Evaluation of Aeris mid-infrared absorption (MIRA), Picarro CRDS (cavity ring-down spectroscopy) G2307, and dinitrophenylhydrazine (DNPH)-based sampling for long-term formaldehyde monitoring efforts DOI Creative Commons
Asher P. Mouat,

Zelda A. Siegel,

Jennifer Kaiser

et al.

Atmospheric measurement techniques, Journal Year: 2024, Volume and Issue: 17(7), P. 1979 - 1994

Published: April 8, 2024

Abstract. Current formaldehyde (HCHO) measurement networks rely on the TO-11A offline chemical derivatization technique, which can be resource intensive and limited in temporal resolution. In this work, we evaluate field performance of three new commercial instruments for continuous situ monitoring: Picarro cavity ring-down spectroscopy G2307 gas concentration analyzer Aeris Technologies' mid-infrared absorption Pico Ultra analyzers. All require regular drift correction, is accomplished through instrument zeroing using dinitrophenylhydrazine (DNPH)-coated cartridges, Drierite, or molecular sieves, while heated Hopcalite failed to remove all incoming HCHO. We show that a modified precision estimate accounting results values 0.09, 0.20, 0.22 ppb at 20 min integration time G2307, Ultra, Pico, respectively. After applying standard addition dynamic dilution calibrations, agreed within 13 % were well correlated with each other (all r ≥ 0.90). HCHO observations resulted normalized mean bias −58 compared co-located measurements (r=0.62, slope = 0.38, int 0.07 HCHO). Using 6-month deployment period Atlanta metropolitan area, determined units have sufficient accuracy capture spatial gradient. find midday concentrations decreased by 22.3 since 1999 city's urban core, DNPH nearby Photochemical Assessment Monitoring Station (PAMS) site greater decrease 53 %.

Language: Английский

A better representation of volatile organic compound chemistry in WRF-Chem and its impact on ozone over Los Angeles DOI Creative Commons
Qindan Zhu, Rebecca H. Schwantes, Matthew M. Coggon

et al.

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(9), P. 5265 - 5286

Published: May 7, 2024

The declining trend in vehicle emissions has underscored the growing significance of Volatile Organic Compound (VOC) from Chemical Products (VCP). However, accurately representing VOC chemistry simplified chemical mechanisms remains challenging due to its complexity including speciation and reactivity. Previous studies have predominantly focused on VOCs fossil fuel sources, leading an underrepresentation VCP sources. We developed integrated mechanism, RACM2B-VCP, that is compatible with WRF-Chem aimed enhance representation chemistry, particularly within present urban environment. Evaluation against Air Quality System (AQS) network data demonstrates our model configured RACM2B-VCP reproduces both magnitude spatial variability O3 as well PM2.5 Los Angeles. Furthermore, evaluation comprehensive measurements precursors Reevaluating Chemistry Pollutants California (RECAP-CA) airborne campaign Southwest Urban NO x Experiment (SUNVEx) ground site mobile laboratory campaign, confirm model's accuracy NOx many highlight remaining biases. Although there exists underprediction total reactivity observed species, exhibits good agreement for markers emitted different sectors, biogenic, fuel, Through sensitivity analyses, we probe contributions O3. Our results reveal 52% 35% local enhancement MDA8 arise anthropogenic Significantly, over 50% this fraction either or attributed emissions. mechanism created, described, evaluated work ideally suited ozone right reasons environment where mobile, are all important contributors formation.

Language: Английский

Citations

12
Increasing Contributions of Temperature-Dependent Oxygenated Organic Aerosol to Summertime Particulate Matter in New York City DOI Creative Commons
Tori Hass‐Mitchell, Taekyu Joo, Mitchell Rogers

et al.

