Articles | Volume 6, issue 9
https://doi.org/10.5194/amt-6-2293-2013
© Author(s) 2013. 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-6-2293-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
05 Sep 2013
Research article |
| 05 Sep 2013
High-precision analysis of SF6 at ambient level
J. S. Lim
Korea Research Institute of Standards and Science (KRISS), Division of Metrology for Quality Life, P.O. Box 102, Yuseong, Daejeon, South Korea
D. M. Moon
Korea Research Institute of Standards and Science (KRISS), Division of Metrology for Quality Life, P.O. Box 102, Yuseong, Daejeon, South Korea
J. S. Kim
Korea Research Institute of Standards and Science (KRISS), Division of Metrology for Quality Life, P.O. Box 102, Yuseong, Daejeon, South Korea
W.-T. Yun
Climate Policy Division, Climate Science Bureau, Korea Meteorological Administration, 61 16-gil, Yeouidaebang-ro, Dongjak-gu, Seoul 156-720, South Korea
J. Lee
Korea Research Institute of Standards and Science (KRISS), Division of Metrology for Quality Life, P.O. Box 102, Yuseong, Daejeon, South Korea
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Beni Adi Trisna, Sang Woo Kim, Yong-Doo Kim, Miyeon Park, Seung-Nam Park, and Jeongsoon Lee
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-153, https://doi.org/10.5194/amt-2024-153, 2024
Preprint under review for AMT
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Manuscript presents a novel calibration method for measuring absorption cross sections (ACSs) of atmospheric gases using a compact UV-DOAS spectrometer. Combining precise lab measurements with advanced simulations, we accurately determined ACSs for various gases, including reactive ones, without costly reference materials. This approach lowers uncertainty, ensures traceability to standard units, and enhances measurement reliability, making it ideal for field applications.
Beni Adi Trisna, Seungnam Park, Injun Park, Jeongsoon Lee, and Jeong Sik Lim
Atmos. Chem. Phys., 23, 4489–4500, https://doi.org/10.5194/acp-23-4489-2023, https://doi.org/10.5194/acp-23-4489-2023, 2023
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An accurate estimate of radiative efficiency (RE) is substantial for an accurate assessment of global warming potential (GWP). In this study, we report accurate estimates of RE values of emerging greenhouse gases (GHGs) by using high-resolution Fourier transform infrared spectroscopy (FTIR). CF3OCFCF2 and CF3OCF2CF3 are reported for the first time. In addition, hidden errors in RE values of (CF3)2CFCN and CF3OCFCF2 in previous studies are pointed out.
Haeyoung Lee, Sang-Ok Han, Sang-Boom Ryoo, Jeong-Soon Lee, and Gang-Woong Lee
Atmos. Chem. Phys., 19, 2149–2163, https://doi.org/10.5194/acp-19-2149-2019, https://doi.org/10.5194/acp-19-2149-2019, 2019
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We introduced our identical systems, which were installed at three S. Korea stations, using CRDS and a drying system. The measurement uncertainty was ~ 0.11 ppm across the stations. CO2 observed in the west of S. Korea was very sensitive to East Asia (e.g., China), indicating that data include CO2 flux information from East Asia. Through long-term comparison to other East Asian stations, it was suggested that they could be affected not only by local vegetation but also by measurement quality.
Jeong Sik Lim, Miyeon Park, Jinbok Lee, and Jeongsoon Lee
Atmos. Meas. Tech., 10, 4613–4621, https://doi.org/10.5194/amt-10-4613-2017, https://doi.org/10.5194/amt-10-4613-2017, 2017
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Effect of background gas composition on the spectroscopic measurement of CO2 concentration at ambient levels has been investigated. The wavelength-scanned cavity ring-down spectroscopy was employed to explore the spectral line shape of CO2 at 1603 nm. It is revealed that the instrument response should be corrected with respect to a total pressure broadening coefficient given by a matrix composition. The correction method is validated by high accurate gravimetric standard gas mixture.
Related subject area
Subject: Gases | Technique: Laboratory Measurement | Topic: Validation and Intercomparisons
A nitrate ion chemical-ionization atmospheric-pressure-interface time-of-flight mass spectrometer (NO3− ToFCIMS) sensitivity study
Calibration of Hydroxyacetonitrile (HOCH2CN) and Methyl isocyanate (CH3NCO) Isomers using I- Chemical Ionization Mass Spectrometry (CIMS)
Two new 222Rn emanation sources – a comparison study
A traceable and continuous flow calibration method for gaseous elemental mercury at low ambient concentrations
Measurements of atmospheric C10–C15 biogenic volatile organic compounds (BVOCs) with sorbent tubes
Results of a long-term international comparison of greenhouse gas and isotope measurements at the Global Atmosphere Watch (GAW) Observatory in Alert, Nunavut, Canada
Colorimetric derivatization of ambient ammonia (NH3) for detection by long-path absorption photometry
Comparison of temperature-dependent calibration methods of an instrument to measure OH and HO2 radicals using laser-induced fluorescence spectroscopy
Controlled-release testing of the static chamber methodology for direct measurements of methane emissions
Development of an International System of Units (SI)-traceable transmission curve reference material to improve the quantitation and comparability of proton-transfer-reaction mass-spectrometry measurements
Reactive uptake coefficients for multiphase reactions determined by a dynamic chamber system
Influence of CO2 adsorption on cylinders and fractionation of CO2 and air during the preparation of a standard mixture
Detection of nitrous acid in the atmospheric simulation chamber SAPHIR using open-path incoherent broadband cavity-enhanced absorption spectroscopy and extractive long-path absorption photometry
Behavior of KCl sorbent traps and KCl trapping solutions used for atmospheric mercury speciation: stability and specificity
Intercomparison of O2 ∕ N2 ratio scales among AIST, NIES, TU, and SIO based on a round-robin exercise using gravimetric standard mixtures
Characterisation of gas reference materials for underpinning atmospheric measurements of stable isotopes of nitrous oxide
An indirect-calibration method for non-target quantification of trace gases applied to a time series of fourth-generation synthetic halocarbons at the Taunus Observatory (Germany)
Revision of the World Meteorological Organization Global Atmosphere Watch (WMO/GAW) CO2 calibration scale
Comparability of calibration strategies for measuring mercury concentrations in gas emission sources and the atmosphere
Characterizing water vapour concentration dependence of commercial cavity ring-down spectrometers for continuous on-site atmospheric water vapour isotope measurements in the tropics
