Articles | Volume 8, issue 7
Research article 08 Jul 2015
Research article | 08 Jul 2015
Efficient photochemical generation of peroxycarboxylic nitric anhydrides with ultraviolet light-emitting diodes
N. D. Rider et al.
No articles found.
Debora Griffin, Chris A. McLinden, Enrico Dammers, Cristen Adams, Chelsea E. Stockwell, Carsten Warneke, Ilann Bourgeois, Jeff Peischl, Thomas B. Ryerson, Kyle J. Zarzana, Jake P. Rowe, Rainer Volkamer, Christoph Knote, Natalie Kille, Theodore K. Koenig, Christopher F. Lee, Drew Rollins, Pamela S. Rickly, Jack Chen, Lukas Fehr, Adam Bourassa, Doug Degenstein, Katherine Hayden, Cristian Mihele, Sumi N. Wren, John Liggio, Ayodeji Akingunola, and Paul Makar
Atmos. Meas. Tech., 14, 7929–7957,Short summary
Satellite-derived NOx emissions from biomass burning are estimated with TROPOMI observations. Two common emission estimation methods are applied, and sensitivity tests with model output were performed to determine the accuracy of these methods. The effect of smoke aerosols on TROPOMI NO2 columns is estimated and compared to aircraft observations from four different aircraft campaigns measuring biomass burning plumes in 2018 and 2019 in North America.
Chong Han, Hongxing Yang, Kun Li, Patrick Lee, John Liggio, Amy Leithead, and Shao-Meng Li
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
We presented yields and compositions of Si-containing SOA generated from the reaction of cVMS (D3-D6) with OH radicals. NOx played negative roles on cVMS SOA formation, while ammonium sulfate seeds enhanced D3-D5 SOA yields at short photochemical ages under high-NOx conditions. The aerosol mass spectra confirmed that the components of cVMS SOA significantly relied on OH exposure. A global cVMS-derived SOA source strength was estimated to understand SOA formation potentials of cVMS.
Sepehr Fathi, Mark Gordon, Paul A. Makar, Ayodeji Akingunola, Andrea Darlington, John Liggio, Katherine Hayden, and Shao-Meng Li
Atmos. Chem. Phys., 21, 15461–15491,Short summary
We have investigated the accuracy of aircraft-based mass balance methodologies through computer model simulations of the atmosphere and air quality at a regional high-resolution scale. We have defined new quantitative metrics to reduce emission retrieval uncertainty by evaluating top-down mass balance estimates against the known simulated meteorology and input emissions. We also recommend methodologies and flight strategies for improved retrievals in future aircraft-based studies.
Konstantin Baibakov, Samuel LeBlanc, Keyvan Ranjbar, Norman T. O'Neill, Mengistu Wolde, Jens Redemann, Kristina Pistone, Shao-Meng Li, John Liggio, Katherine Hayden, Tak W. Chan, Michael J. Wheeler, Leonid Nichman, Connor Flynn, and Roy Johnson
Atmos. Chem. Phys., 21, 10671–10687,Short summary
We find that the airborne measurements of the vertical extinction due to aerosols (aerosol optical depth, AOD) obtained in the Athabasca Oil Sands Region (AOSR) can significantly exceed ground-based values. This can have an effect on estimating the AOSR radiative impact and is relevant to satellite validation based on ground-based measurements. We also show that the AOD can marginally increase as the plumes are being transported away from the source and the new particles are being formed.
Katherine Hayden, Shao-Meng Li, Paul Makar, John Liggio, Samar G. Moussa, Ayodeji Akingunola, Robert McLaren, Ralf M. Staebler, Andrea Darlington, Jason O'Brien, Junhua Zhang, Mengistu Wolde, and Leiming Zhang
Atmos. Chem. Phys., 21, 8377–8392,Short summary
We developed a method using aircraft measurements to determine lifetimes with respect to dry deposition for oxidized sulfur and nitrogen compounds over the boreal forest in Alberta, Canada. Atmospheric lifetimes were significantly shorter than derived from chemical transport models with differences related to modelled dry deposition velocities. The shorter lifetimes suggest models need to reassess dry deposition treatment and predictions of sulfur and nitrogen in the atmosphere and ecosystems.
Jenna C. Ditto, Megan He, Tori N. Hass-Mitchell, Samar G. Moussa, Katherine Hayden, Shao-Meng Li, John Liggio, Amy Leithead, Patrick Lee, Michael J. Wheeler, Jeremy J. B. Wentzell, and Drew R. Gentner
Atmos. Chem. Phys., 21, 255–267,Short summary
Forest fires are an important source of reactive organic gases and aerosols to the atmosphere. We analyzed organic aerosols collected from an aircraft above a boreal forest fire and reported an increasing contribution from compounds containing oxygen, nitrogen, and sulfur as the plume aged, with sulfide and ring-bound nitrogen functionality. Our results demonstrated chemistry that is important in biomass burning but also in urban/developing regions with high local nitrogen and sulfur emissions.
Nicholas J. Gingerysty and Hans D. Osthoff
Atmos. Meas. Tech., 13, 4159–4167,Short summary
The generation of clean calibration gases is critical for accurate ambient air measurements. Here, we describe a source of HONO vapour dynamically generated from reaction of HCl and NaNO2. The output was characterized by Fourier transform infrared (FTIR) and thermal-dissociation cavity ring-down spectroscopy (TD-CRDS) and was stable, tuneable, and > 95 % pure. We show how generation of unwanted side products (NO, NO2, and ClNO) can be avoided.
Zoë Y. W. Davis, Udo Frieß, Kevin B. Strawbridge, Monika Aggarwaal, Sabour Baray, Elijah G. Schnitzler, Akshay Lobo, Vitali E. Fioletov, Ihab Abboud, Chris A. McLinden, Jim Whiteway, Megan D. Willis, Alex K. Y. Lee, Jeff Brook, Jason Olfert, Jason O'Brien, Ralf Staebler, Hans D. Osthoff, Cristian Mihele, and Robert McLaren
Atmos. Meas. Tech., 13, 1129–1155,Short summary
Here, we evaluate a ground-based remote sensing method (MAX-DOAS) for measuring total pollutant loading and vertical profiles of pollution in the lower atmosphere by comparing our method to a variety of other measurement methods (lidar, sunphotometer, active DOAS, and aircraft measurements). Measurements were made in the Athabasca Oil Sands Region in Alberta, Canada. The complex dataset provided a rare opportunity to evaluate the performance of MAX-DOAS under varying atmospheric conditions.
Nick Jordan and Hans D. Osthoff
Atmos. Meas. Tech., 13, 273–285,Short summary
We describe a new spectrometer for quantification of HONO and NO2 in ambient air, called HODOR. The instrument uses an LED and two highly reflective mirrors to increase the effective optical absorption path to ~6 km. The accuracy of concentration retrievals was validated using parallel measurements by a single wavelength cavity ring-down spectrometer of laboratory-generated gas mixtures. The instrument's precision suffices for quantification of HONO and NO2 in an urban environment.
Alex K. Y. Lee, Max G. Adam, John Liggio, Shao-Meng Li, Kun Li, Megan D. Willis, Jonathan P. D. Abbatt, Travis W. Tokarek, Charles A. Odame-Ankrah, Hans D. Osthoff, Kevin Strawbridge, and Jeffery R. Brook
Atmos. Chem. Phys., 19, 12209–12219,Short summary
This work provides the first direct field evidence that anthropogenic organo-nitrate contributed up to half of secondary organic aerosol (SOA) mass that was freshly produced within the emission plumes of oil sands facilities in Alberta, Canada. The findings illustrate the central role of organo-nitrate in SOA production from the oil and gas industry, with relevance for other urban and industrial regions with significant intermediate-volatility organic compounds (IVOCs) and NOx emissions.
