Articles | Volume 13, issue 6
Research article 30 Jun 2020
Research article | 30 Jun 2020
Mobile-platform measurement of air pollutant concentrations in California: performance assessment, statistical methods for evaluating spatial variations, and spatial representativeness
Paul A. Solomon et al.
No articles found.
Alexandra J. Boris, Satoshi Takahama, Andrew T. Weakley, Bruno M. Debus, Stephanie L. Shaw, Eric S. Edgerton, Taekyu Joo, Nga L. Ng, and Ann M. Dillner
Atmos. Meas. Tech., 14, 4355–4374,Short summary
Infrared spectrometry can be applied in routine monitoring of atmospheric particles to give comprehensive characterization of the organic material by bond rather than species. Using this technique, the concentrations of particle organic material were found to decrease 2011–2016 in the southeastern US, driven by a decline in highly aged material, concurrent with declining anthropogenic emissions. However, an increase was observed in the fraction of more moderately aged organic matter.
Charlotte Bürki, Matteo Reggente, Ann M. Dillner, Jenny L. Hand, Stephanie L. Shaw, and Satoshi Takahama
Atmos. Meas. Tech., 13, 1517–1538,Short summary
Infrared spectroscopy is a chemically informative method for particulate matter characterization. However, recent work has demonstrated that predictions depend heavily on the choice of calibration model parameters. We propose a means for managing parameter uncertainties by combining available data from laboratory standards, molecular databases, and collocated ambient measurements to provide useful characterization of atmospheric organic matter on a large scale.
Alexandra J. Boris, Satoshi Takahama, Andrew T. Weakley, Bruno M. Debus, Carley D. Fredrickson, Martin Esparza-Sanchez, Charlotte Burki, Matteo Reggente, Stephanie L. Shaw, Eric S. Edgerton, and Ann M. Dillner
Atmos. Meas. Tech., 12, 5391–5415,Short summary
Organic species are abundant in atmospheric particle-phase (aerosol) pollution and originate from a variety of biogenic and anthropogenic sources. Infrared spectrometry of filter-based atmospheric particle samples can afford a direct measurement of the particulate organic matter concentration and a characterization of its composition. This work discusses recent method improvements and compositions measured in samples from the SouthEastern Aerosol Research and Characterization (SEARCH) network.
Charles L. Blanchard and George M. Hidy
Atmos. Chem. Phys., 18, 8183–8202,Short summary
Ozone (O3) formation in the southeastern US was studied in relation to nitrogen oxide (NOx) emissions using long-term (1990s–2015) measurements of the SEARCH network and U.S. EPA data. NOx emissions decreased by ~ 60 %. Annual fourth-highest daily peak 8 h O3 mixing ratios declined toward ~ 45–50 ppbv at ~1 ppbv yr−1 and O3 exhibited increasing sensitivity to NOx. This study illustrates the value of consistent, long-term measurements of O3 and reactive nitrogen made at both urban and rural sites.
Sri Hapsari Budisulistiorini, Karsten Baumann, Eric S. Edgerton, Solomon T. Bairai, Stephen Mueller, Stephanie L. Shaw, Eladio M. Knipping, Avram Gold, and Jason D. Surratt
Atmos. Chem. Phys., 16, 5171–5189,Short summary
A year-long near-real-time characterization of non-refractory submicron aerosol (NR-PM1) was conducted at an urban (Atlanta, Georgia, in 2012) and rural (Look Rock, Tennessee, in 2013) site in the southeastern US using the Aerodyne Aerosol Chemical Speciation Monitor, collocated with established air-monitoring network measurements, to identify sources of organic aerosol (OA). Further, high-volume filter samples were collected for measurements of OA tracers by offline mass spectrometry tools.
Weruka Rattanavaraha, Kevin Chu, Sri Hapsari Budisulistiorini, Matthieu Riva, Ying-Hsuan Lin, Eric S. Edgerton, Karsten Baumann, Stephanie L. Shaw, Hongyu Guo, Laura King, Rodney J. Weber, Miranda E. Neff, Elizabeth A. Stone, John H. Offenberg, Zhenfa Zhang, Avram Gold, and Jason D. Surratt
Atmos. Chem. Phys., 16, 4897–4914,Short summary
The mechanisms by which specific anthropogenic pollutants enhance isoprene SOA in ambient PM2.5 remain unclear. As one aspect of an investigation to examine how anthropogenic pollutants influence isoprene-derived SOA formation, high-volume PM2.5 filter samples were collected from Birmingham, AL, during the 2013 Southern Oxidant and Aerosol Study (SOAS). Isoprene SOA tracers were measured from these samples and compared to gas and aerosol data collected from the SEARCH network.
C. L. Blanchard, G. M. Hidy, S. Shaw, K. Baumann, and E. S. Edgerton
Atmos. Chem. Phys., 16, 215–238,Short summary
Fifteen years of gas and particle measurements at eight monitoring sites comprising the Southeastern Aerosol Research and Characterization (SEARCH) network offer insights into the sources of organic aerosol in the southeastern United States. Between 1999 and 2013, mean organic aerosol concentrations declined due to decreasing particle emissions from motor vehicles and to less secondary organic aerosol with declining emissions of sulfur dioxide, nitrogen oxides, and volatile organic compounds.