Implementation of an incoherent broadband cavity-enhanced absorption spectroscopy technique in an atmospheric simulation chamber for in situ NO3 monitoring: characterization and validation for kinetic studies
A portable, robust, stable, and tunable calibration source for gas-phase nitrous acid (HONO)
Optimisation of a thermal desorption–gas chromatography–mass spectrometry method for the analysis of monoterpenes, sesquiterpenes and diterpenes
SIFT-MS optimization for atmospheric trace gas measurements at varying humidity
N2O isotopocule measurements using laser spectroscopy: analyzer characterization and intercomparison
An intercomparison of CH3O2 measurements by fluorescence assay by gas expansion and cavity ring-down spectroscopy within HIRAC (Highly Instrumented Reactor for Atmospheric Chemistry)
Photoacoustic measurement with infrared band-pass filters significantly overestimates NH3 emissions from cattle houses due to volatile organic compound (VOC) interferences
Isotopic characterization of nitrogen oxides (NOx), nitrous acid (HONO), and nitrate (pNO3−) from laboratory biomass burning during FIREX
A new laser-based and ultra-portable gas sensor for indoor and outdoor formaldehyde (HCHO) monitoring
Negligible influence of livestock contaminants and sampling system on ammonia measurements with cavity ring-down spectroscopy
Preparation of primary standard mixtures for atmospheric oxygen measurements with less than 1 µmol mol−1 uncertainty for oxygen molar fractions
The interference of tetrachloromethane in the measurement of benzene in the air by a gas chromatography–photoionisation detector (GC-PID)
Evaluation of cation exchange membrane performance under exposure to high Hg0 and HgBr2 concentrations
Gravimetrically prepared carbon dioxide standards in support of atmospheric research
The importance of cylinder passivation for preparation and long-term stability of multicomponent monoterpene primary reference materials
Dynamic–gravimetric preparation of metrologically traceable primary calibration standards for halogenated greenhouse gases
The water vapour self-continuum absorption in the infrared atmospheric windows: new laser measurements near 3.3 and 2.0 µm
Interlaboratory comparison of δ13C and δD measurements of atmospheric CH4 for combined use of data sets from different laboratories
Absolute, pressure-dependent validation of a calibration-free, airborne laser hygrometer transfer standard (SEALDH-II) from 5 to 1200 ppmv using a metrological humidity generator
An intercomparison of HO2 measurements by fluorescence assay by gas expansion and cavity ring-down spectroscopy within HIRAC (Highly Instrumented Reactor for Atmospheric Chemistry)
Abundances of isotopologues and calibration of CO2 greenhouse gas measurements
Intercomparison of two cavity ring-down spectroscopy analyzers for atmospheric 13CO2 ∕ 12CO2 measurement
Development and evaluation of a suite of isotope reference gases for methane in air
MIPAS database: new HNO3 line parameters at 7.6 µm validated with MIPAS satellite measurements
Challenges associated with the sampling and analysis of organosulfur compounds in air using real-time PTR-ToF-MS and offline GC-FID
Twin-cuvette measurement technique for investigation of dry deposition of O3 and PAN to plant leaves under controlled humidity conditions
Gas adsorption and desorption effects on cylinders and their importance for long-term gas records
HOx radical chemistry in oxidation flow reactors with low-pressure mercury lamps systematically examined by modeling
ACTRIS non-methane hydrocarbon intercomparison experiment in Europe to support WMO GAW and EMEP observation networks
A method for stable carbon isotope ratio and concentration measurements of ambient aromatic hydrocarbons
Stéphanie Alage, Vincent Michoud, Sergio Harb, Bénédicte Picquet-Varrault, Manuela Cirtog, Avinash Kumar, Matti Rissanen, and Christopher Cantrell
Atmos. Meas. Tech., 17, 4709–4724, https://doi.org/10.5194/amt-17-4709-2024, https://doi.org/10.5194/amt-17-4709-2024, 2024
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Calibration exercises are essential for determining the accuracy of instruments. We performed calibrations on a NO3¯ ToFCIMS instrument to determine its sensitivity and linearity for detecting various organic compounds. Our findings revealed significant variability, over several orders of magnitude, in the calibration factors obtained. The results suggest that relying on a single calibration factor from H2SO4 for the quantification of all compounds detected by this technique is not appropriate.
Zachary Finewax, Aparajeo Chattopadhyay, J. Andrew Neuman, James Roberts, and James Burkholder
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-94, https://doi.org/10.5194/amt-2024-94, 2024
Revised manuscript accepted for AMT
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This work provides a comprehensive sensitivity calibration of a chemical ionization instrument commonly used in field measurements for the measurement of the toxic isomers methyl isocyanate and hydroxyacetonitrile that are found in the atmosphere. The results from this work has demonstrated that the hydroyacetonitrile isomer was observed in previous field studies rather than the stated identification of methyl isocyanate.
Tanita J. Ballé, Stefan Röttger, Florian Mertes, Anja Honig, Petr Kovar, Petr P. S. Otáhal, and Annette Röttger
Atmos. Meas. Tech., 17, 2055–2065, https://doi.org/10.5194/amt-17-2055-2024, https://doi.org/10.5194/amt-17-2055-2024, 2024
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Over 50 % of naturally occurring radiation exposure is due to 222Rn (progenies), but traceability of measurements to the International System of Units (SI) is lacking. To address this, two new 222Rn sources were developed to be used as calibration standards for reference instruments. These sources were investigated by comparing their estimated calibration factors for one instrument. Despite the small differences derived, all uncertainties are well within the intended target uncertainty of 10 %.
Teodor D. Andron, Warren T. Corns, Igor Živković, Saeed Waqar Ali, Sreekanth Vijayakumaran Nair, and Milena Horvat
Atmos. Meas. Tech., 17, 1217–1228, https://doi.org/10.5194/amt-17-1217-2024, https://doi.org/10.5194/amt-17-1217-2024, 2024
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Atmospheric mercury monitoring is an important activity in order to model the global trajectory of this toxic element and to assess if certain areas are polluted or not in accordance to global guidelines. One of the analysers tested in this work is globally used in this regard due to its practicality compared with other devices. Because it is only calibrated by the manufacturer at very high concentrations, we wanted to see how it performs at ambient mercury concentrations.
