Articles | Volume 3, issue 3
https://doi.org/10.5194/amt-3-683-2010
© Author(s) 2010. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/amt-3-683-2010
© Author(s) 2010. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
16 Jun 2010
Development and validation of a portable gas phase standard generation and calibration system for volatile organic compounds
P. Veres
Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309, USA
Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305, USA
J. B. Gilman
Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305, USA
Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309, USA
J. M. Roberts
Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305, USA
W. C. Kuster
Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305, USA
C. Warneke
Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305, USA
Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309, USA
I. R. Burling
University of Montana, Department of Chemistry, Missoula, USA
J. de Gouw
Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305, USA
Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309, USA
Related subject area
Subject: Gases | Technique: In Situ Measurement | Topic: Validation and Intercomparisons
Intercomparison of commercial analyzers for atmospheric ethane and methane observations
Real-time measurement of phase partitioning of organic compounds using a proton-transfer-reaction time-of-flight mass spectrometer coupled to a CHARON inlet
Comparison of atmospheric CO, CO2 and CH4 measurements at Schneefernerhaus and the mountain ridge at Zugspitze
A quantitative comparison of methods used to measure smaller methane emissions typically observed from superannuated oil and gas infrastructure
Comparing airborne algorithms for greenhouse gas flux measurements over the Alberta oil sands
Characterization of inexpensive metal oxide sensor performance for trace methane detection
Intercomparison of upper tropospheric and lower stratospheric water vapor measurements over the Asian Summer Monsoon during the StratoClim campaign
Air pollution measurement errors: is your data fit for purpose?
Performance characterization of low-cost air quality sensors for off-grid deployment in rural Malawi
Comment on “Comparison of ozone measurement methods in biomass burning smoke: an evaluation under field and laboratory conditions” by Long et al. (2021)
Homogenization of the Observatoire de Haute Provence electrochemical concentration cell (ECC) ozonesonde data record: comparison with lidar and satellite observations
Long-term behavior and stability of calibration models for NO and NO2 low-cost sensors
Controlled-release experiment to investigate uncertainties in UAV-based emission quantification for methane point sources
Ozone formation sensitivity study using machine learning coupled with the reactivity of volatile organic compound species
Evaluating uncertainty in sensor networks for urban air pollution insights
Estimating oil sands emissions using horizontal path-integrated column measurements
Global evaluation of the precipitable-water-vapor product from MERSI-II (Medium Resolution Spectral Imager) on board the Fengyun-3D satellite
Field testing two flux footprint models
Validation of a new cavity ring-down spectrometer for measuring tropospheric gaseous hydrogen chloride
Comparison of formaldehyde measurements by Hantzsch, CRDS and DOAS in the SAPHIR chamber
A field intercomparison of three passive air samplers for gaseous mercury in ambient air
Beef cattle methane emissions measured with tracer-ratio and inverse dispersion modelling techniques
Methane emissions from an oil sands tailings pond: a quantitative comparison of fluxes derived by different methods
Performance of open-path GasFinder3 devices for CH4 concentration measurements close to ambient levels
Water vapor density and turbulent fluxes from three generations of infrared gas analyzers
Quantifying fugitive gas emissions from an oil sands tailings pond with open-path Fourier transform infrared measurements
Robust statistical calibration and characterization of portable low-cost air quality monitoring sensors to quantify real-time O3 and NO2 concentrations in diverse environments
A miniature Portable Emissions Measurement System (PEMS) for real-driving monitoring of motorcycles
In situ measurement of CO2 and CH4 from aircraft over northeast China and comparison with OCO-2 data
Mobile-platform measurement of air pollutant concentrations in California: performance assessment, statistical methods for evaluating spatial variations, and spatial representativeness
