Source and Chemistry of Hydroxymethanesulfonate (HMS) in Fairbanks, Alaska

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(12), P. 7657 - 7667

Published: May 11, 2022

Fairbanks, Alaska, is a subarctic city with fine particle (PM2.5) concentrations that exceed air quality regulations in winter due to weak dispersion caused by strong atmospheric inversions, local emissions, and the unique chemistry occurring under cold dark conditions. Here, we report on observations from winters of 2020 2021, motivated our pilot study showed exceptionally high hydroxymethanesulfonate (HMS) or related sulfur(IV) species (e.g., sulfite bisulfite). We deployed online particle-into-liquid sampler-ion chromatography (PILS-IC) conjunction suite instruments determine HMS precursors (HCHO, SO2) aerosol composition general, goal characterize sources sinks wintertime Fairbanks. PM2.5 comprised significant fraction sulfur (26-41%) overall mass concentration 2.8-6.8% during pollution episodes, substantially higher than what has been observed other regions, likely low temperatures. peaked January, lower December February, resulting changes meteorological Strong correlations inorganic sulfate organic events suggest linked processes responsible for poor episodes. These findings demonstrate aspects formation humid atmospheres.

Language: Английский

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Secondary aerosol formation during the dark oxidation of residential biomass burning emissions

Environmental Science Atmospheres, Journal Year: 2022, Volume and Issue: 2(5), P. 1221 - 1236

Published: Jan. 1, 2022

Particulate matter from biomass burning emissions affects air quality, ecosystems and climate; however, quantifying these effects requires that the connection between primary secondary aerosol production is firmly established. We performed atmospheric simulation chamber experiments on chemical oxidation of residential under dark conditions. Biomass organic was found to age conditions, with its oxygen-to-carbon ratio increasing by 7-34% producing 1-38 μg m-3 (5-80% increase over fresh aerosol) after 30 min exposure NO3 radicals in (corresponding 1-3 h typical nighttime radical concentrations an urban environment). The average mass concentration SOA formed dark-oxidation conditions comparable 3 (equivalent 7-10 ambient exposure) ultraviolet lights (6 or a 47% emitted concentration). dark-aging showed substantial nitrate (0.12-3.8 m-3), 46-100% which form nitrates. pH remained practically constant at 2.8 throughout experiment. This value promotes inorganic partitioning particulate phase, potentially contributing buildup boundary layer enhancing long-range transport. These results suggest through reactions additional formation pathway emission plumes should be accounted for chemical-transport models.

Language: Английский

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HETerogeneous vectorized or Parallel (HETPv1.0): an updated inorganic heterogeneous chemistry solver for the metastable-state NH₄⁺–Na⁺–Ca²⁺–K⁺–Mg²⁺–SO₄²⁻–NO₃⁻–Cl⁻–H₂O system based on ISORROPIA II

Geoscientific model development, Journal Year: 2024, Volume and Issue: 17(6), P. 2197 - 2219

Published: March 19, 2024

Abstract. We describe a new Fortran computer program to solve the system of equations for NH4+–Na+–Ca2+–K+–Mg2+–SO42-–NO3-–Cl−–H2O system, based on algorithms ISORROPIA II. Specifically, code solves describing “forward” (gas + aerosol input) metastable state but with algorithm improvements and corrections. These changes allow deliver more accurate solution results in formal evaluations accuracy roots systems equations, while reducing processing time practical applications by about 50 %. The improved performance from several implementation relative original algorithms. include (i) use “interpolate, truncate project” (ITP) root-finding approach rather than bisection, (ii) allowance search interval endpoints as valid at onset search, (iii) method polynomial subsystems (iv) elimination negative concentrations during iterative solutions, (v) corrections mass conservation enforcement, (vi) structure improvements. may be run either “vectorization” mode wherein global convergence criterion is used across multiple tests within same chemical subspace or “by case-by-case” individual test cases are solved criteria. latter was found efficient compiler tested here, users recommended both options their own systems. has been constructed explicitly conserve input all species considered solver provided open-source shareware.

