Articles | Volume 3, issue 6
https://doi.org/10.5194/amt-3-1519-2010
© 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-3-1519-2010
© Author(s) 2010. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
08 Nov 2010
Research article |
| 08 Nov 2010
Field intercomparison of two optical analyzers for CH4 eddy covariance flux measurements
B. Tuzson
Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Air Pollution and Environmental Technology, Überlandstr. 129, 8600 Dübendorf, Switzerland
R. V. Hiller
ETH Zurich, Institute of Plant, Animal and Agroecosystem Sciences, Universitätsstr. 2, 8092 Zürich, Switzerland
K. Zeyer
Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Air Pollution and Environmental Technology, Überlandstr. 129, 8600 Dübendorf, Switzerland
W. Eugster
ETH Zurich, Institute of Plant, Animal and Agroecosystem Sciences, Universitätsstr. 2, 8092 Zürich, Switzerland
A. Neftel
Agroscope Reckenholz-Tänikon Research Station ART, Reckenholzstr. 191, 8046 Zürich, Switzerland
C. Ammann
Agroscope Reckenholz-Tänikon Research Station ART, Reckenholzstr. 191, 8046 Zürich, Switzerland
L. Emmenegger
Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Air Pollution and Environmental Technology, Überlandstr. 129, 8600 Dübendorf, Switzerland
Related subject area
Subject: Gases | Technique: In Situ Measurement | Topic: Instruments and Platforms
A modular field system for near-surface, vertical profiling of the atmospheric composition in harsh environments using cavity ring-down spectroscopy
Field comparison of two novel open-path instruments that measure dry deposition and emission of ammonia using flux-gradient and eddy covariance methods
Development of multi-channel whole-air sampling equipment onboard an unmanned aerial vehicle for investigating volatile organic compounds' vertical distribution in the planetary boundary layer
Electrochemical sensors on board a Zeppelin NT: in-flight evaluation of low-cost trace gas measurements
Evaluating the performance of a Picarro G2207-i analyser for high-precision atmospheric O2 measurements
Airborne flux measurements of ammonia over the southern Great Plains using chemical ionization mass spectrometry
Optical receiver characterizations and corrections for ground-based and airborne measurements of spectral actinic flux densities
Development and validation of a new in situ technique to measure total gaseous chlorine in air
True eddy accumulation – Part 1: Solutions to the problem of non-vanishing mean vertical wind velocity
True eddy accumulation – Part 2: Theory and experiment of the short-time eddy accumulation method
Chemical ionization mass spectrometry utilizing ammonium ions (NH4+ CIMS) for measurements of organic compounds in the atmosphere
Direct measurement of N2O5 heterogeneous uptake coefficients on ambient aerosols via an aerosol flow tube system: design, characterization and performance
Online measurements of cycloalkanes based on NO+ chemical ionization in proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS)
Intercomparison of in situ measurements of ambient NH3: instrument performance and application under field conditions
A lightweight broadband cavity-enhanced spectrometer for NO2 measurement on uncrewed aerial vehicles
A novel spectroscopic approach and sampling method for ambient hydrogen chloride detection: HCl-TILDAS
On the development of a new prototype PTR-ToF-MS instrument and its application to the detection of atmospheric amines
New methods for the calibration of optical resonators: Integrated Calibration by means of Optical Modulation (ICOM) and Narrow Band Cavity ring-down (NB-CRD)
Low-complexity methods to mitigate the impact of environmental variables on low-cost UAS-based atmospheric carbon dioxide measurements
Comparison of airborne measurements of NO, NO2, HONO, NOy, and CO during FIREX-AQ
Short-term variability of atmospheric helium revealed through a cryo-enrichment method
Development of an automated pump efficiency measuring system for ozonesonde utilizing the airbag type flowmeter
Development of a broadband cavity-enhanced absorption spectrometer for simultaneous measurements of ambient NO3, NO2, and H2O
Improvements of a low-cost CO2 commercial nondispersive near-infrared (NDIR) sensor for unmanned aerial vehicle (UAV) atmospheric mapping applications
Development and testing of a novel sulfur dioxide sonde
Temperature-dependent sensitivity of iodide chemical ionization mass spectrometers
A quadcopter unmanned aerial system (UAS)-based methodology for measuring biomass burning emission factors
Air quality observations onboard commercial and targeted Zeppelin flights in Germany – a platform for high-resolution trace-gas and aerosol measurements within the planetary boundary layer
Performance of open-path lasers and Fourier transform infrared spectroscopic systems in agriculture emissions research
Metrology for low-cost CO2 sensors applications: the case of a steady-state through-flow (SS-TF) chamber for CO2 fluxes observations
A relaxed eddy accumulation (REA) LOPAP system for flux measurements of nitrous acid (HONO)
Fill dynamics and sample mixing in the AirCore
IRIS analyser assessment reveals sub-hourly variability of isotope ratios in carbon dioxide at Baring Head, New Zealand's atmospheric observatory in the Southern Ocean
A versatile vacuum ultraviolet ion source for reduced pressure bipolar chemical ionization mass spectrometry
Design and characterization of a semi-open dynamic chamber for measuring biogenic volatile organic compound (BVOC) emissions from plants
First eddy covariance flux measurements of semi-volatile organic compounds with the PTR3-TOF-MS
An unmanned aerial vehicle sampling platform for atmospheric water vapor isotopes in polar environments
Novel approach to observing system simulation experiments improves information gain of surface–atmosphere field measurements
UAS Chromatograph for Atmospheric Trace Species (UCATS) – a versatile instrument for trace gas measurements on airborne platforms
Modification of a conventional photolytic converter for improving aircraft measurements of NO2 via chemiluminescence
Bromine speciation in volcanic plumes: new in situ derivatization LC-MS method for the determination of gaseous hydrogen bromide by gas diffusion denuder sampling
Application of a mobile laboratory using a selected-ion flow-tube mass spectrometer (SIFT-MS) for characterisation of volatile organic compounds and atmospheric trace gases
Development of a laser-photofragmentation laser-induced fluorescence instrument for the detection of nitrous acid and hydroxyl radicals in the atmosphere
Calibration and assessment of electrochemical low-cost sensors in remote alpine harsh environments
Intercomparison of IBBCEAS, NitroMAC and FTIR analyses for HONO, NO2 and CH2O measurements during the reaction of NO2 with H2O vapour in the simulation chamber CESAM
Impact of ozone and inlet design on the quantification of isoprene-derived organic nitrates by thermal dissociation cavity ring-down spectroscopy (TD-CRDS)
The Berkeley Environmental Air-quality and CO2 Network: field calibrations of sensor temperature dependence and assessment of network scale CO2 accuracy
Iodide CIMS and m∕z 62: the detection of HNO3 as NO3− in the presence of PAN, peroxyacetic acid and ozone
Airborne Mid-Infrared Cavity enhanced Absorption spectrometer (AMICA)
Ethane measurement by Picarro CRDS G2201-i in laboratory and field conditions: potential and limitations
Andrew W. Seidl, Harald Sodemann, and Hans Christian Steen-Larsen
Atmos. Meas. Tech., 16, 769–790, https://doi.org/10.5194/amt-16-769-2023, https://doi.org/10.5194/amt-16-769-2023, 2023
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It is challenging to make field measurements of stable water isotopes in the Arctic. To this end, we present a modular stable-water-isotope analyzer profiling system. The system operated for a 2-week field campaign on Svalbard during the Arctic winter. We evaluate the system’s performance and analyze any potential impact that the field conditions might have had on the isotopic measurements and the system's ability to resolve isotope gradients in the lowermost layer of the atmosphere.