Continuous methane concentration measurements at the Greenland ice sheet–atmosphere interface using a low-cost, low-power metal oxide sensor system
The development of the Atmospheric Measurements by Ultra-Light Spectrometer (AMULSE) greenhouse gas profiling system and application for satellite retrieval validation
Atmospheric observations of the water vapour continuum in the near-infrared windows between 2500 and 6600 cm−1
Intercomparison study of atmospheric 222Rn and 222Rn progeny monitors
Sources of error in open-path FTIR measurements of N2O and CO2 emitted from agricultural fields
Constraining the accuracy of flux estimates using OTM 33A
Evaluating the measurement interference of wet rotating-denuder–ion chromatography in measuring atmospheric HONO in a highly polluted area
Intercomparison of nitrous acid (HONO) measurement techniques in a megacity (Beijing)
Validity and limitations of simple reaction kinetics to calculate concentrations of organic compounds from ion counts in PTR-MS
Recent advances in measurement techniques for atmospheric carbon monoxide and nitrous oxide observations
True eddy accumulation trace gas flux measurements: proof of concept
Simultaneous detection of C2H6, CH4, and δ13C-CH4 using optical feedback cavity-enhanced absorption spectroscopy in the mid-infrared region: towards application for dissolved gas measurements
An improved low-power measurement of ambient NO2 and O3 combining electrochemical sensor clusters and machine learning
Comparison of slant open-path flux gradient and static closed chamber techniques to measure soil N2O emissions
Field measurements of methylglyoxal using proton transfer reaction time-of-flight mass spectrometry and comparison to the DNPH–HPLC–UV method
How well can global chemistry models calculate the reactivity of short-lived greenhouse gases in the remote troposphere, knowing the chemical composition
Estimation of nocturnal CO2 and N2O soil emissions from changes in surface boundary layer mass storage
Intra-urban spatial variability of surface ozone in Riverside, CA: viability and validation of low-cost sensors
Field calibration of electrochemical NO2 sensors in a citizen science context
Calibration and field testing of cavity ring-down laser spectrometers measuring CH4, CO2, and δ13CH4 deployed on towers in the Marcellus Shale region
Róisín Commane, Andrew Hallward-Driemeier, and Lee T. Murray
Atmos. Meas. Tech., 16, 1431–1441, https://doi.org/10.5194/amt-16-1431-2023, https://doi.org/10.5194/amt-16-1431-2023, 2023
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Methane / ethane ratios can be used to identify and partition the different sources of methane, especially in areas with natural gas mixed with biogenic methane emissions, such as cities. We tested three commercially available laser-based analyzers for sensitivity, precision, size, power requirement, ease of use on mobile platforms, and expertise needed to operate the instrument, and we make recommendations for use in various situations.
Yarong Peng, Hongli Wang, Yaqin Gao, Shengao Jing, Shuhui Zhu, Dandan Huang, Peizhi Hao, Shengrong Lou, Tiantao Cheng, Cheng Huang, and Xuan Zhang
Atmos. Meas. Tech., 16, 15–28, https://doi.org/10.5194/amt-16-15-2023, https://doi.org/10.5194/amt-16-15-2023, 2023
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This work examined the phase partitioning behaviors of organic compounds at hourly resolution in ambient conditions with the use of the CHemical Analysis of aeRosols ONline (CHARON) inlet coupled to a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS). Properly accounting for the neutral losses of small moieties during the molecular feature extraction from PTR mass spectra could significantly reduce uncertainties associated with the gas–particle partitioning measurements.
Antje Hoheisel, Cedric Couret, Bryan Hellack, and Martina Schmidt
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2022-298, https://doi.org/10.5194/amt-2022-298, 2022
Revised manuscript accepted for AMT
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High-precision CO2, CH4 and CO measurements have been carried out at Zugspitze for decades. New technologies now make it possible to analyse these gases with high temporal resolution. This allows for detection of local pollution. For this purpose, measurements have been performed on the mountain ridge (ZGR) and are compared to routine measurements at Schneefernerhaus (ZSF). Careful manual flagging of pollution events in the ZSF data lead to consistency with the hardly influenced ZGR time series.
