Articles | Volume 12, issue 6
https://doi.org/10.5194/amt-12-3351-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-12-3351-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
26 Jun 2019
Research article |
| 26 Jun 2019
| 26 Jun 2019
A novel approach to calibrating a photoacoustic absorption spectrometer using polydisperse absorbing aerosol
Katie Foster
Atmospheric Science, University of Wyoming, Laramie, WY 82071, USA
Rudra Pokhrel
Atmospheric Science, University of Wyoming, Laramie, WY 82071, USA
Matthew Burkhart
Atmospheric Science, University of Wyoming, Laramie, WY 82071, USA
Shane Murphy
CORRESPONDING AUTHOR
Atmospheric Science, University of Wyoming, Laramie, WY 82071, USA
Related authors
No articles found.
Yingjie Shen, Rudra P. Pokhrel, Amy P. Sullivan, Ezra J. T. Levin, Lauren A. Garofalo, Delphine K. Farmer, Wade Permar, Lu Hu, Darin W. Toohey, Teresa Campos, Emily V. Fischer, and Shane M. Murphy
Atmos. Chem. Phys., 24, 12881–12901, https://doi.org/10.5194/acp-24-12881-2024, https://doi.org/10.5194/acp-24-12881-2024, 2024
Short summary
Short summary
The magnitude and evolution of brown carbon (BrC) absorption remain unclear, with uncertainty in climate models. Data from the WE-CAN airborne experiment show that model parameterizations overestimate the mass absorption cross section (MAC) of BrC. Observed decreases in BrC absorption with chemical markers are due to decreasing organic aerosol (OA) mass rather than a decreasing BrC MAC, which is currently implemented in models. Water-soluble BrC contributes 23 % of total absorption at 660 nm.
Shelby Fuller, Samuel A. Marlow, Samuel Haimov, Matthew Burkhart, Kevin Shaffer, Austin Morgan, and Jefferson R. Snider
Atmos. Meas. Tech., 16, 6123–6142, https://doi.org/10.5194/amt-16-6123-2023, https://doi.org/10.5194/amt-16-6123-2023, 2023
Short summary
Short summary
Snowfall rate and radar reflectivity measurements were analyzed. We confirmed that the relationship between snowfall rate and reflectivity is dependent on snow particle type. It is likely that the measured snowfall was produced by solid (ice) particles colliding with liquid cloud droplets, forming rimed snow particles. This analysis is expected to improve snowfall rate estimation based on measurements made using W-band radars.
Shreta Ghimire, Zachary J. Lebo, Shane Murphy, Stefan Rahimi, and Trang Tran
Atmos. Chem. Phys., 23, 9413–9438, https://doi.org/10.5194/acp-23-9413-2023, https://doi.org/10.5194/acp-23-9413-2023, 2023
Short summary
Short summary
High wintertime ozone levels have occurred often in recent years in mountain basins with oil and gas production facilities. Photochemical modeling of ozone production serves as a basis for understanding the mechanism by which it occurs and for predictive capability. We present photochemical model simulations of ozone formation and accumulation in the Upper Green River basin, Wyoming, demonstrating the model's ability to simulate wintertime ozone and the sensitivity of ozone to its precursors.
Amy P. Sullivan, Rudra P. Pokhrel, Yingjie Shen, Shane M. Murphy, Darin W. Toohey, Teresa Campos, Jakob Lindaas, Emily V. Fischer, and Jeffrey L. Collett Jr.
Atmos. Chem. Phys., 22, 13389–13406, https://doi.org/10.5194/acp-22-13389-2022, https://doi.org/10.5194/acp-22-13389-2022, 2022
Short summary
Short summary
During the WE-CAN (Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption and Nitrogen) study, brown carbon (BrC) absorption was measured on the NSF/NCAR C-130 aircraft using a particle-into-liquid sampler and photoacoustic aerosol absorption spectrometer. Approximately 45 % of the BrC absorption in wildfires was observed to be due to water-soluble species. The ratio of BrC absorption to WSOC or ΔCO showed no clear dependence on fire dynamics or the time since emission over 9 h.
Damon M. Smith, Marc N. Fiddler, Rudra P. Pokhrel, and Solomon Bililign
Atmos. Chem. Phys., 20, 10149–10168, https://doi.org/10.5194/acp-20-10149-2020, https://doi.org/10.5194/acp-20-10149-2020, 2020
Short summary
Short summary
Biomass burning aerosol can scatter and absorb light, contributing to the cooling or warming of the planet. The scattering and absorption properties (optical properties) change as aerosol ages and interacts with atmospheric gases. Optical properties also depend on burning conditions, fuel type, and morphology. Africa is a major source of biomass burning aerosols, but there are very few laboratory studies. This study focuses on the optical properties of aerosols from east African biomass fuels.
Damon M. Smith, Tianqu Cui, Marc N. Fiddler, Rudra P. Pokhrel, Jason D. Surratt, and Solomon Bililign
Atmos. Chem. Phys., 20, 10169–10191, https://doi.org/10.5194/acp-20-10169-2020, https://doi.org/10.5194/acp-20-10169-2020, 2020
Short summary
Short summary
Biomass fuels used for domestic purposes in east Africa produce a significant atmospheric burden of aerosols and volatile organic compounds. The chemical properties and composition of these aerosols have not been investigated in the laboratory. In this work methanol extracts from filter samples of aerosol collected from an indoor smog chamber were analyzed to determine the chemical composition and identify the light absorption properties of organic aerosol constituents.
Rachel Edie, Anna M. Robertson, Robert A. Field, Jeffrey Soltis, Dustin A. Snare, Daniel Zimmerle, Clay S. Bell, Timothy L. Vaughn, and Shane M. Murphy
Atmos. Meas. Tech., 13, 341–353, https://doi.org/10.5194/amt-13-341-2020, https://doi.org/10.5194/amt-13-341-2020, 2020
Short summary
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.