Heidi Hellén, Toni Tykkä, Simon Schallhart, Evdokia Stratigou, Thérèse Salameh, and Maitane Iturrate-Garcia
Atmos. Meas. Tech., 17, 315–333, https://doi.org/10.5194/amt-17-315-2024, https://doi.org/10.5194/amt-17-315-2024, 2024
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Even though online measurements of biogenic volatile organic compounds (BVOCs) are becoming more common, the use of sorbent tubes is expected to continue because they offer greater spatial coverage and no infrastructure is required for sampling. In this study the sorbent tube sampling method was optimized and evaluated for the determination of BVOCs in gas-phase samples. Tenax TA sorbent tubes were found to be suitable for the quantitative measurements of C10–C15 BVOCs.
Douglas E. J. Worthy, Michele K. Rauh, Lin Huang, Felix R. Vogel, Alina Chivulescu, Kenneth A. Masarie, Ray L. Langenfelds, Paul B. Krummel, Colin E. Allison, Andrew M. Crotwell, Monica Madronich, Gabrielle Pétron, Ingeborg Levin, Samuel Hammer, Sylvia Michel, Michel Ramonet, Martina Schmidt, Armin Jordan, Heiko Moossen, Michael Rothe, Ralph Keeling, and Eric J. Morgan
Atmos. Meas. Tech., 16, 5909–5935, https://doi.org/10.5194/amt-16-5909-2023, https://doi.org/10.5194/amt-16-5909-2023, 2023
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Network compatibility is important for inferring greenhouse gas fluxes at global or regional scales. This study is the first assessment of the measurement agreement among seven individual programs within the World Meteorological Organization community. It compares co-located flask air measurements at the Alert Observatory in Canada over a 17-year period. The results provide stronger confidence in the uncertainty estimation while using those datasets in various data interpretation applications.
Shasha Tian, Kexin Zu, Huabin Dong, Limin Zeng, Keding Lu, and Qi Chen
Atmos. Meas. Tech., 16, 5525–5535, https://doi.org/10.5194/amt-16-5525-2023, https://doi.org/10.5194/amt-16-5525-2023, 2023
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We developed an online NH3 monitoring system based on a selective colorimetric reaction and a long-path absorption photometer (SAC-LOPAP), which can run statically for a long time and be applied to the continuous online measurement of low concentrations of ambient air by optimizing the reaction conditions, adding a constant-temperature module and liquid flow controller. It is well suited for the investigation of the NH3 budget for urban to rural conditions in China.
Frank A. F. Winiberg, William J. Warman, Charlotte A. Brumby, Graham Boustead, Iustinian G. Bejan, Thomas H. Speak, Dwayne E. Heard, Daniel Stone, and Paul W. Seakins
Atmos. Meas. Tech., 16, 4375–4390, https://doi.org/10.5194/amt-16-4375-2023, https://doi.org/10.5194/amt-16-4375-2023, 2023
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OH and HO2 are key reactive intermediates in the Earth's atmosphere. Accurate measurements in either the field or simulation chambers provide a good test for chemical mechanisms. Fluorescence techniques have the appropriate sensitivity for detection but require calibration. This paper compares different methods of calibration and specifically how calibration factors vary across a temperature range relevant to atmospheric and chamber determinations.
James P. Williams, Khalil El Hachem, and Mary Kang
Atmos. Meas. Tech., 16, 3421–3435, https://doi.org/10.5194/amt-16-3421-2023, https://doi.org/10.5194/amt-16-3421-2023, 2023
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Methane is powerful greenhouse gas; thus, to reduce methane emissions, it is important that the methods used to measure methane are tested and validated. The static chamber method is an enclosure-based technique that directly measures methane emissions; however, it has not been thoroughly tested for the new variety of methane sources that it is currently being used for. We find that the static chamber method can accurately measure methane emissions under a wide range of methane emission rates.
David R. Worton, Sergi Moreno, Kieran O'Daly, and Rupert Holzinger
Atmos. Meas. Tech., 16, 1061–1072, https://doi.org/10.5194/amt-16-1061-2023, https://doi.org/10.5194/amt-16-1061-2023, 2023
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Proton-transfer-reaction mass spectrometry is widely used in the environmental, health, and food and beverage sectors. As a result, there is a need for accurate and comparable measurements. In this work we have developed a 20-component gravimetrically prepared traceable primary reference material (gas standard in a high-pressure cylinder) to enable quantitative and comparable measurements. The accuracy of all components was better than 3 %–10 % with stabilities of better than 1–2 years.
Guo Li, Hang Su, Meng Li, Uwe Kuhn, Guangjie Zheng, Lei Han, Fengxia Bao, Ulrich Pöschl, and Yafang Cheng
Atmos. Meas. Tech., 15, 6433–6446, https://doi.org/10.5194/amt-15-6433-2022, https://doi.org/10.5194/amt-15-6433-2022, 2022
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A large fraction of previous work using dynamic flow chambers was to quantify gas exchange in terms of flux or deposition/emission rate. Here, we extended the usage of this technique to examine uptake kinetics on sample surfaces. The good performance of the chamber system was validated. This technique can be further used for liquid samples and real atmospheric aerosol samples without complicated coating procedures, which complements the existing techniques in atmospheric kinetic studies.
Nobuyuki Aoki, Shigeyuki Ishidoya, Shohei Murayama, and Nobuhiro Matsumoto
Atmos. Meas. Tech., 15, 5969–5983, https://doi.org/10.5194/amt-15-5969-2022, https://doi.org/10.5194/amt-15-5969-2022, 2022
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The CO2 concentration in a cylinder is affected by carbon dioxide (CO2) adsorption to a cylinder’s internal surface and fractionation of CO2 and air in the preparation of standard mixtures. We demonstrate that the effects make the CO2 molar fractions deviate in standard mixtures prepared by diluting pure CO2 with air three times. This means that CO2 standard gases are difficult to gravimetrically prepare through multistep dilution.