Daan Swart, Jun Zhang, Shelley van der Graaf, Susanna Rutledge-Jonker, Arjan Hensen, Stijn Berkhout, Pascal Wintjen, René van der Hoff, Marty Haaima, Arnoud Frumau, Pim van den Bulk, Ruben Schulte, Margreet van Zanten, and Thomas van Goethem
Atmos. Meas. Tech., 16, 529–546, https://doi.org/10.5194/amt-16-529-2023, https://doi.org/10.5194/amt-16-529-2023, 2023
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During a 5-week comparison campaign, we tested two set-ups to measure half hourly ammonia fluxes. The eddy covariance and flux gradient systems showed very similar results when the upwind terrain was both homogeneous and free of obstacles. We discuss the technical performance and practical limitations of both systems. Measurements from these instruments can facilitate the study of processes behind ammonia deposition, an important contributor to eutrophication and acidificationin natural areas.
Suding Yang, Xin Li, Limin Zeng, Xuena Yu, Ying Liu, Sihua Lu, Xiaofeng Huang, Dongmei Zhang, Haibin Xu, Shuchen Lin, Hefan Liu, Miao Feng, Danlin Song, Qinwen Tan, Jinhui Cui, Lifan Wang, Ying Chen, Wenjie Wang, Haijiong Sun, Mengdi Song, Liuwei Kong, Yi Liu, Linhui Wei, Xianwu Zhu, and Yuanhang Zhang
Atmos. Meas. Tech., 16, 501–512, https://doi.org/10.5194/amt-16-501-2023, https://doi.org/10.5194/amt-16-501-2023, 2023
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Vertical observation of volatile organic compounds (VOCs) is essential to study the spatial distribution and evolution patterns of VOCs in the planetary boundary layer (PBL). This paper describes multi-channel whole-air sampling equipment onboard an unmanned aerial vehicle (UAV) for near-continuous VOC vertical observation. Vertical profiles of VOCs and trace gases during the evolution of the PBL in south-western China have been successfully obtained by deploying the newly developed UAV system.
Tobias Schuldt, Georgios I. Gkatzelis, Christian Wesolek, Franz Rohrer, Benjamin Winter, Thomas A. J. Kuhlbusch, Astrid Kiendler-Scharr, and Ralf Tillmann
Atmos. Meas. Tech., 16, 373–386, https://doi.org/10.5194/amt-16-373-2023, https://doi.org/10.5194/amt-16-373-2023, 2023
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We report in situ measurements of air pollutant concentrations within the planetary boundary layer on board a Zeppelin NT in Germany. We highlight the in-flight evaluation of electrochemical sensors that were installed inside a hatch box located on the bottom of the Zeppelin. Results from this work emphasize the potential of these sensors for other in situ airborne applications, e.g., on board unmanned aerial vehicles (UAVs).
Leigh S. Fleming, Andrew C. Manning, Penelope A. Pickers, Grant L. Forster, and Alex J. Etchells
Atmos. Meas. Tech., 16, 387–401, https://doi.org/10.5194/amt-16-387-2023, https://doi.org/10.5194/amt-16-387-2023, 2023
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Measurements of atmospheric O2 can help constrain the carbon cycle processes and quantify fossil fuel CO2 emissions; however, measurement of atmospheric O2 is very challenging, and existing analysers are complex systems to build and maintain. We have tested a new O2 analyser (Picarro Inc. G2207-i) in the laboratory and at Weybourne Atmospheric Observatory. We have found that the G2207-i does not perform as well as an existing O2 analyser from Sable Systems Inc.
Siegfried Schobesberger, Emma L. D'Ambro, Lejish Vettikkat, Ben H. Lee, Qiaoyun Peng, David M. Bell, John E. Shilling, Manish Shrivastava, Mikhail Pekour, Jerome Fast, and Joel A. Thornton
Atmos. Meas. Tech., 16, 247–271, https://doi.org/10.5194/amt-16-247-2023, https://doi.org/10.5194/amt-16-247-2023, 2023
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We present a new, highly sensitive technique for measuring atmospheric ammonia, an important trace gas that is emitted mainly by agriculture. We deployed the instrument on an aircraft during research flights over rural Oklahoma. Due to its fast response, we could analyze correlations with turbulent winds and calculate ammonia emissions from nearby areas at 1 to 2 km resolution. We observed high spatial variability and point sources that are not resolved in the US National Emissions Inventory.
