Articles | Volume 6, issue 7 
            
                
                    
            
            
            https://doi.org/10.5194/amt-6-1611-2013
                    © 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-6-1611-2013
                    © Author(s) 2013. This work is distributed under 
the Creative Commons Attribution 3.0 License.
                the Creative Commons Attribution 3.0 License.
Towards a stable and absolute atmospheric carbon dioxide instrument using spectroscopic null method
B. Xiang
                                            School of Engineering and Applied Science and Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138, USA
                                        
                                    D. D. Nelson
                                            Aerodyne Research, Inc., 45 Manning Road, Billerica, MA 01821-3976, USA
                                        
                                    J. B. McManus
                                            Aerodyne Research, Inc., 45 Manning Road, Billerica, MA 01821-3976, USA
                                        
                                    M. S. Zahniser
                                            Aerodyne Research, Inc., 45 Manning Road, Billerica, MA 01821-3976, USA
                                        
                                    S. C. Wofsy
                                            School of Engineering and Applied Science and Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138, USA
                                        
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B. Xiang, D. D. Nelson, J. B. McManus, M. S. Zahniser, R. A. Wehr, and S. C. Wofsy
                                    Atmos. Meas. Tech., 7, 4445–4453, https://doi.org/10.5194/amt-7-4445-2014, https://doi.org/10.5194/amt-7-4445-2014, 2014
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                                                We designed and built a spectrometer, ABsolute Carbon dioxide (ABC), to measure atmospheric concentration of carbon dioxide. This instrument was tested in a forest environment for almost a year. Based on results from this long-term field deployment, we proved that ABC has the capability of performing high-accuracy, unattended, continuous field measurements with minimal use of reference gas cylinders.
                                            
                                            
                                        G. W. Santoni, B. C. Daube, E. A. Kort, R. Jiménez, S. Park, J. V. Pittman, E. Gottlieb, B. Xiang, M. S. Zahniser, D. D. Nelson, J. B. McManus, J. Peischl, T. B. Ryerson, J. S. Holloway, A. E. Andrews, C. Sweeney, B. Hall, E. J. Hintsa, F. L. Moore, J. W. Elkins, D. F. Hurst, B. B. Stephens, J. Bent, and S. C. Wofsy
                                    Atmos. Meas. Tech., 7, 1509–1526, https://doi.org/10.5194/amt-7-1509-2014, https://doi.org/10.5194/amt-7-1509-2014, 2014
                            Timo Vesala, Kukka-Maaria Kohonen, Linda M. J. Kooijmans, Arnaud P. Praplan, Lenka Foltýnová, Pasi Kolari, Markku Kulmala, Jaana Bäck, David Nelson, Dan Yakir, Mark Zahniser, and Ivan Mammarella
                                    Atmos. Chem. Phys., 22, 2569–2584, https://doi.org/10.5194/acp-22-2569-2022, https://doi.org/10.5194/acp-22-2569-2022, 2022
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                                                Carbonyl sulfide (COS) provides new insights into carbon cycle research. We present an easy-to-use flux parameterization and the longest existing time series of forest–atmosphere COS exchange measurements, which allow us to study both seasonal and interannual variability. We observed only uptake of COS by the forest on an annual basis, with 37 % variability between years. Upscaling the boreal COS uptake using a biosphere model indicates a significant missing COS sink at high latitudes.
                                            
                                            
                                        Pharahilda M. Steur, Hubertus A. Scheeren, Dave D. Nelson, J. Barry McManus, and Harro A. J. Meijer
                                    Atmos. Meas. Tech., 14, 4279–4304, https://doi.org/10.5194/amt-14-4279-2021, https://doi.org/10.5194/amt-14-4279-2021, 2021
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                                                For understanding the sources and sinks of atmospheric CO2, measurement of stable isotopes has proven to be highly valuable. We present a new method using laser absorption spectroscopy to simultaneously conduct measurements of three CO2 isotopes, directly on dry-air samples. This new method reduces sample preparation time significantly, compared to the conventional method in which measurements are conducted on pure CO2, and avoids measurement biases introduced by CO2 extraction.
                                            
                                            
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                                                Leaf stomata influence both photosynthesis and transpiration, coupling the carbon and water cycles, but there is no direct method for estimating stomatal behavior on the ecosystem scale. We use the ecosystem–atmosphere exchange of water, heat, and carbonyl sulfide to estimate canopy-integrated stomatal conductance by two independent methods. We then use that conductance to show that the seasonal dynamics of transpiration and evaporation are different than represented in current biosphere models.
                                            
                                            
                                        Linda M. J. Kooijmans, Nelly A. M. Uitslag, Mark S. Zahniser, David D. Nelson, Stephen A. Montzka, and Huilin Chen
                                    Atmos. Meas. Tech., 9, 5293–5314, https://doi.org/10.5194/amt-9-5293-2016, https://doi.org/10.5194/amt-9-5293-2016, 2016
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                                                The accuracy of carbon models, used for the prediction of global climate change, is limited by the knowledge of the uptake of carbon by plants through photosynthesis. Carbonyl sulfide (COS) has been suggested as a tracer for this process. To be able to further explore and verify the application of this novel tracer we have tested a laser spectrometer for its suitability to obtain accurate and high precision measurements of COS and CO2 with both laboratory experiments and field measurements.
                                            