Stuart N. Riddick, Riley Ancona, Mercy Mbua, Clay S. Bell, Aidan Duggan, Timothy L. Vaughn, Kristine Bennett, and Daniel J. Zimmerle
Atmos. Meas. Tech., 15, 6285–6296, https://doi.org/10.5194/amt-15-6285-2022, https://doi.org/10.5194/amt-15-6285-2022, 2022
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This describes controlled release experiments at the METEC facility in Fort Collins, USA, that investigates the accuracy and precision of five methods commonly used to measure methane emissions. Methods include static/dynamic chambers, hi flow sampling, a backward Lagrangian stochastic method, and a Gaussian plume method. This is the first time that methods for measuring CH4 emissions from point sources less than 200 g CH4 h−1 have been quantitively assessed against references and each other.
Broghan M. Erland, Cristen Adams, Andrea Darlington, Mackenzie L. Smith, Andrew K. Thorpe, Gregory R. Wentworth, Steve Conley, John Liggio, Shao-Meng Li, Charles E. Miller, and John A. Gamon
Atmos. Meas. Tech., 15, 5841–5859, https://doi.org/10.5194/amt-15-5841-2022, https://doi.org/10.5194/amt-15-5841-2022, 2022
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Accurately estimating greenhouse gas (GHG) emissions is essential to reaching net-zero goals to combat the climate crisis. Airborne box-flights are ideal for assessing regional GHG emissions, as they can attain small error. We compare two box-flight algorithms and found they produce similar results, but daily variability must be considered when deriving emissions inventories. Increasing the consistency and agreement between airborne methods moves us closer to achieving more accurate estimates.
Daniel Furuta, Tofigh Sayahi, Jinsheng Li, Bruce Wilson, Albert A. Presto, and Jiayu Li
Atmos. Meas. Tech., 15, 5117–5128, https://doi.org/10.5194/amt-15-5117-2022, https://doi.org/10.5194/amt-15-5117-2022, 2022
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Methane is a major greenhouse gas and contributor to climate change with various human-caused and natural sources. Currently, atmospheric methane is expensive to sense. We investigate repurposing cheap methane safety sensors for atmospheric sensing, finding several promising sensors and identifying some of the challenges in this approach. This work will help in developing inexpensive sensor networks for methane monitoring, which will aid in reducing methane leaks and emissions.
Clare E. Singer, Benjamin W. Clouser, Sergey M. Khaykin, Martina Krämer, Francesco Cairo, Thomas Peter, Alexey Lykov, Christian Rolf, Nicole Spelten, Armin Afchine, Simone Brunamonti, and Elisabeth J. Moyer
Atmos. Meas. Tech., 15, 4767–4783, https://doi.org/10.5194/amt-15-4767-2022, https://doi.org/10.5194/amt-15-4767-2022, 2022
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In situ measurements of water vapor in the upper troposphere are necessary to study cloud formation and hydration of the stratosphere but challenging due to cold–dry conditions. We compare measurements from three water vapor instruments from the StratoClim campaign in 2017. In clear sky (clouds), point-by-point differences were <1.5±8 % (<1±8 %). This excellent agreement allows detection of fine-scale structures required to understand the impact of convection on stratospheric water vapor.
Sebastian Diez, Stuart E. Lacy, Thomas J. Bannan, Michael Flynn, Tom Gardiner, David Harrison, Nicholas Marsden, Nicholas A. Martin, Katie Read, and Pete M. Edwards
Atmos. Meas. Tech., 15, 4091–4105, https://doi.org/10.5194/amt-15-4091-2022, https://doi.org/10.5194/amt-15-4091-2022, 2022
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Regardless of the cost of the measuring instrument, there are no perfect measurements. For this reason, we compare the quality of the information provided by cheap devices when they are used to measure air pollutants and we try to emphasise that before judging the potential usefulness of the devices, the user must specify his own needs. Since commonly used performance indices/metrics can be misleading in qualifying this, we propose complementary visual analysis to the more commonly used metrics.