Hunter Brown, Xiaohong Liu, Yan Feng, Yiquan Jiang, Mingxuan Wu, Zheng Lu, Chenglai Wu, Shane Murphy, and Rudra Pokhrel
Atmos. Chem. Phys., 18, 17745–17768, https://doi.org/10.5194/acp-18-17745-2018, https://doi.org/10.5194/acp-18-17745-2018, 2018
Short summary
Short summary
In climate models, organic carbon (OC) in wildfire smoke has been treated as an atmospheric cooling component by reflecting sunlight back to space. This study incorporates the observationally identified absorbing brown carbon component of OC into the Community Earth System Model, improving the agreement between the model and observations and effectively increasing absorption of solar radiation. This change contributes to altered atmospheric dynamics and changes in cloud cover in the model.
Nicholas Zelasko, Adam Wettlaufer, Bujidmaa Borkhuu, Matthew Burkhart, Leah S. Campbell, W. James Steenburgh, and Jefferson R. Snider
Atmos. Meas. Tech., 11, 441–458, https://doi.org/10.5194/amt-11-441-2018, https://doi.org/10.5194/amt-11-441-2018, 2018
Short summary
Short summary
The hotplate precipitation gauge has the potential to solve some problems with conventional precipitation gauge measurements, especially for snowfall. This paper extends the seminal published work, Rasmussen et al. (2011). We assert that the precipitation rate algorithm we have developed for the hotplate is an improvement on that which was previously published.
Rudra P. Pokhrel, Eric R. Beamesderfer, Nick L. Wagner, Justin M. Langridge, Daniel A. Lack, Thilina Jayarathne, Elizabeth A. Stone, Chelsea E. Stockwell, Robert J. Yokelson, and Shane M. Murphy
Atmos. Chem. Phys., 17, 5063–5078, https://doi.org/10.5194/acp-17-5063-2017, https://doi.org/10.5194/acp-17-5063-2017, 2017
Short summary
Short summary
This study investigates enhancement of black carbon (BC) absorption in biomass burning emissions due to absorbing and non-absorbing coatings. The fraction of absorption due to BC, brown carbon (BrC), and lensing is estimated using different approaches. The similarities and differences between the results from these approaches are discussed. Absorption by BrC is shown to have good correlation with the elemental to organic carbon ratio (EC / OC) and AAE.
Rudra P. Pokhrel, Nick L. Wagner, Justin M. Langridge, Daniel A. Lack, Thilina Jayarathne, Elizabeth A. Stone, Chelsea E. Stockwell, Robert J. Yokelson, and Shane M. Murphy
Atmos. Chem. Phys., 16, 9549–9561, https://doi.org/10.5194/acp-16-9549-2016, https://doi.org/10.5194/acp-16-9549-2016, 2016
Short summary
Short summary
This paper gives first multi-wavelength estimates of SSA and AAE of emissions from combustion of Indonesian peat. In addition, it demonstrates that SSA of biomass burning emissions can be parameterized with EC / (EC+OC) and that this parameterization is quantitatively superior to previously published parameterizations based on MCE. It also shows that EC / (EC+OC) parameterization accurately predicts SSA during the first few hours of aging of a biomass burning plume.
R. A. Field, J. Soltis, M. C. McCarthy, S. Murphy, and D. C. Montague
Atmos. Chem. Phys., 15, 3527–3542, https://doi.org/10.5194/acp-15-3527-2015, https://doi.org/10.5194/acp-15-3527-2015, 2015
Short summary
Short summary
Emissions from oil and natural gas development in the Upper Green River basin of Wyoming are known to drive wintertime ozone production. Fugitive emissions of natural gas and condensate provide sufficient non-methane hydrocarbons (NMHC) to promote episodic ozone formation. A water treatment and recycling facility was identified as a significant source of NMHC, including toluene and m+p-xylene. Emissions from this facility have a strong influence upon peak ozone measured at downwind sites.
C. Warneke, P. Veres, S. M. Murphy, J. Soltis, R. A. Field, M. G. Graus, A. Koss, S.-M. Li, R. Li, B. Yuan, J. M. Roberts, and J. A. de Gouw
Atmos. Meas. Tech., 8, 411–420, https://doi.org/10.5194/amt-8-411-2015, https://doi.org/10.5194/amt-8-411-2015, 2015
Related subject area
Subject: Aerosols | Technique: In Situ Measurement | Topic: Instruments and Platforms
A solid-state infrared laser for two-step desorption–ionization processes in single-particle mass spectrometry
CIAO main upgrade: building up an ACTRIS-compliant aerosol in situ laboratory
STRAS: a new high-time-resolution aerosol sampler for particle-induced X-ray emission (PIXE) analysis
The Flying Laboratory FLab: development and application of a UAS to measure aerosol particles and trace gases in the lower troposphere
The T-Bird – A new aircraft-towed instrument platform to measure turbulence and aerosol properties close to the surface: Introduction to the aerosol measurement system
Fast and sensitive measurements of sub-3 nm particles using Condensation Particle Counters For Atmospheric Rapid Measurements (CPC FARM)
Performance evaluation of an online monitor based on X-ray fluorescence for detecting elemental concentrations in ambient particulate matter
Deriving the hygroscopicity of ambient particles using low-cost optical particle counters
In-situ volcanic ash sampling and aerosol-gas analysis based on UAS technologies (AeroVolc)
A novel aerosol filter sampler for measuring the vertical distribution of ice-nucleating particles via fixed-wing uncrewed aerial vehicles
Simulations of the collection of mesospheric dust particles with a rocket instrument
Characterisation of particle single-scattering albedo with a modified airborne dual-wavelength CAPS monitor
Use of an uncrewed aerial system to investigate aerosol direct and indirect radiative forcing effects in the marine atmosphere
Characterization of the airborne aerosol inlet and transport system used during the A-LIFE aircraft field experiment
Large-scale automated emission measurement of individual vehicles with point sampling
Development of a cascade impactor optimized for size-fractionated analysis of aerosol metal content by total reflection X-ray fluorescence spectroscopy (TXRF)
Modular Multiplatform Compatible Air Measurement System (MoMuCAMS): a new modular platform for boundary layer aerosol and trace gas vertical measurements in extreme environments
Two new multirotor uncrewed aerial vehicles (UAVs) for glaciogenic cloud seeding and aerosol measurements within the CLOUDLAB project
Real-time pollen identification using holographic imaging and fluorescence measurements
Assessing potential indicators of aerosol wet scavenging during long-range transport
Next-generation ice-nucleating particle sampling on board aircraft: characterization of the High-volume flow aERosol particle filter sAmpler (HERA)
Development and characterization of the Portable Ice Nucleation Chamber 2 (PINCii)