Birger Bohn and Insa Lohse
Atmos. Meas. Tech., 16, 209–233, https://doi.org/10.5194/amt-16-209-2023, https://doi.org/10.5194/amt-16-209-2023, 2023
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Optical receivers for solar spectral actinic radiation are designed for angle-independent sensitivities within a hemisphere. Remaining imperfections can be compensated for by receiver-specific corrections based on laboratory characterizations and radiative transfer calculations of spectral radiance distributions. The corrections cover a wide range of realistic atmospheric conditions and were applied to ground-based and airborne measurements in a wavelength range 280–660 nm.
Teles C. Furlani, RenXi Ye, Jordan Stewart, Leigh R. Crilley, Peter M. Edwards, Tara F. Kahan, and Cora J. Young
Atmos. Meas. Tech., 16, 181–193, https://doi.org/10.5194/amt-16-181-2023, https://doi.org/10.5194/amt-16-181-2023, 2023
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This study describes a new technique to measure total gaseous chlorine, which is the sum of gas-phase chlorine-containing chemicals. The method converts any chlorine-containing molecule to hydrogen chloride that can be detected in real time using a cavity ring-down spectrometer. The new method was validated through laboratory experiments, as well as by making measurements of ambient outdoor air and indoor air during cleaning with a chlorine-based cleaner.
Anas Emad and Lukas Siebicke
Atmos. Meas. Tech., 16, 29–40, https://doi.org/10.5194/amt-16-29-2023, https://doi.org/10.5194/amt-16-29-2023, 2023
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The true eddy accumulation (TEA) method enables measuring atmospheric exchange with slow-response gas analyzers. TEA is formulated assuming ideal conditions with a zero mean vertical wind velocity during the averaging interval. This core assumption is rarely valid under field conditions. Here, we extend the TEA equation to accommodate nonideal conditions. The new equation allows constraining the systematic error term in the measured fluxes and the possibility to minimize or remove it.
Anas Emad and Lukas Siebicke
Atmos. Meas. Tech., 16, 41–55, https://doi.org/10.5194/amt-16-41-2023, https://doi.org/10.5194/amt-16-41-2023, 2023
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A new micrometeorological method to measure atmospheric exchange is proposed, and a prototype sampler is evaluated. The new method, called short-time eddy accumulation, is a variant of the eddy accumulation method, which is suited for use with slow gas analyzers. The new method enables adaptive time-varying accumulation intervals, which brings many advantages to flux measurements such as an improved dynamic range and the ability to run eddy accumulation in a continuous flow-through mode.
Lu Xu, Matthew M. Coggon, Chelsea E. Stockwell, Jessica B. Gilman, Michael A. Robinson, Martin Breitenlechner, Aaron Lamplugh, John D. Crounse, Paul O. Wennberg, J. Andrew Neuman, Gordon A. Novak, Patrick R. Veres, Steven S. Brown, and Carsten Warneke
Atmos. Meas. Tech., 15, 7353–7373, https://doi.org/10.5194/amt-15-7353-2022, https://doi.org/10.5194/amt-15-7353-2022, 2022
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We describe the development and operation of a chemical ionization mass spectrometer using an ammonium–water cluster (NH4+·H2O) as a reagent ion. NH4+·H2O is a highly versatile reagent ion for measurements of a wide range of oxygenated organic compounds. The major product ion is the cluster with NH4+ produced via ligand-switching reactions. The instrumental sensitivities of analytes depend on the binding energy of the analyte–NH4+ cluster; sensitivities can be estimated using voltage scanning.
Xiaorui Chen, Haichao Wang, Tianyu Zhai, Chunmeng Li, and Keding Lu
Atmos. Meas. Tech., 15, 7019–7037, https://doi.org/10.5194/amt-15-7019-2022, https://doi.org/10.5194/amt-15-7019-2022, 2022
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N2O5 is an important reservoir of atmospheric nitrogen, on whose interface reaction ambient particles can largely influence the fate of nitrogen oxides and air quality. In this study, we develop an approach to enable the reactions of N2O5 on ambient particles directly in a tube reactor, deriving the reaction rates with high accuracy by means of a chemistry model. Its successful application helps complement the data scarcity and to fill the knowledge gap between laboratory and field results.
Yubin Chen, Bin Yuan, Chaomin Wang, Sihang Wang, Xianjun He, Caihong Wu, Xin Song, Yibo Huangfu, Xiao-Bing Li, Yijia Liao, and Min Shao
Atmos. Meas. Tech., 15, 6935–6947, https://doi.org/10.5194/amt-15-6935-2022, https://doi.org/10.5194/amt-15-6935-2022, 2022
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In this study, we demonstrate that selective online measurements of cycloalkanes can be achieved using proton transfer reaction time-of-flight mass spectrometry with NO+ chemical ionization (NO+ PTR-ToF-MS), with fast response and low detection limits. Applications of this method in both urban air and emission sources will be shown.
Marsailidh M. Twigg, Augustinus J. C. Berkhout, Nicholas Cowan, Sabine Crunaire, Enrico Dammers, Volker Ebert, Vincent Gaudion, Marty Haaima, Christoph Häni, Lewis John, Matthew R. Jones, Bjorn Kamps, John Kentisbeer, Thomas Kupper, Sarah R. Leeson, Daiana Leuenberger, Nils O. B. Lüttschwager, Ulla Makkonen, Nicholas A. Martin, David Missler, Duncan Mounsor, Albrecht Neftel, Chad Nelson, Eiko Nemitz, Rutger Oudwater, Celine Pascale, Jean-Eudes Petit, Andrea Pogany, Nathalie Redon, Jörg Sintermann, Amy Stephens, Mark A. Sutton, Yuk S. Tang, Rens Zijlmans, Christine F. Braban, and Bernhard Niederhauser
Atmos. Meas. Tech., 15, 6755–6787, https://doi.org/10.5194/amt-15-6755-2022, https://doi.org/10.5194/amt-15-6755-2022, 2022
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Ammonia (NH3) gas in the atmosphere impacts the environment, human health, and, indirectly, climate. Historic NH3 monitoring was labour intensive, and the instruments were complicated. Over the last decade, there has been a rapid technology development, including “plug-and-play” instruments. This study is an extensive field comparison of the currently available technologies and provides evidence that for routine monitoring, standard operating protocols are required for datasets to be comparable.
