592 results on '"de Gouw, Joost A."'
Search Results
2. Societal shifts due to COVID-19 reveal large-scale complexities and feedbacks between atmospheric chemistry and climate change
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Laughner, Joshua L, Neu, Jessica L, Schimel, David, Wennberg, Paul O, Barsanti, Kelley, Bowman, Kevin W, Chatterjee, Abhishek, Croes, Bart E, Fitzmaurice, Helen L, Henze, Daven K, Kim, Jinsol, Kort, Eric A, Liu, Zhu, Miyazaki, Kazuyuki, Turner, Alexander J, Anenberg, Susan, Avise, Jeremy, Cao, Hansen, Crisp, David, de Gouw, Joost, Eldering, Annmarie, Fyfe, John C, Goldberg, Daniel L, Gurney, Kevin R, Hasheminassab, Sina, Hopkins, Francesca, Ivey, Cesunica E, Jones, Dylan BA, Liu, Junjie, Lovenduski, Nicole S, Martin, Randall V, McKinley, Galen A, Ott, Lesley, Poulter, Benjamin, Ru, Muye, Sander, Stanley P, Swart, Neil, Yung, Yuk L, and Zeng, Zhao-Cheng
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Climate Action ,Air Pollution ,Atmosphere ,COVID-19 ,Carbon Dioxide ,Climate Change ,Greenhouse Gases ,Humans ,Methane ,Models ,Theoretical ,Nitrogen Oxides ,Ozone ,air quality ,greenhouse gases ,earth system ,mitigation - Abstract
The COVID-19 global pandemic and associated government lockdowns dramatically altered human activity, providing a window into how changes in individual behavior, enacted en masse, impact atmospheric composition. The resulting reductions in anthropogenic activity represent an unprecedented event that yields a glimpse into a future where emissions to the atmosphere are reduced. Furthermore, the abrupt reduction in emissions during the lockdown periods led to clearly observable changes in atmospheric composition, which provide direct insight into feedbacks between the Earth system and human activity. While air pollutants and greenhouse gases share many common anthropogenic sources, there is a sharp difference in the response of their atmospheric concentrations to COVID-19 emissions changes, due in large part to their different lifetimes. Here, we discuss several key takeaways from modeling and observational studies. First, despite dramatic declines in mobility and associated vehicular emissions, the atmospheric growth rates of greenhouse gases were not slowed, in part due to decreased ocean uptake of CO2 and a likely increase in CH4 lifetime from reduced NO x emissions. Second, the response of O3 to decreased NO x emissions showed significant spatial and temporal variability, due to differing chemical regimes around the world. Finally, the overall response of atmospheric composition to emissions changes is heavily modulated by factors including carbon-cycle feedbacks to CH4 and CO2, background pollutant levels, the timing and location of emissions changes, and climate feedbacks on air quality, such as wildfires and the ozone climate penalty.
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- 2021
3. Teaching Instrumental Analysis during the Pandemic: Application of Handheld CO[subscript 2] Monitors to Explore COVID-19 Transmission Risks
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Jensen, Andrew, Brown, Niamh, Kosacki, Nathalie, Spacek, Sara, Bradley, Alexander, Katz, Daniel, Jimenez, Jose L., and de Gouw, Joost
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The COVID-19 pandemic has posed a challenge for maintaining an engaging learning environment while using remote laboratory formats. In this work, we describe a Student Choice Project (SCP) in an undergraduate instrumental analysis course that was adapted for remote learning without sacrificing research-based learning goals. We discuss the implementation and assessment of this SCP, selected student results, and student feedback. Students were provided handheld carbon dioxide monitors and charged with designing and implementing an investigation centered on COVID-19 airborne transmission. The real-time monitors provided experience with a new analytical tool that demanded considerations and analysis not common to other methods discussed in the course. Students were motivated by the ability to design their own projects and by the real-world implications of their findings. They performed well for all assessments, reported a positive experience, and recommended these monitors be added to the typical repertoire of instrumentation for the course.
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- 2022
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4. Coupled Air Quality and Boundary-Layer Meteorology in Western U.S. Basins during Winter: Design and Rationale for a Comprehensive Study.
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Hallar, A Gannet, Brown, Steven S, Crosman, Erik, Barsanti, Kelley, Cappa, Christopher D, Faloona, Ian, Fast, Jerome, Holmes, Heather A, Horel, John, Lin, John, Middlebrook, Ann, Mitchell, Logan, Murphy, Jennifer, Womack, Caroline C, Aneja, Viney, Baasandorj, Munkhbayar, Bahreini, Roya, Banta, Robert, Bray, Casey, Brewer, Alan, Caulton, Dana, de Gouw, Joost, De Wekker, Stephan FJ, Farmer, Delphine K, Gaston, Cassandra J, Hoch, Sebastian, Hopkins, Francesca, Karle, Nakul N, Kelly, James T, Kelly, Kerry, Lareau, Neil, Lu, Keding, Mauldin, Roy L, Mallia, Derek V, Martin, Randal, Mendoza, Daniel, Oldroyd, Holly J, Pichugina, Yelena, Pratt, Kerri A, Saide, Pablo, Silva, Phillip J, Simpson, William, Stephens, Britton B, Stutz, Jochen, and Sullivan, Amy
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Chemistry ,atmospheric ,Greenhouse gases ,Aircraft observations ,Field experiments ,Mountain meteorology ,Astronomical and Space Sciences ,Atmospheric Sciences ,Physical Geography and Environmental Geoscience ,Meteorology & Atmospheric Sciences - Abstract
Wintertime episodes of high aerosol concentrations occur frequently in urban and agricultural basins and valleys worldwide. These episodes often arise following development of persistent cold-air pools (PCAPs) that limit mixing and modify chemistry. While field campaigns targeting either basin meteorology or wintertime pollution chemistry have been conducted, coupling between interconnected chemical and meteorological processes remains an insufficiently studied research area. Gaps in understanding the coupled chemical-meteorological interactions that drive high pollution events make identification of the most effective air-basin specific emission control strategies challenging. To address this, a September 2019 workshop occurred with the goal of planning a future research campaign to investigate air quality in Western U.S. basins. Approximately 120 people participated, representing 50 institutions and 5 countries. Workshop participants outlined the rationale and design for a comprehensive wintertime study that would couple atmospheric chemistry and boundary-layer and complex-terrain meteorology within western U.S. basins. Participants concluded the study should focus on two regions with contrasting aerosol chemistry: three populated valleys within Utah (Salt Lake, Utah, and Cache Valleys) and the San Joaquin Valley in California. This paper describes the scientific rationale for a campaign that will acquire chemical and meteorological datasets using airborne platforms with extensive range, coupled to surface-based measurements focusing on sampling within the near-surface boundary layer, and transport and mixing processes within this layer, with high vertical resolution at a number of representative sites. No prior wintertime basin-focused campaign has provided the breadth of observations necessary to characterize the meteorological-chemical linkages outlined here, nor to validate complex processes within coupled atmosphere-chemistry models.
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- 2021
5. The 2020 COVID-19 pandemic and atmospheric composition: back to the future
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Laughner, Joshua L, Neu, Jessica L, Schimel, David, Wennberg, Paul O, Barsanti, Kelley, Bowman, Kevin, Chatterjee, Abhishek, Croes, Bart, Fitzmaurice, Helen, Henze, Daven, Kim, Jinsol, Kort, Eric A, Liu, Zhu, Miyazaki, Kazuyuki, Turner, Alexander J, Anenberg, Susan, Avise, Jeremy, Cao, Hansen, Crisp, David, de Gouw, Joost, Eldering, Annmarie, Fyfe, John C, Goldberg, Daniel L, Gurney, Kevin R, Hasheminassab, Sina, Hopkins, Francesca, Ivey, Cesunica E, Jones, Dylan BA, Lovenduski, Nicole S, Martin, Randall V, McKinley, Galen A, Ott, Lesley, Poulter, Benjamin, Ru, Muye, Sander, Stanley P, Swart, Neil, Yung, Yuk L, and Zeng, Zhao-Cheng
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- 2021
6. Biomass-burning-derived particles from a wide variety of fuels – Part 2: Effects of photochemical aging on particle optical and chemical properties
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Cappa, Christopher D, Lim, Christopher Y, Hagan, David H, Coggon, Matthew, Koss, Abigail, Sekimoto, Kanako, de Gouw, Joost, Onasch, Timothy B, Warneke, Carsten, and Kroll, Jesse H
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Earth Sciences ,Atmospheric Sciences ,Aging ,Climate Action ,Astronomical and Space Sciences ,Meteorology & Atmospheric Sciences ,Atmospheric sciences ,Climate change science - Abstract
Particles in smoke emitted from biomass combustion have a large impact on global climate and urban air quality. There is limited understanding of how particle optical properties-especially the contributions of black carbon (BC) and brown carbon (BrC)-evolve with photochemical aging of smoke. We analyze the evolution of the optical properties and chemical composition of particles produced from combustion of a wide variety of biomass fuels, largely from the western United States. The smoke is photochemically aged in a reaction chamber over atmospheric-equivalent timescales ranging from 0.25 to 8 d. Various aerosol optical properties (e.g., the single-scatter albedo, the wavelength dependence of absorption, and the BC mass absorption coefficient, MACBC) evolved with photochemical aging, with the specific evolution dependent on the initial particle properties and conditions. The impact of coatings on BC absorption (the so-called lensing effect) was small, even after photochemical aging. The initial evolution of the BrC absorptivity (MACBrC) varied between individual burns but decreased consistently at longer aging times; the wavelength dependence of the BrC absorption generally increased with aging. The observed changes to BrC properties result from a combination of secondary organic aerosol (SOA) production and heterogeneous oxidation of primary and secondary OA mass, with SOA production being the major driver of the changes. The SOA properties varied with time, reflecting both formation from precursors having a range of lifetimes with respect to OH and the evolving photochemical environment within the chamber. Although the absorptivity of BrC generally decreases with aging, the dilution-corrected absorption may actually increase from the production of SOA. These experimental results provide context for the interpretation of ambient observations of the evolution of particle optical properties in biomass-combustion-derived smoke plumes.