                                            
                                        Mari Pihlatie, Üllar Rannik, Sami Haapanala, Olli Peltola, Narasinha Shurpali, Pertti J. Martikainen, Saara Lind, Niina Hyvönen, Perttu Virkajärvi, Mark Zahniser, and Ivan Mammarella
                                    Biogeosciences, 13, 5471–5485, https://doi.org/10.5194/bg-13-5471-2016, https://doi.org/10.5194/bg-13-5471-2016, 2016
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                                                The sources and sinks of carbon monoxide (CO) in the biosphere are poorly understood. We report the first continuous data series of CO fluxes measured by eddy covariance method in an agricultural bioenergy crop. The CO fluxes were seasonally and diurnally variable demonstrating the parallel consumption and production processes. Radiation was the main driver of CO emissions, and the eddy covariance method was demonstrated as suitable for linking short-term flux dynamics to environmental drivers.
                                            
                                            
                                        Undine Zöll, Christian Brümmer, Frederik Schrader, Christof Ammann, Andreas Ibrom, Christophe R. Flechard, David D. Nelson, Mark Zahniser, and Werner L. Kutsch
                                    Atmos. Chem. Phys., 16, 11283–11299, https://doi.org/10.5194/acp-16-11283-2016, https://doi.org/10.5194/acp-16-11283-2016, 2016
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                                                Accurate quantification of atmospheric ammonia concentration and exchange fluxes with the land surface has been a major metrological challenge. We demonstrate the applicability of a novel laser device to identify concentration and flux patterns over a peatland ecosystem influenced by nearby agricultural practices. Results help to strengthen air quality monitoring networks, lead to better understanding of ecosystem functionality and improve parameterizations in air chemistry and transport models.
                                            
                                            
                                        Xiyan Xu, William J. Riley, Charles D. Koven, Dave P. Billesbach, Rachel Y.-W. Chang, Róisín Commane, Eugénie S. Euskirchen, Sean Hartery, Yoshinobu Harazono, Hiroki Iwata, Kyle C. McDonald, Charles E. Miller, Walter C. Oechel, Benjamin Poulter, Naama Raz-Yaseef, Colm Sweeney, Margaret Torn, Steven C. Wofsy, Zhen Zhang, and Donatella Zona
                                    Biogeosciences, 13, 5043–5056, https://doi.org/10.5194/bg-13-5043-2016, https://doi.org/10.5194/bg-13-5043-2016, 2016
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                                                Wetlands are the largest global natural methane source. Peat-rich bogs and fens lying between 50°N and 70°N contribute 10–30% to this source. The predictive capability of the seasonal methane cycle can directly affect the estimation of global methane budget. We present multiscale methane seasonal emission by observations and modeling and find that the uncertainties in predicting the seasonal methane emissions are from the wetland extent, cold-season CH4 production and CH4 transport processes.
                                            
                                            
                                        Christian Frankenberg, Susan S. Kulawik, Steven C. Wofsy, Frédéric Chevallier, Bruce Daube, Eric A. Kort, Christopher O'Dell, Edward T. Olsen, and Gregory Osterman
                                    Atmos. Chem. Phys., 16, 7867–7878, https://doi.org/10.5194/acp-16-7867-2016, https://doi.org/10.5194/acp-16-7867-2016, 2016
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                                                We use observations from the HIAPER Pole-to-Pole Observations (HIPPO) flights from January 2009 through September 2011 to validate CO2 measurements from satellites (GOSAT, TES, AIRS) and atmospheric inversion models (CarbonTracker CT2013B, MACC v13r1).
                                            
                                            
                                        J. R. Pitt, M. Le Breton, G. Allen, C. J. Percival, M. W. Gallagher, S. J.-B. Bauguitte, S. J. O'Shea, J. B. A. Muller, M. S. Zahniser, J. Pyle, and P. I. Palmer
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                                        F. Deng, D. B. A. Jones, T. W. Walker, M. Keller, K. W. Bowman, D. K. Henze, R. Nassar, E. A. Kort, S. C. Wofsy, K. A. Walker, A. E. Bourassa, and D. A. Degenstein
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                                                The upper troposphere and lower stratosphere (UTLS) is characterized by strong gradients in the distribution of long-lived tracers, which are sensitive to discrepancies in transport in models. We found that our model overestimates CO2 in the polar UTLS through comparison of modeled CO2 with aircraft observations. We then corrected the modeled CO2 and quantified the impact of the correction on the flux estimates using an atmospheric model together with atmospheric CO2 measured from a satellite.
                                            
                                            
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                                                This paper introduces a new inversion framework for N2O using GEOS-Chem and its adjoint, which we employed in a series of observing system simulation experiments to evaluate the source and sink constraints provided by surface and aircraft-based N2O measurements. We also applied a new approach for estimating a posteriori uncertainty for high-dimensional inversions, and used it to quantify the spatial and temporal resolution of N2O emission constraints achieved with the current observing network.
                                            
                                            
                                        L. Molina, G. Broquet, P. Imbach, F. Chevallier, B. Poulter, D. Bonal, B. Burban, M. Ramonet, L. V. Gatti, S. C. Wofsy, J. W. Munger, E. Dlugokencky, and P. Ciais
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                            C. Dyroff, S. Sanati, E. Christner, A. Zahn, M. Balzer, H. Bouquet, J. B. McManus, Y. González-Ramos, and M. Schneider
                                    Atmos. Meas. Tech., 8, 2037–2049, https://doi.org/10.5194/amt-8-2037-2015, https://doi.org/10.5194/amt-8-2037-2015, 2015
                            J. M. Henderson, J. Eluszkiewicz, M. E. Mountain, T. Nehrkorn, R. Y.-W. Chang, A. Karion, J. B. Miller, C. Sweeney, N. Steiner, S. C. Wofsy, and C. E. Miller
                                    Atmos. Chem. Phys., 15, 4093–4116, https://doi.org/10.5194/acp-15-4093-2015, https://doi.org/10.5194/acp-15-4093-2015, 2015
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                                                This paper describes the atmospheric modeling that underlies the science analysis for the NASA Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE). Summary statistics of the WRF meteorological model performance on a 3.3 km grid indicate good overall agreement with surface and radiosonde observations. The high quality of the WRF meteorological fields inspires confidence in their use to drive the STILT transport model for the purpose of computing surface influence fields (“footprints”).
                                            
