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

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New particle formation from isoprene under upper-tropospheric conditions

Nature, Journal Year: 2024, Volume and Issue: 636(8041), P. 115 - 123

Published: Dec. 4, 2024

Language: Английский

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Multiple eco-regions contribute to the seasonal cycle of Antarctic aerosol size distributions

Atmospheric chemistry and physics, Journal Year: 2025, Volume and Issue: 25(2), P. 1145 - 1162

Published: Jan. 28, 2025

Abstract. In order to reduce the uncertainty of aerosol radiative forcing in global climate models, we need better understand natural sources which are important constrain current and pre-industrial climate. Here, analyse particle number size distributions (PNSDs) collected during a year (2015) across four coastal inland Antarctic research bases (Halley, Marambio, Dome C King Sejong). We utilise k-means cluster analysis separate PNSD data into six main categories. “Nucleation” “bursting” PNSDs occur 28 %–48 % time between sites, most commonly at sites Marambio Sejong where air masses mostly come from west travel over extensive regions sea ice, marginal ice open ocean likely arise new formation. “Aitken high”, low” “bimodal” 37 %–68 time, on Plateau, atmospheric transport ageing originating both boundary layer free troposphere. “Pristine” with low concentrations 12 %–45 Halley, located altitudes far melting influenced by west. Not only spray primary aerosols gas secondary sources, but also different impacting stations should be kept mind when deliberating upon precursor stations. infer that components pelagic sympagic strongly contribute annual seasonal cycle aerosols. Our simultaneous measurements stress importance variation biogeochemistry region.

Language: Английский

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A cluster-of-functional-groups approach for studying organic enhanced atmospheric cluster formation

Aerosol Research, Journal Year: 2024, Volume and Issue: 2(1), P. 123 - 134

Published: June 4, 2024

Abstract. The role of organic compounds in atmospheric new particle formation is difficult to disentangle due the myriad potentially important oxygenated molecules (OOMs) present atmosphere. Using state-of-the-art quantum chemical methods, we here employ a novel approach, denoted “cluster-of-functional-groups” for studying involvement OOMs cluster formation. Instead usual “trial-and-error” approach testing ability experimentally identified form stable clusters with other nucleation precursors, study which, and how many, intermolecular interactions are required given OOM clusters. In this manner can reverse engineer elusive structure candidates that might be involved enhanced We calculated binding free energies all combinations donor acceptor functional groups investigate which most preferentially bind each precursors such as sulfuric acid bases (ammonia, methyl-, dimethyl- trimethylamine). find multiple carboxyl lead substantially more compared groups. Employing dynamics simulations, hypothetically composed stabilize acid–base provide recommendations potential multi-carboxylic tracer should explicitly studied future. presented generally applicable employed many applications, ion-induced elucidating structural patterns facilitate ice nucleation.

Language: Английский

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Role of Iodine-Assisted Aerosol Particle Formation in Antarctica

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(17), P. 7314 - 7324

Published: April 16, 2024

New particle formation via the ion-mediated sulfuric acid and ammonia molecular clustering mechanism remains most widely observed experimentally verified pathway. Recent laboratory level observations indicate iodine-driven nucleation as a potentially important source of new particles, especially in coastal areas. In this study, we assess role iodine species using best available thermochemistry data coupled to detailed 1-d column model which is run along air mass trajectories over Southern Ocean coast Antarctica. masses traversing open ocean, SA-NH

Language: Английский

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Direct Measurements of Covalently Bonded Sulfuric Anhydrides from Gas-Phase Reactions of SO₃ with Acids under Ambient Conditions

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(22), P. 15562 - 15575

Published: May 21, 2024

Sulfur trioxide (SO3) is an important oxide of sulfur and a key intermediate in the formation sulfuric acid (H2SO4, SA) Earth's atmosphere. This conversion to SA occurs rapidly due reaction SO3 with water dimer. However, gas-phase has been measured directly at concentrations that are comparable under polluted mega-city conditions, indicating gaps our current understanding sources fates SO3. Its atmospheric acids could be one such fate can have significant implications for chemistry. In present investigation, laboratory experiments were conducted flow reactor generate range previously uncharacterized condensable sulfur-containing products by reacting set atmospherically relevant inorganic organic room temperature pressure. Specifically, known responsible most ambient new particle events, iodic (HIO3, IA) SA, observed react promptly form anhydride (IO3SO3H, ISA) disulfuric (H2S2O7, DSA). Carboxylic anhydrides (CSAs) C2 C3 monocarboxylic (acetic propanoic acid) dicarboxylic (oxalic malonic acid)–carboxylic acids. The formed detected nitrate-ion-based chemical ionization pressure interface time-of-flight mass spectrometer (NO3–-CI-APi-TOF; NO3–-CIMS). Quantum methods used compute rate coefficients, probe mechanisms, model chemistry inherent detection NO3–-CIMS. Additionally, we use NO3–-CIMS data report its polluted, marine polar, volcanic plume conditions. Considering these regions rich precursors studied here, reported reactions need accounted modeling formation.