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- 2020
7. Societal shifts due to COVID-19 reveal large-scale complexities and feedbacks between atmospheric chemistry and climate change
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rest of the Keck Institute for Space Studies “COVID-19: Identifying Unique Opportunities for Earth System Science” study team, Laughner, Joshua L., Neu, Jessica L., Schimel, David, Wennberg, Paul O., Barsanti, Kelley, Bowman, Kevin W., Chatterjee, Abhishek, Croes, Bart E., Fitzmaurice, Helen L., Henze, Daven K., Kim, Jinsol, Kort, Eric A., Liu, Zhu, Miyazaki, Kazuyuki, Turner, Alexander J., Anenberg, Susan, Avise, Jeremy, Cao, Hansen, Crisp, David, de Gouw, Joost, Eldering, Annmarie, Fyfe, John C., Goldberg, Daniel L., Gurney, Kevin R., Hasheminassab, Sina, Hopkins, Francesca, Ivey, Cesunica E., Jones, Dylan B. A., Liu, Junjie, Lovenduski, Nicole S., Martin, Randall V., McKinley, Galen A., Ott, Lesley, Poulter, Benjamin, Ru, Muye, Sander, Stanley P., Swart, Neil, Yung, Yuk L., and Zeng, Zhao-Cheng
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- 2021
8. On the sources and sinks of atmospheric VOCs: an integrated analysis of recent aircraft campaigns over North America.
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Chen, Xin, Millet, Dylan B, Singh, Hanwant B, Wisthaler, Armin, Apel, Eric C, Atlas, Elliot L, Blake, Donald R, Bourgeois, Ilann, Brown, Steven S, Crounse, John D, de Gouw, Joost A, Flocke, Frank M, Fried, Alan, Heikes, Brian G, Hornbrook, Rebecca S, Mikoviny, Tomas, Min, Kyung-Eun, Müller, Markus, Neuman, J Andrew, O'Sullivan, Daniel W, Peischl, Jeff, Pfister, Gabriele G, Richter, Dirk, Roberts, James M, Ryerson, Thomas B, Shertz, Stephen R, Thompson, Chelsea R, Treadaway, Victoria, Veres, Patrick R, Walega, James, Warneke, Carsten, Washenfelder, Rebecca A, Weibring, Petter, and Yuan, Bin
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Meteorology & Atmospheric Sciences ,Atmospheric Sciences ,Astronomical and Space Sciences - Abstract
We apply a high-resolution chemical transport model (GEOS-Chem CTM) with updated treatment of volatile organic compounds (VOCs) and a comprehensive suite of airborne datasets over North America to (i) characterize the VOC budget and (ii) test the ability of current models to capture the distribution and reactivity of atmospheric VOCs over this region. Biogenic emissions dominate the North American VOC budget in the model, accounting for 70 % and 95 % of annually emitted VOC carbon and reactivity, respectively. Based on current inventories anthropogenic emissions have declined to the point where biogenic emissions are the dominant summertime source of VOC reactivity even in most major North American cities. Methane oxidation is a 2x larger source of nonmethane VOCs (via production of formaldehyde and methyl hydroperoxide) over North America in the model than are anthropogenic emissions. However, anthropogenic VOCs account for over half of the ambient VOC loading over the majority of the region owing to their longer aggregate lifetime. Fires can be a significant VOC source episodically but are small on average. In the planetary boundary layer (PBL), the model exhibits skill in capturing observed variability in total VOC abundance (R 2 = 0:36) and reactivity (R 2 = 0:54). The same is not true in the free troposphere (FT), where skill is low and there is a persistent low model bias (~ 60 %), with most (27 of 34) model VOCs underestimated by more than a factor of 2. A comparison of PBL: FT concentration ratios over the southeastern US points to a misrepresentation of PBL ventilation as a contributor to these model FT biases. We also find that a relatively small number of VOCs (acetone, methanol, ethane, acetaldehyde, formaldehyde, isoprene C oxidation products, methyl hydroperoxide) drive a large fraction of total ambient VOC reactivity and associated model biases; research to improve understanding of their budgets is thus warranted. A source tracer analysis suggests a current overestimate of biogenic sources for hydroxyacetone, methyl ethyl ketone and glyoxal, an underestimate of biogenic formic acid sources, and an underestimate of peroxyacetic acid production across biogenic and anthropogenic precursors. Future work to improve model representations of vertical transport and to address the VOC biases discussed are needed to advance predictions of ozone and SOA formation.
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- 2019
9. Simulating the Weekly Cycle of NOx-VOC-HOx-O-3 Photochemical System in the South Coast of California During CalNex-2010 Campaign
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Cai, Chenxia, Avise, Jeremy, Kaduwela, Ajith, DaMassa, John, Warneke, Carsten, Gilman, Jessica B, Kuster, William, de Gouw, Joost, Volkamer, Rainer, Stevens, Philip, Lefer, Barry, Holloway, John S, Pollack, Ilana B, Ryerson, Thomas, Atlas, Elliot, Blake, Donald, Rappenglueck, Bernhard, Brown, Steven S, and Dube, William P
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South Coast Air Basin ,Weekend effect ,Ozone ,Nitrogen oxide ,Volatile organic compounds ,hydroxyl and hydroperoxy radicals ,Brain Disorders - Published
- 2019
10. Nighttime Chemical Transformation in Biomass Burning Plumes: A Box Model Analysis Initialized with Aircraft Observations
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Decker, Zachary C. J, Zarzana, Kyle J, Coggon, Matthew, Min, Kyung-Eun, Pollack, Ilana, Ryerson, Thomas B, Peischl, Jeff, Edwards, Pete, Dubé, William P, Markovic, Milos Z, Roberts, James M, Veres, Patrick R, Graus, Martin, Warneke, Carsten, de Gouw, Joost, Hatch, Lindsay E, Barsanti, Kelley C, and Brown, Steven S
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CE-CERT - Published
- 2019
11. Secondary organic aerosol production from local emissions dominates the organic aerosol budget over Seoul, South Korea, during KORUS-AQ
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Nault, Benjamin A, Campuzano-Jost, Pedro, Day, Douglas A, Schroder, Jason C, Anderson, Bruce, Beyersdorf, Andreas J, Blake, Donald R, Brune, William H, Choi, Yonghoon, Corr, Chelsea A, de Gouw, Joost A, Dibb, Jack, DiGangi, Joshua P, Diskin, Glenn S, Fried, Alan, Huey, L Gregory, Kim, Michelle J, Knote, Christoph J, Lamb, Kara D, Lee, Taehyoung, Park, Taehyun, Pusede, Sally E, Scheuer, Eric, Thornhill, Kenneth L, Woo, Jung-Hun, and Jimenez, Jose L
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Meteorology & Atmospheric Sciences ,Atmospheric Sciences ,Astronomical and Space Sciences - Abstract
Abstract. Organic aerosol (OA) is an important fraction of submicron aerosols. However,it is challenging to predict and attribute the specific organic compounds andsources that lead to observed OA loadings, largely due to contributions fromsecondary production. This is especially true for megacities surrounded bynumerous regional sources that create an OA background. Here, we utilizein situ gas and aerosol observations collected on board the NASA DC-8 duringthe NASA–NIER KORUS-AQ (Korea–United States Air Quality) campaign toinvestigate the sources and hydrocarbon precursors that led to the secondaryOA (SOA) production observed over Seoul. First, we investigate thecontribution of transported OA to total loadings observed over Seoul byusing observations over the Yellow Sea coupled to FLEXPART Lagrangiansimulations. During KORUS-AQ, the average OA loading advected into Seoul was∼1–3 µg sm−3. Second, taking this background intoaccount, the dilution-corrected SOA concentration observed over Seoul was∼140 µgsm-3ppmv-1 at 0.5 equivalent photochemicaldays. This value is at the high end of what has been observed in othermegacities around the world (20–70 µgsm-3ppmv-1 at 0.5equivalent days). For the average OA concentration observed over Seoul(13 µg sm−3), it is clear that production of SOA from locallyemitted precursors is the major source in the region. The importanceof local SOA production was supported by the following observations.(1) FLEXPART source contribution calculations indicate anyhydrocarbons with a lifetime of less than 1 day, which are shown to dominate theobserved SOA production, mainly originate from South Korea. (2) SOAcorrelated strongly with other secondary photochemical species, includingshort-lived species (formaldehyde, peroxy acetyl nitrate, sum of acyl peroxynitrates, dihydroxytoluene, and nitrate aerosol). (3) Results froman airborne oxidation flow reactor (OFR), flown for the first time, show afactor of 4.5 increase in potential SOA concentrations over Seoul versus overthe Yellow Sea, a region where background air masses that are advected intoSeoul can be measured. (4) Box model simulations reproduce SOAobserved over Seoul within 11 % on average and suggest that short-livedhydrocarbons (i.e., xylenes, trimethylbenzenes, and semi-volatile and intermediate-volatility compounds) were the main SOA precursors over Seoul. Toluenealone contributes 9 % of the modeled SOA over Seoul. Finally, along withthese results, we use the metric ΔOA/ΔCO2 toexamine the amount of OA produced per fuel consumed in a megacity, whichshows less variability across the world than ΔOA∕ΔCO.
