Modeling atmospheric brown carbon in the GISS ModelE Earth system model

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(10), P. 6275 - 6304

Published: May 29, 2024

Abstract. Brown carbon (BrC) is an absorbing organic aerosol (OA), primarily emitted through biomass burning (BB), which exhibits light absorption unique to both black (BC) and other aerosols. Despite many field laboratory studies seeking constrain BrC properties, the radiative forcing (RF) of still highly uncertain. To better understand its climate impact, we introduced One-Moment Aerosol (OMA) module GISS ModelE Earth system model (ESM). We assessed sensitivity primary processed a novel chemical aging scheme secondary formed from biogenic volatile compounds (BVOCs). Initial results show that typically contributes top-of-the-atmosphere (TOA) effect 0.04 W m−2. Sensitivity tests indicate explicitly simulating (separating it OAs), including BrC, bleaching contribute distinguishable effects should be accounted for in schemes. This addition prognostic allows greater physical complexity OA representation with no apparent trade-off performance, as evaluation optical depth against Robotic Network (AERONET) Moderate Resolution Imaging Spectroradiometer (MODIS) retrieval data, without scheme, reveals similar skill cases. Thus, simulated allow more physically based composition, crucial detailed like comparisons situ measurement campaigns. include summary best practices within at end this paper.

Language: Английский

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Satellite-based analysis of top of atmosphere shortwave radiative forcing trend induced by biomass burning aerosols over South-Eastern Atlantic

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

Published: June 12, 2024

Abstract This study investigates long-term changes in the shortwave direct aerosol radiative effect (DARE) at top of atmosphere (TOA) induced by biomass burning (BBA) transported from southern Africa to south-eastern Atlantic (SEA) stratocumulus region during extended fire seasons. The evolution since 2002 aerosol, cloud properties, and TOA outgoing radiation advanced passive satellite sensors are presented, as well observational trend clear-sky DARE clr retrieval all-sky all . Supplemented chemical transport model simulations, we estimate that has become more negative (−0.09 ± 0.06 W m −2 yr −1 ) due increased presence SEA. Meanwhile, positive ( + 0.04 0.15 aerosols cloudy sky regions. reveals capabilities capturing complex BBA-cloud-solar interactions for accurate forcing estimates projections.

Language: Английский

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Physicochemical Characterization of the Particulate Matter in New Jersey/New York City Area, Resulting from the Canadian Quebec Wildfires in June 2023

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(33), P. 14753 - 14763

Published: July 10, 2024

The global increase in wildfires, primarily driven by climate change, significantly affects air quality and health. Wildfire-emitted particulate matter (WFPM) is linked to adverse health effects, yet the toxicological mechanisms are not fully understood given its physicochemical complexity lack of spatiotemporal exposure data. This study focuses on characterization WFPM from a Canadian wildfire June 2023, which affected over 100 million people US Northeast, particularly around New Jersey/New York. Aerosol systems were deployed characterize during 3 day event, revealing unprecedented mass concentrations mainly

Language: Английский

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Tropospheric aerosols over the western North Atlantic Ocean during the winter and summer deployments of ACTIVATE 2020: life cycle, transport, and distribution

Atmospheric chemistry and physics, Journal Year: 2025, Volume and Issue: 25(4), P. 2087 - 2121

Published: Feb. 19, 2025

Abstract. The Aerosol Cloud meTeorology Interactions oVer the western ATlantic Experiment (ACTIVATE) is a NASA mission to characterize aerosol–cloud interactions over North Atlantic Ocean (WNAO). Such characterization requires understanding of life cycle, composition, transport pathways, and distribution aerosols WNAO. This study uses GEOS-Chem model simulate aerosol distributions properties that are evaluated against aircraft, ground-based, satellite observations during winter summer field deployments in 2020 ACTIVATE. Transport boundary layer (BL) behind cold fronts was major mechanism for American continental outflow pollution WNAO winter. Turbulent mixing main driver upward sea salt within ventilation out BL composition dominated by salt, which increased summer, followed organics sulfate. Aircraft situ measurements provided useful constraints on wet scavenging GEOS-Chem. generally captured observed features such as outflow, land–ocean gradient, anthropogenic with salt. Model sensitivity experiments elevated smoke injection heights mid-troposphere (versus BL) better reproduced from US wildfires summer. analysis suggests strong hygroscopic growth particles their seeding marine clouds (< 35° N). Future modeling efforts should focus improving parameterizations scavenging, implementing realistic heights, applying high-resolution models resolve vertical transport.

Language: Английский

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Radiative cooling in New York/New Jersey metropolitan areas by wildfire particulate matter emitted from the Canadian wildfires of 2023

Communications Earth & Environment, Journal Year: 2025, Volume and Issue: 6(1)

Published: April 21, 2025

Wildfire particulate matter from Canadian forest fires significantly impacted the air quality in northeastern United States during summer of 2023. Here, we used real-time and time-integrated instrumentation to characterize physicochemical properties radiative effects wildfire reaching metropolitan areas New Jersey/ York this extreme incident. The forcing -352.4 W/m2 derived here based on measured optical explains, some extent, ground level temperature reduction about 3 °C observed City Such negative densely populated megacities may limit natural ventilation, increase residence time background pollutants, exacerbating public health risks. This study highlights importance their potential implications for climate, health.