Caroline C. Womack, Steven S. Brown, Steven J. Ciciora, Ru-Shan Gao, Richard J. McLaughlin, Michael A. Robinson, Yinon Rudich, and Rebecca A. Washenfelder
Atmos. Meas. Tech., 15, 6643–6652, https://doi.org/10.5194/amt-15-6643-2022, https://doi.org/10.5194/amt-15-6643-2022, 2022
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We present a new miniature instrument to measure nitrogen dioxide (NO2) using cavity-enhanced spectroscopy. NO2 contributes to the formation of pollutants such as ozone and particulate matter, and its concentration can vary widely near sources. We developed this lightweight (3.05 kg) low-power (<35 W) instrument to measure NO2 on uncrewed aircraft vehicles (UAVs) and demonstrate that it has the accuracy and precision needed for atmospheric field measurements.
John W. Halfacre, Jordan Stewart, Scott C. Herndon, Joseph R. Roscioli, Christoph Dyroff, Tara I. Yacovitch, Michael Flynn, Stephen J. Andrews, Steven S. Brown, Patrick R. Veres, and Pete M. Edwards
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2022-309, https://doi.org/10.5194/amt-2022-309, 2022
Revised manuscript accepted for AMT
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This study details a new sampling method for the optical detection of hydrogen chloride (HCl). HCl is an important atmospheric reservoir for chlorine atoms, which can affect nitrogen oxide cycling and the lifetimes of volatile organic compounds and ozone. However, HCl has a high affinity for interacting with surfaces, thereby preventing fast, quantitative measurements. The sampling technique in this study minimizes these surface interactions and provides a high-quality measurement of HCl.
Alexander Håland, Tomáš Mikoviny, Elisabeth Emilie Syse, and Armin Wisthaler
Atmos. Meas. Tech., 15, 6297–6307, https://doi.org/10.5194/amt-15-6297-2022, https://doi.org/10.5194/amt-15-6297-2022, 2022
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PTR-MS is widely used in atmospheric sciences for the detection of non-methane organic trace gases. The two most widely used types of PTR-MS instruments differ in their ion source and drift tube design. We herein present a new prototype PTR-MS instrument that hybridizes these designs and combines a conventional hollow cathode glow discharge ion source with a focusing ion–molecule reactor. We also show how this new instrument performs in detecting atmospheric amines.
Henning Finkenzeller, Denis Pöhler, Martin Horbanski, Johannes Lampel, and Ulrich Platt
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2022-274, https://doi.org/10.5194/amt-2022-274, 2022
Revised manuscript accepted for AMT
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Optical resonators enhance the light path in compact instruments, thereby improving the sensitivity. Determining the established path length in the instrument is a prerequisite for the accurate determination of trace gas concentrations but can be a significant complication in the use of such resonators. Here we show two calibration techniques which are relatively simple and free of consumables, but still provide accurate calibrations. This facilitates the use of optical resonators.
Gustavo Britto Hupsel de Azevedo, Bill Doyle, Christopher A. Fiebrich, and David Schvartzman
Atmos. Meas. Tech., 15, 5599–5618, https://doi.org/10.5194/amt-15-5599-2022, https://doi.org/10.5194/amt-15-5599-2022, 2022
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Strong changes in pressure, temperature, and humidity occur when small scientific aircraft ascend through the atmosphere to measure carbon dioxide. These strong changes can produce errors in the carbon dioxide measurements. To avoid these errors, we present a low-cost and simple correction method. This low-complexity method allows more researchers to study atmospheric carbon dioxide, reducing entry barriers in this field.
Ilann Bourgeois, Jeff Peischl, J. Andrew Neuman, Steven S. Brown, Hannah M. Allen, Pedro Campuzano-Jost, Matthew M. Coggon, Joshua P. DiGangi, Glenn S. Diskin, Jessica B. Gilman, Georgios I. Gkatzelis, Hongyu Guo, Hannah A. Halliday, Thomas F. Hanisco, Christopher D. Holmes, L. Gregory Huey, Jose L. Jimenez, Aaron D. Lamplugh, Young Ro Lee, Jakob Lindaas, Richard H. Moore, Benjamin A. Nault, John B. Nowak, Demetrios Pagonis, Pamela S. Rickly, Michael A. Robinson, Andrew W. Rollins, Vanessa Selimovic, Jason M. St. Clair, David Tanner, Krystal T. Vasquez, Patrick R. Veres, Carsten Warneke, Paul O. Wennberg, Rebecca A. Washenfelder, Elizabeth B. Wiggins, Caroline C. Womack, Lu Xu, Kyle J. Zarzana, and Thomas B. Ryerson
Atmos. Meas. Tech., 15, 4901–4930, https://doi.org/10.5194/amt-15-4901-2022, https://doi.org/10.5194/amt-15-4901-2022, 2022
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Understanding fire emission impacts on the atmosphere is key to effective air quality management and requires accurate measurements. We present a comparison of airborne measurements of key atmospheric species in ambient air and in fire smoke. We show that most instruments performed within instrument uncertainties. In some cases, further work is needed to fully characterize instrument performance. Comparing independent measurements using different techniques is important to assess their accuracy.
