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Grantee Research Project Results

Final Report: Improved Prediction of the Vertical Profile of Atmospheric Black Carbon: Development and Evaluation of WRF-CMAQ

EPA Grant Number: R835041
Title: Improved Prediction of the Vertical Profile of Atmospheric Black Carbon: Development and Evaluation of WRF-CMAQ
Investigators: Carlton, Annmarie
Institution: Rutgers
EPA Project Officer: Chung, Serena
Project Period: September 1, 2011 through August 31, 2014 (Extended to February 29, 2016)
Project Amount: $449,916
RFA: Black Carbon's Role In Global To Local Scale Climate And Air Quality (2010) RFA Text |  Recipients Lists
Research Category: Climate Change , Air

Objective:

To improve the model predictions of the vertical profile of particulate carbon through better representation of condensed phase organic chemistry in the three-dimensional photochemical model "CMAQ." The specific individual objectives were to: (1) develop condensed chemical and/or meteorological mechanisms suitable for inclusion in three-dimensional photochemical transport models (CTMs), to simulate cloud production of particulate “brown” carbon (BCcld) from a variety of organic precursors; (2) identify conditions and precursors that have the largest impact on BCcld for climate (e.g., those for which the vertical distribution is the most sensitive) and for air quality, conduct CMAQ simulations for the continental United States using different emissions to simulate a variety of control strategies to estimate the controllable fraction of BCcld and assign relative importance to individual source sectors; and (3) incorporate findings into the coupled Weather Research Forecasting-Community Multiscale Air Quality (WRF-CMAQ) model to be released to the public.

Summary/Accomplishments (Outputs/Outcomes):

Objective 1

In addition to testing and implementing new and expanded organic chemical mechanisms in the aqchem.F subroutine of CMAQ, we have developed chemical mechanisms for aerosol liquid water (ALW). Specfically, we have modeled uptake of glyoxal and methylglyoxal, ubiquitous water-soluble organic gases (WSOGs), to ALW to form optically active secondary organic aerosol (SOA). Laboratory-derived Setschenow coefficients were applied in CMAQ simulations of the continental United States during the Southern Oxidant and Aerosol Study (SOAS) to investigate SOA potential of common glyoxal, methylglyoxal and IEPOX gases as a function of aerosol molality. EPA regulations focused on SO2 and NOx can impact aerosol molality, and our Setschenow parameterization induces model sensitivity and response not previously present but observed in ambient data (i.e., statistically significant correlations between inorganic aerosol mass of sulfate and secondary organic aerosol mass). Our work suggests glyoxal’s potential SOA is enhanced by aerosol molality or “salting-in,” while IEPOX and methylglyoxal’s are reduced due to “salting out.” Nonetheless, IEPOX is expected to remain a dominant contributor, 50-90%, to potential SOA mass due to water-mediated chemistry in ALW.

Objective 2

Focusing on controllable anthropogenic emissions, we find that emissions from electric generation units (EGUs) impact ambient black carbon mass concentrations to a large degree both at the surface and aloft. At 800 mb, where the radiative impacts of particles are large because scattering is altitude dependent, black carbon mass concentrations can increase up to > 300% (mass basis) when the temporal profile of black carbon emissions from EGUs are more accurately described in CMAQ model simulations. Further, we find that in the Southeast United States particle phase liquid water mass concentrations have been decreasing, largely a consequence of sulfate reductions. These reductions are linked to and provide a plausible mechanistic explanation for recently noted observed decreases in optically active particulate organic carbon in the Southeast United States.

Objective 3

An extendable aqueous phase chemistry option (AQCHEM-KMT(I)) was developed and implemented In EPA’s Community Multiscale Air Quality (CMAQ) modeling system, version 5.1. The Kinetic PreProcessor (KPP), version 2.2.3 generated a third stage Rosenbrock solver (Rodas3) to integrate the stiff system of ODEs that describe the mass transfer, chemical kinetics, and scavenging processes of CMAQ clouds. This work advances the ability of the entire atmospheric chemistry community to test and implement more sophisticated aqueous chemical mechanisms in CMAQ and further investigate the impacts of microphysical parameters on cloud chemistry because model code was released by CMAS and is open source. Month-long CMAQ simulations for winter and summer periods over the United States reveal the changes in model predictions due to these cloud module updates within the full chemical transport model. While monthly average CMAQ predictions are not drastically altered between AQCHEM and AQCHEM-KMT, hourly concentration differences are statistically significant and at times substantial. With added in-cloud secondary organic aerosol (SOA) formation from biogenic epoxides (AQCHEM-KMTI), normalized mean error and bias statistics are slightly improved for 2-methyltetrols and 2-methylglyceric acid at the Research Triangle Park measurement site in North Carolina during the SOAS field campaign period. The added in-cloud chemistry leads to a monthly average increase of 11-18% in “cloud” SOA at the surface in the eastern United States for June 2013.