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- 2018
12. Laboratory Investigations of Titan Haze Formation: In Situ Measurement of Gas and Particle Composition
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Horst, Sarah M., Yoon, Y. Heidi, Ugelow, Melissa S., Parker, Alex H., Li, Rui, de Gouw, Joost A., and Tolbert, Margaret A.
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Astrophysics - Earth and Planetary Astrophysics - Abstract
Prior to the arrival of Cassini-Huygens, aerosol production in Titan's atmosphere was believed to begin in the stratosphere where chemical processes are predominantly initiated by FUV radiation. However, measurements taken by Cassini UVIS and CAPS indicate that haze formation initiates in the thermosphere where there is a greater flux of EUV photons and energetic particles available to initiate chemical reactions, including the destruction of N2. The discovery of previously unpredicted nitrogen species in Titan's atmosphere by Cassini INMS indicates that nitrogen participates in the chemistry to a much greater extent than was appreciated before Cassini. The degree of nitrogen in the haze is important for understanding the diversity of molecules present in Titan's atmosphere and on its surface. We have conducted a series of simulation experiments using either spark discharge or FUV photons to initiate chemistry in CH4/N2 gas mixtures (0.01% CH4/99.99% N2 to 10% CH4/90% N2). We obtained in situ real-time measurements using an HR-ToF-AMS to measure the particle composition as a function of particle size and a PIT-MS to measure the composition of gas phase products. These two techniques allow us to investigate the effect of energy source and initial CH4 concentration on the degree of nitrogen incorporation in both the gas and solid phase products. The results presented here confirm that FUV photons produce not only solid phase nitrogen bearing products but also gas phase nitrogen species. We find that in both the gas and solid phase, nitrogen is found in nitriles rather than amines and both the gas phase and solid phase products are composed primarily of molecules with a low degree of aromaticity. The UV experiments reproduce the absolute abundances measured in Titan's stratosphere for a number of gas phase species including C4H2, C6H6, HCN, CH3CN, HC3N, and C2H5CN. [Edited for length], Comment: 55 pages, 18 figures, 4 tables, Accepted in Icarus
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- 2017
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13. Monoterpenes are the largest source of summertime organic aerosol in the southeastern United States
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Zhang, Haofei, Yee, Lindsay D, Lee, Ben H, Curtis, Michael P, Worton, David R, Isaacman-VanWertz, Gabriel, Offenberg, John H, Lewandowski, Michael, Kleindienst, Tadeusz E, Beaver, Melinda R, Holder, Amara L, Lonneman, William A, Docherty, Kenneth S, Jaoui, Mohammed, Pye, Havala OT, Hu, Weiwei, Day, Douglas A, Campuzano-Jost, Pedro, Jimenez, Jose L, Guo, Hongyu, Weber, Rodney J, de Gouw, Joost, Koss, Abigail R, Edgerton, Eric S, Brune, William, Mohr, Claudia, Lopez-Hilfiker, Felipe D, Lutz, Anna, Kreisberg, Nathan M, Spielman, Steve R, Hering, Susanne V, Wilson, Kevin R, Thornton, Joel A, and Goldstein, Allen H
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Earth Sciences ,Atmospheric Sciences ,Climate Action ,Aerosols ,Air Pollutants ,Monoterpenes ,Seasons ,Southeastern United States ,Time Factors ,aerosol source apportionment ,biogenic volatile organic compound oxidation ,nitrogen oxides - Abstract
The chemical complexity of atmospheric organic aerosol (OA) has caused substantial uncertainties in understanding its origins and environmental impacts. Here, we provide constraints on OA origins through compositional characterization with molecular-level details. Our results suggest that secondary OA (SOA) from monoterpene oxidation accounts for approximately half of summertime fine OA in Centreville, AL, a forested area in the southeastern United States influenced by anthropogenic pollution. We find that different chemical processes involving nitrogen oxides, during days and nights, play a central role in determining the mass of monoterpene SOA produced. These findings elucidate the strong anthropogenic-biogenic interaction affecting ambient aerosol in the southeastern United States and point out the importance of reducing anthropogenic emissions, especially under a changing climate, where biogenic emissions will likely keep increasing.
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- 2018
14. Southeast Atmosphere Studies: learning from model-observation syntheses.
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Mao, Jingqiu, Carlton, Annmarie, Cohen, Ronald C, Brune, William H, Brown, Steven S, Wolfe, Glenn M, Jimenez, Jose L, Pye, Havala OT, Ng, Nga Lee, Xu, Lu, McNeill, V Faye, Tsigaridis, Kostas, McDonald, Brian C, Warneke, Carsten, Guenther, Alex, Alvarado, Matthew J, de Gouw, Joost, Mickley, Loretta J, Leibensperger, Eric M, Mathur, Rohit, Nolte, Christopher G, Portmann, Robert W, Unger, Nadine, Tosca, Mika, and Horowitz, Larry W
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Climate Action ,Astronomical and Space Sciences ,Atmospheric Sciences ,Meteorology & Atmospheric Sciences - Abstract
Concentrations of atmospheric trace species in the United States have changed dramatically over the past several decades in response to pollution control strategies, shifts in domestic energy policy and economics, and economic development (and resulting emission changes) elsewhere in the world. Reliable projections of the future atmosphere require models to not only accurately describe current atmospheric concentrations, but to do so by representing chemical, physical and biological processes with conceptual and quantitative fidelity. Only through incorporation of the processes controlling emissions and chemical mechanisms that represent the key transformations among reactive molecules can models reliably project the impacts of future policy, energy and climate scenarios. Efforts to properly identify and implement the fundamental and controlling mechanisms in atmospheric models benefit from intensive observation periods, during which collocated measurements of diverse, speciated chemicals in both the gas and condensed phases are obtained. The Southeast Atmosphere Studies (SAS, including SENEX, SOAS, NOMADSS and SEAC4RS) conducted during the summer of 2013 provided an unprecedented opportunity for the atmospheric modeling community to come together to evaluate, diagnose and improve the representation of fundamental climate and air quality processes in models of varying temporal and spatial scales. This paper is aimed at discussing progress in evaluating, diagnosing and improving air quality and climate modeling using comparisons to SAS observations as a guide to thinking about improvements to mechanisms and parameterizations in models. The effort focused primarily on model representation of fundamental atmospheric processes that are essential to the formation of ozone, secondary organic aerosol (SOA) and other trace species in the troposphere, with the ultimate goal of understanding the radiative impacts of these species in the southeast and elsewhere. Here we address questions surrounding four key themes: gas-phase chemistry, aerosol chemistry, regional climate and chemistry interactions, and natural and anthropogenic emissions. We expect this review to serve as a guidance for future modeling efforts.