S. H. Budisulistiorini, X. Li, S. T. Bairai, J. Renfro, Y. Liu, Y. J. Liu, K. A. McKinney, S. T. Martin, V. F. McNeill, H. O. T. Pye, A. Nenes, M. E. Neff, E. A. Stone, S. Mueller, C. Knote, S. L. Shaw, Z. Zhang, A. Gold, and J. D. Surratt
Atmos. Chem. Phys., 15, 8871–8888,Short summary
Isoprene epoxydiols (IEPOX) are major gas-phase products from the atmospheric oxidation of isoprene that yield secondary organic aerosol (SOA) by reactive uptake onto acidic sulfate aerosol. We report a substantial contribution of IEPOX-derived SOA to the total fine aerosol collected during summer. IEPOX-derived SOA measured by online and offline mass spectrometry techniques is correlated with acidic sulfate aerosol, demonstrating the critical role of anthropogenic emissions in its formation.
G. M. Hidy, C. L. Blanchard, K. Baumann, E. Edgerton, S. Tanenbaum, S. Shaw, E. Knipping, I. Tombach, J. Jansen, and J. Walters
Atmos. Chem. Phys., 14, 11893–11914,Short summary
This paper reviews aerometric measurements from Centreville, Alabama. The measurements show annual trends with air pollution emissions from 1999 to 2013. They provide a context for observations from 1 June to 15 July 2013 supporting the Southern Oxidant and Aerosol Study. An important goal of this experiment was to advance knowledge of aerosols produced in the atmosphere from precursors. The observations were in moist and warm conditions with the lowest gas and particle concentrations recorded.
S. H. Budisulistiorini, M. R. Canagaratna, P. L. Croteau, K. Baumann, E. S. Edgerton, M. S. Kollman, N. L. Ng, V. Verma, S. L. Shaw, E. M. Knipping, D. R. Worsnop, J. T. Jayne, R.J. Weber, and J. D. Surratt
Atmos. Meas. Tech., 7, 1929–1941,
Related subject area
Subject: Gases | Technique: In Situ Measurement | Topic: Validation and IntercomparisonsComparison of formaldehyde measurements by Hantzsch, CRDS and DOAS in the SAPHIR chamberA field intercomparison of three passive air samplers for gaseous mercury in ambient airBeef cattle methane emissions measured with tracer-ratio and inverse dispersion modelling techniquesMethane emissions from an oil sands tailings pond: a quantitative comparison of fluxes derived by different methodsPerformance of open-path GasFinder3 devices for CH4 concentration measurements close to ambient levelsWater vapor density and turbulent fluxes from three generations of infrared gas analyzersQuantifying fugitive gas emissions from an oil sands tailings pond with open-path Fourier transform infrared measurementsRobust statistical calibration and characterization of portable low-cost air quality monitoring sensors to quantify real-time O3 and NO2 concentrations in diverse environmentsA miniature Portable Emissions Measurement System (PEMS) for real-driving monitoring of motorcyclesIn situ measurement of CO2 and CH4 from aircraft over northeast China and comparison with OCO-2 dataContinuous methane concentration measurements at the Greenland ice sheet–atmosphere interface using a low-cost, low-power metal oxide sensor systemThe development of the Atmospheric Measurements by Ultra-Light Spectrometer (AMULSE) greenhouse gas profiling system and application for satellite retrieval validationAtmospheric observations of the water vapour continuum in the near-infrared windows between 2500 and 6600 cm−1Intercomparison study of atmospheric 222Rn and 222Rn progeny monitorsSources of error in open-path FTIR measurements of N2O and CO2 emitted from agricultural fieldsConstraining the accuracy of flux estimates using OTM 33AEvaluating the measurement interference of wet rotating-denuder–ion chromatography in measuring atmospheric HONO in a highly polluted areaIntercomparison of nitrous acid (HONO) measurement techniques in a megacity (Beijing)Validity and limitations of simple reaction kinetics to calculate concentrations of organic compounds from ion counts in PTR-MSRecent advances in measurement techniques for atmospheric carbon monoxide and nitrous oxide observationsTrue eddy accumulation trace gas flux measurements: proof of conceptSimultaneous detection of C2H6, CH4, and δ13C-CH4 using optical feedback cavity-enhanced absorption spectroscopy in the mid-infrared region: towards application for dissolved gas measurementsAn improved low-power measurement of ambient NO2 and O3 combining electrochemical sensor clusters and machine learningComparison of slant open-path flux gradient and static closed chamber techniques to measure soil N2O emissionsField measurements of methylglyoxal using proton transfer reaction time-of-flight mass spectrometry and comparison to the DNPH–HPLC–UV methodHow well can global chemistry models calculate the reactivity of short-lived greenhouse gases in the remote troposphere, knowing the chemical compositionEstimation of nocturnal CO2 and N2O soil emissions from changes in surface boundary layer mass storageIntra-urban spatial variability of surface ozone in Riverside, CA: viability and validation of low-cost sensorsField calibration of electrochemical NO2 sensors in a citizen science contextCalibration and field testing of cavity ring-down laser spectrometers measuring CH4, CO2, and δ13CH4 deployed on towers in the Marcellus Shale regionCalibration and assessment of electrochemical air quality sensors by co-location with regulatory-grade instrumentsComparison of VOC measurements made by PTR-MS, adsorbent tubes–GC-FID-MS and DNPH derivatization–HPLC during the Sydney Particle Study, 2012: a contribution to the assessment of uncertainty in routine atmospheric VOC measurementsMeasurement of interferences associated with the detection of the hydroperoxy radical in the atmosphere using laser-induced fluorescenceMeasurements of a potential interference with laser-induced fluorescence measurements of ambient OH from the ozonolysis of biogenic alkenesStatistical atmospheric inversion of local gas emissions by coupling the