Kun Li, John Liggio, Patrick Lee, Chong Han, Qifan Liu, and Shao-Meng Li
Atmos. Chem. Phys., 19, 9715–9731,Short summary
A new oxidation flow reactor was developed and applied to study the secondary organic aerosol (SOA) formation from precursors associated with oil-sands (OS) operations. The results reveal that the SOA yields from OS precursors are related to the volatilities of precursors and that open-pit mining is the main source of SOA formed from oil sands. In addition, cyclic alkanes are found to play an important role in SOA formation from oil-sands precursors.
Jonathan P. D. Abbatt, W. Richard Leaitch, Amir A. Aliabadi, Allan K. Bertram, Jean-Pierre Blanchet, Aude Boivin-Rioux, Heiko Bozem, Julia Burkart, Rachel Y. W. Chang, Joannie Charette, Jai P. Chaubey, Robert J. Christensen, Ana Cirisan, Douglas B. Collins, Betty Croft, Joelle Dionne, Greg J. Evans, Christopher G. Fletcher, Martí Galí, Roghayeh Ghahremaninezhad, Eric Girard, Wanmin Gong, Michel Gosselin, Margaux Gourdal, Sarah J. Hanna, Hakase Hayashida, Andreas B. Herber, Sareh Hesaraki, Peter Hoor, Lin Huang, Rachel Hussherr, Victoria E. Irish, Setigui A. Keita, John K. Kodros, Franziska Köllner, Felicia Kolonjari, Daniel Kunkel, Luis A. Ladino, Kathy Law, Maurice Levasseur, Quentin Libois, John Liggio, Martine Lizotte, Katrina M. Macdonald, Rashed Mahmood, Randall V. Martin, Ryan H. Mason, Lisa A. Miller, Alexander Moravek, Eric Mortenson, Emma L. Mungall, Jennifer G. Murphy, Maryam Namazi, Ann-Lise Norman, Norman T. O'Neill, Jeffrey R. Pierce, Lynn M. Russell, Johannes Schneider, Hannes Schulz, Sangeeta Sharma, Meng Si, Ralf M. Staebler, Nadja S. Steiner, Jennie L. Thomas, Knut von Salzen, Jeremy J. B. Wentzell, Megan D. Willis, Gregory R. Wentworth, Jun-Wei Xu, and Jacqueline D. Yakobi-Hancock
Atmos. Chem. Phys., 19, 2527–2560,Short summary
The Arctic is experiencing considerable environmental change with climate warming, illustrated by the dramatic decrease in sea-ice extent. It is important to understand both the natural and perturbed Arctic systems to gain a better understanding of how they will change in the future. This paper summarizes new insights into the relationships between Arctic aerosol particles and climate, as learned over the past five or so years by a large Canadian research consortium, NETCARE.
Nick Jordan, Connie Z. Ye, Satyaki Ghosh, Rebecca A. Washenfelder, Steven S. Brown, and Hans D. Osthoff
Atmos. Meas. Tech., 12, 1277–1293,Short summary
A new spectrometer to measure abundances of the atmospheric trace gases nitrogen dioxide and iodine is described. The spectrometer uses a light-emitting diode between 470 and 540 nm and two highly reflective mirrors to yield an effective absorption path of 6.3 km. We remeasured scattering cross sections of common atmospheric gases in the cyan region and present sample NO2 measurements that agreed with those made with a laser-based instrument.
Travis W. Tokarek, Charles A. Odame-Ankrah, Jennifer A. Huo, Robert McLaren, Alex K. Y. Lee, Max G. Adam, Megan D. Willis, Jonathan P. D. Abbatt, Cristian Mihele, Andrea Darlington, Richard L. Mittermeier, Kevin Strawbridge, Katherine L. Hayden, Jason S. Olfert, Elijah G. Schnitzler, Duncan K. Brownsey, Faisal V. Assad, Gregory R. Wentworth, Alex G. Tevlin, Douglas E. J. Worthy, Shao-Meng Li, John Liggio, Jeffrey R. Brook, and Hans D. Osthoff
Atmos. Chem. Phys., 18, 17819–17841,Short summary
Measurements of air pollutants at a ground site near Fort McKay in the Athabasca oil sands region in the summer of 2013 are presented. A large number of intermediate-volatility organic compounds (IVOCs) were observed; these molecules were shown previously to generate atmospheric particles downwind of the region. A principal component analysis was performed to identify major pollution source types, including which source(s) is(are) associated with IVOC emissions (e.g., freshly mined bitumen).
Sumi N. Wren, John Liggio, Yuemei Han, Katherine Hayden, Gang Lu, Cris M. Mihele, Richard L. Mittermeier, Craig Stroud, Jeremy J. B. Wentzell, and Jeffrey R. Brook
Atmos. Chem. Phys., 18, 16979–17001,Short summary
We made measurements from a mobile laboratory across a large urban area and determined fleet-average vehicle emission factors (EFs) for a suite of traffic-related air pollutants. We present the first real-world EFs for isocyanic acid (HNCO) and hydrogen cyanide (HCN) and insight into their on-road variability. We find that vehicles may represent an important source of these air toxics at an urban scale. This work has implications for understanding population exposure to these species.
Emma L. Mungall, Jonathan P. D. Abbatt, Jeremy J. B. Wentzell, Gregory R. Wentworth, Jennifer G. Murphy, Daniel Kunkel, Ellen Gute, David W. Tarasick, Sangeeta Sharma, Christopher J. Cox, Taneil Uttal, and John Liggio
Atmos. Chem. Phys., 18, 10237–10254,Short summary
We measured gas-phase formic and acetic acid at Alert, Nunavut. These acids play an important role in cloud water acidity in remote environments, yet they are not well represented in chemical transport models, particularly in the Arctic. We observed high levels of formic and acetic acid under both cold, wet, and cloudy and warm, sunny, and dry conditions, suggesting that multiple sources significantly contribute to gas-phase concentrations of these species in the summer Arctic.
Youssef M. Taha, Matthew T. Saowapon, Faisal V. Assad, Connie Z. Ye, Xining Chen, Natasha M. Garner, and Hans D. Osthoff
Atmos. Meas. Tech., 11, 4109–4127,Short summary
Nitrogen oxides are commonly measured by selective thermal dissociation (TD) to NO2, which can be quantified by optical absorption. Quantification of peroxynitrates (RO2NO2) by TD methods, however, is challenging in ambient air since NO2 is usually more abundant than RO2NO2. Here, a method to boost the sensitivity of TD instruments by chemical amplification following addition of ~ 1 % ethane and ~ 1 ppm NO to the inlet is presented. Advantages and disadvantages of the new method are discussed.