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- 2018
15. Air Pollution Inequality in the Denver Metroplex and its Relationship to Historical Redlining
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Bradley, Alexander C., primary, Croes, Bart E., additional, Harkins, Colin, additional, McDonald, Brian C., additional, and de Gouw, Joost A., additional
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- 2024
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16. Ethene, propene, butene and isoprene emissions from a ponderosa pine forest measured by relaxed eddy accumulation
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Rhew, Robert C, Deventer, Malte Julian, Turnipseed, Andrew A, Warneke, Carsten, Ortega, John, Shen, Steve, Martinez, Luis, Koss, Abigail, Lerner, Brian M, Gilman, Jessica B, Smith, James N, Guenther, Alex B, and de Gouw, Joost A
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Astronomical and Space Sciences ,Atmospheric Sciences ,Meteorology & Atmospheric Sciences - Abstract
Alkenes are reactive hydrocarbons that influence local and regional atmospheric chemistry by playing important roles in the photochemical production of tropospheric ozone and in the formation of secondary organic aerosols. The simplest alkene, ethene (ethylene), is a major plant hormone and ripening agent for agricultural commodities. The group of light alkenes (C2-C4) originates from both biogenic and anthropogenic sources, but their biogenic sources are poorly characterized, with limited field-based flux observations. Here we report net ecosystem fluxes of light alkenes and isoprene from a semiarid ponderosa pine forest in the Rocky Mountains of Colorado, USA using the relaxed eddy accumulation (REA) technique during the summer of 2014. Ethene, propene, butene and isoprene emissions have strong diurnal cycles, with median daytime fluxes of 123, 95, 39 and 17 μg mg-2 hg-1, respectively. The fluxes were correlated with each other, followed general ecosystem trends of CO2 and water vapor, and showed similar sunlight and temperature response curves as other biogenic VOCs. The May through October flux, based on measurements and modeling, averaged 62, 52, 24 and 18 μg mg-2 hg-1 for ethene, propene, butene and isoprene, respectively. The light alkenes contribute significantly to the overall biogenic source of reactive hydrocarbons: roughly 18 % of the dominant biogenic VOC, 2-methyl-3-buten-2-ol. The measured ecosystem scale fluxes are 40-80 % larger than estimates used for global emissions models for this type of ecosystem.
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- 2017
17. Secondary Organic Aerosol Formation from the OH Oxidation of Phenol, Catechol, Styrene, Furfural, and Methyl Furfural.
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Schueneman, Melinda K., Day, Douglas A., Peng, Zhe, Pagonis, Demetrios, Jenks, Olivia J., de Gouw, Joost A., and Jimenez, Jose L.
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- 2024
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18. Modeling the Impacts of Volatile Chemical Product Emissions on Atmospheric Photochemistry and Ozone Formation in Los Angeles.
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Chen, Tianshu, Gilman, Jessica, Kim, Si‐Wan, Lefer, Barry, Washenfelder, Rebecca, Young, Cora J., Rappenglueck, Bernhard, Stevens, Philip S., Veres, Patrick R., Xue, Likun, and de Gouw, Joost
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ATMOSPHERIC ozone ,PHOTOCHEMICAL smog ,NITROGEN oxides emission control ,EMISSIONS (Air pollution) ,VOLATILE organic compounds ,CHEMICAL models ,EMISSION control - Abstract
The dominant fraction of anthropogenic volatile organic compound (VOC) emissions shifted from transportation fuels to volatile chemical products (VCP) in Los Angeles (LA) in 2010. This shift in VOC composition raises the question about the importance of VCP emissions for ozone (O3) formation. In this study, O3 chemistry during the CalNex 2010 was modeled using the Master Chemical Mechanism (MCM) version 3.3.1 and a detailed representation of VCP emissions based on measurements combined with inventory estimates. The model calculations indicate that VCP emissions contributed to 23% of the mean daily maximum 8‐hr average O3 (DMA8 O3) during the O3 episodes. The simulated OH reactivity, including the contribution from VCP emissions, aligns with observations. Additionally, this framework was employed using four lumped mechanisms with simplified representations of emissions and chemistry. RACM2‐VCP showed the closest agreement with MCM, with a slight 4% increase in average DMA8 O3 (65 ± 13 ppb), whereas RACM2 (58 ± 13 ppb) and SAPRC07B (59 ± 14 ppb) exhibited slightly lower levels. CB6r2, however, recorded reduced concentrations (37 ± 10 ppb). Although emissions of O3 precursors have declined in LA since 2010, O3 levels have not decreased significantly. Model results ascribed this trend to the rapid reduction in NOX emissions. Moreover, given the impact of COVID‐19, an analysis of 2020 reveals a shift to a NOX‐limited O3 formation regime in LA, thereby diminishing the influence of VCPs. This study provides new insights into the impact of VCP emissions on O3 pollution from an in‐depth photochemical perspective. Plain Language Summary: In the 2010 CalNex study, researchers found that volatile organic compounds (VOCs) were predominantly emitted from volatile chemical products (VCPs) like solvents. In our subsequent research, using a detailed chemical model, we discovered that about a quarter of the mean daily maximum 8‐hr average ozone was contributed by these everyday products during ozone episodes. This insight is critical as it underscores how these emissions significantly speed up ozone formation through accelerated chemical reactions. We also evaluated various simplified chemical mechanisms for ozone prediction, finding that the one incorporating key reactions of VOC species was most accurate. Further, our analysis suggests that the slight increase in Los Angeles' ozone levels since 2010 can likely be attributed to faster reductions in NOX emissions relative to VOCs. Notably, the reduction in NOX emissions by 2020 considerably diminished the impact of VCPs on ozone levels. However, given the uncertain future of NOX emissions and the ongoing rise in emissions from everyday products, it remains essential to control these emissions. Key Points: Volatile chemical product emissions accounted for 23% of mean daily max 8‐hr ozone in ozone episodes, as per the 2010 CalNex studyVCP emissions boost ozone formation by increasing primary production and efficient recycling of ROx radicals, thus enhancing pollution2020s reduction in NOx emissions in Los Angeles, potentially due to COVID‐19, led to a NOx‐limited state, lessening VCPs' impact on ozone [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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19. Continued emissions of carbon tetrachloride from the United States nearly two decades after its phaseout for dispersive uses
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Hu, Lei, Montzka, Stephen A, Miller, Ben R, Andrews, Arlyn E, Miller, John B, Lehman, Scott J, Sweeney, Colm, Miller, Scot M, Thoning, Kirk, Siso, Carolina, Atlas, Elliot L, Blake, Donald R, de Gouw, Joost, Gilman, Jessica B, Dutton, Geoff, Elkins, James W, Hall, Bradley, Chen, Huilin, Fischer, Marc L, Mountain, Marikate E, Nehrkorn, Thomas, Biraud, Sebastien C, Moore, Fred L, and Tans, Pieter
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Earth Sciences ,Atmospheric Sciences ,carbon tetrachloride ,emissions ,United States ,ozone-depleting substances ,greenhouse gases - Abstract
National-scale emissions of carbon tetrachloride (CCl4) are derived based on inverse modeling of atmospheric observations at multiple sites across the United States from the National Oceanic and Atmospheric Administration's flask air sampling network. We estimate an annual average US emission of 4.0 (2.0-6.5) Gg CCl4 y(-1) during 2008-2012, which is almost two orders of magnitude larger than reported to the US Environmental Protection Agency (EPA) Toxics Release Inventory (TRI) (mean of 0.06 Gg y(-1)) but only 8% (3-22%) of global CCl4 emissions during these years. Emissive regions identified by the observations and consistently shown in all inversion results include the Gulf Coast states, the San Francisco Bay Area in California, and the Denver area in Colorado. Both the observation-derived emissions and the US EPA TRI identified Texas and Louisiana as the largest contributors, accounting for one- to two-thirds of the US national total CCl4 emission during 2008-2012. These results are qualitatively consistent with multiple aircraft and ship surveys conducted in earlier years, which suggested significant enhancements in atmospheric mole fractions measured near Houston and surrounding areas. Furthermore, the emission distribution derived for CCl4 throughout the United States is more consistent with the distribution of industrial activities included in the TRI than with the distribution of other potential CCl4 sources such as uncapped landfills or activities related to population density (e.g., use of chlorine-containing bleach).
- Published
- 2016
20. Highly functionalized organic nitrates in the southeast United States: Contribution to secondary organic aerosol and reactive nitrogen budgets.