Ashley S. Bittner, Eben S. Cross, David H. Hagan, Carl Malings, Eric Lipsky, and Andrew P. Grieshop
Atmos. Meas. Tech., 15, 3353–3376, https://doi.org/10.5194/amt-15-3353-2022, https://doi.org/10.5194/amt-15-3353-2022, 2022
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We present findings from a 1-year pilot deployment of low-cost integrated air quality sensor packages in rural Malawi using calibration models developed during collocation with US regulatory monitors. We compare the results with data from remote sensing products and previous field studies. We conclude that while the remote calibration approach can help extract useful data, great care is needed when assessing low-cost sensor data collected in regions without reference instrumentation.
Noah Bernays, Daniel A. Jaffe, Irina Petropavlovskikh, and Peter Effertz
Atmos. Meas. Tech., 15, 3189–3192, https://doi.org/10.5194/amt-15-3189-2022, https://doi.org/10.5194/amt-15-3189-2022, 2022
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Ozone is an important pollutant that impacts millions of people worldwide. It is therefore important to ensure accurate measurements. A recent surge in wildfire activity in the USA has resulted in significant enhancements in ozone concentration. However given the nature of wildfire smoke, there are questions about our ability to accurately measure ozone. In this comment, we discuss possible biases in the UV measurements of ozone in the presence of smoke.
Gérard Ancellet, Sophie Godin-Beekmann, Herman G. J. Smit, Ryan M. Stauffer, Roeland Van Malderen, Renaud Bodichon, and Andrea Pazmiño
Atmos. Meas. Tech., 15, 3105–3120, https://doi.org/10.5194/amt-15-3105-2022, https://doi.org/10.5194/amt-15-3105-2022, 2022
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The 1991–2021 Observatoire de Haute Provence electrochemical concentration cell (ECC) ozonesonde data have been homogenized according to the recommendations of the Ozonesonde Data Quality Assessment panel. Comparisons with ground-based instruments also measuring ozone at the same station (lidar, surface measurements) and with colocated satellite observations show the benefits of this homogenization. Remaining differences between ECC and other observations in the stratosphere are also discussed.
Horim Kim, Michael Müller, Stephan Henne, and Christoph Hüglin
Atmos. Meas. Tech., 15, 2979–2992, https://doi.org/10.5194/amt-15-2979-2022, https://doi.org/10.5194/amt-15-2979-2022, 2022
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In this study, the performance of electrochemical sensors for NO and NO2 for measuring air quality was determined over a longer operating period. The performance of NO sensors remained reliable for more than 18 months. However, the NO2 sensors showed decreasing performance over time. During deployment, we found that the NO2 sensors can distinguish general pollution levels, but they proved unsuitable for accurate measurements due to significant biases.
Randulph Morales, Jonas Ravelid, Katarina Vinkovic, Piotr Korbeń, Béla Tuzson, Lukas Emmenegger, Huilin Chen, Martina Schmidt, Sebastian Humbel, and Dominik Brunner
Atmos. Meas. Tech., 15, 2177–2198, https://doi.org/10.5194/amt-15-2177-2022, https://doi.org/10.5194/amt-15-2177-2022, 2022
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Mapping trace gas emission plumes using in situ measurements from unmanned aerial vehicles (UAVs) is an emerging and attractive possibility to quantify emissions from localized sources. We performed an extensive controlled-release experiment to develop an optimal quantification method and to determine the related uncertainties under various environmental and sampling conditions. Our approach was successful in quantifying local methane sources from drone-based measurements.
Junlei Zhan, Yongchun Liu, Wei Ma, Xin Zhang, Xuezhong Wang, Fang Bi, Yujie Zhang, Zhenhai Wu, and Hong Li
Atmos. Meas. Tech., 15, 1511–1520, https://doi.org/10.5194/amt-15-1511-2022, https://doi.org/10.5194/amt-15-1511-2022, 2022
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Our study investigated the O3 formation sensitivity in Beijing using a random forest model coupled with the reactivity of volatile organic
compound (VOC) species. Results found that random forest accurately predicted O3 concentration when initial VOCs were considered, and relative importance correlated well with O3 formation potential. The O3 isopleth curves calculated by the random forest model were generally comparable with those calculated by the box model.