tracer release technique and local-scale transport modelling: a test case with controlled methane emissionsComparison of OH reactivity measurements in the atmospheric simulation chamber SAPHIRUse of electrochemical sensors for measurement of air pollution: correcting interference response and validating measurementsObservations of VOC emissions and photochemical products over US oil- and gas-producing regions using high-resolution H3O+ CIMS (PTR-ToF-MS)Simultaneous multicopter-based air sampling and sensing of meteorological variablesEvaluation and environmental correction of ambient CO2 measurements from a low-cost NDIR sensorA closed-chamber method to measure greenhouse gas fluxes from dry aquatic sedimentsMethods to homogenize electrochemical concentration cell (ECC) ozonesonde measurements across changes in sensing solution concentration or ozonesonde manufacturerComparison of optical-feedback cavity-enhanced absorption spectroscopy and gas chromatography for ground-based and airborne measurements of atmospheric CO concentrationA European-wide 222radon and 222radon progeny comparison studyAn eddy-covariance system with an innovative vortex intake for measuring carbon dioxide and water fluxes of ecosystemsFlux calculation of short turbulent events – comparison of three methodsUsing in situ GC-MS for analysis of C2–C7 volatile organic acids in ambient air of a boreal forest siteMeasuring OVOCs and VOCs by PTR-MS in an urban roadside microenvironment of Hong Kong: relative humidity and temperature dependence, and field intercomparisonsComparison of two closed-path cavity-based spectrometers for measuring air–water CO2 and CH4 fluxes by eddy covarianceA comparison of very short lived halocarbon (VSLS) and DMS aircraft measurements in the tropical west Pacific from CAST, ATTREX and CONTRAST
Marvin Glowania, Franz Rohrer, Hans-Peter Dorn, Andreas Hofzumahaus, Frank Holland, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Meas. Tech., 14, 4239–4253,Short summary
Three instruments that use different techniques to measure gaseous formaldehyde concentrations were compared in experiments in the atmospheric simulation chamber SAPHIR at Forschungszentrum Jülich. The results demonstrated the need to correct the baseline in measurements by instruments that use the Hantzsch reaction or make use of cavity ring-down spectroscopy. After applying corrections, all three methods gave accurate and precise measurements within their specifications.
Attilio Naccarato, Antonella Tassone, Maria Martino, Sacha Moretti, Antonella Macagnano, Emiliano Zampetti, Paolo Papa, Joshua Avossa, Nicola Pirrone, Michelle Nerentorp, John Munthe, Ingvar Wängberg, Geoff W. Stupple, Carl P. J. Mitchell, Adam R. Martin, Alexandra Steffen, Diana Babi, Eric M. Prestbo, Francesca Sprovieri, and Frank Wania
Atmos. Meas. Tech., 14, 3657–3672,Short summary
Mercury monitoring in support of the Minamata Convention requires effective and reliable analytical tools. Passive sampling is a promising approach for creating a sustainable long-term network for atmospheric mercury with improved spatial resolution and global coverage. In this study the analytical performance of three passive air samplers (CNR-PAS, IVL-PAS, and MerPAS) was assessed over extended deployment periods and the accuracy of concentrations was judged by comparison with active sampling.
Mei Bai, José I. Velazco, Trevor W. Coates, Frances A. Phillips, Thomas K. Flesch, Julian Hill, David G. Mayer, Nigel W. Tomkins, Roger S. Hegarty, and Deli Chen
Atmos. Meas. Tech., 14, 3469–3479,Short summary
The development and validation of management practices to mitigate methane (CH4) emissions from livestock require accurate emission measurements. We compared the inverse dispersion modelling (IDM) and tracer-ratio techniques to measure CH4 emissions from cattle. Both measurements agreed well but were higher than IPCC estimates. We suggest that the IDM approach can provide an accurate method of estimating cattle emissions, and IPCC estimates may have larger uncertainties.
Yuan You, Ralf M. Staebler, Samar G. Moussa, James Beck, and Richard L. Mittermeier
Atmos. Meas. Tech., 14, 1879–1892,Short summary
Tailings ponds in the Alberta oil sands can be significant sources of methane, an important greenhouse gas. This paper describes a 1-month study conducted in 2017 to measure methane emissions from a pond using a variety of micrometeorological flux methods and demonstrates some advantages of these methods over flux chambers.
Christoph Häni, Marcel Bühler, Albrecht Neftel, Christof Ammann, and Thomas Kupper
Atmos. Meas. Tech., 14, 1733–1741,
Seth Kutikoff, Xiaomao Lin, Steven R. Evett, Prasanna Gowda, David Brauer, Jerry Moorhead, Gary Marek, Paul Colaizzi, Robert Aiken, Liukang Xu, and Clenton Owensby
Atmos. Meas. Tech., 14, 1253–1266,Short summary
Fast-response infrared gas sensors have been used over 3 decades for long-term monitoring of water vapor fluxes. As optically improved infrared gas sensors are newly employed, we evaluated the performance of water vapor density and water vapor flux from three generations of infrared gas sensors in Bushland, Texas, USA. From our experiments, fluxes from the old sensors were best representative of evapotranspiration based on a world-class lysimeter reference measurement.
Yuan You, Samar G. Moussa, Lucas Zhang, Long Fu, James Beck, and Ralf M. Staebler
Atmos. Meas. Tech., 14, 945–959,Short summary
Tailings ponds in the Alberta oil sands represent an insufficiently characterized source of fugitive emissions of pollutants to the atmosphere. In this study, a novel approach of using a Fourier transform infrared spectrometer along with measurements of atmospheric turbulence is shown to present a practical, non-intrusive method of quantifying emission rates for ammonia, alkanes, and methane. Results from a 1-month field study are presented and discussed.