                                            
                                        M. J. Alvarado, V. H. Payne, K. E. Cady-Pereira, J. D. Hegarty, S. S. Kulawik, K. J. Wecht, J. R. Worden, J. V. Pittman, and S. C. Wofsy
                                    Atmos. Meas. Tech., 8, 965–985, https://doi.org/10.5194/amt-8-965-2015, https://doi.org/10.5194/amt-8-965-2015, 2015
                            Ü. Rannik, S. Haapanala, N. J. Shurpali, I. Mammarella, S. Lind, N. Hyvönen, O. Peltola, M. Zahniser, P. J. Martikainen, and T. Vesala
                                    Biogeosciences, 12, 415–432, https://doi.org/10.5194/bg-12-415-2015, https://doi.org/10.5194/bg-12-415-2015, 2015
                            M. M. Bela, K. M. Longo, S. R. Freitas, D. S. Moreira, V. Beck, S. C. Wofsy, C. Gerbig, K. Wiedemann, M. O. Andreae, and P. Artaxo
                                    Atmos. Chem. Phys., 15, 757–782, https://doi.org/10.5194/acp-15-757-2015, https://doi.org/10.5194/acp-15-757-2015, 2015
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                                                In the Amazon Basin, gases that lead to the formation of ozone (O3), an air pollutant and greenhouse gas, are emitted from fire, urban and biogenic sources. This study presents the first basin wide aircraft measurements of O3 during the dry-to-wet and wet-to-dry transition seasons, which show extremely low values above undisturbed forest and increases from fires. This work also demonstrates the capabilities and limitations of regional atmospheric chemistry models in representing O3 in Amazonia.
                                            
                                            
                                        M. Alexe, P. Bergamaschi, A. Segers, R. Detmers, A. Butz, O. Hasekamp, S. Guerlet, R. Parker, H. Boesch, C. Frankenberg, R. A. Scheepmaker, E. Dlugokencky, C. Sweeney, S. C. Wofsy, and E. A. Kort
                                    Atmos. Chem. Phys., 15, 113–133, https://doi.org/10.5194/acp-15-113-2015, https://doi.org/10.5194/acp-15-113-2015, 2015
                            B. Xiang, D. D. Nelson, J. B. McManus, M. S. Zahniser, R. A. Wehr, and S. C. Wofsy
                                    Atmos. Meas. Tech., 7, 4445–4453, https://doi.org/10.5194/amt-7-4445-2014, https://doi.org/10.5194/amt-7-4445-2014, 2014
                                    Short summary
                                    Short summary
                                            
                                                We designed and built a spectrometer, ABsolute Carbon dioxide (ABC), to measure atmospheric concentration of carbon dioxide. This instrument was tested in a forest environment for almost a year. Based on results from this long-term field deployment, we proved that ABC has the capability of performing high-accuracy, unattended, continuous field measurements with minimal use of reference gas cylinders.
                                            
                                            
                                        M. N. Deeter, S. Martínez-Alonso, D. P. Edwards, L. K. Emmons, J. C. Gille, H. M. Worden, C. Sweeney, J. V. Pittman, B. C. Daube, and S. C. Wofsy
                                    Atmos. Meas. Tech., 7, 3623–3632, https://doi.org/10.5194/amt-7-3623-2014, https://doi.org/10.5194/amt-7-3623-2014, 2014
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                                                The MOPITT Version 6 product for carbon monoxide (CO) incorporates several enhancements. First, a geolocation bias has been eliminated.  Second, the new variable a priori for CO concentrations is based on simulations performed with the CAM-Chem chemical transport model for the years 2000-2009.  Third, required meteorological fields are extracted from the MERRA reanalysis.  Finally, a retrieval bias in the upper troposphere was substantially reduced.  Validation results are presented.
                                            