Sophie Dixneuf, Albert A. Ruth, Rolf Häseler, Theo Brauers, Franz Rohrer, and Hans-Peter Dorn
Atmos. Meas. Tech., 15, 945–964, https://doi.org/10.5194/amt-15-945-2022, https://doi.org/10.5194/amt-15-945-2022, 2022
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Atmospheric chambers, like SAPHIR in Jülich (Germany), are used to experimentally simulate specific atmospheric scenarios to improve our understanding of the complex chemical reactions occurring in our atmospheres. These facilities hence require cutting-edge gas-sensing capabilities to detect trace gases at the lowest level and in a short time. One important trace gas is HONO, for which we custom-built an optical sensing setup, capable of detecting one HONO molecule in ~40 billion in 1 min.
Jan Gačnik, Igor Živković, Sergio Ribeiro Guevara, Radojko Jaćimović, Jože Kotnik, Gianmarco De Feo, Matthew A. Dexter, Warren T. Corns, and Milena Horvat
Atmos. Meas. Tech., 14, 6619–6631, https://doi.org/10.5194/amt-14-6619-2021, https://doi.org/10.5194/amt-14-6619-2021, 2021
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Atmospheric mercury and knowledge of its transformations and processes are of great importance for lowering its anthropogenic emissions. To ensure that, it is crucial to have a tested and validated measurement procedure. Since this is not always the case, we performed experiments that provided insight into commonly used atmospheric mercury sampling methods. The results showed that some sampling methods are unsuitable, and some are useful if we consider the results obtained from this work.
Nobuyuki Aoki, Shigeyuki Ishidoya, Yasunori Tohjima, Shinji Morimoto, Ralph F. Keeling, Adam Cox, Shuichiro Takebayashi, and Shohei Murayama
Atmos. Meas. Tech., 14, 6181–6193, https://doi.org/10.5194/amt-14-6181-2021, https://doi.org/10.5194/amt-14-6181-2021, 2021
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Observing the minimal long-term change in atmospheric O2 molar fraction combined with CO2 observation enables us to estimate terrestrial biospheric and oceanic CO2 uptakes separately. In this study, we firstly identified the span offset between the laboratory O2 scales using our developed high-precision standard mixtures, suggesting that the result may allow us to estimate terrestrial biospheric and oceanic CO2 uptakes precisely.
Ruth E. Hill-Pearce, Aimee Hillier, Eric Mussell Webber, Kanokrat Charoenpornpukdee, Simon O'Doherty, Joachim Mohn, Christoph Zellweger, David R. Worton, and Paul J. Brewer
Atmos. Meas. Tech., 14, 5447–5458, https://doi.org/10.5194/amt-14-5447-2021, https://doi.org/10.5194/amt-14-5447-2021, 2021
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There is currently a need for gas reference materials with well-characterised delta values for monitoring N2O amount fractions. We present work towards the preparation of gas reference materials for calibration of in-field monitoring equipment, which target the WMO-GAW data quality objectives for comparability of amount fraction and demonstrate the stability of δ15Nα, δ15Nβ and δ18O values with pressure and effects of cylinder passivation.
Fides Lefrancois, Markus Jesswein, Markus Thoma, Andreas Engel, Kieran Stanley, and Tanja Schuck
Atmos. Meas. Tech., 14, 4669–4687, https://doi.org/10.5194/amt-14-4669-2021, https://doi.org/10.5194/amt-14-4669-2021, 2021
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Synthetic halocarbons can contribute to stratospheric ozone depletion or to climate change. In many applications they have been replaced over the last years. The presented non-target analysis shows an application approach to quantify those replacements retrospectively, using recorded data of air measurements with gas chromatography coupled to time-of-flight mass spectrometry. We focus on the retrospective analysis of the fourth-generation halocarbons, detected at Taunus Observatory in Germany.
Bradley D. Hall, Andrew M. Crotwell, Duane R. Kitzis, Thomas Mefford, Benjamin R. Miller, Michael F. Schibig, and Pieter P. Tans
Atmos. Meas. Tech., 14, 3015–3032, https://doi.org/10.5194/amt-14-3015-2021, https://doi.org/10.5194/amt-14-3015-2021, 2021
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We have recently revised the carbon dioxide calibration scale used by numerous laboratories that measure atmospheric CO2. The revision follows from an improved understanding of the manometric method used to determine the absolute amount of CO2 in an atmospheric air sample. The new scale is 0.18 μmol mol−1 (ppm) greater than the previous scale at 400 ppm CO2. While this difference is small in relative terms (0.045 %), it is significant in terms of atmospheric monitoring.
Iris de Krom, Wijnand Bavius, Ruben Ziel, Elizabeth A. McGhee, Richard J. C. Brown, Igor Živković, Jan Gačnik, Vesna Fajon, Jože Kotnik, Milena Horvat, and Hugo Ent
Atmos. Meas. Tech., 14, 2317–2326, https://doi.org/10.5194/amt-14-2317-2021, https://doi.org/10.5194/amt-14-2317-2021, 2021
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To demonstrate the robustness and comparability of the novel primary mercury gas standard, the results of comparisons are presented with current calibration methods maintained, using the bell jar in combination with the Dumarey equation or NIST liquid standard reference material. The results show that the primary standard and the NIST reference material are comparable, whereas a difference of −8 % exists between results traceable to the primary standard and the Dumarey equation.
Shujiro Komiya, Fumiyoshi Kondo, Heiko Moossen, Thomas Seifert, Uwe Schultz, Heike Geilmann, David Walter, and Jost V. Lavric
Atmos. Meas. Tech., 14, 1439–1455, https://doi.org/10.5194/amt-14-1439-2021, https://doi.org/10.5194/amt-14-1439-2021, 2021
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The Amazon basin influences the atmospheric and hydrological cycles on local to global scales. To better understand how, we plan to perform continuous on-site measurements of the stable isotope composition of atmospheric water vapour. For making accurate on-site observations possible, we have investigated the performance of two commercial analysers and determined the best calibration strategy. Well calibrated, both analysers will allow us to record natural signals in the Amazon rainforest.
Axel Fouqueau, Manuela Cirtog, Mathieu Cazaunau, Edouard Pangui, Pascal Zapf, Guillaume Siour, Xavier Landsheere, Guillaume Méjean, Daniele Romanini, and Bénédicte Picquet-Varrault
Atmos. Meas. Tech., 13, 6311–6323, https://doi.org/10.5194/amt-13-6311-2020, https://doi.org/10.5194/amt-13-6311-2020, 2020
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An incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS) technique has been developed for the in situ monitoring of NO3 radicals in the CSA simulation chamber at LISA. The optical cavity allows a high sensitivity for NO3 detection up to 6 ppt for an integration time of 10 s. The technique is now fully operational and can be used to determine rate constants for fast reactions involving complex volatile organic compounds (with rate constants up to 10−10 cm3 molecule−1 s−1).