Language: Английский

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Enhanced aqueous formation and neutralization of fine atmospheric particles driven by extreme cold

Science Advances, Journal Year: 2024, Volume and Issue: 10(36)

Published: Sept. 4, 2024

The prevailing view for aqueous secondary aerosol formation is that it occurs in clouds and fogs, owing to the large liquid water content compared minute levels fine particles. Our research indicates this may need reevaluation due enhancements reactions highly concentrated small Here, we show low temperature can play a role through unique effect on particle pH substantially modulate formation. Marked increases hydroxymethanesulfonate observed under extreme cold Fairbanks, Alaska, demonstrate effect. These findings provide insight chemistry particles conditions expanding possible regions of are dependent beyond high water.

Language: Английский

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Impact of mineral dust on the global nitrate aerosol direct and indirect radiative effect

Atmospheric chemistry and physics, Journal Year: 2025, Volume and Issue: 25(2), P. 1333 - 1351

Published: Jan. 31, 2025

Abstract. Nitrate (NO3-) aerosol is projected to increase dramatically in the coming decades and may become dominant inorganic particle species. This due continued strong decrease SO2 emissions, which not accompanied by a corresponding NOx especially NH3 emissions. Thus, radiative effect (RE) of NO3- more important than that SO42- future. The physicochemical interactions mineral dust particles with gas tracers play an role influencing overall RE non-dust aerosols but can be major source uncertainty their lack representation many global climate models. Therefore, this study investigates how what extent affects current through both radiation (REari) cloud (REaci) at top atmosphere (TOA). For purpose, multiyear simulations nudged towards observed atmospheric circulation were performed chemistry model EMAC, while thermodynamics between simulated thermodynamic equilibrium ISORROPIA-lite. emission flux cations Na+, Ca2+, K+, Mg2+ calculated as fraction total aeolian based on unique chemical composition deserts worldwide. Our results reveal positive negative shortwave longwave effects different regions world via aerosol–radiation adjustments. Overall, direct contributes cooling −0.11 W m−2, driven fine-mode short wavelengths. Regarding indirect effect, it noteworthy exerts mean warming +0.17 m−2. While presence enhances ability act condensation nuclei (CCN), simultaneously inhibits formation droplets from smaller anthropogenic particles. coagulation fine CCN larger nitrate-coated particles, leads reduction number concentration. mechanism reduced albedo thus attributed warming.

Language: Английский

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Capturing the Relative‐Humidity‐Sensitive Gas–Particle Partitioning of Organic Aerosols in a 2D Volatility Basis Set

Geophysical Research Letters, Journal Year: 2024, Volume and Issue: 51(3)

Published: Feb. 4, 2024

Abstract Aerosol water affects the physicochemical properties and mass concentration of organic aerosols (OA), but it is typically omitted by air quality, weather, climate models. We compare two classes simplified models to estimate OA uptake gas–particle partitioning compounds. One class uses a single‐hygroscopicity‐parameter ( κ ) approach while other based on reduced‐complexity Binary Activity Thermodynamics (BAT) model. show that BAT‐based two‐dimensional volatility basis set (VBS) model always predicts higher at elevated relative humidity (RH), for example, ∼16% 80% RH, than any variation ‐based method considered—even when BAT‐VBS lower uptake. The main reason being captures variations in effective saturation organics C *) with feature VBS methods lack. framework offers an efficient, RH‐sensitive treatment modeling.

Language: Английский

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Implementation of the ISORROPIA-lite aerosol thermodynamics model into the EMAC chemistry climate model (based on MESSy v2.55): implications for aerosol composition and acidity

Geoscientific model development, Journal Year: 2024, Volume and Issue: 17(3), P. 1111 - 1131

Published: Feb. 12, 2024

Abstract. This study explores the differences in performance and results by various versions of ISORROPIA thermodynamic module implemented within ECHAM/MESSy Atmospheric Chemistry (EMAC) model. Three different were used, II v1, v2.3, ISORROPIA-lite. First, v2.3 replaced v1 EMAC to improve pH predictions close neutral conditions. The newly developed ISORROPIA-lite has been added alongside v2.3. is more computationally efficient assumes that atmospheric aerosols exist always as supersaturated aqueous (metastable) solutions, while includes option allow for formation solid salts at low RH conditions (stable state). employing all three aerosol models compared each other evaluated against surface measurements from regional observational networks polluted Northern Hemisphere (Interagency Monitoring Protected Visual Environments (IMPROVE), European Evaluation Programme (EMEP), Acid Deposition Network East Asia (EANET)). between minimal comparisons with normalized mean absolute difference concentrations major components being less than 11 % even when phase state assumptions used. most notable lower predicted regions relative humidity range 20 60 stable mode. comparison observations yielded satisfactory agreement especially over USA Europe but higher deviations Asia, where overprediction nitrate was high 4 µg m−3 (∼20 %). annual on average a unit mode, mainly coarse-mode Middle East. use accelerated nearly 5 if calculations consume relatively small fraction computational time. can therefore be reliable alternative previous EMAC.