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., 15, 321–334, https://doi.org/10.5194/amt-15-321-2022, https://doi.org/10.5194/amt-15-321-2022, 2022
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We present more than 2 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.
Timothy G. Pernini, T. Scott Zaccheo, Jeremy Dobler, and Nathan Blume
Atmos. Meas. Tech., 15, 225–240, https://doi.org/10.5194/amt-15-225-2022, https://doi.org/10.5194/amt-15-225-2022, 2022
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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/d for July–October 2019, and 5.1 t/d for March–July 2020. CH4 emissions from an open-pit mine were estimated to be 24.6 t/d for September–October 2019.
Wengang Zhang, Ling Wang, Yang Yu, Guirong Xu, Xiuqing Hu, Zhikang Fu, and Chunguang Cui
Atmos. Meas. Tech., 14, 7821–7834, https://doi.org/10.5194/amt-14-7821-2021, https://doi.org/10.5194/amt-14-7821-2021, 2021
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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, https://doi.org/10.5194/amt-14-7147-2021, https://doi.org/10.5194/amt-14-7147-2021, 2021
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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.
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, https://doi.org/10.5194/amt-14-5859-2021, https://doi.org/10.5194/amt-14-5859-2021, 2021
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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.
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, https://doi.org/10.5194/amt-14-4239-2021, https://doi.org/10.5194/amt-14-4239-2021, 2021
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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, https://doi.org/10.5194/amt-14-3657-2021, https://doi.org/10.5194/amt-14-3657-2021, 2021
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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, https://doi.org/10.5194/amt-14-3469-2021, https://doi.org/10.5194/amt-14-3469-2021, 2021
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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, https://doi.org/10.5194/amt-14-1879-2021, https://doi.org/10.5194/amt-14-1879-2021, 2021
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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, https://doi.org/10.5194/amt-14-1733-2021, https://doi.org/10.5194/amt-14-1733-2021, 2021
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, https://doi.org/10.5194/amt-14-1253-2021, https://doi.org/10.5194/amt-14-1253-2021, 2021
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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, https://doi.org/10.5194/amt-14-945-2021, https://doi.org/10.5194/amt-14-945-2021, 2021
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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, https://doi.org/10.5194/amt-14-37-2021, https://doi.org/10.5194/amt-14-37-2021, 2021
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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, https://doi.org/10.5194/amt-13-5827-2020, https://doi.org/10.5194/amt-13-5827-2020, 2020
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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, https://doi.org/10.5194/amt-13-3595-2020, https://doi.org/10.5194/amt-13-3595-2020, 2020
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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, https://doi.org/10.5194/amt-13-3277-2020, https://doi.org/10.5194/amt-13-3277-2020, 2020
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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, https://doi.org/10.5194/amt-13-3319-2020, https://doi.org/10.5194/amt-13-3319-2020, 2020
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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, https://doi.org/10.5194/amt-13-3099-2020, https://doi.org/10.5194/amt-13-3099-2020, 2020
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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, https://doi.org/10.5194/amt-13-2335-2020, https://doi.org/10.5194/amt-13-2335-2020, 2020
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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, https://doi.org/10.5194/amt-13-2241-2020, https://doi.org/10.5194/amt-13-2241-2020, 2020
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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, https://doi.org/10.5194/amt-13-2001-2020, https://doi.org/10.5194/amt-13-2001-2020, 2020
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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, https://doi.org/10.5194/amt-13-341-2020, https://doi.org/10.5194/amt-13-341-2020, 2020