Melodie Lao, Leigh R. Crilley, Leyla Salehpoor, Teles C. Furlani, Ilann Bourgeois, J. Andrew Neuman, Andrew W. Rollins, Patrick R. Veres, Rebecca A. Washenfelder, Caroline C. Womack, Cora J. Young, and Trevor C. VandenBoer
Atmos. Meas. Tech., 13, 5873–5890, https://doi.org/10.5194/amt-13-5873-2020, https://doi.org/10.5194/amt-13-5873-2020, 2020
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Nitrous acid (HONO) is a key intermediate in the generation of oxidants and fate of nitrogen oxides in the atmosphere. High-purity calibration sources that produce stable atmospherically relevant levels under field conditions have not been made to date, reducing measurement accuracy. In this study a simple salt-coated tube humidified with water vapor is demonstrated to produce pure stable low levels of HONO, with modifications allowing the generation of higher amounts.
Aku Helin, Hannele Hakola, and Heidi Hellén
Atmos. Meas. Tech., 13, 3543–3560, https://doi.org/10.5194/amt-13-3543-2020, https://doi.org/10.5194/amt-13-3543-2020, 2020
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A thermal desorption–gas chromatography–mass spectrometry method following sorbent tube sampling was developed for the determination of terpenes in gas-phase samples. The main focus was on the analysis of diterpenes, which have been limited in study in gas-phase samples. The analytical figures of merit were fit for purpose (e.g. quantitation limits <10 pptv and reproducibility <10 % for terpenes). Diterpenes could be detected and identified in emissions from spruce and pine samples.
Ann-Sophie Lehnert, Thomas Behrendt, Alexander Ruecker, Georg Pohnert, and Susan E. Trumbore
Atmos. Meas. Tech., 13, 3507–3520, https://doi.org/10.5194/amt-13-3507-2020, https://doi.org/10.5194/amt-13-3507-2020, 2020
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Volatile organic compounds (VOCs) like scents can appear and disappear quickly. For example, when a bug starts on a tree, the tree releases VOCs that warn the trees around him. Thus, one needs instruments measuring their concentration in real time and identify which VOC is measured. In our study, we compared two instruments doing that, PTR-MS and SIFT-MS. Both work similarly, but we found that the PTR-MS can measure lower concentrations, but the SIFT-MS can identify VOCs better.
Stephen J. Harris, Jesper Liisberg, Longlong Xia, Jing Wei, Kerstin Zeyer, Longfei Yu, Matti Barthel, Benjamin Wolf, Bryce F. J. Kelly, Dioni I. Cendón, Thomas Blunier, Johan Six, and Joachim Mohn
Atmos. Meas. Tech., 13, 2797–2831, https://doi.org/10.5194/amt-13-2797-2020, https://doi.org/10.5194/amt-13-2797-2020, 2020
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The latest commercial laser spectrometers have the potential to revolutionize N2O isotope analysis. However, to do so, they must be able to produce trustworthy data. Here, we test the performance of widely used laser spectrometers for ambient air applications and identify instrument-specific dependencies on gas matrix and trace gas concentrations. We then provide a calibration workflow to facilitate the operation of these instruments in order to generate reproducible and accurate data.
Lavinia Onel, Alexander Brennan, Michele Gianella, James Hooper, Nicole Ng, Gus Hancock, Lisa Whalley, Paul W. Seakins, Grant A. D. Ritchie, and Dwayne E. Heard
Atmos. Meas. Tech., 13, 2441–2456, https://doi.org/10.5194/amt-13-2441-2020, https://doi.org/10.5194/amt-13-2441-2020, 2020
Dezhao Liu, Li Rong, Jesper Kamp, Xianwang Kong, Anders Peter S. Adamsen, Albarune Chowdhury, and Anders Feilberg
Atmos. Meas. Tech., 13, 259–272, https://doi.org/10.5194/amt-13-259-2020, https://doi.org/10.5194/amt-13-259-2020, 2020
Jiajue Chai, David J. Miller, Eric Scheuer, Jack Dibb, Vanessa Selimovic, Robert Yokelson, Kyle J. Zarzana, Steven S. Brown, Abigail R. Koss, Carsten Warneke, and Meredith Hastings
Atmos. Meas. Tech., 12, 6303–6317, https://doi.org/10.5194/amt-12-6303-2019, https://doi.org/10.5194/amt-12-6303-2019, 2019
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Isotopic analysis offers a potential tool to distinguish between sources and interpret transformation pathways of atmospheric species. We applied recently developed techniques in our lab to characterize the isotopic composition of reactive nitrogen species (NOx, HONO, HNO3, pNO3-) in fresh biomass burning emissions. Intercomparison with other techniques confirms the suitability of our methods, allowing for future applications of our techniques in a variety of environments.
Joshua D. Shutter, Norton T. Allen, Thomas F. Hanisco, Glenn M. Wolfe, Jason M. St. Clair, and Frank N. Keutsch
Atmos. Meas. Tech., 12, 6079–6089, https://doi.org/10.5194/amt-12-6079-2019, https://doi.org/10.5194/amt-12-6079-2019, 2019
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A new mid-infrared and ultra-portable formaldehyde (HCHO) sensor from Aeris Technologies is characterized and evaluated against well-established laser-induced fluorescence (LIF) instrumentation. The Aeris sensor displays linear behavior (R squared > 0.94) and shows good agreement with LIF instruments. While the compact sensor is not currently a replacement for the most sensitive research-grade instrumentation available, its sub-ppbv precision is sufficient for indoor and outdoor HCHO monitoring.
Jesper Nørlem Kamp, Albarune Chowdhury, Anders Peter S. Adamsen, and Anders Feilberg
Atmos. Meas. Tech., 12, 2837–2850, https://doi.org/10.5194/amt-12-2837-2019, https://doi.org/10.5194/amt-12-2837-2019, 2019
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We tested the performance of a cavity ring-down spectroscopy (CRDS) instrument from Picarro for measuring ammonia. Interference tests with 10 volatile organic compounds (VOCs) were conducted to find potential interference of these VOCs. Calibrations show excellent linearity over a large dynamic range of NH3 concentrations. There is negligible interference from humidity and few of the tested VOCs. Overall, the CRDS system performs well with only negligible influence from other compounds.