Ravi Sahu, Ayush Nagal, Kuldeep Kumar Dixit, Harshavardhan Unnibhavi, Srikanth Mantravadi, Srijith Nair, Yogesh Simmhan, Brijesh Mishra, Rajesh Zele, Ronak Sutaria, Vidyanand Motiram Motghare, Purushottam Kar, and Sachchida Nand Tripathi
Atmos. Meas. Tech., 14, 37–52,Short summary
A unique feature of our low-cost sensor deployment is a swap-out experiment wherein four of the six sensors were relocated to different sites in the two phases. The swap-out experiment is crucial in investigating the efficacy of calibration models when applied to weather and air quality conditions vastly different from those present during calibration. We developed a novel local calibration algorithm based on metric learning that offers stable and accurate calibration performance.
Michal Vojtisek-Lom, Alessandro A. Zardini, Martin Pechout, Lubos Dittrich, Fausto Forni, François Montigny, Massimo Carriero, Barouch Giechaskiel, and Giorgio Martini
Atmos. Meas. Tech., 13, 5827–5843,Short summary
The feasibility of monitoring on-road emissions from small motorcycles with two highly compact portable emissions monitoring systems was evaluated on three motorcycles, with positive results. Mass emissions measured on the road were consistent among repeated runs, with differences between laboratory and on-road tests much larger than those between portable and laboratory systems, which were, on the average, within units of percent over standard test cycles.
Xiaoyu Sun, Minzheng Duan, Yang Gao, Rui Han, Denghui Ji, Wenxing Zhang, Nong Chen, Xiangao Xia, Hailei Liu, and Yanfeng Huo
Atmos. Meas. Tech., 13, 3595–3607,Short summary
The accurate measurement of greenhouse gases and their vertical distribution in the atmosphere is significant to the study of climate change and satellite remote sensing. Carbon dioxide and methane between 0.6 and 7 km were measured by the aircraft King Air 350ER in Jiansanjiang, northeast China, on 7–11 August 2018. The profiles show strong variation with the altitude and time, so the vertical structure of gases should be taken into account in the current satellite retrieval algorithm.
Christian Juncher Jørgensen, Jacob Mønster, Karsten Fuglsang, and Jesper Riis Christiansen
Atmos. Meas. Tech., 13, 3319–3328,Short summary
Recent discoveries have shown large emissions of methane (CH4) to the atmosphere from meltwater at the Greenland ice sheet (GrIS). Low-cost and low-power gas sensor technology offers great potential to supplement CH4 measurements using very expensive reference analyzers under harsh and remote conditions. In this paper we evaluate the in situ performance at the GrIS of a low-cost CH4 sensor to a state-of-the-art analyzer and find very excellent agreement between the two methods.
Lilian Joly, Olivier Coopmann, Vincent Guidard, Thomas Decarpenterie, Nicolas Dumelié, Julien Cousin, Jérémie Burgalat, Nicolas Chauvin, Grégory Albora, Rabih Maamary, Zineb Miftah El Khair, Diane Tzanos, Joël Barrié, Éric Moulin, Patrick Aressy, and Anne Belleudy
Atmos. Meas. Tech., 13, 3099–3118,Short summary
This article presents an instrument weighing less than 3 kg for accurate and rapid measurement of greenhouse gases between 0 and 30 km altitude using a meteorological balloon. This article shows the interest of these measurements for the validation of simulations of infrared satellite observations.
Jonathan Elsey, Marc D. Coleman, Tom D. Gardiner, Kaah P. Menang, and Keith P. Shine
Atmos. Meas. Tech., 13, 2335–2361,Short summary
Water vapour is an important component in trying to understand the flows of energy between the Sun and Earth, since it is opaque to radiation emitted by both the surface and the Sun. In this paper, we study how it absorbs sunlight by way of its
continuum, a property which is poorly understood and with few measurements. Our results indicate that this continuum absorption may be more significant than previously thought, potentially impacting satellite observations and climate studies.
Claudia Grossi, Scott D. Chambers, Olivier Llido, Felix R. Vogel, Victor Kazan, Alessandro Capuana, Sylvester Werczynski, Roger Curcoll, Marc Delmotte, Arturo Vargas, Josep-Anton Morguí, Ingeborg Levin, and Michel Ramonet
Atmos. Meas. Tech., 13, 2241–2255,Short summary
The sustainable support of radon metrology at the environmental level offers new scientific possibilities for the quantification of greenhouse gas (GHG) emissions and the determination of their source terms as well as for the identification of radioactive sources for the assessment of radiation exposure. This study helps to harmonize the techniques commonly used for atmospheric radon and radon progeny activity concentration measurements.
Cheng-Hsien Lin, Richard H. Grant, Albert J. Heber, and Cliff T. Johnston
Atmos. Meas. Tech., 13, 2001–2013,Short summary
Gas quantification using the open-path Fourier transform infrared spectrometer (OP-FTIR) is subject to interferences of environmental variables, leading to errors in gas concentration calculations. This study investigated the effects of ambient water vapour content, temperature, path lengths, and wind speed on the quantification of N2O and CO2 concentrations, which can help the OP-FTIR users to avoid these errors and improve the precision and accuracy of the atmospheric gas quantification.
Rachel Edie, Anna M. Robertson, Robert A. Field, Jeffrey Soltis, Dustin A. Snare, Daniel Zimmerle, Clay S. Bell, Timothy L. Vaughn, and Shane M. Murphy
Atmos. Meas. Tech., 13, 341–353,Short summary
Ground-based measurements of emissions from oil and natural gas production are important for understanding emission distributions and improving emission inventories. Here, measurement technique Other Test Method 33A (OTM 33A) is validated through several test releases staged at the Methane Emissions Technology Evaluation Center. These tests suggest OTM 33A has no inherent bias and that a group of OTM measurements is within 5 % of the known mean emission rate.