Neda Amiri, Roghayeh Ghahremaninezhad, Ofelia Rempillo, Travis W. Tokarek, Charles A. Odame-Ankrah, Hans D. Osthoff, and Ann-Lise Norman
Atmos. Chem. Phys., 18, 7757–7780,
Hans D. Osthoff, Charles A. Odame-Ankrah, Youssef M. Taha, Travis W. Tokarek, Corinne L. Schiller, Donna Haga, Keith Jones, and Roxanne Vingarzan
Atmos. Chem. Phys., 18, 6293–6315,Short summary
The nocturnal nitrogen oxides dinitrogen pentoxide (N2O5) and its heterogeneous uptake product nitryl chloride (ClNO2) can have profound impacts on air quality, yet their abundances and chemistry are only sparsely constrained by field measurements. Here, we present the first measurements of N2O5 and ClNO2 in the Lower Fraser Valley of British Columbia, Canada. Concentrations were lower than have been observed elsewhere. Morning peaks indicate higher ClNO2 production above the measurement site.
John Liggio, Samar G. Moussa, Jeremy Wentzell, Andrea Darlington, Peter Liu, Amy Leithead, Katherine Hayden, Jason O'Brien, Richard L. Mittermeier, Ralf Staebler, Mengistu Wolde, and Shao-Meng Li
Atmos. Chem. Phys., 17, 8411–8427,Short summary
The emission and formation of gaseous organic acids from the oil sands industry in Canada is explored through aircraft measurements directly over and downwind wind of industrial facilities. Results demonstrated that the formation of organic acids through atmospheric chemical reactions dominated over the direct emissions from mining activities but could not be explicitly modeled. The results highlight the need for improved understanding of photochemical mechanisms leading to these species.
Nga Lee Ng, Steven S. Brown, Alexander T. Archibald, Elliot Atlas, Ronald C. Cohen, John N. Crowley, Douglas A. Day, Neil M. Donahue, Juliane L. Fry, Hendrik Fuchs, Robert J. Griffin, Marcelo I. Guzman, Hartmut Herrmann, Alma Hodzic, Yoshiteru Iinuma, José L. Jimenez, Astrid Kiendler-Scharr, Ben H. Lee, Deborah J. Luecken, Jingqiu Mao, Robert McLaren, Anke Mutzel, Hans D. Osthoff, Bin Ouyang, Benedicte Picquet-Varrault, Ulrich Platt, Havala O. T. Pye, Yinon Rudich, Rebecca H. Schwantes, Manabu Shiraiwa, Jochen Stutz, Joel A. Thornton, Andreas Tilgner, Brent J. Williams, and Rahul A. Zaveri
Atmos. Chem. Phys., 17, 2103–2162,Short summary
Oxidation of biogenic volatile organic compounds by NO3 is an important interaction between anthropogenic and natural emissions. This review results from a June 2015 workshop and includes the recent literature on kinetics, mechanisms, organic aerosol yields, and heterogeneous chemistry; advances in analytical instrumentation; the current state NO3-BVOC chemistry in atmospheric models; and critical needs for future research in modeling, field observations, and laboratory studies.
Brian M. Lerner, Jessica B. Gilman, Kenneth C. Aikin, Elliot L. Atlas, Paul D. Goldan, Martin Graus, Roger Hendershot, Gabriel A. Isaacman-VanWertz, Abigail Koss, William C. Kuster, Richard A. Lueb, Richard J. McLaughlin, Jeff Peischl, Donna Sueper, Thomas B. Ryerson, Travis W. Tokarek, Carsten Warneke, Bin Yuan, and Joost A. de Gouw
Atmos. Meas. Tech., 10, 291–313,Short summary
Whole air sampling followed by analysis by gas chromatography is a common technique for characterization of trace volatile organic compounds in the atmosphere. We describe a new automated gas chromatograph–mass spectrograph which uses a Stirling cooler for sample preconcentration at −165 °C without the need for a cryogen such as liquid nitrogen. We also discuss potential sources of artifacts from our electropolished stainless steel sampling system and present results from two field campaigns.
Yuemei Han, Craig A. Stroud, John Liggio, and Shao-Meng Li
Atmos. Chem. Phys., 16, 13929–13944,Short summary
This study investigates the acidity effect on the yield and chemical composition of α-pinene secondary organic aerosol based on a series of laboratory experiments performed using a photochemical reaction chamber under high- and low-NOx conditions. We have found that the acidity effect largely depends on NOx level and the inorganic acidity has a significant role to play in determining various organic aerosol chemical properties such as mass yields, oxidation state, and organic nitrate content.
Maria Zatko, Joseph Erbland, Joel Savarino, Lei Geng, Lauren Easley, Andrew Schauer, Timothy Bates, Patricia K. Quinn, Bonnie Light, David Morison, Hans D. Osthoff, Seth Lyman, William Neff, Bin Yuan, and Becky Alexander
Atmos. Chem. Phys., 16, 13837–13851,Short summary
This manuscript presents chemical and optical observations collected in the air and snow during UBWOS2014 in eastern Utah. These observations are used to calculate fluxes of reactive nitrogen associated with snow nitrate photolysis. Snow-sourced reactive nitrogen fluxes are compared to reactive nitrogen emission inventories to find that snow-sourced reactive nitrogen is a minor contributor to the reactive nitrogen budget, and thus wintertime ground-level ozone formation, in the Uintah Basin.
Alex K. Y. Lee, Jonathan P. D. Abbatt, W. Richard Leaitch, Shao-Meng Li, Steve J. Sjostedt, Jeremy J. B. Wentzell, John Liggio, and Anne Marie Macdonald
Atmos. Chem. Phys., 16, 6721–6733,Short summary
Substantial biogenic secondary organic aerosol (BSOA) formation was investigated in a coniferous forest mountain region in Whistler, British Columbia. A largely biogenic aerosol growth episode was observed, providing a unique opportunity to investigate BSOA formation chemistry in a forested environment. In particular, our observations provide insights into the relative importance of different oxidation mechanisms between day and night.
Emma L. Mungall, Betty Croft, Martine Lizotte, Jennie L. Thomas, Jennifer G. Murphy, Maurice Levasseur, Randall V. Martin, Jeremy J. B. Wentzell, John Liggio, and Jonathan P. D. Abbatt
Atmos. Chem. Phys., 16, 6665–6680,Short summary
Previous work has suggested that marine emissions of dimethyl sulfide (DMS) could impact the Arctic climate through interactions with clouds. We made the first high-time-resolution measurements of summertime atmospheric DMS in the Canadian Arctic, and performed source sensitivity simulations. We found that regional marine sources dominated, but do not appear to be sufficient to explain our observations. Understanding DMS sources in the Arctic is necessary to model future climate in the region.
Bin Yuan, John Liggio, Jeremy Wentzell, Shao-Meng Li, Harald Stark, James M. Roberts, Jessica Gilman, Brian Lerner, Carsten Warneke, Rui Li, Amy Leithead, Hans D. Osthoff, Robert Wild, Steven S. Brown, and Joost A. de Gouw
Atmos. Chem. Phys., 16, 2139–2153,Short summary
We describe high-resolution measurements of nitrated phenols using a time-of-flight chemical ionization mass spectrometer (ToF-CIMS). Strong diurnal profiles were observed for nitrated phenols, with concentration maxima at night. Box model simulations were able to reproduce the measured nitrated phenols.