Nobuyuki Aoki, Shigeyuki Ishidoya, Nobuhiro Matsumoto, Takuro Watanabe, Takuya Shimosaka, and Shohei Murayama
Atmos. Meas. Tech., 12, 2631–2646, https://doi.org/10.5194/amt-12-2631-2019, https://doi.org/10.5194/amt-12-2631-2019, 2019
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Observation of atmospheric O2 requires highly precise standard gas mixtures with uncertainty of less than 1 ppm for the O2 mole fraction or 5 per meg for O2 / N2. The uncertainty had not been achieved due unknown uncertainty factors in mass determination of the filled source gases. We first developed the primary standard mixtures with 1 ppm for the O2 mole fraction or 5 per meg by identifying and reducing the unknown uncertainty factors.
Cristina Romero-Trigueros, María Esther González, Marta Doval Miñarro, and Enrique González Ferradás
Atmos. Meas. Tech., 12, 1685–1695, https://doi.org/10.5194/amt-12-1685-2019, https://doi.org/10.5194/amt-12-1685-2019, 2019
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Determining benzene in ambient air is mandatory in the European Union. The reference measuring technique is by gas chromatography (GC), and a photometric ionisation detector is recommended. This study shows that the simultaneous presence of benzene and tetrachloromethane causes a significant decrease in GC–photoionisation detector (GC-PID) readings. Given the importance of this behaviour, a possible mechanism was proposed. This study highlights the uncertainty of measuring benzene with a GC-PID.
Matthieu B. Miller, Sarrah M. Dunham-Cheatham, Mae Sexauer Gustin, and Grant C. Edwards
Atmos. Meas. Tech., 12, 1207–1217, https://doi.org/10.5194/amt-12-1207-2019, https://doi.org/10.5194/amt-12-1207-2019, 2019
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This study was undertaken to demonstrate that a cation exchange membrane (CEM) material used for sampling reactive mercury (RM) does not possess an inherent tendency to collect gaseous elemental mercury (GEM). Using a custom-built mercury vapor permeation system, we found that the CEM material has a very small GEM uptake of approximately 0.004 %, too small to create a significant artifact. We also found that a representative RM compound was collected by the CEM material with high efficiency.
Bradley D. Hall, Andrew M. Crotwell, Benjamin R. Miller, Michael Schibig, and James W. Elkins
Atmos. Meas. Tech., 12, 517–524, https://doi.org/10.5194/amt-12-517-2019, https://doi.org/10.5194/amt-12-517-2019, 2019
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We have used a one-step method for gravimetric preparation of CO2-in-air standards in aluminum cylinders. We consider both adsorption to stainless steel surfaces used in the transfer of highly pure CO2 and adsorption of CO2 to cylinder walls. This work compliments ongoing efforts to support atmospheric monitoring of CO2.
Nicholas D. C. Allen, David R. Worton, Paul J. Brewer, Celine Pascale, and Bernhard Niederhauser
Atmos. Meas. Tech., 11, 6429–6438, https://doi.org/10.5194/amt-11-6429-2018, https://doi.org/10.5194/amt-11-6429-2018, 2018
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This paper investigates the stability of trace level static terpene primary reference materials (PRMs) and how the choice of passivation affects this process. For the first time, sampling canisters that can be used in the field are tested and demonstrated to be suitable for terpene mixtures. The PRMs were compared against a novel dynamic generator system based on dilution of pure limonene vapour emitted from a permeation tube. The effect of cylinder pressure and decanting are also investigated.
Myriam Guillevic, Martin K. Vollmer, Simon A. Wyss, Daiana Leuenberger, Andreas Ackermann, Céline Pascale, Bernhard Niederhauser, and Stefan Reimann
Atmos. Meas. Tech., 11, 3351–3372, https://doi.org/10.5194/amt-11-3351-2018, https://doi.org/10.5194/amt-11-3351-2018, 2018
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We present new primary calibration scales for five halogenated greenhouse gases. The preparation method, newly applied to halocarbons, is dynamic and gravimetric
and allows the generation of reference gas mixtures at near-ambient levels (pmol mol−1). Each prepared molar fraction is traceable to the
realisation of SI units (International System of Units) and is assigned an uncertainty estimate following international guidelines.
Loic Lechevallier, Semen Vasilchenko, Roberto Grilli, Didier Mondelain, Daniele Romanini, and Alain Campargue
Atmos. Meas. Tech., 11, 2159–2171, https://doi.org/10.5194/amt-11-2159-2018, https://doi.org/10.5194/amt-11-2159-2018, 2018
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The amplitude, the temperature dependence, and the physical origin of the water vapour absorption continuum are a long standing issue in molecular spectroscopy with a direct impact in atmospheric and planetary sciences. Using highly sensitive laser spectrometers, the water self continuum has been determined with unprecedented sensitivity in infrared atmospheric transparency windows.
Taku Umezawa, Carl A. M. Brenninkmeijer, Thomas Röckmann, Carina van der Veen, Stanley C. Tyler, Ryo Fujita, Shinji Morimoto, Shuji Aoki, Todd Sowers, Jochen Schmitt, Michael Bock, Jonas Beck, Hubertus Fischer, Sylvia E. Michel, Bruce H. Vaughn, John B. Miller, James W. C. White, Gordon Brailsford, Hinrich Schaefer, Peter Sperlich, Willi A. Brand, Michael Rothe, Thomas Blunier, David Lowry, Rebecca E. Fisher, Euan G. Nisbet, Andrew L. Rice, Peter Bergamaschi, Cordelia Veidt, and Ingeborg Levin
Atmos. Meas. Tech., 11, 1207–1231, https://doi.org/10.5194/amt-11-1207-2018, https://doi.org/10.5194/amt-11-1207-2018, 2018
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Isotope measurements are useful for separating different methane sources. However, the lack of widely accepted standards and calibration methods for stable carbon and hydrogen isotopic ratios of methane in air has caused significant measurement offsets among laboratories. We conducted worldwide interlaboratory comparisons, surveyed the literature and assessed them systematically. This study may be of help in future attempts to harmonize data sets of isotopic composition of atmospheric methane.