Benjamin Birner, Eric Morgan, and Ralph F. Keeling
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2022-242, https://doi.org/10.5194/amt-2022-242, 2022
Revised manuscript accepted for AMT
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Atmospheric variations of helium (He) and CO2 are strongly linked due to the co-released of both gases from natural gas burning. This implies atmospheric He measurements may be a potentially powerful tool for verifying reported anthropogenic natural gas usage. Here we present the development and initial results of a novel measurement system of atmospheric He that paves the way for establishing a global monitoring network in the future.
Tatsumi Nakano and Takashi Morofuji
EGUsphere, https://doi.org/10.5194/egusphere-2022-565, https://doi.org/10.5194/egusphere-2022-565, 2022
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We have developed a system that can automatically measure the pump efficiency of the ECC type ozonesonde. Operational measurement for ten years by this system revealed that the efficiency fluctuates in each and slightly increases over time. Those can affect the estimation of total ozone amount by up to 4 %. This result indicates that it is necessary to understand the tendency of the pump correction factor of each ozonesonde in order to detect the actual atmospheric change with high accuracy.
Woohui Nam, Changmin Cho, Begie Perdigones, Tae Siek Rhee, and Kyung-Eun Min
Atmos. Meas. Tech., 15, 4473–4487, https://doi.org/10.5194/amt-15-4473-2022, https://doi.org/10.5194/amt-15-4473-2022, 2022
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We describe our vibration-resistant instrument for measuring ambient NO3, NO2, and H2O based on cavity-enhanced absorption spectroscopy. By simultaneous retrieval of H2O with the other species using a measured H2O absorption spectrum, direct quantifications among all species are possible without any pre-treatment for H2O. Our instrument achieves the effective light path to ~101.5 km, which allows the sensitive measurements of NO3 and NO2 as 1.41 pptv and 6.92 ppbv (1σ) in 1 s.
Yunsong Liu, Jean-Daniel Paris, Mihalis Vrekoussis, Panayiota Antoniou, Christos Constantinides, Maximilien Desservettaz, Christos Keleshis, Olivier Laurent, Andreas Leonidou, Carole Philippon, Panagiotis Vouterakos, Pierre-Yves Quéhé, Philippe Bousquet, and Jean Sciare
Atmos. Meas. Tech., 15, 4431–4442, https://doi.org/10.5194/amt-15-4431-2022, https://doi.org/10.5194/amt-15-4431-2022, 2022
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This paper details laboratory-based and field developments of a cost-effective and compacted UAV CO2 sensor system to address the challenge of measuring CO2 with sufficient precision and acquisition frequency. We assess its performance extensively through laboratory and field tests and provide a case study in an urban area (Nicosia, Cyprus). We therefore expect that this portable system will be widely used for measuring CO2 emission and distribution in natural or urban environments.
Subin Yoon, Alexander Kotsakis, Sergio L. Alvarez, Mark G. Spychala, Elizabeth Klovenski, Paul Walter, Gary Morris, Ernesto Corrales, Alfredo Alan, Jorge A. Diaz, and James H. Flynn
Atmos. Meas. Tech., 15, 4373–4384, https://doi.org/10.5194/amt-15-4373-2022, https://doi.org/10.5194/amt-15-4373-2022, 2022
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SO2 is adverse to human health and the environment. A single SO2 sonde was developed to provide direct SO2 measurement with a greater vertical extent, a lower limit of detection, and less uncertainty relative to the previous dual-sonde method. The single sonde was tested in the field near volcanoes and anthropogenic sources where the sonde measured SO2 ranging from 0.5 to 940 ppb. This lighter-weight payload can be a great candidate to attach to small drones and unmanned aerial vehicles.
Michael A. Robinson, J. Andrew Neuman, L. Gregory Huey, James M. Roberts, Steven S. Brown, and Patrick R. Veres
Atmos. Meas. Tech., 15, 4295–4305, https://doi.org/10.5194/amt-15-4295-2022, https://doi.org/10.5194/amt-15-4295-2022, 2022
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Iodide chemical ionization mass spectrometry (CIMS) is commonly used in atmospheric chemistry laboratory studies and field campaigns. Deployment of the NOAA iodide CIMS instrument in the summer of 2021 indicated a significant and overlooked temperature dependence of the instrument sensitivity. This work explores which analytes are influenced by this phenomena. Additionally, we recommend controls to reduce this effect for future field deployments.
Roland Vernooij, Patrik Winiger, Martin Wooster, Tercia Strydom, Laurent Poulain, Ulrike Dusek, Mark Grosvenor, Gareth J. Roberts, Nick Schutgens, and Guido R. van der Werf
Atmos. Meas. Tech., 15, 4271–4294, https://doi.org/10.5194/amt-15-4271-2022, https://doi.org/10.5194/amt-15-4271-2022, 2022
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Landscape fires are a substantial emitter of greenhouse gases and aerosols. Previous studies have indicated savanna emission factors to be highly variable. Improving fire emission estimates, and understanding future climate- and human-induced changes in fire regimes, requires in situ measurements. We present a drone-based method that enables the collection of a large amount of high-quality emission factor measurements that do not have the biases of aircraft or surface measurements.
Ralf Tillmann, Georgios I. Gkatzelis, Franz Rohrer, Benjamin Winter, Christian Wesolek, Tobias Schuldt, Anne C. Lange, Philipp Franke, Elmar Friese, Michael Decker, Robert Wegener, Morten Hundt, Oleg Aseev, and Astrid Kiendler-Scharr
Atmos. Meas. Tech., 15, 3827–3842, https://doi.org/10.5194/amt-15-3827-2022, https://doi.org/10.5194/amt-15-3827-2022, 2022
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We report in situ measurements of air pollutant concentrations within the planetary boundary layer on board a Zeppelin in Germany. The low costs of commercial flights provide an affordable and efficient method to improve our understanding of changes in emissions in space and time. The experimental setup expands the capabilities of this platform and provides insights into primary and secondary pollution observations and planetary boundary layer dynamics which determine air quality significantly.