- Author
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Iyer, Siddharth, Kurtén, Theo, Hu, Weiwei, Day, Douglas, Campuzano-Jost, Pedro, Jimenez, Jose, Xu, Lu, Ng, Nga, Guo, Hongyu, Weber, Rodney, Wild, Robert, Brown, Steven, Koss, Abigail, de Gouw, Joost, Olson, Kevin, McAvey, Kevin, Shepson, Paul, Starn, Tim, Baumann, Karsten, Edgerton, Eric, Liu, Jiumeng, Shilling, John, Miller, David, Brune, William, Schobesberger, Siegfried, DAmbro, Emma, Thornton, Joel, Lee, Ben, Mohr, Claudia, Lopez-Hilfiker, Felipe, Lutz, Anna, Hallquist, Mattias, Lee, Lance, Romer, Paul, Seco, Roger, Kim, Saewung, Cohen, Ronald, and Goldstein, Allen
- Subjects
biogenic volatile organic compound oxidation ,high-resolution time-of-flight chemical ionization mass spectrometer ,lifetime calculation ,online measurement ,particulate organic nitrates - Abstract
Speciated particle-phase organic nitrates (pONs) were quantified using online chemical ionization MS during June and July of 2013 in rural Alabama as part of the Southern Oxidant and Aerosol Study. A large fraction of pONs is highly functionalized, possessing between six and eight oxygen atoms within each carbon number group, and is not the common first generation alkyl nitrates previously reported. Using calibrations for isoprene hydroxynitrates and the measured molecular compositions, we estimate that pONs account for 3% and 8% of total submicrometer organic aerosol mass, on average, during the day and night, respectively. Each of the isoprene- and monoterpenes-derived groups exhibited a strong diel trend consistent with the emission patterns of likely biogenic hydrocarbon precursors. An observationally constrained diel box model can replicate the observed pON assuming that pONs (i) are produced in the gas phase and rapidly establish gas-particle equilibrium and (ii) have a short particle-phase lifetime (∼2-4 h). Such dynamic behavior has significant implications for the production and phase partitioning of pONs, organic aerosol mass, and reactive nitrogen speciation in a forested environment.
- Published
- 2016
21. Highly functionalized organic nitrates in the southeast United States: Contribution to secondary organic aerosol and reactive nitrogen budgets
- Author
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Lee, Ben H, Mohr, Claudia, Lopez-Hilfiker, Felipe D, Lutz, Anna, Hallquist, Mattias, Lee, Lance, Romer, Paul, Cohen, Ronald C, Iyer, Siddharth, Kurtén, Theo, Hu, Weiwei, Day, Douglas A, Campuzano-Jost, Pedro, Jimenez, Jose L, Xu, Lu, Ng, Nga Lee, Guo, Hongyu, Weber, Rodney J, Wild, Robert J, Brown, Steven S, Koss, Abigail, de Gouw, Joost, Olson, Kevin, Goldstein, Allen H, Seco, Roger, Kim, Saewung, McAvey, Kevin, Shepson, Paul B, Starn, Tim, Baumann, Karsten, Edgerton, Eric S, Liu, Jiumeng, Shilling, John E, Miller, David O, Brune, William, Schobesberger, Siegfried, D'Ambro, Emma L, and Thornton, Joel A
- Subjects
particulate organic nitrates ,online measurement ,lifetime calculation ,high-resolution time-of-flight chemical ionization mass spectrometer ,biogenic volatile organic compound oxidation - Abstract
Speciated particle-phase organic nitrates (pONs) were quantified using online chemical ionization MS during June and July of 2013 in rural Alabama as part of the Southern Oxidant and Aerosol Study. A large fraction of pONs is highly functionalized, possessing between six and eight oxygen atoms within each carbon number group, and is not the common first generation alkyl nitrates previously reported. Using calibrations for isoprene hydroxynitrates and the measured molecular compositions, we estimate that pONs account for 3% and 8% of total submicrometer organic aerosol mass, on average, during the day and night, respectively. Each of the isoprene- and monoterpenes-derived groups exhibited a strong diel trend consistent with the emission patterns of likely biogenic hydrocarbon precursors. An observationally constrained diel box model can replicate the observed pON assuming that pONs (i) are produced in the gas phase and rapidly establish gas-particle equilibrium and (ii) have a short particle-phase lifetime (∼2-4 h). Such dynamic behavior has significant implications for the production and phase partitioning of pONs, organic aerosol mass, and reactive nitrogen speciation in a forested environment.
- Published
- 2016
22. Volatility and lifetime against OH heterogeneous reaction of ambient isoprene-epoxydiols-derived secondary organic aerosol (IEPOX-SOA)
- Author
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Hu, Weiwei, Palm, Brett B, Day, Douglas A, Campuzano-Jost, Pedro, Krechmer, Jordan E, Peng, Zhe, de Sá, Suzane S, Martin, Scot T, Alexander, M Lizabeth, Baumann, Karsten, Hacker, Lina, Kiendler-Scharr, Astrid, Koss, Abigail R, de Gouw, Joost A, Goldstein, Allen H, Seco, Roger, Sjostedt, Steven J, Park, Jeong-Hoo, Guenther, Alex B, Kim, Saewung, Canonaco, Francesco, Prévôt, André SH, Brune, William H, and Jimenez, Jose L
- Subjects
Climate Action ,Astronomical and Space Sciences ,Atmospheric Sciences ,Meteorology & Atmospheric Sciences - Abstract
Isoprene-epoxydiols-derived secondary organic aerosol (IEPOX-SOA) can contribute substantially to organic aerosol (OA) concentrations in forested areas under low NO conditions, hence significantly influencing the regional and global OA budgets, accounting, for example, for 16-36% of the submicron OA in the southeastern United States (SE US) summer. Particle evaporation measurements from a thermodenuder show that the volatility of ambient IEPOX-SOA is lower than that of bulk OA and also much lower than that of known monomer IEPOX-SOA tracer species, indicating that IEPOX-SOA likely exists mostly as oligomers in the aerosol phase. The OH aging process of ambient IEPOX-SOA was investigated with an oxidation flow reactor (OFR). New IEPOX-SOA formation in the reactor was negligible, as the OFR does not accelerate processes such as aerosol uptake and reactions that do not scale with OH. Simulation results indicate that adding ∼ 100μgm-3 of pure H2SO4 to the ambient air allows IEPOX-SOA to be efficiently formed in the reactor. The heterogeneous reaction rate coefficient of ambient IEPOX-SOA with OH radical (kOH) was estimated as 4.0±2.0 × 10-13cm3molec-1s-1, which is equivalent to more than a 2-week lifetime. A similar kOH was found for measurements of OH oxidation of ambient Amazon forest air in an OFR. At higher OH exposures in the reactor (> 1 × 1012molec cm-3s), the mass loss of IEPOX-SOA due to heterogeneous reaction was mainly due to revolatilization of fragmented reaction products. We report, for the first time, OH reactive uptake coefficients (γOH = 0.59±0.33 in SE US and γOH = 0.68±0.38 in Amazon) for SOA under ambient conditions. A relative humidity dependence of kOH and γOH was observed, consistent with surface-area-limited OH uptake. No decrease of kOH was observed as OH concentrations increased. These observations of physicochemical properties of IEPOX-SOA can help to constrain OA impact on air quality and climate.
- Published
- 2016
23. Analyzing the Impact of Evolving Combustion Conditions on the Composition of Wildfire Emissions Using Satellite Data
- Author
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Anderson, Lindsey D., primary, Dix, Barbara, additional, Schnell, Jordan, additional, Yokelson, Robert, additional, Veefkind, J. Pepijn, additional, Ahmadov, Ravan, additional, and de Gouw, Joost, additional
- Published
- 2023
- Full Text
- View/download PDF
24. Sources of Formaldehyde in U.S. Oil and Gas Production Regions
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Dix, Barbara, primary, Li, Meng, additional, Roosenbrand, Esther, additional, Francoeur, Colby, additional, Brown, Steven S., additional, Gilman, Jessica B., additional, Hanisco, Thomas F., additional, Keutsch, Frank, additional, Koss, Abigail, additional, Lerner, Brian M., additional, Peischl, Jeff, additional, Roberts, James M., additional, Ryerson, Thomas B., additional, St. Clair, Jason M., additional, Veres, Patrick R., additional, Warneke, Carsten, additional, Wild, Robert J., additional, Wolfe, Glenn M., additional, Yuan, Bin, additional, Veefkind, J. Pepijn, additional, Levelt, Pieternel F., additional, McDonald, Brian C., additional, and de Gouw, Joost, additional
- Published
- 2023
- Full Text
- View/download PDF
25. Measurements of volatile organic compounds in ambient air by gas-chromatography and real-time Vocus PTR-TOF-MS: calibrations, instrument background corrections, and introducing a PTR Data Toolkit
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Jensen, Andrew R., primary, Koss, Abigail R., additional, Hales, Ryder B., additional, and de Gouw, Joost A., additional
- Published
- 2023
- Full Text
- View/download PDF
26. Anthropogenic enhancements to production of highly oxygenated molecules from autoxidation
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Pye, Havala O. T., D’Ambro, Emma L., Lee, Ben H., Schobesberger, Siegfried, Takeuchi, Masayuki, Zhao, Yue, Lopez-Hilfiker, Felipe, Liu, Jiumeng, Shilling, John E., Xing, Jia, Mathur, Rohit, Middlebrook, Ann M., Liao, Jin, Welti, André, Graus, Martin, Warneke, Carsten, de Gouw, Joost A., Holloway, John S., Ryerson, Thomas B., Pollack, Ilana B., and Thornton, Joel A.