M. W. Shephard, C. A. McLinden, K. E. Cady-Pereira, M. Luo, S. G. Moussa, A. Leithead, J. Liggio, R. M. Staebler, A. Akingunola, P. Makar, P. Lehr, J. Zhang, D. K. Henze, D. B. Millet, J. O. Bash, L. Zhu, K. C. Wells, S. L. Capps, S. Chaliyakunnel, M. Gordon, K. Hayden, J. R. Brook, M. Wolde, and S.-M. Li
Atmos. Meas. Tech., 8, 5189–5211,Short summary
This study provides direct validations of Tropospheric Emission Spectrometer (TES) satellite retrieved profiles against coincident aircraft profiles of carbon monoxide, ammonia, methanol, and formic acid, all of which are of interest for air quality. The comparisons are performed over the Canadian oil sands region during an intensive field campaign in support of the Joint Canada-Alberta Implementation Plan for the Oil Sands Monitoring (JOSM). Initial model evaluations are also provided.
Y. Liu, J. Liggio, R. Staebler, and S.-M. Li
Atmos. Chem. Phys., 15, 13569–13584,Short summary
This work for the first time demonstrated that organonitrogen compounds (NOC) can be formed efficiently via the uptake of ammonia by newly formed secondary organic aerosol using a smog chamber equipped with a HR-ToF-AMS. Based on the measured kinetics, this study suggests that light absorption by NOC in atmospheric particles may be important in regions where the BC contribution is minimal and NOC from ammonia should be considered with respect to overall deposition of nitrogen to ecosystems.
L. Huang, S. L. Gong, M. Gordon, J. Liggio, R. Staebler, C. A. Stroud, G. Lu, C. Mihele, J. R. Brook, and C. Q. Jia
Atmos. Chem. Phys., 14, 12631–12648,
Y. Liu, L. Huang, S.-M. Li, T. Harner, and J. Liggio
Atmos. Chem. Phys., 14, 12195–12207,
T. W. Tokarek, J. A. Huo, C. A. Odame-Ankrah, D. Hammoud, Y. M. Taha, and H. D. Osthoff
Atmos. Meas. Tech., 7, 3263–3283,
Y. Liu, S.-M. Li, and J. Liggio
Atmos. Chem. Phys., 14, 9201–9211,
M. Gordon, A. Vlasenko, R. M. Staebler, C. Stroud, P. A. Makar, J. Liggio, S.-M. Li, and S. Brown
Atmos. Chem. Phys., 14, 9087–9097,
C. J. Young, R. A. Washenfelder, P. M. Edwards, D. D. Parrish, J. B. Gilman, W. C. Kuster, L. H. Mielke, H. D. Osthoff, C. Tsai, O. Pikelnaya, J. Stutz, P. R. Veres, J. M. Roberts, S. Griffith, S. Dusanter, P. S. Stevens, J. Flynn, N. Grossberg, B. Lefer, J. S. Holloway, J. Peischl, T. B. Ryerson, E. L. Atlas, D. R. Blake, and S. S. Brown
Atmos. Chem. Phys., 14, 3427–3440,
L. Ahlm, K. M. Shakya, L. M. Russell, J. C. Schroder, J. P. S. Wong, S. J. Sjostedt, K. L. Hayden, J. Liggio, J. J. B. Wentzell, H. A. Wiebe, C. Mihele, W. R. Leaitch, and A. M. Macdonald
Atmos. Chem. Phys., 13, 3393–3407,
J. Liggio and S.-M. Li
Atmos. Chem. Phys., 13, 2989–3002,
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SAPHIRUse of electrochemical sensors for measurement of air pollution: correcting interference response and validating measurementsObservations of VOC emissions and photochemical products over US oil- and gas-producing regions using high-resolution H3O+ CIMS (PTR-ToF-MS)Simultaneous multicopter-based air sampling and sensing of meteorological variablesEvaluation and environmental correction of ambient CO2 measurements from a low-cost NDIR sensorA closed-chamber method to measure greenhouse gas fluxes from dry aquatic sedimentsMethods to homogenize electrochemical concentration cell (ECC) ozonesonde measurements across changes in sensing solution concentration or ozonesonde manufacturerComparison of optical-feedback cavity-enhanced absorption spectroscopy and gas chromatography for ground-based and airborne measurements of atmospheric CO concentrationA European-wide 222radon and 222radon progeny comparison study
Wengang Zhang, Ling Wang, Yang Yu, Guirong Xu, Xiuqing Hu, Zhikang Fu, and Chunguang Cui
Atmos. Meas. Tech., 14, 7821–7834,Short summary
Global precipitable water vapor (PWV) derived from MERSI-II (Medium Resolution Spectral Imager) is compared with PWV from the Integrated Global Radiosonde Archive (IGRA). Our results show a good agreement between PWV from MERSI-II and IGRA and that MERSI-II PWV is slightly underestimated on the whole, especially in summer. The bias between MERSI-II and IGRA grows with a larger spatial distance between the footprint of the satellite and the IGRA station, as well as increasing PWV.
Trevor W. Coates, Monzurul Alam, Thomas K. Flesch, and Guillermo Hernandez-Ramirez
Atmos. Meas. Tech., 14, 7147–7152,Short summary
A field study tested two footprint models for calculating surface emissions from downwind flux measurements. Emission rates from a 10 × 10 m synthetic source were estimated with the simple Kormann–Meixner model and a sophisticated Lagrangian stochastic model. Both models underestimated emissions by approximately 30 %, and no statistical differences were observed between the models. Footprint models are critically important for interpreting eddy covariance measurements.
Timothy G. Pernini, T. Scott Zaccheo, Jeremy T. Dobler, and Nathan Blume
Atmos. Meas. Tech. Discuss.,
Revised manuscript accepted for AMTShort summary
We demonstrate a novel approach to estimating emissions from oil sands operations that utilizes the GreenLITE™ gas concentration measurement system and an atmospheric model. While deployed at a facility in the Athabasca region of Alberta, Canada, CH4 emissions from a tailings pond were estimated to be 7.2 t/day for Jul–Oct 2019, and 5.1 t/day for Mar–Jul 2020. CH4 emissions from an open-pit mine were estimated to be 24.6 t/day for Sep–Oct 2019.
Teles C. Furlani, Patrick R. Veres, Kathryn E. R. Dawe, J. Andrew Neuman, Steven S. Brown, Trevor C. VandenBoer, and Cora J. Young
Atmos. Meas. Tech., 14, 5859–5871,Short summary
This study characterized and validated a commercial spectroscopic instrument for the measurement of hydrogen chloride (HCl) in the atmosphere. Near the Earth’s surface, HCl acts as the dominant reservoir for other chlorine-containing reactive chemicals that play an important role in atmospheric chemistry. The properties of HCl make it challenging to measure. This instrument can overcome many of these challenges, enabling reliable HCl measurements.
Daniel R. Peters, Olalekan A. M. Popoola, Roderic L. Jones, Nicholas A. Martin, Jim Mills, Elizabeth R. Fonseca, Amy Stidworthy, Ella Forsyth, David Carruthers, Megan Dupuy-Todd, Felicia Douglas, Katie Moore, Rishabh U. Shah, Lauren E. Padilla, and Ramón A. Alvarez
Atmos. Meas. Tech. Discuss.,
Revised manuscript accepted for AMTShort summary
We present more than two years of NO2 pollution measurements from a sensor network in Greater London and compare results to an extensive network of expensive reference-grade monitors. We show the ability of our lower-cost network to generate robust insights about local air pollution. We also show how irregularities in sensor performance lead to some uncertainty in results, and demonstrate ways that future users can characterize and mitigate uncertainties to get the most value from sensor data.