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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, https://doi.org/10.5194/amt-12-6737-2019, https://doi.org/10.5194/amt-12-6737-2019, 2019
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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, https://doi.org/10.5194/amt-12-6449-2019, https://doi.org/10.5194/amt-12-6449-2019, 2019
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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, https://doi.org/10.5194/amt-12-6193-2019, https://doi.org/10.5194/amt-12-6193-2019, 2019
Christoph Zellweger, Rainer Steinbrecher, Olivier Laurent, Haeyoung Lee, Sumin Kim, Lukas Emmenegger, Martin Steinbacher, and Brigitte Buchmann
Atmos. Meas. Tech., 12, 5863–5878, https://doi.org/10.5194/amt-12-5863-2019, https://doi.org/10.5194/amt-12-5863-2019, 2019
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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, https://doi.org/10.5194/amt-12-4393-2019, https://doi.org/10.5194/amt-12-4393-2019, 2019
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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, https://doi.org/10.5194/amt-12-3101-2019, https://doi.org/10.5194/amt-12-3101-2019, 2019
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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, https://doi.org/10.5194/amt-12-1325-2019, https://doi.org/10.5194/amt-12-1325-2019, 2019
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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, https://doi.org/10.5194/amt-12-1095-2019, https://doi.org/10.5194/amt-12-1095-2019, 2019
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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, https://doi.org/10.5194/amt-11-5729-2018, https://doi.org/10.5194/amt-11-5729-2018, 2018
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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, https://doi.org/10.5194/amt-11-2653-2018, https://doi.org/10.5194/amt-11-2653-2018, 2018
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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, https://doi.org/10.5194/amt-11-2119-2018, https://doi.org/10.5194/amt-11-2119-2018, 2018
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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, https://doi.org/10.5194/amt-11-1777-2018, https://doi.org/10.5194/amt-11-1777-2018, 2018
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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, https://doi.org/10.5194/amt-11-1297-2018, https://doi.org/10.5194/amt-11-1297-2018, 2018
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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, https://doi.org/10.5194/amt-11-1273-2018, https://doi.org/10.5194/amt-11-1273-2018, 2018
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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.
Cited articles
Altshuller, A. P. and Cohen, I. R.: Application of diffusion cells to the production of known concentrations of gaseous hydrocarbons, Anal. Chem., 32, 802–810, 1960.
Apel, E. C., Calvert, J. G., and Fehsenfeld, F. C.: The nonmethane hydrocarbon intercomparison experiment (nomhice) – task 1 and task 2, J. Geophys. Res.-Atmos., 99, 16651–16664, 1994.
Apel, E. C., Calvert, J. G., Greenberg, J. P., Riemer, D., Zika, R., Kleindienst, T. E., Lonneman, W. A., Fung, K., and Fujita, E.: Generation and validation of oxygenated volatile organic carbon standards for the 1995 southern oxidants study nashville intensive, J. Geophys. Res.-Atmos., 103, 22281–22294, 1998.
Barratt, R. S.: The preparation of standard gas-mixtures – a review, Analyst, 106, 817–849, 1981.
de Gouw, J. A. and Warneke, C.: Measurements of volatile organic compounds in the earth's atmosphere using proton-transfer-reaction mass spectrometry, Mass Spectrom. Rev., 26, 223–257, 2007.
Dlugokencky, E. J., Myers, R. C., Lang, P. M., Masarie, K. A., Crotwell, A. M., Thoning, K. W., Hall, B. D., Elkins, J. W., and Steele, L. P.: Conversion of noaa atmospheric dry air CH4 mole fractions to a gravimetrically prepared standard scale, J. Geophys. Res.-Atmos., 110, D18306, https://doi.org/10.1029/2005jd006035, 2005.
Griffith, D. W. T.: Synthetic calibration and quantitative analysis of gas-phase ft-ir spectra, Appl. Spectrosc., 50, 59–70, 1996.
Hansel, A., Singer, W., Wisthaler, A., Schwarzmann, M., and Lindinger, W.: Energy dependencies of the proton transfer reactions \chem{H_3O^+}+\chem{CH_2O}$\nLeftrightarrow$\chem{CH_2OH^+}+H2O, Int. J. Mass Spectrom., 167, 697–703, 1997.
Lide, D. R.: CRC Handbook of Chemistry and Physics, CRC Press, Boca Raton, FL, 2005.