                                            
                                        L. K. Meredith, R. Commane, J. W. Munger, A. Dunn, J. Tang, S. C. Wofsy, and R. G. Prinn
                                    Atmos. Meas. Tech., 7, 2787–2805, https://doi.org/10.5194/amt-7-2787-2014, https://doi.org/10.5194/amt-7-2787-2014, 2014
                            K. J. Wecht, D. J. Jacob, M. P. Sulprizio, G. W. Santoni, S. C. Wofsy, R. Parker, H. Bösch, and J. Worden
                                    Atmos. Chem. Phys., 14, 8173–8184, https://doi.org/10.5194/acp-14-8173-2014, https://doi.org/10.5194/acp-14-8173-2014, 2014
                            G. W. Santoni, B. C. Daube, E. A. Kort, R. Jiménez, S. Park, J. V. Pittman, E. Gottlieb, B. Xiang, M. S. Zahniser, D. D. Nelson, J. B. McManus, J. Peischl, T. B. Ryerson, J. S. Holloway, A. E. Andrews, C. Sweeney, B. Hall, E. J. Hintsa, F. L. Moore, J. W. Elkins, D. F. Hurst, B. B. Stephens, J. Bent, and S. C. Wofsy
                                    Atmos. Meas. Tech., 7, 1509–1526, https://doi.org/10.5194/amt-7-1509-2014, https://doi.org/10.5194/amt-7-1509-2014, 2014
                            F. Deng, D. B. A. Jones, D. K. Henze, N. Bousserez, K. W. Bowman, J. B. Fisher, R. Nassar, C. O'Dell, D. Wunch, P. O. Wennberg, E. A. Kort, S. C. Wofsy, T. Blumenstock, N. M. Deutscher, D. W. T. Griffith, F. Hase, P. Heikkinen, V. Sherlock, K. Strong, R. Sussmann, and T. Warneke
                                    Atmos. Chem. Phys., 14, 3703–3727, https://doi.org/10.5194/acp-14-3703-2014, https://doi.org/10.5194/acp-14-3703-2014, 2014
                            X. Xiong, C. Barnet, E. S. Maddy, A. Gambacorta, T. S. King, and S. C. Wofsy
                                    Atmos. Meas. Tech., 6, 2255–2265, https://doi.org/10.5194/amt-6-2255-2013, https://doi.org/10.5194/amt-6-2255-2013, 2013
                            B. Tuzson, K. Zeyer, M. Steinbacher, J. B. McManus, D. D. Nelson, M. S. Zahniser, and L. Emmenegger
                                    Atmos. Meas. Tech., 6, 927–936, https://doi.org/10.5194/amt-6-927-2013, https://doi.org/10.5194/amt-6-927-2013, 2013
                            J. Brioude, W. M. Angevine, R. Ahmadov, S.-W. Kim, S. Evan, S. A. McKeen, E.-Y. Hsie, G. J. Frost, J. A. Neuman, I. B. Pollack, J. Peischl, T. B. Ryerson, J. Holloway, S. S. Brown, J. B. Nowak, J. M. Roberts, S. C. Wofsy, G. W. Santoni, T. Oda, and M. Trainer
                                    Atmos. Chem. Phys., 13, 3661–3677, https://doi.org/10.5194/acp-13-3661-2013, https://doi.org/10.5194/acp-13-3661-2013, 2013
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                                SI-traceable validation of a laser spectrometer for balloon-borne measurements of water vapor in the upper atmosphere
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Field evaluation of low-cost electrochemical air quality gas sensors under extreme temperature and relative humidity conditions
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                A novel, cost-effective analytical method for measuring high-resolution vertical profiles of stratospheric trace gases using a gas chromatograph coupled with an electron capture detector
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Ethylene oxide monitor with part-per-trillion precision for in situ measurements
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Development of an automated pump-efficiency measuring system for ozonesondes utilizing an airbag-type flowmeter
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Short-term variability of atmospheric helium revealed through a cryo-enrichment method
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Using tunable infrared laser direct absorption spectroscopy for ambient hydrogen chloride detection: HCl-TILDAS
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                New methods for the calibration of optical resonators: integrated calibration by means of optical modulation (ICOM) and narrow-band cavity ring-down (NB-CRD)
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                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
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
            
        
        John Ericksen, Tobias P. Fischer, G. Matthew Fricke, Scott Nowicki, Nemesio M. Pérez, Pedro Hernández Pérez, Eleazar Padrón González, and Melanie E. Moses
                                    Atmos. Meas. Tech., 17, 4725–4736, https://doi.org/10.5194/amt-17-4725-2024, https://doi.org/10.5194/amt-17-4725-2024, 2024
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                                                Volcanic eruptions emit significant quantities of carbon dioxide (CO2) to the atmosphere. We present a new method for directly determining the CO2 emission from a volcanic eruption on the island of La Palma, Spain, using an unpiloted aerial vehicle (UAV). We also collected samples of the emitted CO2 and analyzed their isotopic composition. Together with the emission rate the isotopic data provide valuable information on the state of volcanic activity and the potential evolution of the eruption.
                                            
                                            
                                        László Haszpra
                                    Atmos. Meas. Tech., 17, 4629–4647, https://doi.org/10.5194/amt-17-4629-2024, https://doi.org/10.5194/amt-17-4629-2024, 2024
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                                                The paper evaluates a 30-year-long atmospheric CO2 data series from a mid-continental central European site, Hegyhátsál (HUN). It presents the site-specific features observed in the long-term evolution of the atmospheric CO2 concentration. Since the measurement data are widely used in atmospheric inverse models and budget calculations all around the world, the paper provides potentially valuable information for model tuning and interpretation of the model results.
                                            
                                            
                                        Mathieu Casado, Amaelle Landais, Tim Stoltmann, Justin Chaillot, Mathieu Daëron, Fréderic Prié, Baptiste Bordet, and Samir Kassi
                                    Atmos. Meas. Tech., 17, 4599–4612, https://doi.org/10.5194/amt-17-4599-2024, https://doi.org/10.5194/amt-17-4599-2024, 2024
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                                                Measuring water isotopic composition in Antarctica is difficult because of the extremely cold temperature in winter. Here, we designed a new infrared spectrometer able to measure the vapour isotopic composition during more than 95 % of the year in the coldest locations of Antarctica, whereas current commercial instruments are only able to measure during the warm summer months in the interior.
                                            
                                            
                                        Jean-Louis Bonne, Ludovic Donnat, Grégory Albora, Jérémie Burgalat, Nicolas Chauvin, Delphine Combaz, Julien Cousin, Thomas Decarpenterie, Olivier Duclaux, Nicolas Dumelié, Nicolas Galas, Catherine Juery, Florian Parent, Florent Pineau, Abel Maunoury, Olivier Ventre, Marie-France Bénassy, and Lilian Joly
                                    Atmos. Meas. Tech., 17, 4471–4491, https://doi.org/10.5194/amt-17-4471-2024, https://doi.org/10.5194/amt-17-4471-2024, 2024
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                                                We present a top-down approach to quantify CO2 and CH4 emissions at the scale of an industrial site, based on a mass balance model relying on atmospheric concentrations measurements from a new sensor embarked on board uncrewed aircraft vehicles (UAVs). We present a laboratory characterization of our sensor and a field validation of our quantification method, together with field application to the monitoring of two real-world offshore oil and gas platforms.
                                            