The four-wavelength Photoacoustic Aerosol Absorption Spectrometer (PAAS-4λ)
Improved counting statistics of an ultrafine differential mobility particle size spectrometer system
Performance evaluation of the Alphasense OPC-N3 and Plantower PMS5003 sensor in measuring dust events in the Salt Lake Valley, Utah
Source apportionment of black carbon and combustion-related CO2 for the determination of source-specific emission factors
CAMP: an instrumented platform for balloon-borne aerosol particle studies in the lower atmosphere
New method to determine black carbon mass size distribution
The realization of autonomous, aircraft-based, real-time aerosol mass spectrometry in the upper troposphere and lower stratosphere
A study on the performance of low-cost sensors for source apportionment at an urban background site
A dual-wavelength photothermal aerosol absorption monitor: design, calibration and performance
A high-transmission axial ion mobility classifier for mass–mobility measurements of atmospheric ions
Design, characterization, and first field deployment of a novel aircraft-based aerosol mass spectrometer combining the laser ablation and flash vaporization techniques
An instrument for direct measurement of emissions: cooling tower example
The Aerosol Research Observation Station (AEROS)
Laser imaging nephelometer for aircraft deployment
A new method to quantify particulate sodium and potassium salts (nitrate, chloride, and sulfate) by thermal desorption aerosol mass spectrometry
Evaluating the PurpleAir monitor as an aerosol light scattering instrument
Undersizing of aged African biomass burning aerosol by an ultra-high-sensitivity aerosol spectrometer
Evaluation methods for low-cost particulate matter sensors
Simulation-aided characterization of a versatile water-based condensation particle counter for atmospheric airborne research
Development of an in situ dual-channel thermal desorption gas chromatography instrument for consistent quantification of volatile, intermediate-volatility and semivolatile organic compounds
Assessment of online water-soluble brown carbon measuring systems for aircraft sampling
Characterizing the performance of a POPS miniaturized optical particle counter when operated on a quadcopter drone
A low-cost monitor for simultaneous measurement of fine particulate matter and aerosol optical depth – Part 3: Automation and design improvements
Rapid measurement of RH-dependent aerosol hygroscopic growth using a humidity-controlled fast integrated mobility spectrometer (HFIMS)
Detection of ship plumes from residual fuel operation in emission control areas using single-particle mass spectrometry
Highly time-resolved characterization of carbonaceous aerosols using a two-wavelength Sunset thermal–optical carbon analyzer
Captive Aerosol Growth and Evolution (CAGE) chamber system to investigate particle growth due to secondary aerosol formation
Design and characterization of a new oxidation flow reactor for laboratory and long-term ambient studies
Marco Schmidt, Haseeb Hakkim, Lukas Anders, Aleksandrs Kalamašņikovs, Thomas Kröger-Badge, Robert Irsig, Norbert Graf, Reinhard Kelnberger, Johannes Passig, and Ralf Zimmermann
Atmos. Meas. Tech., 18, 2425–2437, https://doi.org/10.5194/amt-18-2425-2025, https://doi.org/10.5194/amt-18-2425-2025, 2025
Short summary
Short summary
Laser desorption of individual particles prior to ionization is the key to reveal their organic composition. The CO2 lasers required are bulky and maintenance-intensive, limiting their use in the field. We have developed a compact solid-state IR laser that is easily aligned with the particle beam. Mass spectra and hit rates are similar to those of the CO2 laser. For combined characterization of organic and inorganic particle compositions, both lasers are superior to conventional single UV pulses.
Teresa Laurita, Alessandro Mauceri, Francesco Cardellicchio, Emilio Lapenna, Benedetto De Rosa, Serena Trippetta, Michail Mytilinaios, Davide Amodio, Aldo Giunta, Ermann Ripepi, Canio Colangelo, Nikolaos Papagiannopoulos, Francesca Morrongiello, Claudio Dema, Simone Gagliardi, Carmela Cornacchia, Rosa Maria Petracca Altieri, Aldo Amodeo, Marco Rosoldi, Donato Summa, Gelsomina Pappalardo, and Lucia Mona
Atmos. Meas. Tech., 18, 2373–2396, https://doi.org/10.5194/amt-18-2373-2025, https://doi.org/10.5194/amt-18-2373-2025, 2025
Short summary
Short summary
This paper provides an overview of the CIAO Observatory in southern Italy, focusing on the upgrade of its aerosol in situ laboratory in compliance with ACTRIS standard operating procedures. The aim is to provide the aerosol research community with technical details and practical guidance for establishing an in situ aerosol observational site. The paper also discusses the importance of combining in situ and remote sensing measurements for a comprehensive understanding of atmospheric processes.
Silvia Nava, Roberta Vecchi, Paolo Prati, Vera Bernardoni, Laura Cadeo, Giulia Calzolai, Luca Carraresi, Carlo Cialdai, Massimo Chiari, Federica Crova, Alice Forello, Cosimo Fratticioli, Fabio Giardi, Marco Manetti, Dario Massabò, Federico Mazzei, Luca Repetto, Gianluigi Valli, Virginia Vernocchi, and Franco Lucarelli
Atmos. Meas. Tech., 18, 2137–2147, https://doi.org/10.5194/amt-18-2137-2025, https://doi.org/10.5194/amt-18-2137-2025, 2025
Short summary
Short summary
The new high-time-resolution sampler STRAS has been designed, developed and tested. It enables automatic sequential sampling of up to 168 hourly samples of PM10, PM2.5 or PM1. It has been conceived for subsequent elemental composition analysis (from Na to Pb) by particle-induced X-ray emission (PIXE), but optical techniques may also be applied to measure black and brown carbon. Its use combined with other high-temporal-resolution instrumentation can provide complete chemical speciation of aerosols on an hourly basis.
Lasse Moormann, Thomas Böttger, Philipp Schuhmann, Luis Valero, Friederike Fachinger, and Frank Drewnick
Atmos. Meas. Tech., 18, 1441–1459, https://doi.org/10.5194/amt-18-1441-2025, https://doi.org/10.5194/amt-18-1441-2025, 2025
Short summary
Short summary
The drone-based Flying Laboratory FLab was developed to simultaneously measure aerosol (number concentration, size distribution, and black carbon), trace gas (O3, CO2), and meteorological variables. FLab was characterized in the field regarding limitations and biases due to different flight maneuvers. Two application cases are presented: analysis of the development of the lowermost troposphere (up to 300 m) and successfully bridging ground-based and aircraft- and radiosonde-based measurements.