Marvin Glowania, Franz Rohrer, Hans-Peter Dorn, Andreas Hofzumahaus, Frank Holland, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Meas. Tech., 14, 4239–4253,Short summary
Three instruments that use different techniques to measure gaseous formaldehyde concentrations were compared in experiments in the atmospheric simulation chamber SAPHIR at Forschungszentrum Jülich. The results demonstrated the need to correct the baseline in measurements by instruments that use the Hantzsch reaction or make use of cavity ring-down spectroscopy. After applying corrections, all three methods gave accurate and precise measurements within their specifications.
Attilio Naccarato, Antonella Tassone, Maria Martino, Sacha Moretti, Antonella Macagnano, Emiliano Zampetti, Paolo Papa, Joshua Avossa, Nicola Pirrone, Michelle Nerentorp, John Munthe, Ingvar Wängberg, Geoff W. Stupple, Carl P. J. Mitchell, Adam R. Martin, Alexandra Steffen, Diana Babi, Eric M. Prestbo, Francesca Sprovieri, and Frank Wania
Atmos. Meas. Tech., 14, 3657–3672,Short summary
Mercury monitoring in support of the Minamata Convention requires effective and reliable analytical tools. Passive sampling is a promising approach for creating a sustainable long-term network for atmospheric mercury with improved spatial resolution and global coverage. In this study the analytical performance of three passive air samplers (CNR-PAS, IVL-PAS, and MerPAS) was assessed over extended deployment periods and the accuracy of concentrations was judged by comparison with active sampling.
Mei Bai, José I. Velazco, Trevor W. Coates, Frances A. Phillips, Thomas K. Flesch, Julian Hill, David G. Mayer, Nigel W. Tomkins, Roger S. Hegarty, and Deli Chen
Atmos. Meas. Tech., 14, 3469–3479,Short summary
The development and validation of management practices to mitigate methane (CH4) emissions from livestock require accurate emission measurements. We compared the inverse dispersion modelling (IDM) and tracer-ratio techniques to measure CH4 emissions from cattle. Both measurements agreed well but were higher than IPCC estimates. We suggest that the IDM approach can provide an accurate method of estimating cattle emissions, and IPCC estimates may have larger uncertainties.
Yuan You, Ralf M. Staebler, Samar G. Moussa, James Beck, and Richard L. Mittermeier
Atmos. Meas. Tech., 14, 1879–1892,Short summary
Tailings ponds in the Alberta oil sands can be significant sources of methane, an important greenhouse gas. This paper describes a 1-month study conducted in 2017 to measure methane emissions from a pond using a variety of micrometeorological flux methods and demonstrates some advantages of these methods over flux chambers.
Christoph Häni, Marcel Bühler, Albrecht Neftel, Christof Ammann, and Thomas Kupper
Atmos. Meas. Tech., 14, 1733–1741,
Seth Kutikoff, Xiaomao Lin, Steven R. Evett, Prasanna Gowda, David Brauer, Jerry Moorhead, Gary Marek, Paul Colaizzi, Robert Aiken, Liukang Xu, and Clenton Owensby
Atmos. Meas. Tech., 14, 1253–1266,Short summary
Fast-response infrared gas sensors have been used over 3 decades for long-term monitoring of water vapor fluxes. As optically improved infrared gas sensors are newly employed, we evaluated the performance of water vapor density and water vapor flux from three generations of infrared gas sensors in Bushland, Texas, USA. From our experiments, fluxes from the old sensors were best representative of evapotranspiration based on a world-class lysimeter reference measurement.
Yuan You, Samar G. Moussa, Lucas Zhang, Long Fu, James Beck, and Ralf M. Staebler
Atmos. Meas. Tech., 14, 945–959,Short summary
Tailings ponds in the Alberta oil sands represent an insufficiently characterized source of fugitive emissions of pollutants to the atmosphere. In this study, a novel approach of using a Fourier transform infrared spectrometer along with measurements of atmospheric turbulence is shown to present a practical, non-intrusive method of quantifying emission rates for ammonia, alkanes, and methane. Results from a 1-month field study are presented and discussed.
Ravi Sahu, Ayush Nagal, Kuldeep Kumar Dixit, Harshavardhan Unnibhavi, Srikanth Mantravadi, Srijith Nair, Yogesh Simmhan, Brijesh Mishra, Rajesh Zele, Ronak Sutaria, Vidyanand Motiram Motghare, Purushottam Kar, and Sachchida Nand Tripathi
Atmos. Meas. Tech., 14, 37–52,Short summary
A unique feature of our low-cost sensor deployment is a swap-out experiment wherein four of the six sensors were relocated to different sites in the two phases. The swap-out experiment is crucial in investigating the efficacy of calibration models when applied to weather and air quality conditions vastly different from those present during calibration. We developed a novel local calibration algorithm based on metric learning that offers stable and accurate calibration performance.
Michal Vojtisek-Lom, Alessandro A. Zardini, Martin Pechout, Lubos Dittrich, Fausto Forni, François Montigny, Massimo Carriero, Barouch Giechaskiel, and Giorgio Martini
Atmos. Meas. Tech., 13, 5827–5843,Short summary
The feasibility of monitoring on-road emissions from small motorcycles with two highly compact portable emissions monitoring systems was evaluated on three motorcycles, with positive results. Mass emissions measured on the road were consistent among repeated runs, with differences between laboratory and on-road tests much larger than those between portable and laboratory systems, which were, on the average, within units of percent over standard test cycles.
Xiaoyu Sun, Minzheng Duan, Yang Gao, Rui Han, Denghui Ji, Wenxing Zhang, Nong Chen, Xiangao Xia, Hailei Liu, and Yanfeng Huo
Atmos. Meas. Tech., 13, 3595–3607,Short summary
The accurate measurement of greenhouse gases and their vertical distribution in the atmosphere is significant to the study of climate change and satellite remote sensing. Carbon dioxide and methane between 0.6 and 7 km were measured by the aircraft King Air 350ER in Jiansanjiang, northeast China, on 7–11 August 2018. The profiles show strong variation with the altitude and time, so the vertical structure of gases should be taken into account in the current satellite retrieval algorithm.
Paul A. Solomon, Dena Vallano, Melissa Lunden, Brian LaFranchi, Charles L. Blanchard, and Stephanie L. Shaw
Atmos. Meas. Tech., 13, 3277–3301,Short summary
Analyzing street-level air pollutants (2016–2017), this assessment indicates that mobile measurement is precise and accurate (5 % to 25 % bias) relative to regulatory sites, with higher spatial resolution. Collocated sensor measurements in California showed differences less than 20 %, suggesting that greater differences represent spatial variability. Mobile data confirm regulatory-site spatial representation and that pollutant levels can also be 6 to 8 times higher just blocks apart.
Christian Juncher Jørgensen, Jacob Mønster, Karsten Fuglsang, and Jesper Riis Christiansen
Atmos. Meas. Tech., 13, 3319–3328,Short summary
Recent discoveries have shown large emissions of methane (CH4) to the atmosphere from meltwater at the Greenland ice sheet (GrIS). Low-cost and low-power gas sensor technology offers great potential to supplement CH4 measurements using very expensive reference analyzers under harsh and remote conditions. In this paper we evaluate the in situ performance at the GrIS of a low-cost CH4 sensor to a state-of-the-art analyzer and find very excellent agreement between the two methods.