                                            
                                        Rodrigo Rivera-Martinez, Pramod Kumar, Olivier Laurent, Gregoire Broquet, Christopher Caldow, Ford Cropley, Diego Santaren, Adil Shah, Cécile Mallet, Michel Ramonet, Leonard Rivier, Catherine Juery, Olivier Duclaux, Caroline Bouchet, Elisa Allegrini, Hervé Utard, and Philippe Ciais
                                    Atmos. Meas. Tech., 17, 4257–4290, https://doi.org/10.5194/amt-17-4257-2024, https://doi.org/10.5194/amt-17-4257-2024, 2024
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                                                We explore the use of metal oxide semiconductors (MOSs) as a low-cost alternative for detecting and measuring CH4 emissions from industrial facilities. MOSs were exposed to several controlled releases to test their accuracy in detecting and quantifying emissions. Two reconstruction models were compared, and emission estimates were computed using a Gaussian dispersion model. Findings show that MOSs can provide accurate emission estimates with a 25 % emission rate error and a 9.5 m location error.
                                            
                                            
                                        Zihan Zhu, Javier González-Rocha, Yifan Ding, Isis Frausto-Vicencio, Sajjan Heerah, Akula Venkatram, Manvendra Dubey, Don Collins, and Francesca M. Hopkins
                                    Atmos. Meas. Tech., 17, 3883–3895, https://doi.org/10.5194/amt-17-3883-2024, https://doi.org/10.5194/amt-17-3883-2024, 2024
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                                                Increases in agriculture, oil and gas, and waste management activities have contributed to the increase in atmospheric methane levels and resultant climate warming. In this paper, we explore the use of small uncrewed aircraft systems (sUASs) and AirCore technology to detect and quantify methane emissions. Results from field experiments demonstrate that sUASs and AirCore technology can be effective for detecting and quantifying methane emissions in near real time.
                                            
                                            
                                        Sebastian Diez, Stuart Lacy, Hugh Coe, Josefina Urquiza, Max Priestman, Michael Flynn, Nicholas Marsden, Nicholas A. Martin, Stefan Gillott, Thomas Bannan, and Pete M. Edwards
                                    Atmos. Meas. Tech., 17, 3809–3827, https://doi.org/10.5194/amt-17-3809-2024, https://doi.org/10.5194/amt-17-3809-2024, 2024
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                                                In this paper we present an overview of the QUANT project, which to our knowledge is one of the largest evaluations of commercial sensors to date. The objective was to evaluate the performance of a range of commercial products and also to nourish the different applications in which these technologies can offer relevant information.
                                            
                                            
                                        Linda Ort, Lenard Lukas Röder, Uwe Parchatka, Rainer Königstedt, Daniel Crowley, Frank Kunz, Ralf Wittkowski, Jos Lelieveld, and Horst Fischer
                                    Atmos. Meas. Tech., 17, 3553–3565, https://doi.org/10.5194/amt-17-3553-2024, https://doi.org/10.5194/amt-17-3553-2024, 2024
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                                                Airborne in situ measurements are of great importance to collect valuable data to improve our knowledge of the atmosphere but also present challenges which demand specific designs. This study presents an IR spectrometer for airborne trace-gas measurements with high data efficiency and a simple, compact design. Its in-flight performance is characterized with the help of a test flight and a comparison with another spectrometer. Moreover, results from its first campaign highlight its benefits.
                                            
                                            
                                        Steven A. Bailey, Reem A. Hannun, Andrew K. Swanson, and Thomas F. Hanisco
                                        Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-61, https://doi.org/10.5194/amt-2024-61, 2024
                                    Revised manuscript accepted for AMT 
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                                                We have developed a portable, optically based instrument that measures NO2. It consumes less than 6 watts of power so can easily run off a small battery. This instrument has made both balloon and UAV flights. NO2 measurement results compare favorably with other known NO2 instruments. We find this instrument to be stable with repeatable results compared with calibration sources. Materials cost to build a single instrument is around $4 k. This number could be lowered with economies of scale.
                                            
                                            
                                        Roger Curcoll, Claudia Grossi, Stefan Röttger, and Arturo Vargas
                                    Atmos. Meas. Tech., 17, 3047–3065, https://doi.org/10.5194/amt-17-3047-2024, https://doi.org/10.5194/amt-17-3047-2024, 2024
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                                                This paper presents a new user-friendly version of the Atmospheric Radon MONitor (ARMON). The efficiency of the instrument is of 0.0057 s-1, obtained using different techniques at Spanish and German chambers. The total calculated uncertainty of the ARMON for hourly radon concentrations above 5 Bq m-3 is lower than 10 % (k = 1). Results confirm that the ARMON is suitable to measure low-level radon activity concentrations and to be used as a transfer standard to calibrate in situ radon monitors.
                                            
                                            
                                        Josie K. Radtke, Benjamin N. Kies, Whitney A. Mottishaw, Sydney M. Zeuli, Aidan T. H. Voon, Kelly L. Koerber, Grant W. Petty, Michael P. Vermeuel, Timothy H. Bertram, Ankur R. Desai, Joseph P. Hupy, R. Bradley Pierce, Timothy J. Wagner, and Patricia A. Cleary
                                    Atmos. Meas. Tech., 17, 2833–2847, https://doi.org/10.5194/amt-17-2833-2024, https://doi.org/10.5194/amt-17-2833-2024, 2024
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                                                The use of uncrewed aircraft systems (UASs) to conduct a vertical profiling of ozone and meteorological variables was evaluated using comparisons between tower or ground observations and UAS-based measurements. Changes to the UAS profiler showed an improvement in performance. The profiler was used to see the impact of Chicago pollution plumes on a shoreline area near Lake Michigan.
                                            