Language: Английский

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Distinguishing Surface and Bulk Reactivity: Concentration-Dependent Kinetics of Iodide Oxidation by Ozone in Microdroplets

The Journal of Physical Chemistry A, Journal Year: 2024, Volume and Issue: 128(41), P. 8970 - 8982

Published: Oct. 3, 2024

Iodine oxidation reactions play an important role in environmental, biological, and industrial contexts.The multiphase reaction between aqueous iodide ozone is of particular interest due to its prevalence the marine atmosphere unique reactivity at air-water interface.Here, we explore concentration dependence I -+ O3 levitated microdroplets under both acidic basic conditions.To interpret experimental kinetics, molecular simulations are used benchmark a kinetic model, which enables insight into interface, nanometer-scale sub-surface region, bulk interior droplet.For all experiments, description gas-and liquid-phase diffusion critical interpreting results.We find that surface dominates kinetics concentrated conditions, with reactive uptake coefficient approaching upper limit 10 -2 pH 3. In contrast, dominate more dilute alkaline inhibition 12 10x smaller.The origin changing mechanism explored compared previous ozonedependent measurements.

Language: Английский

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Iodide, iodate & dissolved organic iodine in the temperate coastal ocean

Frontiers in Marine Science, Journal Year: 2024, Volume and Issue: 11

Published: Feb. 21, 2024

The surface ocean is the main source of iodine to atmosphere, where it plays a crucial role including in catalytic removal tropospheric ozone. availability oceanic governed by its biogeochemical cycling, controls which are poorly constrained. Here we show near two-year time series primary species, iodide, iodate and dissolved organic (DOI) inner shelf marine waters Western English Channel (UK). median ± standard deviation concentrations between November 2019 September 2021 (n=76) were: iodide 88 17 nM (range 61-149 nM), 293 28 (198-382 DOI 16 (<0.12-75 nM) total (dI T ) 399 30 (314-477 nM). Though lower than inorganic ion concentrations, was persistent non-negligible component dI , consistent with previous studies coastal waters. Over series, not conserved missing pool accounted for ~6% observed concentration suggesting complex mechanisms governing renewal. contribution excess ( I* sourced from margin towards generally low (3 29 but exceptional events influenced up ±100 nM. seasonal variability speciation asynchronous phytoplankton productivity. Nevertheless, reduction began as light levels then biomass increased spring attained peak mid late autumn during post-bloom conditions. Dissolved present, variable, throughout year. During winter, due advection North Atlantic timing changes magnitude subsumed seawater processes supports paradigm that transformations species biologically mediated, though directly linked.

Language: Английский

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Temperature, humidity, and ionisation effect of iodine oxoacid nucleation

Environmental Science Atmospheres, Journal Year: 2024, Volume and Issue: 4(5), P. 531 - 546

Published: Jan. 1, 2024

Raising the ionisation rate (IR) increases ion concentration, but also amplifies losses due to ion–ion recombination, consequently diminishing formation of charged clusters at low HIO 3 concentrations.

Language: Английский

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Pan-Arctic methanesulfonic acid aerosol: source regions, atmospheric drivers, and future projections

npj Climate and Atmospheric Science, Journal Year: 2024, Volume and Issue: 7(1)

Published: July 13, 2024

Abstract Natural aerosols are an important, yet understudied, part of the Arctic climate system. marine biogenic aerosol components (e.g., methanesulfonic acid, MSA) becoming increasingly important due to changing environmental conditions. In this study, we combine in situ observations with atmospheric transport modeling and meteorological reanalysis data a data-driven framework aim (1) identify seasonal cycles source regions MSA, (2) elucidate relationships between MSA variables, (3) project response based on trends extrapolated from variables determine which contributing these projected changes. We have identified main areas be Atlantic Pacific sectors Arctic. Using gradient-boosted trees, were able explain 84% variance find that most for indirectly related either gas- or aqueous-phase oxidation dimethyl sulfide (DMS): shortwave longwave downwelling radiation, temperature, low cloud cover. undergo shift, non-monotonic decreases April/May increases June-September, over next 50 years. Different different months driving changes, highlighting complexity influences natural component. Although oceanic (sea surface DMS emissions, sea ice) precipitation remains seen, here show will likely shift solely changes variables.

Language: Английский

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