Zheng Xu, Yuliang Liu, Wei Nie, Peng Sun, Xuguang Chi, and Aijun Ding
Atmos. Meas. Tech., 12, 6737–6748,Short summary
We evaluated the performance of HONO measurement by a wet-denuder--ion0chromatography system (WD/IC, MARGA). We found significant artificial HONO formed from the reaction of NO2 oxidizing SO2 in the denuder solution. High ambient NH3 would elevate the pH of the denuder solution and promote the overestimation of HONO. A method was established to correct the HONO measurement by WD/IC instruments.
Leigh R. Crilley, Louisa J. Kramer, Bin Ouyang, Jun Duan, Wenqian Zhang, Shengrui Tong, Maofa Ge, Ke Tang, Min Qin, Pinhua Xie, Marvin D. Shaw, Alastair C. Lewis, Archit Mehra, Thomas J. Bannan, Stephen D. Worrall, Michael Priestley, Asan Bacak, Hugh Coe, James Allan, Carl J. Percival, Olalekan A. M. Popoola, Roderic L. Jones, and William J. Bloss
Atmos. Meas. Tech., 12, 6449–6463,Short summary
Nitrous acid (HONO) is key species for understanding tropospheric chemistry, yet accurate and precise measurements are challenging. Here we report an inter–comparison exercise of a number of instruments that measured HONO in a highly polluted location (Beijing). All instruments agreed on the temporal trends yet displayed divergence in absolute concentrations. The cause of this divergence was unclear, but it may in part be due to spatial variability in instrument location.
Rupert Holzinger, W. Joe F. Acton, William J. Bloss, Martin Breitenlechner, Leigh R. Crilley, Sébastien Dusanter, Marc Gonin, Valerie Gros, Frank N. Keutsch, Astrid Kiendler-Scharr, Louisa J. Kramer, Jordan E. Krechmer, Baptiste Languille, Nadine Locoge, Felipe Lopez-Hilfiker, Dušan Materić, Sergi Moreno, Eiko Nemitz, Lauriane L. J. Quéléver, Roland Sarda Esteve, Stéphane Sauvage, Simon Schallhart, Roberto Sommariva, Ralf Tillmann, Sergej Wedel, David R. Worton, Kangming Xu, and Alexander Zaytsev
Atmos. Meas. Tech., 12, 6193–6208,
Christoph Zellweger, Rainer Steinbrecher, Olivier Laurent, Haeyoung Lee, Sumin Kim, Lukas Emmenegger, Martin Steinbacher, and Brigitte Buchmann
Atmos. Meas. Tech., 12, 5863–5878,Short summary
We analysed results obtained through CO and N2O performance audits conducted within the framework of the Global Atmosphere Watch (GAW) quality management system of the World Meteorology Organization (WMO). The results reveal that current spectroscopic measurement techniques have clear advantages with respect to data quality objectives compared to more traditional methods. Further, they allow for a smooth continuation of historic CO and N2O time series.
Lukas Siebicke and Anas Emad
Atmos. Meas. Tech., 12, 4393–4420,Short summary
We present the emerging flux measurement method
true eddy accumulation(TEA), able to quantify the land–atmosphere exchange of a large number of trace gases which are important for air quality and atmospheric composition. Our innovative implementation provides proof of concept of TEA and compared well to the established reference, outperforming previous works on TEA. Key to the success was the innovative high-speed air sampling and fully digital real-time data processing system.
Loic Lechevallier, Roberto Grilli, Erik Kerstel, Daniele Romanini, and Jérôme Chappellaz
Atmos. Meas. Tech., 12, 3101–3109,Short summary
In this work we describe a highly sensitive optical spectrometer for simultaneous measurement of methane, ethane, and the isotopic composition of methane. The coupling of the spectrometer with a dissolved gas extraction system will provide a suitable tool for understanding the origins of the dissolved hydrocarbons and discriminate between the different sources (e.g., biogenic vs. thermogenic).
Kate R. Smith, Peter M. Edwards, Peter D. Ivatt, James D. Lee, Freya Squires, Chengliang Dai, Richard E. Peltier, Mat J. Evans, Yele Sun, and Alastair C. Lewis
Atmos. Meas. Tech., 12, 1325–1336,Short summary
Clusters of low-cost, low-power atmospheric gas sensors were built into a sensor instrument to monitor NO2 and O3 in Beijing, alongside reference instruments, aiming to improve the reliability of sensor measurements. Clustering identical sensors and using the median sensor signal was used to minimize drift over short and medium timescales. Three different machine learning techniques were used for all the sensor data in an attempt to correct for cross-interferences, which worked to some degree.
Mei Bai, Helen Suter, Shu Kee Lam, Thomas K. Flesch, and Deli Chen
Atmos. Meas. Tech., 12, 1095–1102,Short summary
Improving direct field measurement techniques to quantify gas emissions from large agriculture farm is challenging. We measured nitrous oxide (N2O) emissions with static closed chambers and slant open-path flux gradient (FG) approaches following chicken manure application. The concurrent emission ratios (FG / chamber) showed N2O fluxes measured by FG were 1.22-1.40 times higher than those from the chambers. This study provides important information for the agriculture gas measurement community.
Vincent Michoud, Stéphane Sauvage, Thierry Léonardis, Isabelle Fronval, Alexandre Kukui, Nadine Locoge, and Sébastien Dusanter
Atmos. Meas. Tech., 11, 5729–5740,Short summary
This study presents the first measurements of ambient methylglyoxal, an important atmospheric α-dicarbonyl, using proton transfer reaction time-of-flight mass spectrometry. These measurements mostly agree with concomitant measurements from a reference technique: the DNPH derivatization technique and high-performance liquid chromatography with UV detection. In addition, a careful investigation of the differences between the two techniques is carried out to explain the disagreements observed.