                                            
                                        Chen-Wei Liang and Chang-Hung Shen
                                    Atmos. Meas. Tech., 17, 2671–2686, https://doi.org/10.5194/amt-17-2671-2024, https://doi.org/10.5194/amt-17-2671-2024, 2024
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                                                In the present study, a UAV platform with sensing and sampling systems was developed for 3D air pollutant concentration measurements. The sensing system of this platform contains multiple microsensors and IoT technologies for obtaining the real-time 3D distributions of critical air pollutants. The sampling system contains gas sampling sets and a 1 L Tedlar bag instead of a canister for the 3D measurement of VOC concentrations in accordance with the TO-15 method of the US EPA.
                                            
                                            
                                        Abdullah Bolek, Martin Heimann, and Mathias Goeckede
                                        Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-74, https://doi.org/10.5194/amt-2024-74, 2024
                                    Revised manuscript accepted for AMT 
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                                                This study describes the development of a new UAV platform to measure atmospheric greenhouse gas (GHG) mole fractions, 2D wind speed, air temperature, humidity, and pressure. Understanding GHG flux processes and controls across various ecosystems is essential for estimating the current and future state of climate change. It was shown that using the UAV platform for such measurements is beneficial for improving our understanding of GHG processes over complex landscapes.
                                            
                                            
                                        Daniel Furuta, Bruce Wilson, Albert A. Presto, and Jiayu Li
                                    Atmos. Meas. Tech., 17, 2103–2121, https://doi.org/10.5194/amt-17-2103-2024, https://doi.org/10.5194/amt-17-2103-2024, 2024
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                                                Methane is an important driver of climate change and is challenging to inexpensively sense in low atmospheric concentrations. We developed a low-cost sensor to monitor methane and tested it in indoor and outdoor settings. Our device shows promise for monitoring low levels of methane. We characterize its limitations and suggest future research directions for further development.
                                            
                                            
                                        Audrey J. Dang, Nathan M. Kreisberg, Tyler L. Cargill, Jhao-Hong Chen, Sydney Hornitschek, Remy Hutheesing, Jay R. Turner, and Brent J. Williams
                                    Atmos. Meas. Tech., 17, 2067–2087, https://doi.org/10.5194/amt-17-2067-2024, https://doi.org/10.5194/amt-17-2067-2024, 2024
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                                                The Multichannel Organics In situ enviRonmental Analyzer (MOIRA) is a new instrument for measuring speciated volatile organic compounds (VOCs) in the air and has been developed for mapping concentrations from a hybrid car. MOIRA is characterized in the lab and pilot field studies of indoor air in a single-family residence and outdoor air during a mobile deployment. Future applications include indoor, outdoor, and lab measurements to grasp the impact of VOCs on air quality, health, and climate.
                                            
                                            
                                        Asher P. Mouat, Zelda A. Siegel, and Jennifer Kaiser
                                    Atmos. Meas. Tech., 17, 1979–1994, https://doi.org/10.5194/amt-17-1979-2024, https://doi.org/10.5194/amt-17-1979-2024, 2024
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                                                Three fast-measurement formaldehyde monitors were deployed at two field sites in Atlanta, GA, over 1 year. Four different zeroing methods were tested to develop an optimal field setup as well as procedures for instrument calibration. Observations agreed well after calibration but were much higher compared to the TO-11A monitoring method, which is the golden standard. Historical HCHO concentrations were compared with measurements in this work, showing a 22 % reduction in midday HCHO since 1999.
                                            
                                            
                                        Henning Finkenzeller, Jyri Mikkilä, Cecilia Righi, Paxton Juuti, Mikko Sipilä, Matti Rissanen, Douglas Worsnop, Aleksei Shcherbinin, Nina Sarnela, and Juha Kangasluoma
                                        Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-48, https://doi.org/10.5194/amt-2024-48, 2024
                                    Revised manuscript accepted for AMT 
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                                                Chemical ionization mass spectrometry is used in atmospheric sciences to measure trace gas concentrations. Neutral gases require charging in inlets before the mass-to-charge ratio of the resulting ions can be analyzed. This study uses multi-physics modelling to investigate how the MION2 and Eisele type inlets work, shows the effect of tuning parameters, and their current limitations. The findings are helpful for the inlet users and are expected to aid in developing improved inlets.
                                            
                                            
                                        Jonathan F. Dooley, Kenneth Minschwaner, Manvendra K. Dubey, Sahar H. El Abbadi, Evan D. Sherwin, Aaron G. Meyer, Emily Follansbee, and James E. Lee
                                        EGUsphere, https://doi.org/10.5194/egusphere-2024-760, https://doi.org/10.5194/egusphere-2024-760, 2024
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                                                Methane is a powerful greenhouse gas originating from both natural and human activities. We describe a new Unmanned Aerial System (UAS) designed to measure methane emission rates from over a wide range of scales. This system has been used for direct quantification of point sources and distributed emitters over scales of up to 1 km. The system uses simultaneous measurements of methane and ethane to distinguish between different kinds of natural and human-related emission sources.
                                            
                                            
                                        Da Yang, Margarita Reza, Roy Mauldin, Rainer Volkamer, and Suresh Dhaniyala
                                    Atmos. Meas. Tech., 17, 1463–1474, https://doi.org/10.5194/amt-17-1463-2024, https://doi.org/10.5194/amt-17-1463-2024, 2024
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                                                This paper evaluates the performance of an aircraft gas inlet. Here, we use computational fluid dynamics (CFD) and experiments to demonstrate the role of turbulence in determining sampling performance of a gas inlet and identify ideal conditions for inlet operation to minimize gas loss. Experiments conducted in a high-speed wind tunnel under near-aircraft speeds validated numerical results. We believe that the results obtained from this work will greatly inform future gas inlet studies.
                                            