Mei Bai, Zoe Loh, David W. T. Griffith, Debra Turner, Richard Eckard, Robert Edis, Owen T. Denmead, Glenn W. Bryant, Clare Paton-Walsh, Matthew Tonini, Sean M. McGinn, and Deli Chen
Atmos. Meas. Tech., 15, 3593–3610, https://doi.org/10.5194/amt-15-3593-2022, https://doi.org/10.5194/amt-15-3593-2022, 2022
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The open-path laser (OPL) and open-path Fourier transform infrared (OP-FTIR) are used in agricultural research, but their error in emissions research has not been the focus of studies. We conducted trace gas release trials and herd and paddock emission studies to compare their applicability and performance. The OP-FTIR has better stability in stable conditions than OPL. The CH4 OPL accurately detects the low background level of CH4, but the NH3 OPL only detects background values >10 ppbv.
Roger Curcoll, Josep-Anton Morguí, Armand Kamnang, Lídia Cañas, Arturo Vargas, and Claudia Grossi
Atmos. Meas. Tech., 15, 2807–2818, https://doi.org/10.5194/amt-15-2807-2022, https://doi.org/10.5194/amt-15-2807-2022, 2022
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Low-cost air enquirer kits, including CO2 and environmental parameter sensors, have been designed, built, and tested in a new steady-state through-flow chamber for simultaneous measurements of CO2 fluxes in soil and CO2 concentrations in air. A CO2 calibration and multiparametric fitting reduced the total uncertainty of CO2 concentration by 90 %. This system allows continuous measurement of CO2 fluxes and CO2 ambient air, with low cost (EUR 1200), low energy demand (<5 W), and low maintenance.
Lisa von der Heyden, Walter Wißdorf, Ralf Kurtenbach, and Jörg Kleffmann
Atmos. Meas. Tech., 15, 1983–2000, https://doi.org/10.5194/amt-15-1983-2022, https://doi.org/10.5194/amt-15-1983-2022, 2022
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A relaxed eddy accumulation (REA) system based on the LOPAP technique for the quantification of vertical fluxes of nitrous acid (HONO) was developed and tested in a field campaign. Typical diurnal variations of the HONO fluxes were observed with low, partly negative fluxes during night-time and higher positive fluxes around noon. The highest correlation of the HONO flux was observed with the product of the NO2 photolysis frequency and the NO2 concentration.
Pieter Tans
Atmos. Meas. Tech., 15, 1903–1916, https://doi.org/10.5194/amt-15-1903-2022, https://doi.org/10.5194/amt-15-1903-2022, 2022
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The AirCore collects a continuous air sample in a long tube that can be read later when the captured air is slowly pushed through an analyzer. Much of the variation of gas composition encountered during collection is preserved, like having up to ~ 100 separate air samples. This is illustrated through examples of actual flights, and the analysis algorithm is described. The AirCore provides access to air as high as the mid stratosphere, enabling validation for satellite air composition soundings.
Peter Sperlich, Gordon W. Brailsford, Rowena C. Moss, John McGregor, Ross J. Martin, Sylvia Nichol, Sara Mikaloff-Fletcher, Beata Bukosa, Magda Mandic, C. Ian Schipper, Paul Krummel, and Alan D. Griffiths
Atmos. Meas. Tech., 15, 1631–1656, https://doi.org/10.5194/amt-15-1631-2022, https://doi.org/10.5194/amt-15-1631-2022, 2022
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We tested an in situ analyser for carbon and oxygen isotopes in atmospheric CO2 at Baring Head, New Zealand’s observatory for Southern Ocean baseline air. The analyser was able to resolve regional signals of the terrestrial carbon cycle, although the analysis of small events was limited by analytical uncertainty. Further improvement of the instrument performance would be desirable for the robust analysis of distant signals and to resolve the small variability in Southern Ocean baseline air.
Martin Breitenlechner, Gordon A. Novak, J. Andrew Neuman, Andrew W. Rollins, and Patrick R. Veres
Atmos. Meas. Tech., 15, 1159–1169, https://doi.org/10.5194/amt-15-1159-2022, https://doi.org/10.5194/amt-15-1159-2022, 2022
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We coupled a new ion source to a commercially available state-of-the-art trace gas analyzer. The instrument is particularly well suited for conducting high-altitude observations, addressing the challenges of low ambient pressures and a complex sample matrix. The new instrument and ion source provides significant advantages to more traditional modes of operation, without sacrificing the sensitivity and flexibility of this technique.
Jianqiang Zeng, Yanli Zhang, Huina Zhang, Wei Song, Zhenfeng Wu, and Xinming Wang
Atmos. Meas. Tech., 15, 79–93, https://doi.org/10.5194/amt-15-79-2022, https://doi.org/10.5194/amt-15-79-2022, 2022
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The emission of biogenic volatile organic compounds (BVOCs) from plant leaves is an essential part of biosphere–atmosphere interactions. Here we demonstrate how a dynamic chamber for measuring branch-scale BVOC emissions could be characterized both in the lab for adsorptive losses and in the field for ambient–enclosure environmental differences. The results also imply emission factors for terpenes might be underestimated if measured using dynamic chambers without certified transfer efficiencies.
Lukas Fischer, Martin Breitenlechner, Eva Canaval, Wiebke Scholz, Marcus Striednig, Martin Graus, Thomas G. Karl, Tuukka Petäjä, Markku Kulmala, and Armin Hansel
Atmos. Meas. Tech., 14, 8019–8039, https://doi.org/10.5194/amt-14-8019-2021, https://doi.org/10.5194/amt-14-8019-2021, 2021
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Ecosystems emit biogenic volatile organic compounds (BVOCs), which are then oxidized in the atmosphere, contributing to ozone and secondary aerosol formation. While flux measurements of BVOCs are state of the art, flux measurements of the less volatile oxidation products are difficult to achieve due to inlet losses. Here we present first flux measurements, utilizing a novel PTR3 instrument in combination with a specially designed wall-less inlet we put on top of the Hyytiälä tower in Finland.