Language: Английский

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Seasonal Changes in the Oxidative Potential of Urban Air Pollutants: The Influence of Emission Sources and Proton- and Ligand-Mediated Dissolution of Transition Metals

ACS ES&T Air, Journal Year: 2024, Volume and Issue: 1(10), P. 1262 - 1275

Published: Aug. 29, 2024

The inhalation of fine particulate matter (PM

Language: Английский

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Characterization and dark oxidation of the emissions of a pellet stove

Environmental Science Atmospheres, Journal Year: 2023, Volume and Issue: 3(9), P. 1319 - 1334

Published: Jan. 1, 2023

Pellet combustion in residential heating stoves has increased globally during the last decade. Despite their high efficiency, widespread use of pellet is expected to adversely impact air quality. The atmospheric aging emissions received even less attention, focusing mainly on daytime conditions, while degree which undergo night-time as well role relative humidity remain poorly understood. In this study, environmental simulation chamber experiments were performed characterize fresh and aged organic aerosol (OA) emitted by a stove. stove PM1 (particulate matter with an aerodynamic diameter than 1 μm) consisted OA (93 ± 4%, mean standard deviation) black carbon (5 3%). primary (POA) oxygen-to-carbon ratio (O : C) was 0.58 0.04, higher that logwood emissions. at concentration 70 μg m-3 (after dilution equilibration chamber) semi-volatile (68%), low extremely volatility (16%) intermediate-volatility compounds. oxidation under dark conditions investigated injecting nitrogen dioxide (NO2) ozone (O3) into chamber, different (10-80%) (RH) levels. all secondary (SOA) formation observed, increasing levels after few hours exposure NO3 radicals. change composition extent depended RH. For RH, SOA mass formed up 30% initial OA, accompanied moderate both O C (7-8% increase) spectrum. Aging RH (60-80%) led more oxygenated (increase 11-18%), but only minor (1-10%) increase mass. indicates importance heterogeneous aqueous reactions system, oxidize original relatively small net These results show can chemically evolve photochemical activity (e.g. wintertime period) important enhancement certain conditions.

Language: Английский

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Recent improvements and maximum covariance analysis of aerosol and cloud properties in the EC-Earth3-AerChem model

Published: April 15, 2024

Abstract. Given the importance of aerosols, clouds and their interactions in climate system, it is imperative that global Earth system models accurately represent processes associated with them. This an important prerequisite if we were to narrow uncertainties future projections. In practice, this means continuous model evaluations improvements grounded observations are necessary. Numerous studies last few decades have shown both usability limitations utilizing satellite-based understanding evaluating aerosol-cloud interactions, particularly under varying meteorological satellite sensor sensitivity paradigms. Furthermore, vast range spatio-temporal scales at which aerosol cloud occur adds another dimension challenges while models. context, aim study two-fold. 1) We evaluate most recent, significant changes representation implemented EC-Earth3-AerChem framework EU project FORCeS compared its previous CMIP6 version. focus on physical properties radiative effects, wherever possible, using a simulator. report overall model. particular, strong warm bias chronically seen over Southern Ocean reduced significantly. 2) A statistical, maximum covariance analysis carried out between optical depth (AOD) droplet (CD) effective radius based recent EC-Earth3-AerChem/FORCeS simulation understand what extent Twomey effect can manifest itself larger scales. three oceanic low-level regimes due net cooling where pollution outflow from nearby continent simultaneously pervasive. statistical covariability AOD CD indeed dominantly visible even scale when amount composition favourably preconditioned for allowing interactions. Despite covariability, our shows cooling/warming shortwave effects top atmosphere regions increase/decrease radius. And be attributed low fraction, line observational studies.

Language: Английский

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