                                            
                                        Reena Macagga, Michael Asante, Geoffroy Sossa, Danica Antonijević, Maren Dubbert, and Mathias Hoffmann
                                    Atmos. Meas. Tech., 17, 1317–1332, https://doi.org/10.5194/amt-17-1317-2024, https://doi.org/10.5194/amt-17-1317-2024, 2024
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                                                Using only low-cost microcontrollers and sensors, we constructed a measurement device to accurately and precisely obtain atmospheric carbon dioxide and water fluxes. The device was tested against known concentration increases and high-cost, commercial sensors during a laboratory and field experiment. We additionally tested the device over a longer period in a field study in Ghana during which the net ecosystem carbon balance and water use efficiency of maize cultivation were studied.
                                            
                                            
                                        Matthew M. Coggon, Chelsea E. Stockwell, Megan S. Claflin, Eva Y. Pfannerstill, Lu Xu, Jessica B. Gilman, Julia Marcantonio, Cong Cao, Kelvin Bates, Georgios I. Gkatzelis, Aaron Lamplugh, Erin F. Katz, Caleb Arata, Eric C. Apel, Rebecca S. Hornbrook, Felix Piel, Francesca Majluf, Donald R. Blake, Armin Wisthaler, Manjula Canagaratna, Brian M. Lerner, Allen H. Goldstein, John E. Mak, and Carsten Warneke
                                    Atmos. Meas. Tech., 17, 801–825, https://doi.org/10.5194/amt-17-801-2024, https://doi.org/10.5194/amt-17-801-2024, 2024
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                                                Mass spectrometry is a tool commonly used to measure air pollutants. This study evaluates measurement artifacts produced in the proton-transfer-reaction mass spectrometer. We provide methods to correct these biases and better measure compounds that degrade air quality.
                                            
                                            
                                        Tianran Han, Conghui Xie, Yayong Liu, Yanrong Yang, Yuheng Zhang, Yufei Huang, Xiangyu Gao, Xiaohua Zhang, Fangmin Bao, and Shao-Meng Li
                                    Atmos. Meas. Tech., 17, 677–691, https://doi.org/10.5194/amt-17-677-2024, https://doi.org/10.5194/amt-17-677-2024, 2024
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                                                This study reported an integrated UAV measurement platform for GHG monitoring and its application for emission quantification from a coking plant. The key element of this system is a newly designed air sampler, consisting of a 150 m long tube with remote-controlled time stamping. When comparing the top-down results to those derived from the bottom-up inventory method, the present findings indicate that the use of IPCC emission factors for emission calculations can lead to overestimation.
                                            
                                            
                                        Yuening Li, Faqiang Zhan, Yushan Su, Ying Duan Lei, Chubashini Shunthirasingham, Zilin Zhou, Jonathan P. D. Abbatt, Hayley Hung, and Frank Wania
                                    Atmos. Meas. Tech., 17, 715–729, https://doi.org/10.5194/amt-17-715-2024, https://doi.org/10.5194/amt-17-715-2024, 2024
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                                                A simple device for sampling gases from the atmosphere without the help of pumps was calibrated for an important group of hazardous air pollutants called polycyclic aromatic compounds (PACs). While the sampler appeared to perform well when used for relatively short periods of up to several months, some PACs were lost from the sampler during longer deployments. Sampling rates that can be used to quantitatively interpret the quantities of PACs taken up in the device have been derived.
                                            
                                            
                                        Jinghui Lian, Olivier Laurent, Mali Chariot, Luc Lienhardt, Michel Ramonet, Hervé Utard, Thomas Lauvaux, François-Marie Bréon, Grégoire Broquet, Karina Cucchi, Laurent Millair, and Philippe Ciais
                                        EGUsphere, https://doi.org/10.5194/egusphere-2024-125, https://doi.org/10.5194/egusphere-2024-125, 2024
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                                                We have designed and deployed a mid-cost medium-precision CO2 sensor monitoring network in Paris since July 2020. The data are automatically calibrated by a newly implemented data processing system. The accuracies of the mid-cost instruments vary from 1.0 to 2.4 ppm for hourly afternoon measurements. Our model-data analyses highlight prospects for integrating mid-cost instrument data with high-precision measurements to improve fine-scale CO2 emission quantification in urban areas.
                                            
                                            
                                        Jiaxin Li, Kunpeng Zang, Yi Lin, Yuanyuan Chen, Shuo Liu, Shanshan Qiu, Kai Jiang, Xuemei Qing, Haoyu Xiong, Haixiang Hong, Shuangxi Fang, Honghui Xu, and Yujun Jiang
                                    Atmos. Meas. Tech., 16, 4757–4768, https://doi.org/10.5194/amt-16-4757-2023, https://doi.org/10.5194/amt-16-4757-2023, 2023
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                                                Based on observed data of CO2 and CH4 and meteorological parameters over the Yellow Sea in November 2012 and June 2013, a data process and quality control method was optimized and established to filter the data influenced by multiple factors. Spatial and seasonal variations in CO2 and CH4 mixing ratios were mainly controlled by the East Asian Monsoon, while the influence of air–sea exchange was slight.
                                            
                                            
                                        Zaneta Hamryszczak, Antonia Hartmann, Dirk Dienhart, Sascha Hafermann, Bettina Brendel, Rainer Königstedt, Uwe Parchatka, Jos Lelieveld, and Horst Fischer
                                    Atmos. Meas. Tech., 16, 4741–4756, https://doi.org/10.5194/amt-16-4741-2023, https://doi.org/10.5194/amt-16-4741-2023, 2023
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                                                Hydroperoxide measurements improve the understanding of atmospheric oxidation processes. We introduce an instrumental setup for airborne measurements. The aim of the work is the characterization of the measurement method with emphasis on interferences impacting instrumental uncertainty. Technical and physical challenges do not critically impact the instrumental performance. The instrument resolves dynamic processes, such as convective transport, as shown based on the CAFE-Brazil campaign.
                                            