Kevin S. Rozmiarek, Bruce H. Vaughn, Tyler R. Jones, Valerie Morris, William B. Skorski, Abigail G. Hughes, Jack Elston, Sonja Wahl, Anne-Katrine Faber, and Hans Christian Steen-Larsen
Atmos. Meas. Tech., 14, 7045–7067, https://doi.org/10.5194/amt-14-7045-2021, https://doi.org/10.5194/amt-14-7045-2021, 2021
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We have designed an unmanned aerial vehicle (UAV) sampling platform for operation in extreme polar environments that is capable of sampling atmospheric water vapor for subsequent measurement of water isotopes. During flight, we measure location, temperature, humidity, and pressure to determine the height of the planetary boundary layer (PBL) using algorithms, allowing for strategic decision-making by the pilot to collect samples in glass flasks contained in the nose cone of the UAV.
Stefan Metzger, David Durden, Sreenath Paleri, Matthias Sühring, Brian J. Butterworth, Christopher Florian, Matthias Mauder, David M. Plummer, Luise Wanner, Ke Xu, and Ankur R. Desai
Atmos. Meas. Tech., 14, 6929–6954, https://doi.org/10.5194/amt-14-6929-2021, https://doi.org/10.5194/amt-14-6929-2021, 2021
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The key points are the following. (i) Integrative observing system design can multiply the information gain of surface–atmosphere field measurements. (ii) Catalyzing numerical simulations and first-principles machine learning open up observing system simulation experiments to novel applications. (iii) Use cases include natural climate solutions, emission inventory validation, urban air quality, and industry leak detection.
Eric J. Hintsa, Fred L. Moore, Dale F. Hurst, Geoff S. Dutton, Bradley D. Hall, J. David Nance, Ben R. Miller, Stephen A. Montzka, Laura P. Wolton, Audra McClure-Begley, James W. Elkins, Emrys G. Hall, Allen F. Jordan, Andrew W. Rollins, Troy D. Thornberry, Laurel A. Watts, Chelsea R. Thompson, Jeff Peischl, Ilann Bourgeois, Thomas B. Ryerson, Bruce C. Daube, Yenny Gonzalez Ramos, Roisin Commane, Gregory W. Santoni, Jasna V. Pittman, Steven C. Wofsy, Eric Kort, Glenn S. Diskin, and T. Paul Bui
Atmos. Meas. Tech., 14, 6795–6819, https://doi.org/10.5194/amt-14-6795-2021, https://doi.org/10.5194/amt-14-6795-2021, 2021
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We built UCATS to study atmospheric chemistry and transport. It has measured trace gases including CFCs, N2O, SF6, CH4, CO, and H2 with gas chromatography, as well as ozone and water vapor. UCATS has been part of missions to study the tropical tropopause; transport of air into the stratosphere; greenhouse gases, transport, and chemistry in the troposphere; and ozone chemistry, on both piloted and unmanned aircraft. Its design, capabilities, and some results are shown and described here.
Clara M. Nussbaumer, Uwe Parchatka, Ivan Tadic, Birger Bohn, Daniel Marno, Monica Martinez, Roland Rohloff, Hartwig Harder, Flora Kluge, Klaus Pfeilsticker, Florian Obersteiner, Martin Zöger, Raphael Doerich, John N. Crowley, Jos Lelieveld, and Horst Fischer
Atmos. Meas. Tech., 14, 6759–6776, https://doi.org/10.5194/amt-14-6759-2021, https://doi.org/10.5194/amt-14-6759-2021, 2021
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NO2 plays a central role in atmospheric photochemical processes and requires accurate measurements. This research presents NO2 data obtained via chemiluminescence using a photolytic converter from airborne studies around Cabo Verde and laboratory investigations. We show the limits and error-proneness of a conventional blue light converter in aircraft measurements affected by humidity and NO levels and suggest the use of an alternative quartz converter for more reliable results.
Alexandra Gutmann, Nicole Bobrowski, Marcello Liotta, and Thorsten Hoffmann
Atmos. Meas. Tech., 14, 6395–6406, https://doi.org/10.5194/amt-14-6395-2021, https://doi.org/10.5194/amt-14-6395-2021, 2021
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Motivated by a special interest in bromine chemistry in volcanic plumes, the study presented here describes a new method for the quantitative collection of gaseous hydrogen bromide in gas diffusion denuders. The hydrogen bromide reacted during sampling with appropriate epoxides applied to the denuder walls. The denuder sampling assembly was successfully deployed in the volcanic plume of Masaya volcano, Nicaragua.
Rebecca L. Wagner, Naomi J. Farren, Jack Davison, Stuart Young, James R. Hopkins, Alastair C. Lewis, David C. Carslaw, and Marvin D. Shaw
Atmos. Meas. Tech., 14, 6083–6100, https://doi.org/10.5194/amt-14-6083-2021, https://doi.org/10.5194/amt-14-6083-2021, 2021
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We describe the use of a selected-ion flow-tube mass spectrometer (SIFT-MS) in a mobile laboratory to provide on-road, high spatial and temporal measurements of CO2, CH4, multiple volatile organic compounds (VOCs) and other trace gases. Results are presented that highlight the potential of this platform for developing characterisation methods of different emissions sources in complex urban areas.
Brandon Bottorff, Emily Reidy, Levi Mielke, Sebastien Dusanter, and Philip S. Stevens
Atmos. Meas. Tech., 14, 6039–6056, https://doi.org/10.5194/amt-14-6039-2021, https://doi.org/10.5194/amt-14-6039-2021, 2021
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Nitrous acid (HONO) is an important source of hydroxyl (OH) radicals, the primary oxidant in the atmosphere. Accurate measurements of HONO are thus important to understand the oxidative capacity of the atmosphere. A new instrument capable of measuring atmospheric nitrous acid (HONO) with high sensitivity is presented, utilizing laser photofragmentation of ambient HONO and subsequent detection of the OH radical fragment.