Zsófia Jurányi, Christof Lüpkes, Frank Stratmann, Jörg Hartmann, Jonas Schaefer, Anna-Marie Jörss, Alexander Schulz, Bruno Wetzel, David Simon, Eduard Gebhard, Maximilian Stöhr, Paula Hofmann, Dirk Kalmbach, Sarah Grawe, and Andreas Herber
EGUsphere, https://doi.org/10.5194/egusphere-2025-619, https://doi.org/10.5194/egusphere-2025-619, 2025
Short summary
Short summary
Understanding the lowest layers of the atmosphere is crucial for climate research, especially in the Arctic. Our study introduces the T-Bird, an aircraft-towed platform designed to measure turbulence and aerosol properties at extremely low altitudes. Traditional aircraft cannot access this region, making the T-Bird a breakthrough for capturing critical atmospheric data. Its first deployment over the Arctic demonstrated its potential to improve our understanding of polar processes.
Darren Cheng, Stavros Amanatidis, Gregory S. Lewis, and Coty N. Jen
Atmos. Meas. Tech., 18, 197–210, https://doi.org/10.5194/amt-18-197-2025, https://doi.org/10.5194/amt-18-197-2025, 2025
Short summary
Short summary
This study describes a new method, the Condensation Particle Counters For Atmospheric Rapid Measurements (CPC FARM), to measure sub-3 nm size distribution at high time resolution and sensitivity. The CPC FARM is compared to traditionally used particle mobility sizers during a new particle formation campaign to study rapidly changing sub-3 nm particles in Pittsburgh, PA.
Ivonne Trebs, Céline Lett, Andreas Krein, Erika Matsumoto Kawaguchi, and Jürgen Junk
Atmos. Meas. Tech., 17, 6791–6805, https://doi.org/10.5194/amt-17-6791-2024, https://doi.org/10.5194/amt-17-6791-2024, 2024
Short summary
Short summary
This study explores the effectiveness of the Horiba PX-375 monitor for analysing the elemental composition of airborne particulate matter (PM). Understanding this composition of PM is important for identifying its sources, assessing potential health risks, and developing strategies to reduce air pollution. The PX-375 monitor proved to be a valuable tool for ongoing air quality monitoring studies and could be particularly useful as pollution levels and sources change in the future.
Wei-Chieh Huang, Hui-Ming Hung, Ching-Wei Chu, Wei-Chun Hwang, and Shih-Chun Candice Lung
Atmos. Meas. Tech., 17, 6073–6084, https://doi.org/10.5194/amt-17-6073-2024, https://doi.org/10.5194/amt-17-6073-2024, 2024
Short summary
Short summary
This study investigates aerosol properties crucial for health, cloud formation, and climate impact. Employing a low-cost sensor system, we assess hygroscopicity of particulate matter (PM) and the ability to influence cloud formation to improve the reported PM concentrations from low-cost sensors. The study introduces an alternate methodology for assessing aerosol hygroscopicity, offering insights into atmospheric science, air quality, and cloud dynamics.
Simon Thivet, Gholamhossein Bagheri, Przemyslaw M. Kornatowski, Allan Fries, Jonathan Lemus, Riccardo Simionato, Carolina Díaz-Vecino, Eduardo Rossi, Taishi Yamada, Simona Scollo, and Costanza Bonadonna
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-162, https://doi.org/10.5194/amt-2024-162, 2024
Revised manuscript accepted for AMT
Short summary
Short summary
This work presents an innovative way of sampling and analyzing volcanic clouds using an Unoccupied Aircraft System (UAS). The UAS can reach hazardous environments to sample volcanic particles, and measure in-situ key parameters such as the atmospheric concentration of volcanic aerosols and gases. Acquired data bridge the gap between the existing approaches of ground sampling and remote sensing, hence contributing to the understanding of volcanic cloud dispersion and impact.
Alexander Julian Böhmländer, Larissa Lacher, David Brus, Konstantinos-Matthaios Doulgeris, Zoé Brasseur, Matthew Boyer, Joel Kuula, Thomas Leisner, and Ottmar Möhler
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-120, https://doi.org/10.5194/amt-2024-120, 2024
Revised manuscript accepted for AMT
Short summary
Short summary
Clouds and aerosol are important for weather and climate. Typically, pure water cloud droplets stay liquid until around -35 °C, unless they come into contact with ice-nucleating particles (INPs). INPs are a rare subset of aerosol particles. Using uncrewed aerial vehicles (UAVs), it is possible to collect aerosol particles and analyse them on their ice-nucleating ability. This study describes the test and validation of a sampling setup that can be used to collect aerosol particles onto a filter.
Adrien Pineau, Henriette Trollvik, Herman Greaker, Sveinung Olsen, Yngve Eilertsen, and Ingrid Mann
Atmos. Meas. Tech., 17, 3843–3861, https://doi.org/10.5194/amt-17-3843-2024, https://doi.org/10.5194/amt-17-3843-2024, 2024
Short summary
Short summary
The mesosphere, part of the upper atmosphere, contains small solid dust particles, mostly made up of material from interplanetary space. We are preparing an experiment to collect such particles during a rocket flight. A new instrument has been designed and numerical simulations have been performed to investigate the airflow nearby as well as its dust collection efficiency. The collected dust particles will be further analyzed in the laboratory in order to study their chemical composition.
Chenjie Yu, Edouard Pangui, Kevin Tu, Mathieu Cazaunau, Maxime Feingesicht, Landsheere Xavier, Thierry Bourrianne, Vincent Michoud, Christopher Cantrell, Timothy B. Onasch, Andrew Freedman, and Paola Formenti
Atmos. Meas. Tech., 17, 3419–3437, https://doi.org/10.5194/amt-17-3419-2024, https://doi.org/10.5194/amt-17-3419-2024, 2024
Short summary
Short summary
To meet the requirements for measuring aerosol optical properties on airborne platforms and conducting dual-wavelength measurements, we introduced A2S2, an airborne dual-wavelength cavity-attenuated phase-shift single monitor. This study reports the results in the laboratory and an aircraft campaign over Paris and its surrounding regions. The results demonstrate A2S2's reliability in measuring aerosol optical properties at both wavelengths and its suitability for future aircraft campaigns.