                                            
                                        James F. Hurley, Alejandra Caceres, Deborah F. McGlynn, Mary E. Tovillo, Suzanne Pinar, Roger Schürch, Ksenia Onufrieva, and Gabriel Isaacman-VanWertz
                                    Atmos. Meas. Tech., 16, 4681–4692, https://doi.org/10.5194/amt-16-4681-2023, https://doi.org/10.5194/amt-16-4681-2023, 2023
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                                                Volatile organic compounds (VOCs) have a wide range of sources and impacts on environments and human health that make them spatially, temporally, and chemically varied. Current methods lack the ability to collect samples in ways that provide spatial and chemical resolution without complex, costly instrumentation. We describe and validate a low-cost, portable VOC sampler and demonstrate its utility in collecting distributed coordinated samples.
                                            
                                            
                                        Simone Brunamonti, Manuel Graf, Tobias Bühlmann, Céline Pascale, Ivan Ilak, Lukas Emmenegger, and Béla Tuzson
                                    Atmos. Meas. Tech., 16, 4391–4407, https://doi.org/10.5194/amt-16-4391-2023, https://doi.org/10.5194/amt-16-4391-2023, 2023
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                                                The abundance of water vapor (H2O) in the upper atmosphere has a significant impact on the rate of global warming. We developed a new lightweight spectrometer (ALBATROSS) for H2O measurements aboard meteorological balloons. Here, we assess the accuracy and precision of ALBATROSS using metrology-grade reference gases. The results demonstrate the exceptional potential of mid-infrared laser absorption spectroscopy as a new reference method for in situ measurements of H2O in the upper atmosphere.
                                            
                                            
                                        Roubina Papaconstantinou, Marios Demosthenous, Spyros Bezantakos, Neoclis Hadjigeorgiou, Marinos Costi, Melina Stylianou, Elli Symeou, Chrysanthos Savvides, and George Biskos
                                    Atmos. Meas. Tech., 16, 3313–3329, https://doi.org/10.5194/amt-16-3313-2023, https://doi.org/10.5194/amt-16-3313-2023, 2023
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                                                In this paper, we investigate the performance of low-cost electrochemical gas sensors. We carried out yearlong measurements at a traffic air quality monitoring station, where the low-cost sensors were collocated with reference instruments and exposed to highly variable environmental conditions with extremely high temperatures and low relative humidity (RH). Sensors provide measurements that exhibit increasing errors and decreasing correlations as temperature increases and RH decreases.
                                            
                                            
                                        Jianghanyang Li, Bianca C. Baier, Fred Moore, Tim Newberger, Sonja Wolter, Jack Higgs, Geoff Dutton, Eric Hintsa, Bradley Hall, and Colm Sweeney
                                    Atmos. Meas. Tech., 16, 2851–2863, https://doi.org/10.5194/amt-16-2851-2023, https://doi.org/10.5194/amt-16-2851-2023, 2023
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                                                Monitoring a suite of trace gases in the stratosphere will help us better understand the stratospheric circulation and its impact on the earth's radiation balance. However, such measurements are rare and usually expensive. We developed an instrument that can measure stratospheric trace gases using a low-cost sampling platform (AirCore). The results showed expected agreement with aircraft measurements, demonstrating this technique provides a low-cost and robust way to observe the stratosphere.
                                            
                                            
                                        Tara I. Yacovitch, Christoph Dyroff, Joseph R. Roscioli, Conner Daube, J. Barry McManus, and Scott C. Herndon
                                    Atmos. Meas. Tech., 16, 1915–1921, https://doi.org/10.5194/amt-16-1915-2023, https://doi.org/10.5194/amt-16-1915-2023, 2023
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                                                Ethylene oxide is a toxic, carcinogenic compound used in the medical and bulk sterilization industry. Here we describe a precise and fast laser-based ethylene oxide monitor. We report months-long concentrations at a Massachusetts site, and we show how they suggest a potential emission source 35 km away. This source, and another, is confirmed by driving the instrument downwind of the sites, where concentrations were tens to tens of thousands of times greater than background levels.
                                            
                                            
                                        Tatsumi Nakano and Takashi Morofuji
                                    Atmos. Meas. Tech., 16, 1583–1595, https://doi.org/10.5194/amt-16-1583-2023, https://doi.org/10.5194/amt-16-1583-2023, 2023
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                                                We have developed a system that can automatically measure the pump efficiency of the ECC-type ozonesonde. Operational measurement for 13 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.
                                            
                                            
                                        Benjamin Birner, Eric Morgan, and Ralph F. Keeling
                                    Atmos. Meas. Tech., 16, 1551–1561, https://doi.org/10.5194/amt-16-1551-2023, https://doi.org/10.5194/amt-16-1551-2023, 2023
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                                                Atmospheric variations of helium (He) and CO2 are strongly linked due to the co-release of both gases from natural-gas burning. This implies that 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.
                                            
                                            
                                        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., 16, 1407–1429, https://doi.org/10.5194/amt-16-1407-2023, https://doi.org/10.5194/amt-16-1407-2023, 2023
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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.
                                            
                                            
                                        Henning Finkenzeller, Denis Pöhler, Martin Horbanski, Johannes Lampel, and Ulrich Platt
                                    Atmos. Meas. Tech., 16, 1343–1356, https://doi.org/10.5194/amt-16-1343-2023, https://doi.org/10.5194/amt-16-1343-2023, 2023
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                                                Optical resonators enhance the light path in compact instruments, thereby improving their 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.
                                            
                                            
                                        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.
                                            
                                            
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