Federico Dallo, Daniele Zannoni, Jacopo Gabrieli, Paolo Cristofanelli, Francescopiero Calzolari, Fabrizio de Blasi, Andrea Spolaor, Dario Battistel, Rachele Lodi, Warren Raymond Lee Cairns, Ann Mari Fjæraa, Paolo Bonasoni, and Carlo Barbante
Atmos. Meas. Tech., 14, 6005–6021, https://doi.org/10.5194/amt-14-6005-2021, https://doi.org/10.5194/amt-14-6005-2021, 2021
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Our work showed how the adoption of low-cost technology could be useful in environmental research and monitoring. We focused our work on tropospheric ozone, but we also showed how to make a general purpose low-cost sensing system which may be adapted and optimised to be used in many other case studies. Given the importance of providing quality data, we put a lot of effort in the sensor's calibration, and we believe that our results show how to exploit the potential of the low-cost technology.
Hongming Yi, Mathieu Cazaunau, Aline Gratien, Vincent Michoud, Edouard Pangui, Jean-Francois Doussin, and Weidong Chen
Atmos. Meas. Tech., 14, 5701–5715, https://doi.org/10.5194/amt-14-5701-2021, https://doi.org/10.5194/amt-14-5701-2021, 2021
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HONO and NO2 play a crucial role in the atmospheric oxidation capacity that affects the regional air quality and global climate. Accurate measurements of HONO are challenging due to the drawback of existing detection methods. Calibration-free high-sensitivity direct, simultaneous measurements of NO2, HONO and CH2O with UV-IBBCEAS provide accurate and fast quantitative analysis of their concentration variation within their lifetime by intercomparison with NOx, FTIR and NitroMAC sensors.
Patrick Dewald, Raphael Dörich, Jan Schuladen, Jos Lelieveld, and John N. Crowley
Atmos. Meas. Tech., 14, 5501–5519, https://doi.org/10.5194/amt-14-5501-2021, https://doi.org/10.5194/amt-14-5501-2021, 2021
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Organic nitrates generated from the reaction between isoprene and the nitrate radical (ISOP-NITs) were detected via their thermal dissociation in heated quartz inlets to nitrogen dioxide monitored by cavity ring-down spectroscopy. The temperature-dependent dissociation profiles of ISOP-NITs in the presence of ozone (O3) are broad in contrast to narrow profiles of common reference compounds. We demonstrate that this broadening is caused by O3-assisted reactions of ISOP-NITs on quartz surfaces.
Erin R. Delaria, Jinsol Kim, Helen L. Fitzmaurice, Catherine Newman, Paul J. Wooldridge, Kevin Worthington, and Ronald C. Cohen
Atmos. Meas. Tech., 14, 5487–5500, https://doi.org/10.5194/amt-14-5487-2021, https://doi.org/10.5194/amt-14-5487-2021, 2021
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The use of a dense network of low-cost CO2 sensors is an attractive option for measuring CO2 emissions in cities. However, these low-cost sensors are also subject to uncertainties. Here, we describe a novel method of field calibration for correcting temperature-related errors in the CO2 sensors deployed in the BEACO2N network. We show that with this temperature correction, we can achieve a sufficiently low network error to allow for the evaluation of CO2 emissions at a neighborhood scale.
Raphael Dörich, Philipp Eger, Jos Lelieveld, and John N. Crowley
Atmos. Meas. Tech., 14, 5319–5332, https://doi.org/10.5194/amt-14-5319-2021, https://doi.org/10.5194/amt-14-5319-2021, 2021
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We demonstrate in laboratory experiments that the formation of IOx anions (formed in reactions of I− with O3) or acetate anions (formed e.g. by the reaction of I− with peracetic acid) results in unexpected sensitivity of an iodide chemical ionisation mass spectrometer (I-CIMS) to HNO3 at a mass-to-charge ratio of 62. This helps explain observations of apparent high daytime levels of N2O5. Airborne measurements using I-CIMS confirm these conclusions.
Corinna Kloss, Vicheith Tan, J. Brian Leen, Garrett L. Madsen, Aaron Gardner, Xu Du, Thomas Kulessa, Johannes Schillings, Herbert Schneider, Stefanie Schrade, Chenxi Qiu, and Marc von Hobe
Atmos. Meas. Tech., 14, 5271–5297, https://doi.org/10.5194/amt-14-5271-2021, https://doi.org/10.5194/amt-14-5271-2021, 2021
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We describe the innovative analyzer
AMICAfor airborne trace gas measurements by infrared spectroscopy. Its design makes it robust and allows for sensitive measurements. AMICA has been used on two different aircraft for measuring gases including carbonyl sulfide, carbon monoxide and ozone. With fairly simple adaptions, AMICA can measure many stable trace gases that absorb light in the infrared.
Sara M. Defratyka, Jean-Daniel Paris, Camille Yver-Kwok, Daniel Loeb, James France, Jon Helmore, Nigel Yarrow, Valérie Gros, and Philippe Bousquet
Atmos. Meas. Tech., 14, 5049–5069, https://doi.org/10.5194/amt-14-5049-2021, https://doi.org/10.5194/amt-14-5049-2021, 2021
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We consider the possibility of using the CRDS Picarro G2201-i instrument, originally designed for isotopic CH4 and CO2, for measurements of ethane : methane in near-source conditions. The work involved laboratory tests, a controlled release experiment and mobile measurements. We show the potential of determining ethane : methane with 50 ppb ethane uncertainty. The instrument can correctly estimate the ratio in CH4 enhancements of 1 ppm and more, as can be found at strongly emitting sites.
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