Patricia K. Quinn, Timothy S. Bates, Derek J. Coffman, James E. Johnson, and Lucia M. Upchurch
Atmos. Meas. Tech., 17, 3157–3170, https://doi.org/10.5194/amt-17-3157-2024, https://doi.org/10.5194/amt-17-3157-2024, 2024
Short summary
Short summary
An uncrewed aerial observing system has been developed for the measurement of vertical profiles of aerosol and cloud properties that affect Earth's radiation balance. The system was successfully deployed from a ship and from a coastal site and flown autonomously up to 3050 m and for 4.5 h. These results indicate the potential of the observing system to make routine, operational flights from ships and land to characterize aerosol interactions with radiation and clouds.
Manuel Schöberl, Maximilian Dollner, Josef Gasteiger, Petra Seibert, Anne Tipka, and Bernadett Weinzierl
Atmos. Meas. Tech., 17, 2761–2776, https://doi.org/10.5194/amt-17-2761-2024, https://doi.org/10.5194/amt-17-2761-2024, 2024
Short summary
Short summary
Transporting a representative aerosol sample to instrumentation inside a research aircraft remains a challenge due to losses or enhancements of particles in the aerosol sampling system. Here, we present sampling efficiencies and the cutoff diameter for the DLR Falcon aerosol sampling system as a function of true airspeed by comparing the in-cabin and the out-cabin particle number size distributions observed during the A-LIFE aircraft mission.
Markus Knoll, Martin Penz, Hannes Juchem, Christina Schmidt, Denis Pöhler, and Alexander Bergmann
Atmos. Meas. Tech., 17, 2481–2505, https://doi.org/10.5194/amt-17-2481-2024, https://doi.org/10.5194/amt-17-2481-2024, 2024
Short summary
Short summary
Exhaust emissions from combustion-based vehicles are negatively affecting human health and our environment. In particular, a small share (< 20 %) of poorly maintained or tampered vehicles are responsible for the majority (60 %–90 %) of traffic-related emissions. The emissions from vehicles are currently not properly monitored during their lifetime. We present a roadside measurement technique, called
point sampling, which can be used to monitor vehicle emissions throughout their life cycle.
Claudio Crazzolara and Andreas Held
Atmos. Meas. Tech., 17, 2183–2194, https://doi.org/10.5194/amt-17-2183-2024, https://doi.org/10.5194/amt-17-2183-2024, 2024
Short summary
Short summary
Our paper describes the development of a collection device that can be used to collect airborne dust particles classified according to their size. This collection device is optimized for a special analysis method based on X-ray fluorescence so that particles can be collected from the air and analyzed with high sensitivity. This enables the determination of the content of heavy metals in the airborne particle fraction, which are of health-relevant significance.
Roman Pohorsky, Andrea Baccarini, Julie Tolu, Lenny H. E. Winkel, and Julia Schmale
Atmos. Meas. Tech., 17, 731–754, https://doi.org/10.5194/amt-17-731-2024, https://doi.org/10.5194/amt-17-731-2024, 2024
Short summary
Short summary
This manuscript presents a new tethered-balloon-based platform for in situ vertical measurements of aerosols and trace gases in the lower atmosphere of polar and alpine regions. The system can host various instrumental setups to target different research questions and features new instruments, in particular a miniaturized scanning electrical mobility spectrometer, deployed for the first time in a tethered balloon.
Anna J. Miller, Fabiola Ramelli, Christopher Fuchs, Nadja Omanovic, Robert Spirig, Huiying Zhang, Ulrike Lohmann, Zamin A. Kanji, and Jan Henneberger
Atmos. Meas. Tech., 17, 601–625, https://doi.org/10.5194/amt-17-601-2024, https://doi.org/10.5194/amt-17-601-2024, 2024
Short summary
Short summary
We present a method for aerosol and cloud research using two uncrewed aerial vehicles (UAVs). The UAVs have a propeller heating mechanism that allows flights in icing conditions, which has so far been a limitation for cloud research with UAVs. One UAV burns seeding flares, producing a plume of particles that causes ice formation in supercooled clouds. The second UAV measures aerosol size distributions and is used for measuring the seeding plume or for characterizing the boundary layer.
Sophie Erb, Elias Graf, Yanick Zeder, Simone Lionetti, Alexis Berne, Bernard Clot, Gian Lieberherr, Fiona Tummon, Pascal Wullschleger, and Benoît Crouzy
Atmos. Meas. Tech., 17, 441–451, https://doi.org/10.5194/amt-17-441-2024, https://doi.org/10.5194/amt-17-441-2024, 2024
Short summary
Short summary
In this study, we focus on an automatic bioaerosol measurement instrument and investigate the impact of using its fluorescence measurement for pollen identification. The fluorescence signal is used together with a pair of images from the same instrument to identify single pollen grains via neural networks. We test whether considering fluorescence as a supplementary input improves the pollen identification performance by comparing three different neural networks.
Miguel Ricardo A. Hilario, Avelino F. Arellano, Ali Behrangi, Ewan C. Crosbie, Joshua P. DiGangi, Glenn S. Diskin, Michael A. Shook, Luke D. Ziemba, and Armin Sorooshian
Atmos. Meas. Tech., 17, 37–55, https://doi.org/10.5194/amt-17-37-2024, https://doi.org/10.5194/amt-17-37-2024, 2024
Short summary
Short summary
Wet scavenging strongly influences aerosol lifetime and interactions but is a large uncertainty in global models. We present a method to identify meteorological variables relevant for estimating wet scavenging. During long-range transport over the tropical western Pacific, relative humidity and the frequency of humid conditions are better predictors of scavenging than precipitation. This method can be applied to other regions, and our findings can inform scavenging parameterizations in models.
