SCALE. mixing either or suppressed rates, number surface. Finally, our provides insights future campaigns modeling efforts investigating

Язык: Английский

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A dynamic parameterization of sulfuric acid–dimethylamine nucleation and its application in three-dimensional modeling

Atmospheric chemistry and physics, Год журнала: 2023, Номер 23(15), С. 8789 - 8804

Опубликована: Авг. 9, 2023

Abstract. Sulfuric acid (SA) is a governing gaseous precursor for atmospheric new particle formation (NPF), major source of global ultrafine particles, in environments studied around the world. In polluted urban atmospheres with high condensation sinks (CSs), stable SA–amine clusters, such as SA–dimethylamine (DMA) usually initializes intense NPF events. Coagulation scavenging and cluster evaporation are dominant sink processes clusters atmospheres, yet these loss not quantitatively included present parameterizations nucleation. We herein report parameterization SA–DMA nucleation, based on dynamic simulations quantum chemistry calculations, certain simplifications to greatly reduce computational costs. Compared previous nucleation parameterizations, this was able reproduce dependences rates temperature CSs. then incorporated it three-dimensional (3-D) chemical transport model simulate evolution number size distributions. Simulation results showed good consistency observations occurrence events distributions wintertime Beijing represented significant improvement compared that using without coagulation scavenging. Quantitative analysis shows contributes significantly aerosol population during 3-D (>99 % >60 %, respectively). These broaden understanding stress necessity including effects stability simulating simulations. Representing thus likely improve performance apportionment quantification air quality, human health, climate.

Язык: Английский

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Formation of highly oxygenated organic molecules from the oxidation of limonene by OH radical: significant contribution of H-abstraction pathway

Atmospheric chemistry and physics, Год журнала: 2023, Номер 23(13), С. 7297 - 7319

Опубликована: Июль 4, 2023

Abstract. Highly oxygenated organic molecules (HOMs) play a pivotal role in the formation of secondary aerosol (SOA). Therefore, distribution and yields HOMs are fundamental to understand their fate chemical evolution atmosphere, it is conducive ultimately assess impact SOA on air quality climate change. In this study, gas-phase formed from reaction limonene with OH radicals photooxidation were investigated SAPHIR (Simulation Atmospheric PHotochemistry large Reaction chamber), using time-of-flight ionization mass spectrometer nitrate reagent ion (NO3--CIMS). A number HOMs, including monomers (C9–10) dimers (C17–20), detected classified into various families. Both closed-shell products open-shell peroxy (RO2) identified under low NO (0.06–0.1 ppb) high conditions (17 ppb). C10 most abundant HOM account for over 80 % total HOMs. Closed-shell two radical family, C10H15Ox⚫ (x=6–15) C10H17Ox⚫ (x=6–15), respective termination reactions NO, RO2, HO2. While likely by addition C10H16, dominant initial step plus OH, C10H15Ox⚫, via H abstraction OH. related contributed 41 42 at demonstrating that H-abstraction pathways significant Combining theoretical kinetic calculations, structure–activity relationships (SARs), data literature, observed RO2 intensities, we proposed tentative mechanisms both pathways. We further estimated molar be 1.97-1.06+2.52 0.29-0.16+0.38 respectively. Our study highlights importance provides yield oxidation simulate formation.

Язык: Английский

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