Bernhard Buchholz and Volker Ebert
Atmos. Meas. Tech., 11, 459–471, https://doi.org/10.5194/amt-11-459-2018, https://doi.org/10.5194/amt-11-459-2018, 2018
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This paper describes the absolute validation of the novel, calibration-free SEALDH-II hygrometer at a traceable humidity generator. During 23 days of permanent operation, 15 H2O mole fractions levels (5–1200 ppmv) at 6 gas pressures (65–950 hPa) were validated. With this validation, SEALDH-II is the first metrologically validated humidity transfer standard which links several scientific airborne and laboratory measurement campaigns to the international metrological water vapor scale.
Lavinia Onel, Alexander Brennan, Michele Gianella, Grace Ronnie, Ana Lawry Aguila, Gus Hancock, Lisa Whalley, Paul W. Seakins, Grant A. D. Ritchie, and Dwayne E. Heard
Atmos. Meas. Tech., 10, 4877–4894, https://doi.org/10.5194/amt-10-4877-2017, https://doi.org/10.5194/amt-10-4877-2017, 2017
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Hydroperoxy (HO2) radicals are key intermediates participating in a rapid chemical cycling at the centre of the tropospheric oxidation. Fluorescence assay by gas expansion (FAGE) technique is the most commonly used for the HO2 measurements in the atmosphere. However, FAGE is an indirect technique, requiring calibration. This work finds a good agreement between the indirect FAGE method and the direct cavity ring-down spectroscopy method and hence validates FAGE and the FAGE calibration method.
Pieter P. Tans, Andrew M. Crotwell, and Kirk W. Thoning
Atmos. Meas. Tech., 10, 2669–2685, https://doi.org/10.5194/amt-10-2669-2017, https://doi.org/10.5194/amt-10-2669-2017, 2017
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We describe a new CO2 calibration system for the Central Calibration Laboratory of the World Meteorological Organization Global Atmosphere Watch program. The system uses two laser spectroscopic instruments to measure the three major CO2 isotopologues individually. We account for isotopic differences between standards in the calibration hierarchy when assigning CO2 mole fraction, eliminating bias due to variations in the isotopic composition.
Jiaping Pang, Xuefa Wen, Xiaomin Sun, and Kuan Huang
Atmos. Meas. Tech., 9, 3879–3891, https://doi.org/10.5194/amt-9-3879-2016, https://doi.org/10.5194/amt-9-3879-2016, 2016
Peter Sperlich, Nelly A. M. Uitslag, Jürgen M. Richter, Michael Rothe, Heike Geilmann, Carina van der Veen, Thomas Röckmann, Thomas Blunier, and Willi A. Brand
Atmos. Meas. Tech., 9, 3717–3737, https://doi.org/10.5194/amt-9-3717-2016, https://doi.org/10.5194/amt-9-3717-2016, 2016
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Isotope measurements in atmospheric CH4 are performed since more than 3 decades. However, standard gases to harmonize global measurements are not available to this day. We designed two methods to calibrate a suite of 8 CH4 gases with a wide range in isotopic composition to the VPDB and VSMOW scales with high precision and accuracy. Synthetic air mixtures with ~2 ppm of calibrated CH4 can be provided to the community by the ISOLAB of the Max Planck Institute for Biogeochemistry in Jena, Germany.
Agnès Perrin, Jean-Marie Flaud, Marco Ridolfi, Jean Vander Auwera, and Massimo Carlotti
Atmos. Meas. Tech., 9, 2067–2076, https://doi.org/10.5194/amt-9-2067-2016, https://doi.org/10.5194/amt-9-2067-2016, 2016
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Improved line positions and intensities have been generated for the 7.6 µm spectral region of nitric acid, relying on a recent laboratory reinvestigation and comparisons of HNO3 volume mixing ratios retrieved from Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) radiances in the 11 and 7.6 µm regions. The much improved consistency of line intensities in both regions will make it possible to use them simultaneously to retrieve atmospheric HNO3.
Véronique Perraud, Simone Meinardi, Donald R. Blake, and Barbara J. Finlayson-Pitts
Atmos. Meas. Tech., 9, 1325–1340, https://doi.org/10.5194/amt-9-1325-2016, https://doi.org/10.5194/amt-9-1325-2016, 2016
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Gas phase organosulfur compounds in air serve as precursors of particles which impact human health, visibility, and climate. We compare here two different approaches to measuring these compounds, one an online mass spectrometry technique and the other canister sampling followed by offline analysis by gas chromatography. We show that each approach has its own advantages and limitations in measuring these compounds in complex mixtures, including some artifacts due to reactions on surfaces.
Shang Sun, Alexander Moravek, Lisa von der Heyden, Andreas Held, Matthias Sörgel, and Jürgen Kesselmeier
Atmos. Meas. Tech., 9, 599–617, https://doi.org/10.5194/amt-9-599-2016, https://doi.org/10.5194/amt-9-599-2016, 2016
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We present a dynamic twin-cuvette system for quantifying the trace gas exchange fluxes between plants and the atmosphere under controlled temperature, light, and humidity conditions. We found out that at a relative humidity of 40 %, the deposition velocity ratio of O3 and PAN was determined to be 0.45. At that humidity, the O3-deposition to the plant leaves was found to be only controlled by leaf stomata. For PAN, an additional resistance inhibited the uptake of PAN by the leaves.
M. C. Leuenberger, M. F. Schibig, and P. Nyfeler
Atmos. Meas. Tech., 8, 5289–5299, https://doi.org/10.5194/amt-8-5289-2015, https://doi.org/10.5194/amt-8-5289-2015, 2015
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Adsorption/desorption effects of trace gases in gas cylinders were investigated. Our measurements indicate a rather strong effect on steel cylinders for CO2 that becomes easily visible through enhanced concentrations for low (<20 bars) gas pressure. Much smaller effects are observed for CO and CH4. Significantly smaller effects are measured for all gas species investigated on aluminium cylinders. Careful selection of gas cylinders for high-precision calibration purposes is recommended.