Sarah Grawe, Conrad Jentzsch, Jonas Schaefer, Heike Wex, Stephan Mertes, and Frank Stratmann
Atmos. Meas. Tech., 16, 4551–4570, https://doi.org/10.5194/amt-16-4551-2023, https://doi.org/10.5194/amt-16-4551-2023, 2023
Short summary
Short summary
Measurements of ice-nucleating particle (INP) concentrations are valuable for the simulation of cloud properties. In recent years, filter sampling in combination with offline INP measurements has become increasingly popular. However, most sampling is ground-based, and the vertical transport of INPs is not well quantified. The High-volume flow aERosol particle filter sAmpler (HERA) for applications on board aircraft was developed to expand the sparse dataset of INP concentrations at cloud level.
Dimitri Castarède, Zoé Brasseur, Yusheng Wu, Zamin A. Kanji, Markus Hartmann, Lauri Ahonen, Merete Bilde, Markku Kulmala, Tuukka Petäjä, Jan B. C. Pettersson, Berko Sierau, Olaf Stetzer, Frank Stratmann, Birgitta Svenningsson, Erik Swietlicki, Quynh Thu Nguyen, Jonathan Duplissy, and Erik S. Thomson
Atmos. Meas. Tech., 16, 3881–3899, https://doi.org/10.5194/amt-16-3881-2023, https://doi.org/10.5194/amt-16-3881-2023, 2023
Short summary
Short summary
Clouds play a key role in Earth’s climate by influencing the surface energy budget. Certain types of atmospheric aerosols, called ice-nucleating particles (INPs), induce the formation of ice in clouds and, thus, often initiate precipitation formation. The Portable Ice Nucleation Chamber 2 (PINCii) is a new instrument developed to study ice formation and to conduct ambient measurements of INPs, allowing us to investigate the sources and properties of the atmospheric aerosols that can act as INPs.
Franz Martin Schnaiter, Claudia Linke, Eija Asmi, Henri Servomaa, Antti-Pekka Hyvärinen, Sho Ohata, Yutaka Kondo, and Emma Järvinen
Atmos. Meas. Tech., 16, 2753–2769, https://doi.org/10.5194/amt-16-2753-2023, https://doi.org/10.5194/amt-16-2753-2023, 2023
Short summary
Short summary
Light-absorbing particles from combustion processes are important contributors to climate warming. Their highly variable spectral light absorption properties need to be monitored in the field. Commonly used methods show measurement artefacts that are difficult to correct. We introduce a new instrument that is based on the photoacoustic effect. Long-term operation in the Finnish Arctic demonstrates the applicability of the new instrument for unattended light absorption monitoring.
Dominik Stolzenburg, Tiia Laurila, Pasi Aalto, Joonas Vanhanen, Tuukka Petäjä, and Juha Kangasluoma
Atmos. Meas. Tech., 16, 2471–2483, https://doi.org/10.5194/amt-16-2471-2023, https://doi.org/10.5194/amt-16-2471-2023, 2023
Short summary
Short summary
Size-distribution measurements of ultrafine particles are of special interest as they can be used to estimate the atmospheric significance of new particle formation, a process which is thought to influence the global climate. Here we show that improved counting statistics in size-distribution measurements through the usage of higher sampling flows can significantly reduce the uncertainties in such calculations.
Kamaljeet Kaur and Kerry E. Kelly
Atmos. Meas. Tech., 16, 2455–2470, https://doi.org/10.5194/amt-16-2455-2023, https://doi.org/10.5194/amt-16-2455-2023, 2023
Short summary
Short summary
We evaluated the AlphaSense OPC-N3 and PMS5003 compared to federal equivalent method (FEM) PM10 measurements in the Salt Lake Valley during five dust events. Before correction, the OPC-N3 agreed well, but the PMS PM10 measurements correlated poorly with the FEM. After correcting the PMS with a PM2.5 / PM10 ratio-based factor, the PMS PM10 correlations improved significantly. This suggests the possibility of better resolved spatial estimates of PM10 using PMS measurements and PM2.5 / PM10 ratios.
Balint Alfoldy, Asta Gregorič, Matic Ivančič, Irena Ježek, and Martin Rigler
Atmos. Meas. Tech., 16, 135–152, https://doi.org/10.5194/amt-16-135-2023, https://doi.org/10.5194/amt-16-135-2023, 2023
Short summary
Short summary
Atmospheric concentrations and source apportionment (SA) of black carbon (BC) and CO2 were determined in an urban environment during a heating season. BC particles were attributed to two major sources: traffic and heating. The BC SA was implemented by an Aethalometer model used for the SA of CO2 supposing that the source-specific CO2 components are correlated with the corresponding BC. Source-specific emission factors were determined as a ratio of corresponding BC and CO2 components.
Christian Pilz, Sebastian Düsing, Birgit Wehner, Thomas Müller, Holger Siebert, Jens Voigtländer, and Michael Lonardi
Atmos. Meas. Tech., 15, 6889–6905, https://doi.org/10.5194/amt-15-6889-2022, https://doi.org/10.5194/amt-15-6889-2022, 2022
Short summary
Short summary
Tethered balloon observations are highly valuable for aerosol studies in the lowest part of the atmosphere. This study presents a newly developed platform called CAMP with four aerosol instruments for balloon-borne measurements in the Arctic. Laboratory characterizations and evaluations of the instruments and results of a first field deployment are shown. A case study highlights CAMP's capabilities and the importance of airborne aerosol studies for interpretation of ground-based observations.
Weilun Zhao, Gang Zhao, Ying Li, Song Guo, Nan Ma, Lizi Tang, Zirui Zhang, and Chunsheng Zhao
Atmos. Meas. Tech., 15, 6807–6817, https://doi.org/10.5194/amt-15-6807-2022, https://doi.org/10.5194/amt-15-6807-2022, 2022
Short summary
Short summary
A new method to determine black carbon mass size distribution (BCMSD) was proposed using the size-resolved absorption coefficient measured by an aerodynamic aerosol classifier in tandem with an aethalometer. This new method fills the gap in the high-time-resolution measurement of BCMSD ranging from upper submicron particle sizes to larger than 1 µm. This method can be applied to field measurement of BCMSD extensively for better understanding BC aging and better estimating the BC climate effect.