ACS ES&T Air, Journal Year: 2024, Volume and Issue: 1(2), P. 113 - 128

Published: Jan. 22, 2024

As part of the summer 2022 NYC-METS (New York City metropolitan Measurements Emissions and TransformationS) campaign ASCENT (Atmospheric Science Chemistry mEasurement NeTwork) observational network, speciated particulate matter was measured in real time Manhattan Queens, NY, with additional gas-phase measurements. Largely due to observed reductions inorganic sulfate aerosol components over 21st century, summertime composition NYC has become predominantly organic (80-83%). Organic source apportionment via positive matrix factorization showed that this is dominated by secondary production as oxygenated (OOA) factors comprised 73-76% OA. Primary factors, including cooking-related (COA) hydrocarbon-like (HOA) minor fractions OA, only 13-15% 10-11%, respectively. The two sites presented considerable spatiotemporal variations OA factor concentrations despite similar average PM

Language: Английский

Citations

11
Differentiated emissions and secondary organic aerosol formation potential of organic vapor from industrial coatings in China DOI

Chengrui Liang,

Boyang Feng,

Shuxiao Wang

et al.

Journal of Hazardous Materials, Journal Year: 2024, Volume and Issue: 466, P. 133668 - 133668

Published: Jan. 30, 2024

Language: Английский

Citations

11
Ozone in the Desert Southwest of the United States: A Synthesis of Past Work and Steps Ahead DOI
Armin Sorooshian, Avelino F. Arellano, Matthew P. Fraser

et al.

ACS ES&T Air, Journal Year: 2024, Volume and Issue: 1(2), P. 62 - 79

Published: Jan. 24, 2024

A region often neglected in the grander scale of general atmospheric chemistry studies and model evaluation for gas-phase is desert southwest U.S. Despite regulatory progress, challenges meeting National Ambient Air Quality Standard ozone motivate a re-examination unique meteorological conditions, interactions between desert, agricultural, built environmental landscapes, emissions across natural anthropogenic sources, regional transport precursors that govern formation Southwest. Arizona includes multiple nonattainment counties with situation terms its environment (e.g., vegetation, meteorology, fire prone areas), complex terrain, urban growth, vulnerability, limited knowledge base. Here we summarize past works investigating over Arizona, including 61 peer-reviewed publications found since first one 1996, determine significant gaps to guide future research aim improving policy. more in-depth focus placed here on Maricopa County, which Phoenix Metropolitan area, where population growth recent decades coupled extreme high temperatures surrounding terrain creates poorly understood airshed chemistry, thereby complicating decisions. We suggest paths forward, improved monitoring, assessment, modeling tools region, better leveraging archived data, engagement public, government, This Review highly relevant as well other semiarid arid regions, represent most common land type globally, warranting attention.

Language: Английский

Citations

10
Evaluation of Aeris mid-infrared absorption (MIRA), Picarro CRDS (cavity ring-down spectroscopy) G2307, and dinitrophenylhydrazine (DNPH)-based sampling for long-term formaldehyde monitoring efforts DOI Creative Commons
Asher P. Mouat,

Zelda A. Siegel,

Jennifer Kaiser

et al.

Atmospheric measurement techniques, Journal Year: 2024, Volume and Issue: 17(7), P. 1979 - 1994

Published: April 8, 2024

Abstract. Current formaldehyde (HCHO) measurement networks rely on the TO-11A offline chemical derivatization technique, which can be resource intensive and limited in temporal resolution. In this work, we evaluate field performance of three new commercial instruments for continuous situ monitoring: Picarro cavity ring-down spectroscopy G2307 gas concentration analyzer Aeris Technologies' mid-infrared absorption Pico Ultra analyzers. All require regular drift correction, is accomplished through instrument zeroing using dinitrophenylhydrazine (DNPH)-coated cartridges, Drierite, or molecular sieves, while heated Hopcalite failed to remove all incoming HCHO. We show that a modified precision estimate accounting results values 0.09, 0.20, 0.22 ppb at 20 min integration time G2307, Ultra, Pico, respectively. After applying standard addition dynamic dilution calibrations, agreed within 13 % were well correlated with each other (all r ≥ 0.90). HCHO observations resulted normalized mean bias −58 compared co-located measurements (r=0.62, slope = 0.38, int 0.07 HCHO). Using 6-month deployment period Atlanta metropolitan area, determined units have sufficient accuracy capture spatial gradient. find midday concentrations decreased by 22.3 since 1999 city's urban core, DNPH nearby Photochemical Assessment Monitoring Station (PAMS) site greater decrease 53 %.

Language: Английский

Citations

10