Michael J. Prather, Clare M. Flynn, Xin Zhu, Stephen D. Steenrod, Sarah A. Strode, Arlene M. Fiore, Gustavo Correa, Lee T. Murray, and Jean-Francois Lamarque
Atmos. Meas. Tech., 11, 2653–2668,Short summary
A new protocol for merging in situ atmospheric chemistry measurements with 3-D models is developed. This technique can identify the most reactive air parcels in terms of tropospheric production/loss of O3 & CH4. This approach highlights differences in 6 global chemistry models even with composition specified. Thus in situ measurements from, e.g., NASA's ATom mission can be used to develop a chemical climatology of, not only the key species, but also the rates of key reactions in each air parcel.
Richard H. Grant and Rex A. Omonode
Atmos. Meas. Tech., 11, 2119–2133,Short summary
Annual emissions of trace gases requires knowledge of the emissions throughout the day and year. Unfortunately emissions into the surface boundary layer during calm nights are rarely measured. During such conditions surface layer concentrations of carbon dioxide (CO2) and nitrous oxide (N2O) often accumulate in the surface boundary layer and the time rate of change of this accumulation was used to estimate emissions. Results showed this approach to be reasonable.
Kira Sadighi, Evan Coffey, Andrea Polidori, Brandon Feenstra, Qin Lv, Daven K. Henze, and Michael Hannigan
Atmos. Meas. Tech., 11, 1777–1792,Short summary
Ground-level ozone has negative human health impacts. In the summer of 2015, 13 low-cost sensor monitors were deployed to several neighborhoods around Riverside, California. There were significant spatial differences between monitors. This is important because it means that ozone in certain places may be higher than what EPA monitors report for an area, which is pertinent for residents of those communities. This research helps inform the limitations and advantages of low-cost sensor networks.
Bas Mijling, Qijun Jiang, Dave de Jonge, and Stefano Bocconi
Atmos. Meas. Tech., 11, 1297–1312,Short summary
Although in many cities the population is exposed to air pollution, real-time air quality is usually only measured at a few locations. New low-cost sensor technology has the potential to extend the monitoring network significantly. We show that citizen science campaigns using the current generations of electrochemical NO2 sensors may provide useful complementary data on local air quality in an urban setting, provided that experiments are properly set up and the data are carefully analysed.
Natasha L. Miles, Douglas K. Martins, Scott J. Richardson, Christopher W. Rella, Caleb Arata, Thomas Lauvaux, Kenneth J. Davis, Zachary R. Barkley, Kathryn McKain, and Colm Sweeney
Atmos. Meas. Tech., 11, 1273–1295,Short summary
Analyzers measuring methane and methane isotopic ratio were deployed at four towers in the Marcellus Shale natural gas extraction region of Pennsylvania. The methane isotopic ratio is helpful for differentiating emissions from natural gas activities from other sources (e.g., landfills). We describe the analyzer calibration. The signals observed in the study region were generally small, but the instrumental performance demonstrated here could be used in regions with stronger enhancements.
David H. Hagan, Gabriel Isaacman-VanWertz, Jonathan P. Franklin, Lisa M. M. Wallace, Benjamin D. Kocar, Colette L. Heald, and Jesse H. Kroll
Atmos. Meas. Tech., 11, 315–328,Short summary
The use of low-cost sensors for air pollution research has outpaced our understanding of their capabilities and limitations under real-world conditions. Here we describe the deployment, calibration and evaluation of electrochemical sensors on the Island of Hawai‘i. We obtain excellent performance (RMSE < 7 ppb, r2 = 0.997) across a wide dynamic range (1 ppb–2 ppm). We introduce a hybrid regression algorithm which works across a large dynamic range and shows little decay in sensitivity over time.
Erin Dunne, Ian E. Galbally, Min Cheng, Paul Selleck, Suzie B. Molloy, and Sarah J. Lawson
Atmos. Meas. Tech., 11, 141–159,Short summary
A comparison of measurements of 7 volatile organic compounds (VOCs) in urban air by 3 different methods is presented. An uncertainty was calculated for each method and VOCs measured to provide some idea of the reliability of the data. Even when this uncertainty was accounted for, the measurements from the different methods did not agree for 4 of the 7 VOCs. Thus, there is unaccounted uncertainty in VOC measurements which must be considered when utilizing the data and assessing their reliability.
Michelle M. Lew, Sebastien Dusanter, and Philip S. Stevens
Atmos. Meas. Tech., 11, 95–109,Short summary
This paper describes measurements of the conversion efficiency of several organic peroxy radicals upon reaction with nitric oxide to the hydroperoxy radical, which can interfere with measurements of the latter. This interference could explain some of the discrepancies between measurements and model predictions of the hydroperoxy radical. Previous measurements of the hydroperoxy radical during the Mexico City Metropolitan Area campaign in 2006 are reanalyzed to account for the interference.
Pamela Rickly and Philip S. Stevens
Atmos. Meas. Tech., 11, 1–16,Short summary
The hydroxyl radical is the primary atmospheric oxidant in the atmosphere, and measurements of its concentration provide a rigorous test of our understanding of atmospheric chemistry. This paper presents measurements of a potential interference with measurements of OH using laser-induced fluorescence techniques, which may contribute to measurements of OH in forested environments. The results may help to explain discrepancies between measurements and model predictions in these environments.
Sébastien Ars, Grégoire Broquet, Camille Yver Kwok, Yelva Roustan, Lin Wu, Emmanuel Arzoumanian, and Philippe Bousquet
Atmos. Meas. Tech., 10, 5017–5037,Short summary
This study presents a new concept for estimating the pollutant emission rates of a site combining the tracer release method, local-scale atmospheric transport modelling and a statistical atmospheric inversion approach. The potential of this new concept is evaluated with a practical implementation based on a series of inversions of controlled methane and tracer point sources in different spatial configurations to assess the efficiency of the method in comparison with the classic tracer method.