Antonis Dragoneas, Sergej Molleker, Oliver Appel, Andreas Hünig, Thomas Böttger, Markus Hermann, Frank Drewnick, Johannes Schneider, Ralf Weigel, and Stephan Borrmann
Atmos. Meas. Tech., 15, 5719–5742, https://doi.org/10.5194/amt-15-5719-2022, https://doi.org/10.5194/amt-15-5719-2022, 2022
Short summary
Short summary
The ERICA is a specially designed aerosol particle mass spectrometer for in situ, real-time chemical composition analysis of aerosols. It can operate completely autonomously, in the absence of an instrument operator. Its design has enabled its operation under harsh conditions, like those experienced in the upper troposphere and lower stratosphere, aboard unpressurized high-altitude research aircraft. The instrument has successfully participated in several aircraft operations around the world.
Dimitrios Bousiotis, David C. S. Beddows, Ajit Singh, Molly Haugen, Sebastián Diez, Pete M. Edwards, Adam Boies, Roy M. Harrison, and Francis D. Pope
Atmos. Meas. Tech., 15, 4047–4061, https://doi.org/10.5194/amt-15-4047-2022, https://doi.org/10.5194/amt-15-4047-2022, 2022
Short summary
Short summary
In the last decade, low-cost sensors have revolutionised the field of air quality monitoring. This paper extends the ability of low-cost sensors to not only measure air pollution, but also to understand where the pollution comes from. This "source apportionment" is a critical step in air quality management to allow for the mitigation of air pollution. The techniques developed in this paper have the potential for great impact in both research and industrial applications.
Luka Drinovec, Uroš Jagodič, Luka Pirker, Miha Škarabot, Mario Kurtjak, Kristijan Vidović, Luca Ferrero, Bradley Visser, Jannis Röhrbein, Ernest Weingartner, Daniel M. Kalbermatter, Konstantina Vasilatou, Tobias Bühlmann, Celine Pascale, Thomas Müller, Alfred Wiedensohler, and Griša Močnik
Atmos. Meas. Tech., 15, 3805–3825, https://doi.org/10.5194/amt-15-3805-2022, https://doi.org/10.5194/amt-15-3805-2022, 2022
Short summary
Short summary
A new photothermal interferometer (PTAAM-2λ) for artefact-free determination of the aerosol absorption coefficient at two wavelengths is presented. The instrument is calibrated with NO2 and polydisperse nigrosin, resulting in very low uncertainties of the absorption coefficients: 4 % at 532 nm and 6 % at 1064 nm. The instrument’s performance makes the PTAAM-2λ a strong candidate for reference measurements of the aerosol absorption coefficient.
Markus Leiminger, Lukas Fischer, Sophia Brilke, Julian Resch, Paul Martin Winkler, Armin Hansel, and Gerhard Steiner
Atmos. Meas. Tech., 15, 3705–3720, https://doi.org/10.5194/amt-15-3705-2022, https://doi.org/10.5194/amt-15-3705-2022, 2022
Short summary
Short summary
We developed an axial ion mobility classifier coupled to an atmospheric-pressure interface time-of-flight (APi-TOF) mass spectrometer to measure size-segregated atmospheric ions. We characterize the performance of the novel instrument with bipolar-electrospray-generated ion mobility standards and compare the results with CFD simulations and a simplified numerical particle-tracking model. Ultimately, we report first mass–mobility measurements of atmospheric ions in Innsbruck, Austria.
Andreas Hünig, Oliver Appel, Antonis Dragoneas, Sergej Molleker, Hans-Christian Clemen, Frank Helleis, Thomas Klimach, Franziska Köllner, Thomas Böttger, Frank Drewnick, Johannes Schneider, and Stephan Borrmann
Atmos. Meas. Tech., 15, 2889–2921, https://doi.org/10.5194/amt-15-2889-2022, https://doi.org/10.5194/amt-15-2889-2022, 2022
Short summary
Short summary
We have serially combined the two well-established methods for in situ real-time measurement of fine particle chemical composition, the single-particle laser ablation method and the flash evaporation with electron impact ionization method, into a novel instrument. Here we present the design; instrument characteristics, as derived from laboratory and field measurements; and results from the first field deployment during the 2017 StratoClim aircraft campaign.
Christopher D. Wallis, Mason D. Leandro, Patrick Y. Chuang, and Anthony S. Wexler
Atmos. Meas. Tech., 15, 2547–2556, https://doi.org/10.5194/amt-15-2547-2022, https://doi.org/10.5194/amt-15-2547-2022, 2022
Short summary
Short summary
Measuring emissions from stacks requires techniques to address a broad range of conditions and measurement challenges. Here we describe an instrument package held by a crane above a stack to characterize both wet droplet and dried aerosol emissions from cooling tower spray drift in situ. The instrument package characterizes the velocity, size distribution, and concentration of the wet droplet emissions and the mass concentration and elemental composition of the dried PM2.5 and PM10 emissions.
Karin Ardon-Dryer, Mary C. Kelley, Xia Xueting, and Yuval Dryer
Atmos. Meas. Tech., 15, 2345–2360, https://doi.org/10.5194/amt-15-2345-2022, https://doi.org/10.5194/amt-15-2345-2022, 2022
Short summary
Short summary
The Aerosol Research Observation Station (AEROS) located in West Texas was designed to continuously measure atmospheric particles, including different particulate matter sizes, total particle number concentration, and size distribution. This article provides a description of AEROS as well as an intercomparison of the different instruments using laboratory and atmospheric particles, showing similar concentration as well to distinguish between various pollution events (natural vs. anthropogenic).
Adam T. Ahern, Frank Erdesz, Nicholas L. Wagner, Charles A. Brock, Ming Lyu, Kyra Slovacek, Richard H. Moore, Elizabeth B. Wiggins, and Daniel M. Murphy
Atmos. Meas. Tech., 15, 1093–1105, https://doi.org/10.5194/amt-15-1093-2022, https://doi.org/10.5194/amt-15-1093-2022, 2022
Short summary
Short summary
Particles in the atmosphere play a significant role in climate change by scattering light back into space, reducing the amount of energy available to be absorbed by greenhouse gases. We built a new instrument to measure what direction light is scattered by particles, e.g., wildfire smoke. This is important because, depending on the angle of the sun, some particles scatter light into space (cooling the planet), but some light is also scattered towards the Earth (not cooling the planet).