Lilian Joly, Olivier Coopmann, Vincent Guidard, Thomas Decarpenterie, Nicolas Dumelié, Julien Cousin, Jérémie Burgalat, Nicolas Chauvin, Grégory Albora, Rabih Maamary, Zineb Miftah El Khair, Diane Tzanos, Joël Barrié, Éric Moulin, Patrick Aressy, and Anne Belleudy
Atmos. Meas. Tech., 13, 3099–3118,Short summary
This article presents an instrument weighing less than 3 kg for accurate and rapid measurement of greenhouse gases between 0 and 30 km altitude using a meteorological balloon. This article shows the interest of these measurements for the validation of simulations of infrared satellite observations.
Jonathan Elsey, Marc D. Coleman, Tom D. Gardiner, Kaah P. Menang, and Keith P. Shine
Atmos. Meas. Tech., 13, 2335–2361,Short summary
Water vapour is an important component in trying to understand the flows of energy between the Sun and Earth, since it is opaque to radiation emitted by both the surface and the Sun. In this paper, we study how it absorbs sunlight by way of its
continuum, a property which is poorly understood and with few measurements. Our results indicate that this continuum absorption may be more significant than previously thought, potentially impacting satellite observations and climate studies.
Claudia Grossi, Scott D. Chambers, Olivier Llido, Felix R. Vogel, Victor Kazan, Alessandro Capuana, Sylvester Werczynski, Roger Curcoll, Marc Delmotte, Arturo Vargas, Josep-Anton Morguí, Ingeborg Levin, and Michel Ramonet
Atmos. Meas. Tech., 13, 2241–2255,Short summary
The sustainable support of radon metrology at the environmental level offers new scientific possibilities for the quantification of greenhouse gas (GHG) emissions and the determination of their source terms as well as for the identification of radioactive sources for the assessment of radiation exposure. This study helps to harmonize the techniques commonly used for atmospheric radon and radon progeny activity concentration measurements.
Cheng-Hsien Lin, Richard H. Grant, Albert J. Heber, and Cliff T. Johnston
Atmos. Meas. Tech., 13, 2001–2013,Short summary
Gas quantification using the open-path Fourier transform infrared spectrometer (OP-FTIR) is subject to interferences of environmental variables, leading to errors in gas concentration calculations. This study investigated the effects of ambient water vapour content, temperature, path lengths, and wind speed on the quantification of N2O and CO2 concentrations, which can help the OP-FTIR users to avoid these errors and improve the precision and accuracy of the atmospheric gas quantification.
Rachel Edie, Anna M. Robertson, Robert A. Field, Jeffrey Soltis, Dustin A. Snare, Daniel Zimmerle, Clay S. Bell, Timothy L. Vaughn, and Shane M. Murphy
Atmos. Meas. Tech., 13, 341–353,Short summary
Ground-based measurements of emissions from oil and natural gas production are important for understanding emission distributions and improving emission inventories. Here, measurement technique Other Test Method 33A (OTM 33A) is validated through several test releases staged at the Methane Emissions Technology Evaluation Center. These tests suggest OTM 33A has no inherent bias and that a group of OTM measurements is within 5 % of the known mean emission rate.
Zheng Xu, Yuliang Liu, Wei Nie, Peng Sun, Xuguang Chi, and Aijun Ding
Atmos. Meas. Tech., 12, 6737–6748,Short summary
We evaluated the performance of HONO measurement by a wet-denuder--ion0chromatography system (WD/IC, MARGA). We found significant artificial HONO formed from the reaction of NO2 oxidizing SO2 in the denuder solution. High ambient NH3 would elevate the pH of the denuder solution and promote the overestimation of HONO. A method was established to correct the HONO measurement by WD/IC instruments.
Leigh R. Crilley, Louisa J. Kramer, Bin Ouyang, Jun Duan, Wenqian Zhang, Shengrui Tong, Maofa Ge, Ke Tang, Min Qin, Pinhua Xie, Marvin D. Shaw, Alastair C. Lewis, Archit Mehra, Thomas J. Bannan, Stephen D. Worrall, Michael Priestley, Asan Bacak, Hugh Coe, James Allan, Carl J. Percival, Olalekan A. M. Popoola, Roderic L. Jones, and William J. Bloss
Atmos. Meas. Tech., 12, 6449–6463,Short summary
Nitrous acid (HONO) is key species for understanding tropospheric chemistry, yet accurate and precise measurements are challenging. Here we report an inter–comparison exercise of a number of instruments that measured HONO in a highly polluted location (Beijing). All instruments agreed on the temporal trends yet displayed divergence in absolute concentrations. The cause of this divergence was unclear, but it may in part be due to spatial variability in instrument location.
Rupert Holzinger, W. Joe F. Acton, William J. Bloss, Martin Breitenlechner, Leigh R. Crilley, Sébastien Dusanter, Marc Gonin, Valerie Gros, Frank N. Keutsch, Astrid Kiendler-Scharr, Louisa J. Kramer, Jordan E. Krechmer, Baptiste Languille, Nadine Locoge, Felipe Lopez-Hilfiker, Dušan Materić, Sergi Moreno, Eiko Nemitz, Lauriane L. J. Quéléver, Roland Sarda Esteve, Stéphane Sauvage, Simon Schallhart, Roberto Sommariva, Ralf Tillmann, Sergej Wedel, David R. Worton, Kangming Xu, and Alexander Zaytsev
Atmos. Meas. Tech., 12, 6193–6208,
Christoph Zellweger, Rainer Steinbrecher, Olivier Laurent, Haeyoung Lee, Sumin Kim, Lukas Emmenegger, Martin Steinbacher, and Brigitte Buchmann
Atmos. Meas. Tech., 12, 5863–5878,Short summary
We analysed results obtained through CO and N2O performance audits conducted within the framework of the Global Atmosphere Watch (GAW) quality management system of the World Meteorology Organization (WMO). The results reveal that current spectroscopic measurement techniques have clear advantages with respect to data quality objectives compared to more traditional methods. Further, they allow for a smooth continuation of historic CO and N2O time series.
Lukas Siebicke and Anas Emad
Atmos. Meas. Tech., 12, 4393–4420,Short summary
We present the emerging flux measurement method
true eddy accumulation(TEA), able to quantify the land–atmosphere exchange of a large number of trace gases which are important for air quality and atmospheric composition. Our innovative implementation provides proof of concept of TEA and compared well to the established reference, outperforming previous works on TEA. Key to the success was the innovative high-speed air sampling and fully digital real-time data processing system.
Loic Lechevallier, Roberto Grilli, Erik Kerstel, Daniele Romanini, and Jérôme Chappellaz
Atmos. Meas. Tech., 12, 3101–3109,Short summary
In this work we describe a highly sensitive optical spectrometer for simultaneous measurement of methane, ethane, and the isotopic composition of methane. The coupling of the spectrometer with a dissolved gas extraction system will provide a suitable tool for understanding the origins of the dissolved hydrocarbons and discriminate between the different sources (e.g., biogenic vs. thermogenic).
Kate R. Smith, Peter M. Edwards, Peter D. Ivatt, James D. Lee, Freya Squires, Chengliang Dai, Richard E. Peltier, Mat J. Evans, Yele Sun, and Alastair C. Lewis
Atmos. Meas. Tech., 12, 1325–1336,Short summary
Clusters of low-cost, low-power atmospheric gas sensors were built into a sensor instrument to monitor NO2 and O3 in Beijing, alongside reference instruments, aiming to improve the reliability of sensor measurements. Clustering identical sensors and using the median sensor signal was used to minimize drift over short and medium timescales. Three different machine learning techniques were used for all the sensor data in an attempt to correct for cross-interferences, which worked to some degree.