Hendrik Fuchs, Anna Novelli, Michael Rolletter, Andreas Hofzumahaus, Eva Y. Pfannerstill, Stephan Kessel, Achim Edtbauer, Jonathan Williams, Vincent Michoud, Sebastien Dusanter, Nadine Locoge, Nora Zannoni, Valerie Gros, Francois Truong, Roland Sarda-Esteve, Danny R. Cryer, Charlotte A. Brumby, Lisa K. Whalley, Daniel Stone, Paul W. Seakins, Dwayne E. Heard, Coralie Schoemaecker, Marion Blocquet, Sebastien Coudert, Sebastien Batut, Christa Fittschen, Alexander B. Thames, William H. Brune, Cheryl Ernest, Hartwig Harder, Jennifer B. A. Muller, Thomas Elste, Dagmar Kubistin, Stefanie Andres, Birger Bohn, Thorsten Hohaus, Frank Holland, Xin Li, Franz Rohrer, Astrid Kiendler-Scharr, Ralf Tillmann, Robert Wegener, Zhujun Yu, Qi Zou, and Andreas Wahner
Atmos. Meas. Tech., 10, 4023–4053,Short summary
Hydroxyl radical reactivity (k(OH)) is closely related to processes that lead to the formation of oxidised, secondary pollutants such as ozone and aerosol. In order to compare the performances of instruments measuring k(OH), experiments were conducted in the simulation chamber SAPHIR. Chemical conditions were chosen either to be representative of the atmosphere or to test potential limitations of instruments. Overall, the results show that instruments are capable of measuring k(OH).
Eben S. Cross, Leah R. Williams, David K. Lewis, Gregory R. Magoon, Timothy B. Onasch, Michael L. Kaminsky, Douglas R. Worsnop, and John T. Jayne
Atmos. Meas. Tech., 10, 3575–3588,Short summary
Low-cost air quality sensor technologies offer new opportunities for fast and distributed measurements of air pollution, but a persistent characterization gap remains when it comes to evaluating sensor performance under realistic environmental sampling conditions. We present results from a newly developed integrated AQ-sensor system (ARISense) and demonstrate the utility of using high-dimensional model representation to improve the conversion of raw sensor signal to ambient concentration.
Abigail Koss, Bin Yuan, Carsten Warneke, Jessica B. Gilman, Brian M. Lerner, Patrick R. Veres, Jeff Peischl, Scott Eilerman, Rob Wild, Steven S. Brown, Chelsea R. Thompson, Thomas Ryerson, Thomas Hanisco, Glenn M. Wolfe, Jason M. St. Clair, Mitchell Thayer, Frank N. Keutsch, Shane Murphy, and Joost de Gouw
Atmos. Meas. Tech., 10, 2941–2968,Short summary
Oil and gas extraction activity can cause air quality issues through emission of reactive chemicals. VOCs related to extraction operations in the United States were measured by PTR-ToF-MS from aircraft during the SONGNEX campaign in March–April 2015. The detailed analysis in this work provides a guide to interpreting PTR-ToF measurements in oil- and gas-producing regions, and it includes fundamental observations of VOC speciation and mixing ratios.
Caroline Brosy, Karina Krampf, Matthias Zeeman, Benjamin Wolf, Wolfgang Junkermann, Klaus Schäfer, Stefan Emeis, and Harald Kunstmann
Atmos. Meas. Tech., 10, 2773–2784,Short summary
Vertical and horizontal sounding of the planetary boundary layer can be complemented by unmanned aerial vehicles (UAV). Utilizing a multicopter-type UAV spatial sampling of air and simultaneously sensing of meteorological variables is possible for the study of surface exchange processes. During stable atmospheric conditions, vertical methane gradients of about 300 ppb were found. This approach extended the vertical profile height of existing tower-based infrastructure by a factor of five.
Cory R. Martin, Ning Zeng, Anna Karion, Russell R. Dickerson, Xinrong Ren, Bari N. Turpie, and Kristy J. Weber
Atmos. Meas. Tech., 10, 2383–2395,Short summary
A low-cost sensor for measuring carbon dioxide is evaluated for its performance in detecting concentrations in Earth's atmosphere. After a multivariate regression correcting for environmental variables, the root mean square error between it and a research-grade gas analyzer is less than 0.5 % of the observed average value. This demonstrates the viability for using these sensors in certain real-world atmospheric observing applications.
Lukas Lesmeister and Matthias Koschorreck
Atmos. Meas. Tech., 10, 2377–2382,Short summary
Greenhouse gas emissions from dry aquatic sediments are probably globally relevant. However, they are difficult to measure because of the often rocky substrate. We tested the performance of different materials to seal a closed chamber to stony ground both in laboratory and field experiments. Pottery clay was a convenient sealing material, while the use of on-site material produced artefacts. We confirmed that CO2 fluxes from dry aquatic sediments were similar to fluxes from
Terry Deshler, Rene Stübi, Francis J. Schmidlin, Jennifer L. Mercer, Herman G. J. Smit, Bryan J. Johnson, Rigel Kivi, and Bruno Nardi
Atmos. Meas. Tech., 10, 2021–2043,Short summary
Ozonesondes, small balloon-borne instruments to measure ozone profiles, are used once and lost. Quality control is thus essential. From the mid-1990s to late 2000s differences in manufacturers' (Science Pump and ENSCI) recommended sensor solution concentrations, 1.0 % and 0.5 % potassium iodide, led to some confusion. This paper uses comparison measurements to derive transfer functions to homogenize the measurements made with non-standard combinations of instrument and sensor solution.