Language: Английский

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Accurate Measurement of the Optical Properties of Single Aerosol Particles Using Cavity Ring-Down Spectroscopy

The Journal of Physical Chemistry A, Journal Year: 2022, Volume and Issue: 126(17), P. 2619 - 2631

Published: April 25, 2022

New approaches for the sensitive and accurate quantification of aerosol optical properties are needed to improve current understanding unique physical chemistry airborne particles explore their roles in fields as diverse chemical manufacturing, healthcare, atmospheric science. We have pioneered use cavity ring-down spectroscopy (CRDS), with concurrent angularly resolved elastic light scattering measurements, interrogate single levitated electrodynamic traps. This approach enables robust such extinction cross sections individual known size. Our measurements can now distinguish absorption contributions overall extinction, from which real imaginary components complex refractive indices be retrieved linked composition. In this Feature Article, we show that innovative measurement platform precise spherical nonspherical particles, whether nonabsorbing or absorbing at CRDS probe wavelength. discuss limitations our key challenges addressed by controlled environments.

Language: Английский

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Nitration of Phenols by Reaction with Aqueous Nitrite: A Pathway for the Formation of Atmospheric Brown Carbon

ACS Earth and Space Chemistry, Journal Year: 2023, Volume and Issue: 7(3), P. 632 - 641

Published: Feb. 24, 2023

Nitrophenols are a major component of light-absorbing atmospheric organic aerosols, commonly referred to as brown carbon (BrC). Most nitrophenol formation pathways involve reactions phenolic compounds with OH, NO3, and NO2 in the gas phase. In this study, an aqueous production pathway is investigated that can proceed dark without apparent OH radical formation. Using high-performance liquid chromatography–mass spectrometry, we demonstrate catechol reacts acidic solutions dissolved nitrite form nitrocatechol. The rate nitration increases significantly from pH 4.4 3.4 such nitrocatechol susceptible second-generation under most conditions producing chromophores absorb visible region (peak at 425 nm). Increases N:C ratio reaction solution, detected by aerosol mass enhanced absorption 300 500 nm wood peat smoke extracts exposed suggest general pathway. which BrC process may occur discussed.

Language: Английский

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An attribution of the low single-scattering albedo of biomass burning aerosol over the southeastern Atlantic

Atmospheric chemistry and physics, Journal Year: 2023, Volume and Issue: 23(8), P. 4775 - 4799

Published: April 24, 2023

Abstract. Aerosol over the remote southeastern Atlantic is some of most sunlight-absorbing aerosol on planet: in situ free-tropospheric single-scattering albedo at 530 nm wavelength (SSA530 nm) ranges from 0.83 to 0.89 within ORACLES (ObseRvations Aerosols above CLouds and their intEractionS) aircraft flights late August–September. Here we seek explain low SSA. The SSA depends strongly black carbon (BC) number fraction, which 0.15 0.4. Low organic (OA)-to-BC mass ratios 8–14 modified combustion efficiency values >0.975 point indirectly dry, flame-efficient primarily grass fuels, with back trajectories ending miombo woodlands Angola. youngest aerosol, aged 4–5 d since emission, occupied top half a 5 km thick plume sampled directly west Angola vertically consistent BC:ΔCO (carbon monoxide) ratio, indicating homogenization source emissions. younger transported more quickly off continent by stronger winds, overlaid older, slower-moving larger mean particle size fraction BC-containing particles. This ongoing gas condensation coagulation smaller non-BC particles upon volumes OA:BC older were smaller, attributed evaporation following fragmentation, instead dilution or thermodynamics. CLARIFY (CLoud–Aerosol–Radiation Interaction Forcing: Year 2017) campaign aerosols that had traveled further reach Ascension Island. reported higher BC fractions, lower ratios, yet absorption coefficients compared this study's. Values one 2017 flight, held midway Island, are intermediate, confirming long-range changes. Overall data continuing oxidation through fragmentation releasing subsequently enter phase, reducing OA mass, rather than support best fit: SSA530nm=0.801+0055⋅(OA:BC) (r=0.84). fires southern Africa emit approximately one-third world's carbon; emitted distinct other regional smoke emissions, composition needs be represented appropriately realistically depict radiative effects.

Language: Английский

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Burning conditions and transportation pathways determine biomass-burning aerosol properties in the Ascension Island marine boundary layer

Atmospheric chemistry and physics, Journal Year: 2025, Volume and Issue: 25(4), P. 2333 - 2363

Published: Feb. 21, 2025

Abstract. African biomass-burning aerosol (BBA) in the southeast Atlantic Ocean (SEA) marine boundary layer (MBL) is an important contributor to Earth's radiation budget, yet its representation remains poorly constrained regional and global climate models. Data from Layered Smoke Interactions with Clouds (LASIC) field campaign on Ascension Island (7.95° S, 14.36° W) provide insight into how burning conditions, fuel type, transport pathways, atmospheric processing affect chemical, microphysical, optical properties of BBA between June September 2017. A total 10 individual plume events characterize seasonal evolution properties. Early-season inefficient fires, determined by low refractory black carbon above-background monoxide mixing ratios (rBC : ΔCO), led enhanced concentrations organic- sulfate-rich aerosols. Mid-season efficient higher rBC ΔCO values, rBC-enriched BBA. mix fires later season resulted conflicting Prolonged (∼ d) through MBL lower free troposphere (FT) facilitated chemical aqueous-phase processing, which a reduction organic mass concentrations. This (OA) (OA rBC) (2–5) compared values (5–15) nearby FT. These cloud oxidation processes yield more light-absorbing explain notably single-scattering albedo at 530 nm (SSA530) (< 0.80) observed MBL. study establishes robust correlation SSA530 OA across FT, underscoring dependency composition.

Language: Английский

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Assessment of light absorbing carbonaceous aerosol and its absorption properties from forest fire in Himalayan Critical Zone Observatory

The Science of The Total Environment, Journal Year: 2025, Volume and Issue: 968, P. 178878 - 178878

Published: Feb. 22, 2025

Language: Английский

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