- Published
- 2019
27. Satellite isoprene retrievals constrain emissions and atmospheric oxidation
- Author
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Wells, Kelley C., Millet, Dylan B., Payne, Vivienne H., Deventer, M. Julian, Bates, Kelvin H., de Gouw, Joost A., and Graus, Martin
- Subjects
Artificial satellites -- Usage ,Emissions (Pollution) -- Control ,Environmental issues ,Science and technology ,Zoology and wildlife conservation - Abstract
Isoprene is the dominant non-methane organic compound emitted to the atmosphere.sup.1-3. It drives ozone and aerosol production, modulates atmospheric oxidation and interacts with the global nitrogen cycle.sup.4-8. Isoprene emissions are highly uncertain.sup.1,9, as is the nonlinear chemistry coupling isoprene and the hydroxyl radical, OH--its primary sink.sup.10-13. Here we present global isoprene measurements taken from space using the Cross-track Infrared Sounder. Together with observations of formaldehyde, an isoprene oxidation product, these measurements provide constraints on isoprene emissions and atmospheric oxidation. We find that the isoprene-formaldehyde relationships measured from space are broadly consistent with the current understanding of isoprene-OH chemistry, with no indication of missing OH recycling at low nitrogen oxide concentrations. We analyse these datasets over four global isoprene hotspots in relation to model predictions, and present a quantification of isoprene emissions based directly on satellite measurements of isoprene itself. A major discrepancy emerges over Amazonia, where current underestimates of natural nitrogen oxide emissions bias modelled OH and hence isoprene. Over southern Africa, we find that a prominent isoprene hotspot is missing from bottom-up predictions. A multi-year analysis sheds light on interannual isoprene variability, and suggests the influence of the El Niño/Southern Oscillation. Direct satellite measurements of atmospheric isoprene are compared with model predictions, showing broad agreement but highlighting spatial and temporal biases in modelled isoprene and nitrogen oxide emissions., Author(s): Kelley C. Wells [sup.1] , Dylan B. Millet [sup.1] , Vivienne H. Payne [sup.2] , M. Julian Deventer [sup.1] [sup.11] , Kelvin H. Bates [sup.3] , Joost A. de [...]
- Published
- 2020
- Full Text
- View/download PDF
28. Airborne flux measurements of methane and volatile organic compounds over the Haynesville and Marcellus shale gas production regions
- Author
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Yuan, Bin, Kaser, Lisa, Karl, Thomas, Graus, Martin, Peischl, Jeff, Campos, Teresa L, Shertz, Steve, Apel, Eric C, Hornbrook, Rebecca S, Hills, Alan, Gilman, Jessica B, Lerner, Brian M, Warneke, Carsten, Flocke, Frank M, Ryerson, Thomas B, Guenther, Alex B, and de Gouw, Joost A
- Subjects
Climate Action ,airborne flux measurements ,eddy covariance ,methane ,shale gas ,Atmospheric Sciences ,Physical Geography and Environmental Geoscience - Abstract
Emissions of methane (CH4) and volatile organic compounds (VOCs) from oil and gas production may have large impacts on air quality and climate change. Methane and VOCs were measured over the Haynesville and Marcellus shale gas plays on board the National Center for Atmospheric Research C-130 and NOAA WP-3D research aircraft in June–July of 2013. We used an eddy covariance technique to measure in situ fluxes of CH4 and benzene from both C-130 flights with high-resolution data (10 Hz) and WP-3D flights with low-resolution data (1 Hz). Correlation (R = 0.65) between CH4 and benzene fluxes was observed when flying over shale gas operations, and the enhancement ratio of fluxes was consistent with the corresponding concentration observations. Fluxes calculated by the eddy covariance method show agreement with a mass balance approach within their combined uncertainties. In general, CH4 fluxes in the shale gas regions follow a lognormal distribution, with some deviations for relatively large fluxes (>10 μgm-2 s-1). Statistical analysis of the fluxes shows that a small number of facilities (i.e., ~10%) are responsible for up to ~40% of the total CH4 emissions in the two regions. We show that the airborne eddy covariance method can also be applied in some circumstances when meteorological conditions do not favor application of the mass balance method. We suggest that the airborne eddy covariance method is a reliable alternative and complementary analysis method to estimate emissions from oil and gas extraction.
- Published
- 2015
29. Effects of anthropogenic emissions on aerosol formation from isoprene and monoterpenes in the southeastern United States
- Author
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Xu, Lu, Guo, Hongyu, Boyd, Christopher M, Klein, Mitchel, Bougiatioti, Aikaterini, Cerully, Kate M, Hite, James R, Isaacman-VanWertz, Gabriel, Kreisberg, Nathan M, Knote, Christoph, Olson, Kevin, Koss, Abigail, Goldstein, Allen H, Hering, Susanne V, de Gouw, Joost, Baumann, Karsten, Lee, Shan-Hu, Nenes, Athanasios, Weber, Rodney J, and Ng, Nga Lee
- Subjects
Climate Action ,fine particulate matter ,biogenic secondary organic aerosol ,anthropogenic emissions ,sulfate ,organic nitrates - Abstract
Secondary organic aerosol (SOA) constitutes a substantial fraction of fine particulate matter and has important impacts on climate and human health. The extent to which human activities alter SOA formation from biogenic emissions in the atmosphere is largely undetermined. Here, we present direct observational evidence on the magnitude of anthropogenic influence on biogenic SOA formation based on comprehensive ambient measurements in the southeastern United States (US). Multiple high-time-resolution mass spectrometry organic aerosol measurements were made during different seasons at various locations, including urban and rural sites in the greater Atlanta area and Centreville in rural Alabama. Our results provide a quantitative understanding of the roles of anthropogenic SO2 and NOx in ambient SOA formation. We show that isoprene-derived SOA is directly mediated by the abundance of sulfate, instead of the particle water content and/or particle acidity as suggested by prior laboratory studies. Anthropogenic NOx is shown to enhance nighttime SOA formation via nitrate radical oxidation of monoterpenes, resulting in the formation of condensable organic nitrates. Together, anthropogenic sulfate and NOx can mediate 43-70% of total measured organic aerosol (29-49% of submicron particulate matter, PM1) in the southeastern US during summer. These measurements imply that future reduction in SO2 and NOx emissions can considerably reduce the SOA burden in the southeastern US. Updating current modeling frameworks with these observational constraints will also lead to more accurate treatment of aerosol formation for regions with substantial anthropogenic-biogenic interactions and consequently improve air quality and climate simulations.
- Published
- 2015
30. Absorption of volatile organic compounds (VOCs) by polymer tubing: implications for indoor air and use as a simple gas-phase volatility separation technique.
- Author
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Morris, Melissa A., Pagonis, Demetrios, Day, Douglas A., de Gouw, Joost A., Ziemann, Paul J., and Jimenez, Jose L.