Irène Ventrillard, Irène Xueref-Remy, Martina Schmidt, Camille Yver Kwok, Xavier Faïn, and Daniele Romanini
Atmos. Meas. Tech., 10, 1803–1812,Short summary
We present a comparison of CO measurements performed with a portable OF-CEAS laser spectrometer against a high-performance gas chromatograph. For both surface and airborne measurements, the instruments show an excellent agreement very close to the 2 ppb World Meteorological Organization recommendation for CO inter-laboratory comparison. This work establishes that this laser technique allows for the development of sensitive, compact, robust and reliable instruments for in situ trace-gas analysis.
Dominik Schmithüsen, Scott Chambers, Bernd Fischer, Stefan Gilge, Juha Hatakka, Victor Kazan, Rolf Neubert, Jussi Paatero, Michel Ramonet, Clemens Schlosser, Sabine Schmid, Alex Vermeulen, and Ingeborg Levin
Atmos. Meas. Tech., 10, 1299–1312,Short summary
A European-wide 222radon/222radon progeny comparison study has been conducted at nine measurement stations in order to determine differences between existing 222radon instrumentation and atmospheric data sets, respectively. Mean differences up to 45 % were found between monitors. These differences need to be taken into account if the data shall serve for quantitative regional atmospheric transport model validation.
Jingyong Ma, Tianshan Zha, Xin Jia, Steve Sargent, Rex Burgon, Charles P.-A. Bourque, Xinhua Zhou, Peng Liu, Yujie Bai, and Yajuan Wu
Atmos. Meas. Tech., 10, 1259–1267,Short summary
The vortex intake significantly reduced maintenance requirements and downtime for a closed-path eddy-covariance system compared to the original inline filter design. Vortex intake kept the sample cell windows cleaner, preserving the optical signal strength of CO2 longer. Its installation also avoided the need for an inline filter in the sample path, sustaining an acceptable sample cell differential pressure over a much longer period. There was no significant attenuation of high frequencies.
Carsten Schaller, Mathias Göckede, and Thomas Foken
Atmos. Meas. Tech., 10, 869–880,Short summary
The eddy covariance (EC) method allows for measuring and calculating vertical turbulent exchange fluxes between ecosystems and the atmosphere. It fails in non-steady-state flow conditions, e.g. in Arctic regions. Two alternative calculation methods, conditional sampling and wavelet analysis, were implemented and compared to EC. Wavelet analysis for allows calculating a trustworthy flux even in non-stationary times and offers new possibilities for exact flux calculation in difficult environments.
Heidi Hellén, Simon Schallhart, Arnaud P. Praplan, Tuukka Petäjä, and Hannele Hakola
Atmos. Meas. Tech., 10, 281–289,Short summary
There is a lack of knowledge of volatile organic acids (VOAs), other than formic and acetic acids in gas phase, and this is at least partly due to the lack of sensitive enough measurement methods. In the present study we developed an in situ GC–MS measurement method for measuring C2–C7 monocarboxylic VOAs at ambient air concentration levels, which we used to measure ambient air concentrations in a boreal forest site. In addition, found mixing ratios were compared with PTR-TOFMS data.
Long Cui, Zhou Zhang, Yu Huang, Shun Cheng Lee, Donald Ray Blake, Kin Fai Ho, Bei Wang, Yuan Gao, Xin Ming Wang, and Peter Kwok Keung Louie
Atmos. Meas. Tech., 9, 5763–5779,Short summary
In this manuscript, the effect of ambient RH and T on HCHO measurements by PTR-MS was investigated, and the Poly 2-D regression was found to be a good nonlinear surface simulation of R (RH, T) for correcting measured HCHO concentration. Intercomparisons between PTR-MS and other OVOC and VOC measuring techniques were conducted through a field study in urban roadside areas of Hong Kong primarily, and good agreements were found between these different techniques.
Mingxi Yang, John Prytherch, Elena Kozlova, Margaret J. Yelland, Deepulal Parenkat Mony, and Thomas G. Bell
Atmos. Meas. Tech., 9, 5509–5522,Short summary
The exchange of the greenhouse gases carbon dioxide and methane between the ocean and the atmosphere is of critical importance for the earth's climate. Despite this, direct measurements of these fluxes are relatively scarce, especially for methane, in large part due to instrumental challenges. In this paper, we evaluate the performance of two of the latest carbon dioxide and methane flux analysers. We also compare their detection limits to predicted air–sea fluxes of these gases.
Stephen J. Andrews, Lucy J. Carpenter, Eric C. Apel, Elliot Atlas, Valeria Donets, James R. Hopkins, Rebecca S. Hornbrook, Alastair C. Lewis, Richard T. Lidster, Richard Lueb, Jamie Minaeian, Maria Navarro, Shalini Punjabi, Daniel Riemer, and Sue Schauffler
Atmos. Meas. Tech., 9, 5213–5225,Short summary
We present a comparison of aircraft measurements of important trace gases from a co-ordinated campaign in Jan–Feb 2014 in the tropical west Pacific involving the NASA Global Hawk, NCAR GV and FAAM BAe-146 aircraft. The paper studies the comparability of separate measurements across platforms and demonstrates that aircraft measurements are relevant for characterising the vertical uplift of important gases, such as those with ozone-depleting potential, to the upper troposphere–lower stratosphere.
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Analyzing street-level air pollutants (2016–2017), this assessment indicates that mobile measurement is precise and accurate (5 % to 25 % bias) relative to regulatory sites, with higher spatial resolution. Collocated sensor measurements in California showed differences less than 20 %, suggesting that greater differences represent spatial variability. Mobile data confirm regulatory-site spatial representation and that pollutant levels can also be 6 to 8 times higher just blocks apart.
Analyzing street-level air pollutants (2016–2017), this assessment indicates that mobile...