Mei Bai, Helen Suter, Shu Kee Lam, Thomas K. Flesch, and Deli Chen
Atmos. Meas. Tech., 12, 1095–1102,Short summary
Improving direct field measurement techniques to quantify gas emissions from large agriculture farm is challenging. We measured nitrous oxide (N2O) emissions with static closed chambers and slant open-path flux gradient (FG) approaches following chicken manure application. The concurrent emission ratios (FG / chamber) showed N2O fluxes measured by FG were 1.22-1.40 times higher than those from the chambers. This study provides important information for the agriculture gas measurement community.
Vincent Michoud, Stéphane Sauvage, Thierry Léonardis, Isabelle Fronval, Alexandre Kukui, Nadine Locoge, and Sébastien Dusanter
Atmos. Meas. Tech., 11, 5729–5740,Short summary
This study presents the first measurements of ambient methylglyoxal, an important atmospheric α-dicarbonyl, using proton transfer reaction time-of-flight mass spectrometry. These measurements mostly agree with concomitant measurements from a reference technique: the DNPH derivatization technique and high-performance liquid chromatography with UV detection. In addition, a careful investigation of the differences between the two techniques is carried out to explain the disagreements observed.
Michael J. Prather, Clare M. Flynn, Xin Zhu, Stephen D. Steenrod, Sarah A. Strode, Arlene M. Fiore, Gustavo Correa, Lee T. Murray, and Jean-Francois Lamarque
Atmos. Meas. Tech., 11, 2653–2668,Short summary
A new protocol for merging in situ atmospheric chemistry measurements with 3-D models is developed. This technique can identify the most reactive air parcels in terms of tropospheric production/loss of O3 & CH4. This approach highlights differences in 6 global chemistry models even with composition specified. Thus in situ measurements from, e.g., NASA's ATom mission can be used to develop a chemical climatology of, not only the key species, but also the rates of key reactions in each air parcel.
Richard H. Grant and Rex A. Omonode
Atmos. Meas. Tech., 11, 2119–2133,Short summary
Annual emissions of trace gases requires knowledge of the emissions throughout the day and year. Unfortunately emissions into the surface boundary layer during calm nights are rarely measured. During such conditions surface layer concentrations of carbon dioxide (CO2) and nitrous oxide (N2O) often accumulate in the surface boundary layer and the time rate of change of this accumulation was used to estimate emissions. Results showed this approach to be reasonable.
Kira Sadighi, Evan Coffey, Andrea Polidori, Brandon Feenstra, Qin Lv, Daven K. Henze, and Michael Hannigan
Atmos. Meas. Tech., 11, 1777–1792,Short summary
Ground-level ozone has negative human health impacts. In the summer of 2015, 13 low-cost sensor monitors were deployed to several neighborhoods around Riverside, California. There were significant spatial differences between monitors. This is important because it means that ozone in certain places may be higher than what EPA monitors report for an area, which is pertinent for residents of those communities. This research helps inform the limitations and advantages of low-cost sensor networks.
Bas Mijling, Qijun Jiang, Dave de Jonge, and Stefano Bocconi
Atmos. Meas. Tech., 11, 1297–1312,Short summary
Although in many cities the population is exposed to air pollution, real-time air quality is usually only measured at a few locations. New low-cost sensor technology has the potential to extend the monitoring network significantly. We show that citizen science campaigns using the current generations of electrochemical NO2 sensors may provide useful complementary data on local air quality in an urban setting, provided that experiments are properly set up and the data are carefully analysed.
Natasha L. Miles, Douglas K. Martins, Scott J. Richardson, Christopher W. Rella, Caleb Arata, Thomas Lauvaux, Kenneth J. Davis, Zachary R. Barkley, Kathryn McKain, and Colm Sweeney
Atmos. Meas. Tech., 11, 1273–1295,Short summary
Analyzers measuring methane and methane isotopic ratio were deployed at four towers in the Marcellus Shale natural gas extraction region of Pennsylvania. The methane isotopic ratio is helpful for differentiating emissions from natural gas activities from other sources (e.g., landfills). We describe the analyzer calibration. The signals observed in the study region were generally small, but the instrumental performance demonstrated here could be used in regions with stronger enhancements.
David H. Hagan, Gabriel Isaacman-VanWertz, Jonathan P. Franklin, Lisa M. M. Wallace, Benjamin D. Kocar, Colette L. Heald, and Jesse H. Kroll
Atmos. Meas. Tech., 11, 315–328,Short summary
The use of low-cost sensors for air pollution research has outpaced our understanding of their capabilities and limitations under real-world conditions. Here we describe the deployment, calibration and evaluation of electrochemical sensors on the Island of Hawai‘i. We obtain excellent performance (RMSE < 7 ppb, r2 = 0.997) across a wide dynamic range (1 ppb–2 ppm). We introduce a hybrid regression algorithm which works across a large dynamic range and shows little decay in sensitivity over time.
Erin Dunne, Ian E. Galbally, Min Cheng, Paul Selleck, Suzie B. Molloy, and Sarah J. Lawson
Atmos. Meas. Tech., 11, 141–159,Short summary
A comparison of measurements of 7 volatile organic compounds (VOCs) in urban air by 3 different methods is presented. An uncertainty was calculated for each method and VOCs measured to provide some idea of the reliability of the data. Even when this uncertainty was accounted for, the measurements from the different methods did not agree for 4 of the 7 VOCs. Thus, there is unaccounted uncertainty in VOC measurements which must be considered when utilizing the data and assessing their reliability.
Michelle M. Lew, Sebastien Dusanter, and Philip S. Stevens
Atmos. Meas. Tech., 11, 95–109,Short summary
This paper describes measurements of the conversion efficiency of several organic peroxy radicals upon reaction with nitric oxide to the hydroperoxy radical, which can interfere with measurements of the latter. This interference could explain some of the discrepancies between measurements and model predictions of the hydroperoxy radical. Previous measurements of the hydroperoxy radical during the Mexico City Metropolitan Area campaign in 2006 are reanalyzed to account for the interference.
Pamela Rickly and Philip S. Stevens
Atmos. Meas. Tech., 11, 1–16,Short summary
The hydroxyl radical is the primary atmospheric oxidant in the atmosphere, and measurements of its concentration provide a rigorous test of our understanding of atmospheric chemistry. This paper presents measurements of a potential interference with measurements of OH using laser-induced fluorescence techniques, which may contribute to measurements of OH in forested environments. The results may help to explain discrepancies between measurements and model predictions in these environments.
Sébastien Ars, Grégoire Broquet, Camille Yver Kwok, Yelva Roustan, Lin Wu, Emmanuel Arzoumanian, and Philippe Bousquet
Atmos. Meas. Tech., 10, 5017–5037,Short summary
This study presents a new concept for estimating the pollutant emission rates of a site combining the tracer release method, local-scale atmospheric transport modelling and a statistical atmospheric inversion approach. The potential of this new concept is evaluated with a practical implementation based on a series of inversions of controlled methane and tracer point sources in different spatial configurations to assess the efficiency of the method in comparison with the classic tracer method.