Maris, C., Chung, M. Y., Lueb, R., Krischke, U., Meller, R., Fox, M. J., and Paulson, S. E.: Development of instrumentation for simultaneous analysis of total non-methane organic carbon and volatile organic compounds in ambient air, ISI:000185829200010, S149–S158, 2003.
Naganowska-Nowak, A., Konieczka, P., Przyjazny, A., and Namiesnik, J.: Development of techniques of generation of gaseous standard mixtures, Crit. Rev. Anal. Chem., 35, 31–55, https://doi.org/10.1080/10408340590947916, 2005.
Namiesnik, J., Torres, L., Kozlowski, E., and Mathieu, J.: Evaluation of the suitability of selected porous polymers for preconcentation of volatile organic-compounds, J. Chromatogr., 208, 239–252, 1981.
Namiesnik, J.: Generation of standard gaseous-mixtures, J. Chromatogr., 300, 79–108, 1984.
Okeeffe, A. E. and Ortman, G. C.: Primary standards for trace gas analysis, Anal. Chem., 38, 760–763, 1966.
Possanzini, M., Di Palo, V., Brancaleoni, E., Frattoni, M., and Ciccioli, P.: Dynamic system for the calibration of semi-volatile carbonyl compounds in air, J. Chromatogr. A, 883, 171–183, 2000.
Rappengluck, B., Apel, E., Bauerfeind, M., Bottenheim, J., Brickell, P., Cavolka, P., Cech, J., Gatti, L., Hakola, H., Honzak, J., Junek, R., Martin, D., Noone, C., Plass-Dulmer, C., Travers, D., and Wang, D.: The first voc intercomparison exercise within the global atmosphere watch (gaw), Atmos. Environ., 40, 7508–7527, https://doi.org/10.1016/j.atmosenv.2006.07.016, 2006.
Roberts, J. M., Bertman, S. B., Jobson, T., Niki, H., and Tanner, R.: Measurement of total nonmethane organic carbon (\chem{C_y}): development and application at chebogue point, nova scotia, during the 1993 north atlantic regional experiment campaign, J. Geophys. Res.-Atmos., 103, 13581–13592, 1998.
Thompson, J. M. and Perry, D. B.: A new system of refillable and uniquely identifiable diffusion tubes for dynamically generating voc and svoc standard atmospheres at PPM and PPB concentrations for calibration of field and laboratory measurements, J. Environ. Monitor., 11, 1543–1544, https://doi.org/10.1039/b901954e, 2009.
Veres, P., Roberts, J. M., Warneke, C., Welsh-Bon, D., Zahniser, M., Herndon, S., Fall, R., and de Gouw, J.: Development of negative-ion proton-transfer chemical-ionization mass spectrometry (NI-PT-CIMS) for the measurement of gas-phase organic acids in the atmosphere, Int. J. Mass Spectrom., 274, 48–55, 2008.
Veres, P., Roberts, J. M., Burling, I. R., Warneke, C., Gouw, J. d., and Yokelson, R.: Measurement of gas-phase inorganic and organic acids from biomass fires by negatiove-ion proton-transfer chemical-ionization mass spectrometry (NI-PT-CIMS), JGR Atmospheres, in review, 2009.
Williams, J., Roberts, J. M., Bertman, S. B., Stroud, C. A., Fehsenfeld, F. C., Baumann, K., Buhr, M. P., Knapp, K., Murphy, P. C., Nowick, M., and Williams, E. J.: A method for the airborne measurement of PAN, PPN, and MPAN, J. Geophys. Res.-Atmos., 105, 28943–28960, 2000.
Yokelson, R. J., Karl, T., Artaxo, P., Blake, D. R., Christian, T. J., Griffith, D. W. T., Guenther, A., and Hao, W. M.: The Tropical Forest and Fire Emissions Experiment: overview and airborne fire emission factor measurements, Atmos. Chem. Phys., 7, 5175–5196, https://doi.org/10.5194/acp-7-5175-2007, 2007.