- Subjects
CONDUCTING polymers ,VOLATILE organic compounds ,SILOXANES ,TUBES ,POLYMERS ,INDOOR air quality ,ATMOSPHERIC chemistry - Abstract
Previous studies have demonstrated volatility-dependent absorption of gas-phase volatile organic compounds (VOCs) to Teflon and other polymers. Polymer–VOC interactions are relevant for atmospheric chemistry sampling, as gas–wall partitioning in polymer tubing can cause delays and biases during measurements. They are also relevant to the study of indoor chemistry, where polymer-based materials are abundant (e.g., carpets and paints). In this work, we quantify the absorptive capacities of multiple tubing materials, including four nonconductive polymers (important for gas sampling and indoor air quality), four electrically conductive polymers and two commercial steel coatings (for gas and particle sampling). We compare their performance to previously characterized materials. To quantify the absorptive capacities, we expose the tubing to a series of ketones in the volatility range 104 – 109 µgm-3 and monitor transmission. For slow-diffusion polymers (e.g., perfluoroalkoxy alkane (PFA) Teflon and nylon), absorption is limited to a thin surface layer, and a single-layer absorption model can fit the data well. For fast-diffusion polymers (e.g., polyethylene and conductive silicone), a larger depth of the polymer is available for diffusion, and a multilayer absorption model is needed. The multilayer model allows fitting solid-phase diffusion coefficients for different materials, which range from 4×10-9 to 4×10-7 cm 2 s -1. These diffusion coefficients are ∼ 8 orders of magnitude larger than literature values for fluorinated ethylene propylene (FEP) Teflon film. This enormous difference explains the differences in VOC absorption measured here. We fit an equivalent absorptive mass (CW , µgm-3) for each absorptive material. We found PFA to be the least absorptive, with CW ∼ 105 µgm-3 , and conductive silicone to be the most absorptive, with CW ∼ 1013 µgm-3. PFA transmits VOCs easily and intermediate-volatility species (IVOCs) with quantifiable delays. In contrast, conductive silicone tubing transmits only the most volatile VOCs, denuding all lower-volatility species. Semi-volatile species (SVOCs) are very difficult to sample quantitatively through any tubing material. We demonstrate a system combining several slow- and fast-diffusion tubing materials that can be used to separate a mixture of VOCs into volatility classes. New conductive silicone tubing contaminated the gas stream with siloxanes, but this effect was reduced 10 000-fold for aged tubing, while maintaining the same absorptive properties. SilcoNert (tested in this work) and Silonite (tested in previous work) steel coatings showed gas transmission that was almost as good as PFA, but since they undergo adsorption, their delay times may be humidity- and concentration-dependent. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
31. Supplementary material to "Absorption of VOCs by polymer tubing: implications for indoor air and use as a simple gas-phase volatility separation technique"
- Author
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Morris, Melissa A., primary, Pagonis, Demetrios, additional, Day, Douglas A., additional, de Gouw, Joost A., additional, Ziemann, Paul J., additional, and Jimenez, Jose L., additional
- Published
- 2023
- Full Text
- View/download PDF
32. Absorption of VOCs by polymer tubing: implications for indoor air and use as a simple gas-phase volatility separation technique
- Author
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Morris, Melissa A., primary, Pagonis, Demetrios, additional, Day, Douglas A., additional, de Gouw, Joost A., additional, Ziemann, Paul J., additional, and Jimenez, Jose L., additional
- Published
- 2023
- Full Text
- View/download PDF
33. Evolution of organic carbon in the laboratory oxidation of biomass-burning emissions
- Author
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Nihill, Kevin J., primary, Coggon, Matthew M., additional, Lim, Christopher Y., additional, Koss, Abigail R., additional, Yuan, Bin, additional, Krechmer, Jordan E., additional, Sekimoto, Kanako, additional, Jimenez, Jose L., additional, de Gouw, Joost, additional, Cappa, Christopher D., additional, Heald, Colette L., additional, Warneke, Carsten, additional, and Kroll, Jesse H., additional
- Published
- 2023
- Full Text
- View/download PDF
34. COVID‐19 Impact on the Oil and Gas Industry NO2 Emissions: A Case Study of the Permian Basin
- Author
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Serrano‐Calvo, Raquel, primary, Veefkind, J. Pepijn, additional, Dix, Barbara, additional, de Gouw, Joost, additional, and Levelt, Pieternel F., additional
- Published
- 2023
- Full Text
- View/download PDF
35. SYNTHESIS OF THE SOUTHEAST ATMOSPHERE STUDIES : Investigating Fundamental Atmospheric Chemistry Questions
- Author
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Carlton, Annmarie G., de Gouw, Joost, Jimenez, Jose L., Ambrose, Jesse L., Attwood, Alexis R., Brown, Steven, Baker, Kirk R., Brock, Charles, Cohen, Ronald C., Edgerton, Sylvia, Farkas, Caroline M., Farmer, Delphine, Goldstein, Allen H., Gratz, Lynne, Guenther, Alex, Hunt, Sherri, Jaeglé, Lyatt, Jaffe, Daniel A., Mak, John, McClure, Crystal, Nenes, Athanasios, Nguyen, Thien Khoi, Pierce, Jeffrey R., de Sa, Suzane, Selin, Noelle E., Shah, Viral, Shaw, Stephanie, Shepson, Paul B., Song, Shaojie, Stutz, Jochen, Surratt, Jason D., Turpin, Barbara J., Warneke, Carsten, Washenfelder, Rebecca A., Wennberg, Paul O., and Zhou, Xianling
- Published
- 2018
36. Volatile chemical products emerging as largest petrochemical source of urban organic emissions
- Author
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McDonald, Brian C., de Gouw, Joost A., Gilman, Jessica B., Jathar, Shantanu H., Akherati, Ali, Cappa, Christopher D., Jimenez, Jose L., Lee-Taylor, Julia, Hayes, Patrick L., McKeen, Stuart A., Cui, Yu Yan, Kim, Si-Wan, Gentner, Drew R., Isaacman-VanWertz, Gabriel, Goldstein, Allen H., Harley, Robert A., Frost, Gregory J., Roberts, James M., Ryerson, Thomas B., and Trainer, Michael
- Published
- 2018
37. Biological cycling of volatile organic carbon by phytoplankton and bacterioplankton
- Author
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Halsey, Kimberly H., Giovannoni, Stephen J., Graus, Martin, Zhao, Yanlin, Landry, Zachary, Thrash, J. Cameron, Vergin, Kevin L., and de Gouw, Joost
- Published
- 2017
38. Laboratory investigations of Titan haze formation: In situ measurement of gas and particle composition
- Author
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Hörst, Sarah M., Yoon, Y. Heidi, Ugelow, Melissa S., Parker, Alex H., Li, Rui, de Gouw, Joost A., and Tolbert, Margaret A.
- Published
- 2018
- Full Text
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39. Understanding the role of the ground surface in HONO vertical structure: High resolution vertical profiles during NACHTT‐11
- Author
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VandenBoer, Trevor C, Brown, Steven S, Murphy, Jennifer G, Keene, William C, Young, Cora J, Pszenny, AAP, Kim, S, Warneke, Carsten, de Gouw, Joost A, Maben, John R, Wagner, Nicholas L, Riedel, Theran P, Thornton, Joel A, Wolfe, Daniel E, Dubé, William P, Öztürk, Fatma, Brock, Charles A, Grossberg, Nicole, Lefer, Barry, Lerner, Brian, Middlebrook, Ann M, and Roberts, James M
- Subjects
Earth Sciences ,Atmospheric Sciences ,Physical Geography and Environmental Geoscience ,Atmospheric sciences ,Climate change science - Abstract
A negative-ion proton-transfer chemical ionization mass spectrometer was deployed on a mobile tower-mounted platform during Nitrogen, Aerosol Composition, and Halogens on a Tall Tower (NACHTT) to measure nitrous acid (HONO) in the winter of 2011. High resolution vertical profiles revealed (i) HONO gradients in nocturnal boundary layers, (ii) ground surface dominates HONO production by heterogeneous uptake of NO2, (iii) significant quantities of HONO may be deposited to the ground surface at night, (iv) daytime gradients indicative of ground HONO production or emission, and (v) an estimated surface HONO reservoir comparable or larger than integrated daytime HONO surface production. Nocturnal integrated column observations of HONO and NO2 allowed direct evaluation of nocturnal ground surface uptake coefficients for these species (γNO2, surf = 2 × 10 -6 to 1.6 × 10-5 and γHONO, surf = 2 × 10-5 to 2 × 10-4). A chemical model showed that the unknown source of HONO was highest in the morning, 4 × 10 6 molecules cm-3 s-1 (600 pptv h-1), declined throughout the day, and minimized near 1 × 106 molecules cm-3 s-1 (165 pptv h-1). The quantity of surface-deposited HONO was also modeled, showing that HONO deposited to the surface at night was at least 25%, and likely in excess of 100%, of the calculated unknown daytime HONO source. These results suggest that if nocturnally deposited HONO forms a conservative surface reservoir, which can be released the following day, a significant fraction of the daytime HONO source can be explained for the NACHTT observations. Key Points HONO vertical gradients form on nights with stable nocturnal boundary layersNocturnal HONO production consistent with ground surface area dominanceSurface deposition of HONO may be a reservoir for the unknown daytime source ©2013. American Geophysical Union. All Rights Reserved.
- Published
- 2013
40. A Library of Proton-Transfer Reactions of H3O+ Ions Used for Trace Gas Detection
- Author
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Pagonis, Demetrios, Sekimoto, Kanako, and de Gouw, Joost
- Published
- 2019
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41. Chemical data quantify Deepwater Horizon hydrocarbon flow rate and environmental distribution
- Author
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Ryerson, Thomas B, Camilli, Richard, Kessler, John D, Kujawinski, Elizabeth B, Reddy, Christopher M, Valentine, David L, Atlas, Elliot, Blake, Donald R, de Gouw, Joost, Meinardi, Simone, Parrish, David D, Peischl, Jeff, Seewald, Jeffrey S, and Warneke, Carsten
- Subjects
Earth Sciences ,Geochemistry ,Gulf of Mexico ,deepwater blowout ,marine hydrocarbon partitioning ,oil spill flow rate - Abstract
Detailed airborne, surface, and subsurface chemical measurements, primarily obtained in May and June 2010, are used to quantify initial hydrocarbon compositions along different transport pathways (i.e., in deep subsurface plumes, in the initial surface slick, and in the atmosphere) during the Deepwater Horizon oil spill. Atmospheric measurements are consistent with a limited area of surfacing oil, with implications for leaked hydrocarbon mass transport and oil drop size distributions. The chemical data further suggest relatively little variation in leaking hydrocarbon composition over time. Although readily soluble hydrocarbons made up ∼25% of the leaking mixture by mass, subsurface chemical data show these compounds made up ∼69% of the deep plume mass; only ∼31% of the deep plume mass was initially transported in the form of trapped oil droplets. Mass flows along individual transport pathways are also derived from atmospheric and subsurface chemical data. Subsurface hydrocarbon composition, dissolved oxygen, and dispersant data are used to assess release of hydrocarbons from the leaking well. We use the chemical measurements to estimate that (7.8 ± 1.9) × 10(6) kg of hydrocarbons leaked on June 10, 2010, directly accounting for roughly three-quarters of the total leaked mass on that day. The average environmental release rate of (10.1 ± 2.0) × 10(6) kg/d derived using atmospheric and subsurface chemical data agrees within uncertainties with the official average leak rate of (10.2 ± 1.0) × 10(6) kg/d derived using physical and optical methods.