Journal Articles on this Report : 17 Displayed | Download in RIS Format

Publications Views
Other project views: All 51 publications 18 publications in selected types All 18 journal articles
Publications
Type Citation Project Document Sources
Journal Article Baker KR, Carlton AG, Kleindienst TE, Offenberg JH, Beaver MR, Gentner DR, Goldstein AH, Hayes PL, Jimenez JL, Gilman JB, de Gouw JA, Woody MC, Pye HOT, Kelly JT, Lewandowski M, Jaoui M, Stevens PS, Brune WH, Lin Y-H, Rubitschun CL, Surratt JD. Gas and aerosol carbon in California: comparison of measurements and model predictions in Pasadena and Bakersfield. Atmospheric Chemistry and Physics 2015;15(9):5243-5258. R835041 (2015)
R835041 (Final)
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  • Journal Article Bash JO, Carlton AG, Hutzell WT, Bullock Jr OR. Regional air quality model application of the aqueous-phase photo reduction of atmospheric oxidized mercury by dicarboxylic acids. Atmosphere 2014;5(1):1-15. R835041 (2014)
    R835041 (2015)
    R835041 (Final)
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  • Journal Article Carlton AG, Turpin BJ. Particle partitioning potential of organic compounds is highest in the Eastern US and driven by anthropogenic water. Atmospheric Chemistry and Physics 2013;13(20):10203-10214. R835041 (2013)
    R835041 (Final)
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  • Journal Article Fahey KM, Carlton AG, Pye HOT, Baek J, Hutzell WT, Stanier CO, Baker KR, Appel KW, Jaoui M, Offenberg JH. A framework for expanding aqueous chemistry in the Community Multiscale Air Quality (CMAQ) model version 5.1. Geoscientific Model Development 2017;10(4):1587-1605. R835041 (Final)
    R833865 (Final)
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  • Journal Article Farkas CM, Moeller MD, Felder FA, Baker KR, Rodgers M, Carlton AG. Temporalization of peak electric generation particulate matter emissions during high energy demand days. Environmental Science & Technology 2015;49(7):4696-4704. R835041 (2014)
    R835041 (2015)
    R835041 (Final)
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  • Journal Article Farkas CM, Moeller MD, Felder FA, Henderson BH, Carlton AG. High electricity demand in the northeast U.S.: PJM Reliability Network and peaking unit impacts on air quality. Environmental Science & Technology 2016;50(15):8375–8384. R835041 (Final)
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  • Journal Article Guo H, Xu L, Bougiatioti A, Cerully KM, Capps SL, Hite Jr. JR, Carlton AG, Lee S-H, Bergin MH, Ng NL, Nenes A, Weber RJ. Fine-particle water and pH in the southeastern United States. Atmospheric Chemistry and Physics 2015;15(9):5211-5228. R835041 (2015)
    R835041 (Final)
    R834799 (2015)
    R834799 (2016)
    R834799 (Final)
    R834799C001 (2015)
    R834799C001 (Final)
    R835410 (2013)
    R835410 (2014)
    R835410 (2015)
    R835410 (Final)
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  • Journal Article He C, Liu J, Carlton AG, Fan S, Horowitz LW, Levy II H, Tao S. Evaluation of factors controlling global secondary organic aerosol production from cloud processes. Atmospheric Chemistry and Physics 2013;13(4):1913-1926. R835041 (Final)
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  • Journal Article Hodas N, Sullivan AP, Skog K, Keutsch FN, Collett Jr JL, Decsesari S, Facchini MC, Carlton AG, Laaksonen A, Turpin BJ. Aerosol liquid water driven by anthropogenic nitrate: implications for lifetimes of water‐soluble organic gases and potential for secondary organic aerosol formation. Environmental Science & Technology 2014;48(19):11127‐11136. R835041 (2014)
    R835041 (2015)
    R835041 (Final)
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  • Journal Article Liu J, Horowitz LW, Fan S, Carlton AG, Levy II H. Global in-cloud production of secondary organic aerosols: implementation of a detailed chemical mechanism in the GFDL atmospheric model AM3. Journal of Geophysical Research-Atmospheres 2012;117(15):D15303. R835041 (2012)
    R835041 (Final)
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  • Journal Article Marmo BP, Carlton AG, Henderson BH. Partitioning of HNO3, H2O2 and SO2 to cloud ice: simulations with CMAQ. Atmospheric Environment 2013;88:239-246. R835041 (2014)
    R835041 (2015)
    R835041 (Final)
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  • Journal Article Nguyen TKV, Zhang Q, Jimenez JL, Pike M, Carlton AG. Liquid water: ubiquitous contributor to aerosol mass. Environmental Science & Technology Letters 2016;3(7):257-263. R835041 (Final)
    R835877 (2016)
    R835877 (2017)
    R835877 (2018)
    R835877 (2019)
    R835877 (Final)
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  • Journal Article Nguyen TKV, Capps SL, Carlton AG. Decreasing aerosol water is consistent with OC trends in the southeast U.S. Environmental Science & Technology 2015;49(13):7843-7850. R835041 (2015)
    R835041 (Final)
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  • Journal Article Nguyen TKV, Ghate VP, Carlton AG. Reconciling satellite aerosol optical thickness and surface fine particle mass through aerosol liquid water. Geophysical Research Letters 2016;43(22):11903–11912. R835041 (Final)
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  • Journal Article Parikh HM, Carlton AG, Zhou Y, Zhang H, Kamens RM, Vizuete W. Modeling secondary organic aerosol formation from xylene and aromatic mixtures using a dynamic partitioning approach incorporating particle aqueous-phase chemistry (II). Atmospheric Environment 2012;56:250-260. R835041 (2012)
    R835041 (Final)
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  • Journal Article Pratt KA, Fiddler MN, Shepson PB, Carlton AG, Surratt JD. Organosulfates in cloud water above the Ozarks’ isoprene source region. Atmospheric Environment 2013;77:231-238. R835041 (2013)
    R835041 (Final)
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  • Journal Article Sareen N, Waxman EM, Turpin BJ, Volkamer R, Carlton AG. Potential of aerosol liquid water to facilitate organic aerosol formation: assessing knowledge gaps about precursors and partitioning. Environmental Science & Technology 2017;51(6):3327-3335. R835041 (Final)
    R835412 (Final)
  • Abstract from PubMed
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  • Supplemental Keywords:

    Cloud processing, secondary organic aerosol, black carbon, particulate carbon, air quality;

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    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.

    Project Research Results

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    51 publications for this project
    18 journal articles for this project

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