Hendrik Fuchs, Anna Novelli, Michael Rolletter, Andreas Hofzumahaus, Eva Y. Pfannerstill, Stephan Kessel, Achim Edtbauer, Jonathan Williams, Vincent Michoud, Sebastien Dusanter, Nadine Locoge, Nora Zannoni, Valerie Gros, Francois Truong, Roland Sarda-Esteve, Danny R. Cryer, Charlotte A. Brumby, Lisa K. Whalley, Daniel Stone, Paul W. Seakins, Dwayne E. Heard, Coralie Schoemaecker, Marion Blocquet, Sebastien Coudert, Sebastien Batut, Christa Fittschen, Alexander B. Thames, William H. Brune, Cheryl Ernest, Hartwig Harder, Jennifer B. A. Muller, Thomas Elste, Dagmar Kubistin, Stefanie Andres, Birger Bohn, Thorsten Hohaus, Frank Holland, Xin Li, Franz Rohrer, Astrid Kiendler-Scharr, Ralf Tillmann, Robert Wegener, Zhujun Yu, Qi Zou, and Andreas Wahner
Atmos. Meas. Tech., 10, 4023–4053,Short summary
Hydroxyl radical reactivity (k(OH)) is closely related to processes that lead to the formation of oxidised, secondary pollutants such as ozone and aerosol. In order to compare the performances of instruments measuring k(OH), experiments were conducted in the simulation chamber SAPHIR. Chemical conditions were chosen either to be representative of the atmosphere or to test potential limitations of instruments. Overall, the results show that instruments are capable of measuring k(OH).
Eben S. Cross, Leah R. Williams, David K. Lewis, Gregory R. Magoon, Timothy B. Onasch, Michael L. Kaminsky, Douglas R. Worsnop, and John T. Jayne
Atmos. Meas. Tech., 10, 3575–3588,Short summary
Low-cost air quality sensor technologies offer new opportunities for fast and distributed measurements of air pollution, but a persistent characterization gap remains when it comes to evaluating sensor performance under realistic environmental sampling conditions. We present results from a newly developed integrated AQ-sensor system (ARISense) and demonstrate the utility of using high-dimensional model representation to improve the conversion of raw sensor signal to ambient concentration.
Abigail Koss, Bin Yuan, Carsten Warneke, Jessica B. Gilman, Brian M. Lerner, Patrick R. Veres, Jeff Peischl, Scott Eilerman, Rob Wild, Steven S. Brown, Chelsea R. Thompson, Thomas Ryerson, Thomas Hanisco, Glenn M. Wolfe, Jason M. St. Clair, Mitchell Thayer, Frank N. Keutsch, Shane Murphy, and Joost de Gouw
Atmos. Meas. Tech., 10, 2941–2968,Short summary
Oil and gas extraction activity can cause air quality issues through emission of reactive chemicals. VOCs related to extraction operations in the United States were measured by PTR-ToF-MS from aircraft during the SONGNEX campaign in March–April 2015. The detailed analysis in this work provides a guide to interpreting PTR-ToF measurements in oil- and gas-producing regions, and it includes fundamental observations of VOC speciation and mixing ratios.
Caroline Brosy, Karina Krampf, Matthias Zeeman, Benjamin Wolf, Wolfgang Junkermann, Klaus Schäfer, Stefan Emeis, and Harald Kunstmann
Atmos. Meas. Tech., 10, 2773–2784,Short summary
Vertical and horizontal sounding of the planetary boundary layer can be complemented by unmanned aerial vehicles (UAV). Utilizing a multicopter-type UAV spatial sampling of air and simultaneously sensing of meteorological variables is possible for the study of surface exchange processes. During stable atmospheric conditions, vertical methane gradients of about 300 ppb were found. This approach extended the vertical profile height of existing tower-based infrastructure by a factor of five.
Cory R. Martin, Ning Zeng, Anna Karion, Russell R. Dickerson, Xinrong Ren, Bari N. Turpie, and Kristy J. Weber
Atmos. Meas. Tech., 10, 2383–2395,Short summary
A low-cost sensor for measuring carbon dioxide is evaluated for its performance in detecting concentrations in Earth's atmosphere. After a multivariate regression correcting for environmental variables, the root mean square error between it and a research-grade gas analyzer is less than 0.5 % of the observed average value. This demonstrates the viability for using these sensors in certain real-world atmospheric observing applications.
Lukas Lesmeister and Matthias Koschorreck
Atmos. Meas. Tech., 10, 2377–2382,Short summary
Greenhouse gas emissions from dry aquatic sediments are probably globally relevant. However, they are difficult to measure because of the often rocky substrate. We tested the performance of different materials to seal a closed chamber to stony ground both in laboratory and field experiments. Pottery clay was a convenient sealing material, while the use of on-site material produced artefacts. We confirmed that CO2 fluxes from dry aquatic sediments were similar to fluxes from
Terry Deshler, Rene Stübi, Francis J. Schmidlin, Jennifer L. Mercer, Herman G. J. Smit, Bryan J. Johnson, Rigel Kivi, and Bruno Nardi
Atmos. Meas. Tech., 10, 2021–2043,Short summary
Ozonesondes, small balloon-borne instruments to measure ozone profiles, are used once and lost. Quality control is thus essential. From the mid-1990s to late 2000s differences in manufacturers' (Science Pump and ENSCI) recommended sensor solution concentrations, 1.0 % and 0.5 % potassium iodide, led to some confusion. This paper uses comparison measurements to derive transfer functions to homogenize the measurements made with non-standard combinations of instrument and sensor solution.
Irène Ventrillard, Irène Xueref-Remy, Martina Schmidt, Camille Yver Kwok, Xavier Faïn, and Daniele Romanini
Atmos. Meas. Tech., 10, 1803–1812,Short summary
We present a comparison of CO measurements performed with a portable OF-CEAS laser spectrometer against a high-performance gas chromatograph. For both surface and airborne measurements, the instruments show an excellent agreement very close to the 2 ppb World Meteorological Organization recommendation for CO inter-laboratory comparison. This work establishes that this laser technique allows for the development of sensitive, compact, robust and reliable instruments for in situ trace-gas analysis.
Dominik Schmithüsen, Scott Chambers, Bernd Fischer, Stefan Gilge, Juha Hatakka, Victor Kazan, Rolf Neubert, Jussi Paatero, Michel Ramonet, Clemens Schlosser, Sabine Schmid, Alex Vermeulen, and Ingeborg Levin
Atmos. Meas. Tech., 10, 1299–1312,Short summary
A European-wide 222radon/222radon progeny comparison study has been conducted at nine measurement stations in order to determine differences between existing 222radon instrumentation and atmospheric data sets, respectively. Mean differences up to 45 % were found between monitors. These differences need to be taken into account if the data shall serve for quantitative regional atmospheric transport model validation.
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Fischer, E. V., Jaffe, D. A., Reidmiller, D. R., and Jaegle, L.: Meteorological controls on observed peroxyacetyl nitrate at Mount Bachelor during the spring of 2008, J. Geophys. Res., 115, D03302, https://doi.org/10.1029/2009JD012776, 2010.
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A photochemical source of peroxycarboxylic nitric anhydrides (PANs) in which a dialkyl ketone (acetone, diethyl-, di-isopropyl, or di-n-propyl ketone) in the presence of oxygen and nitric oxide is photodissociated by arrays of ultraviolet light-emitting diodes (UV-LEDs) is described. The source output was analyzed by gas chromatography and thermal dissociation cavity ring-down spectroscopy and modeled using the Master Chemical Mechanism.
A photochemical source of peroxycarboxylic nitric anhydrides (PANs) in which a dialkyl ketone...