Z. Peng, D. A. Day, H. Stark, R. Li, J. Lee-Taylor, B. B. Palm, W. H. Brune, and J. L. Jimenez
Atmos. Meas. Tech., 8, 4863–4890, https://doi.org/10.5194/amt-8-4863-2015, https://doi.org/10.5194/amt-8-4863-2015, 2015
C. C. Hoerger, A. Claude, C. Plass-Duelmer, S. Reimann, E. Eckart, R. Steinbrecher, J. Aalto, J. Arduini, N. Bonnaire, J. N. Cape, A. Colomb, R. Connolly, J. Diskova, P. Dumitrean, C. Ehlers, V. Gros, H. Hakola, M. Hill, J. R. Hopkins, J. Jäger, R. Junek, M. K. Kajos, D. Klemp, M. Leuchner, A. C. Lewis, N. Locoge, M. Maione, D. Martin, K. Michl, E. Nemitz, S. O'Doherty, P. Pérez Ballesta, T. M. Ruuskanen, S. Sauvage, N. Schmidbauer, T. G. Spain, E. Straube, M. Vana, M. K. Vollmer, R. Wegener, and A. Wenger
Atmos. Meas. Tech., 8, 2715–2736, https://doi.org/10.5194/amt-8-2715-2015, https://doi.org/10.5194/amt-8-2715-2015, 2015
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The performance of 20 European laboratories involved in long-term non-methane hydrocarbon (NMHC) measurements was assessed with respect to ACTRIS and GAW data quality objectives. The participants were asked to measure both a 30-component NMHC mixture in nitrogen and whole air. The NMHCs were analysed either by GC-FID or GC-MS. Most systems performed well for the NMHC in nitrogen, whereas in air more scatter was observed. Reasons for this are explained in the paper.
A. Kornilova, S. Moukhtar, M. Saccon, L. Huang, W. Zhang, and J. Rudolph
Atmos. Meas. Tech., 8, 2301–2313, https://doi.org/10.5194/amt-8-2301-2015, https://doi.org/10.5194/amt-8-2301-2015, 2015
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A technique for compound specific analysis of stable carbon isotope ratios and concentration of ambient volatile organic compounds (VOC) is presented. It is based on selective VOC sampling onto adsorbent filled cartridges. Examples of measurements conducted demonstrate that the ability to make accurate measurements in air with low VOC mixing ratios is important to avoid bias from an overrepresentation of samples that are strongly impacted by recent emissions.
Cited articles
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., 110, D18306, https://doi.org/10.1029/2005JD006035, 2005.
GAW Report No. 172: Global Atmosphere Watch (GAW) Strategic Plan: 2008–2015, WMO, 2009.
GAW Report No. 186: 14th WMO/IAEA Meeting of Exerts on Carbon Dioxide, Other Greenhouse Gases and Related Tracers Measurement Techniques, WMO, 2009.
Hall, B. D., Dutton, G. S., Mondeel, D. J., Nance, J. D., Rigby, M., Butler, J. H., Moore, F. L., Hurst, D. F., and Elkins, J. W.: Improving measurements of SF6 for the study of atmospheric transport and emissions, Atmos. Meas. Tech., 4, 2441–2451, https://doi.org/10.5194/amt-4-2441-2011, 2011.
HATS (The Halocarbons and other Atmospheric Trace Species) group web site: available at: http://www.esrl.noaa.gov/gmd/hats/combined/SF6.html (last access: 15 June 2013), 2013.
ISO 6142: Gas analysis – Preparation of calibration gas mixture – Gravimetric method, 2001.
Lee, J., Lee, J., Moon, D., Kim, J. S., Wessel, R., Aoki, N., Kato, K., Guenther, F., Rhoderick, G., Konopelko, L. A., Han, Q., and Hall, B.: Final report on international comparison CCQM-K68: Nitrous oxide in synthetic air, Metrologia, 48, 08004, https://doi.org/10.1088/0026-1394/48/1A/08004, 2011.
Min, D., Kang, N., Moon, D. M., Lee, J. B., Lee, D. S., and Kim, J. S.: Effect of variation in argon content of calibration gases on determination of atmospheric carbon dioxide, Talanta, 80, 422–427, 2009.
Rigby, M., Mühle, J., Miller, B. R., Prinn, R. G., Krummel, P. B., Steele, L. P., Fraser, P. J., Salameh, P. K., Harth, C. M., Weiss, R. F., Greally, B. R., O'Doherty, S., Simmonds, P. G., Vollmer, M. K., Reimann, S., Kim, J., Kim, K.-R., Wang, H. J., Olivier, J. G. J., Dlugokencky, E. J., Dutton, G. S., Hall, B. D., and Elkins, J. W.: History of atmospheric SF6 from 1973 to 2008, Atmos. Chem. Phys., 10, 10305–10320, https://doi.org/10.5194/acp-10-10305-2010, 2010.
van der Veen, A. M. H., Brinkmann, F. N. C., Amautovic, M., Besley, L., Hans-Joachim H., Esteban, T. L., Sega, M., Kato, K., Kim, J. S., Castorena, A. P., Rakowska, A., Milton, M. J. T., Guenther, F. R., Francey, R., and Dlugokencky, E.: International comparison CCQM-P41 greenhouse gases. 1. Measurement capability, Metrologia, 44, 08002, https://doi.org/10.1088/0026-1394/44/1A/08002, 2007.
Wessel, R. M., van der Veen, A. M. H., Ziel, P. R., Steele, P., Langenfelds, R., van der Schoot, M., Smeulders, D., Besley, L., da Cunha, V. S., Zhou, Z., Qiao, H., Heine, H. J., Martin, B., Macé, T., Gupta, P. K., di Meane, E. A., Sega, M., Rolle, F., Maruyama, M., Kato, K., Matsumoto, N., Kim, J. S., Moon, D. M., Lee, J. B., Murillo, F. R., Nambo, C. R., Caballero, V. M. S., Salas, M. J. A., Castorena, A. P., Konopelko, L. A., Kustikov, Y. A., Kolobova, A. V., Pankratov, V. V., Efremova, O. V., Musil, S., Chromek, F., Valkova, M., Milton, M. J. T., Vargha, G., Guenther, F., Miller, W. R., Botha, A., Tshilongo, J., Mokgoro, I. S., and Leshabane, N.: International Comparison CCQM K52 – Carbon dioxide in Synthetic Air, Metrologia, 45, 08011, https://doi.org/10.1088/0026-1394/45/1A/08011, 2008.