- Published
- 2012
42. Multiyear trends in volatile organic compounds in Los Angeles, California: Five decades of decreasing emissions
- Author
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Warneke, Carsten, de Gouw, Joost A, Holloway, John S, Peischl, Jeff, Ryerson, Thomas B, Atlas, Elliot, Blake, Don, Trainer, Michael, and Parrish, David D
- Subjects
Meteorology & Atmospheric Sciences - Published
- 2012
43. Organosulfates as Tracers for Secondary Organic Aerosol (SOA) Formation from 2‑Methyl-3-Buten-2-ol (MBO) in the Atmosphere
- Author
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Zhang, Haofei, Worton, David R, Lewandowski, Michael, Ortega, John, Rubitschun, Caitlin L, Park, Jeong-Hoo, Kristensen, Kasper, Campuzano-Jost, Pedro, Day, Douglas A, Jimenez, Jose L, Jaoui, Mohammed, Offenberg, John H, Kleindienst, Tadeusz E, Gilman, Jessica, Kuster, William C, de Gouw, Joost, Park, Changhyoun, Schade, Gunnar W, Frossard, Amanda A, Russell, Lynn, Kaser, Lisa, Jud, Werner, Hansel, Armin, Cappellin, Luca, Karl, Thomas, Glasius, Marianne, Guenther, Alex, Goldstein, Allen H, Seinfeld, John H, Gold, Avram, Kamens, Richard M, and Surratt, Jason D
- Subjects
Earth Sciences ,Atmospheric Sciences ,Aerosols ,Air Pollutants ,Atmosphere ,Hydroxyl Radical ,Nitric Oxide ,Oxidants ,Photochemical ,Oxidation-Reduction ,Pentanols ,Pinus ,Sulfuric Acid Esters ,Volatile Organic Compounds ,Environmental Sciences - Abstract
2-Methyl-3-buten-2-ol (MBO) is an important biogenic volatile organic compound (BVOC) emitted by pine trees and a potential precursor of atmospheric secondary organic aerosol (SOA) in forested regions. In the present study, hydroxyl radical (OH)-initiated oxidation of MBO was examined in smog chambers under varied initial nitric oxide (NO) and aerosol acidity levels. Results indicate measurable SOA from MBO under low-NO conditions. Moreover, increasing aerosol acidity was found to enhance MBO SOA. Chemical characterization of laboratory-generated MBO SOA reveals that an organosulfate species (C(5)H(12)O(6)S, MW 200) formed and was substantially enhanced with elevated aerosol acidity. Ambient fine aerosol (PM(2.5)) samples collected from the BEARPEX campaign during 2007 and 2009, as well as from the BEACHON-RoMBAS campaign during 2011, were also analyzed. The MBO-derived organosulfate characterized from laboratory-generated aerosol was observed in PM(2.5) collected from these campaigns, demonstrating that it is a molecular tracer for MBO-initiated SOA in the atmosphere. Furthermore, mass concentrations of the MBO-derived organosulfate are well correlated with MBO mixing ratio, temperature, and acidity in the field campaigns. Importantly, this compound accounted for an average of 0.25% and as high as 1% of the total organic aerosol mass during BEARPEX 2009. An epoxide intermediate generated under low-NO conditions is tentatively proposed to produce MBO SOA.
- Published
- 2012
44. Automated single-ion peak fitting as an efficient approach for analyzing complex chromatographic data
- Author
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Isaacman-VanWertz, Gabriel, Sueper, Donna T., Aikin, Kenneth C., Lerner, Brian M., Gilman, Jessica B., de Gouw, Joost A., Worsnop, Douglas R., and Goldstein, Allen H.
- Published
- 2017
- Full Text
- View/download PDF
45. Calculation of the sensitivity of proton-transfer-reaction mass spectrometry (PTR-MS) for organic trace gases using molecular properties
- Author
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Sekimoto, Kanako, Li, Shao-Meng, Yuan, Bin, Koss, Abigail, Coggon, Matthew, Warneke, Carsten, and de Gouw, Joost
- Published
- 2017
- Full Text
- View/download PDF
46. Cloud droplets aid the production of formic acid in the atmosphere
- Author
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de Gouw, Joost and Farmer, Delphine
- Published
- 2021
- Full Text
- View/download PDF
47. Measurements of VOCs in ambient air by Vocus PTR-TOF-MS: calibrations, instrument background corrections, and introducing a PTR Data Toolkit
- Author
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Jensen, Andrew R., primary, Koss, Abigail R., additional, Hales, Ryder B., additional, and de Gouw, Joost A., additional
- Published
- 2023
- Full Text
- View/download PDF
48. Significant Production of Ozone from Germicidal UV Lights at 222 nm
- Author
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Peng, Zhe, primary, Day, Douglas A., additional, Symonds, Guy, additional, Jenks, Olivia, additional, Stark, Harald, additional, Handschy, Anne V., additional, de Gouw, Joost, additional, and Jimenez, Jose L., additional
- Published
- 2023
- Full Text
- View/download PDF
49. Investigation of Gas-Phase Products from the NO3 Radical Oxidation of Δ-3-Carene
- Author
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Jenks, Olivia J., primary, DeVault, Marla P., additional, Ziola, Anna C., additional, Morris, Melissa A., additional, Schueneman, Melinda K., additional, Stark, Harald, additional, Jimenez, Jose L., additional, Ziemann, Paul J., additional, and de Gouw, Joost A., additional
- Published
- 2023
- Full Text
- View/download PDF
50. Multi-day photochemical evolution of organic aerosol from biomass burning emissionsElectronic supplementary information (ESI) available: Summary of environmental chamber data, additional SOM-TOMAS results and comparisons with measurements, and sensitivity simulation results. See DOI: https://doi.org/10.1039/d3ea00111c
- Author
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Dearden, Abraham, He, Yicong, Akherati, Ali, Lim, Christopher Y., Coggon, Matthew M., Koss, Abigail R., de Gouw, Joost, Warneke, Carsten, Yee, Lindsay D., Seinfeld, John H., Cappa, Christopher D., Kroll, Jesse H., Pierce, Jeffrey R., and Jathar, Shantanu H.
- Abstract
Biomass burning is an important source of primary and secondary organic aerosol (POA, SOA, and together, OA) to the atmosphere. The photochemical evolution of biomass burning OA, especially over long photochemical ages, is highly complex and there are large uncertainties in how this evolution is represented in models. Recently, Lim et al.(2019) performed and reported on photooxidation experiments of biomass burning emissions using a small environmental chamber (∼150 L) to study the OA evolution over multiple equivalent days of photochemical aging. In this work, we use a kinetic, process-level model (SOM-TOMAS; Statistical Oxidation Model-TwO Moment Aerosol Sectional) to simulate the photochemical evolution of OA in 18 chamber experiments performed on emissions from 10 different fuels. A base version of the model was able to simulate the time-dependent evolution of the OA mass concentration and its oxygen-to-carbon ratio (O : C) at short photochemical ages (0.5 to 1 equivalent days). At longer photochemical ages (>1 equivalent day), the model exhibited poor skill in predicting the OA mass concentration and significantly underestimated the OA O : C. The modeled OA after several equivalent days of photochemical aging was slightly dominated by SOA (average of 57% across all experiments) with the remainder being POA (average of 43% across all experiments). Semi-volatile organic compounds, oxygenated aromatics, and heterocyclics accounted for the majority (89%, on average) of the SOA formed. Experimental artifacts (i.e., particle and vapor wall losses) were found to be much more important in influencing the OA evolution than other processes (i.e., dilution, heterogeneous chemistry, and oligomerization reactions). Adjustments to the kinetic model seemed to improve model performance only marginally indicating that the model was missing precursors, chemical pathways, or both, especially to explain the observed enhancement in OA mass and O : C over longer photochemical ages. While far from ideal, this work contributes to a process-level understanding of biomass burning OA that is relevant for its extended evolution at regional and global scales.
- Published
- 2024
- Full Text
- View/download PDF
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