Yuya Kobayashi and Nobuyuki Takegawa
Atmos. Meas. Tech., 15, 833–844, https://doi.org/10.5194/amt-15-833-2022, https://doi.org/10.5194/amt-15-833-2022, 2022
Short summary
Short summary
We propose a new method to quantify particulate sodium and potassium salts (nitrate, chloride, and sulfate) by using a refractory aerosol thermal desorption mass spectrometer (rTDMS). The combination of a graphite particle collector and a carbon dioxide laser enables high desorption temperature. Laboratory experiments showed that major ion signals originating from sodium or potassium salts were clearly detected, associated with the increase in the desorption temperature by laser heating.
James R. Ouimette, William C. Malm, Bret A. Schichtel, Patrick J. Sheridan, Elisabeth Andrews, John A. Ogren, and W. Patrick Arnott
Atmos. Meas. Tech., 15, 655–676, https://doi.org/10.5194/amt-15-655-2022, https://doi.org/10.5194/amt-15-655-2022, 2022
Short summary
Short summary
We show that the low-cost PurpleAir sensor can be characterized as a cell-reciprocal nephelometer. At two very different locations (Mauna Loa Observatory in Hawaii and the Table Mountain rural site in Colorado), the PurpleAir measurements are highly correlated with the submicrometer aerosol scattering coefficient measured by a research-grade integrating nephelometer. These results imply that, with care, PurpleAir data may be used to evaluate climate and air quality models.
Steven G. Howell, Steffen Freitag, Amie Dobracki, Nikolai Smirnow, and Arthur J. Sedlacek III
Atmos. Meas. Tech., 14, 7381–7404, https://doi.org/10.5194/amt-14-7381-2021, https://doi.org/10.5194/amt-14-7381-2021, 2021
Short summary
Short summary
Small particles in the air have important effects on visibility, clouds, and human health. For the ORACLES project we got a new particle sizing instrument that is fast, works over the most important particle sizes, and avoids some of the issues that plague other optical particle sizers. Unfortunately it sees some particles much smaller than they really are, likely because they heat up and evaporate. We show a crude correction and speculate why these particles heat up much more than expected.
Jeffrey K. Bean
Atmos. Meas. Tech., 14, 7369–7379, https://doi.org/10.5194/amt-14-7369-2021, https://doi.org/10.5194/amt-14-7369-2021, 2021
Short summary
Short summary
Understanding and improving the quality of data generated from low-cost air quality sensors are crucial steps in using these sensors. This work investigates how averaging time, choice of reference instrument, and the observation of higher pollutant concentrations can impact the perceived performance of low-cost sensors in an evaluation. The influence of these factors should be considered when comparing one sensor to another or determining if a sensor can produce data that fit a specific need.
Fan Mei, Steven Spielman, Susanne Hering, Jian Wang, Mikhail S. Pekour, Gregory Lewis, Beat Schmid, Jason Tomlinson, and Maynard Havlicek
Atmos. Meas. Tech., 14, 7329–7340, https://doi.org/10.5194/amt-14-7329-2021, https://doi.org/10.5194/amt-14-7329-2021, 2021
Short summary
Short summary
This study focuses on understanding a versatile water-based condensation particle counter (vWCPC 3789) performance under various ambient pressure conditions (500–1000 hPa). A vWCPC has the advantage of avoiding health and safety concerns. However, its performance characterization under low pressure is rare but crucial for ensuring successful airborne deployment. This paper provides advanced knowledge of operating a vWCPC 3789 to capture the spatial variations of atmospheric aerosols.
Rebecca A. Wernis, Nathan M. Kreisberg, Robert J. Weber, Yutong Liang, John Jayne, Susanne Hering, and Allen H. Goldstein
Atmos. Meas. Tech., 14, 6533–6550, https://doi.org/10.5194/amt-14-6533-2021, https://doi.org/10.5194/amt-14-6533-2021, 2021
Short summary
Short summary
cTAG is a new scientific instrument that measures concentrations of organic chemicals in the atmosphere. cTAG is the first instrument capable of measuring small, light chemicals as well as heavier chemicals and everything in between on a single detector, every hour. In this work we explain how cTAG works and some of the tests we performed to verify that it works properly and reliably. We also present measurements of alkanes that suggest they have three dominant sources in a Bay Area suburb.
Linghan Zeng, Amy P. Sullivan, Rebecca A. Washenfelder, Jack Dibb, Eric Scheuer, Teresa L. Campos, Joseph M. Katich, Ezra Levin, Michael A. Robinson, and Rodney J. Weber
Atmos. Meas. Tech., 14, 6357–6378, https://doi.org/10.5194/amt-14-6357-2021, https://doi.org/10.5194/amt-14-6357-2021, 2021
Short summary
Short summary
Three online systems for measuring water-soluble brown carbon are compared. A mist chamber and two different particle-into-liquid samplers were deployed on separate research aircraft targeting wildfires and followed a similar detection method using a long-path liquid waveguide with a spectrometer to measure the light absorption from 300 to 700 nm. Detection limits, signal hysteresis and other sampling issues are compared, and further improvements of these liquid-based systems are provided.
Zixia Liu, Martin Osborne, Karen Anderson, Jamie D. Shutler, Andy Wilson, Justin Langridge, Steve H. L. Yim, Hugh Coe, Suresh Babu, Sreedharan K. Satheesh, Paquita Zuidema, Tao Huang, Jack C. H. Cheng, and James Haywood
Atmos. Meas. Tech., 14, 6101–6118, https://doi.org/10.5194/amt-14-6101-2021, https://doi.org/10.5194/amt-14-6101-2021, 2021
Short summary
Short summary
This paper first validates the performance of an advanced aerosol observation instrument POPS against a reference instrument and examines any biases introduced by operating it on a quadcopter drone. The results show the POPS performs relatively well on the ground. The impact of the UAV rotors on the POPS is small at low wind speeds, but when operating under higher wind speeds, larger discrepancies occur. It appears that the POPS measures sub-micron aerosol particles more accurately on the UAV.
Eric A. Wendt, Casey Quinn, Christian L'Orange, Daniel D. Miller-Lionberg, Bonne Ford, Jeffrey R. Pierce, John Mehaffy, Michael Cheeseman, Shantanu H. Jathar, David H. Hagan, Zoey Rosen, Marilee Long, and John Volckens
Atmos. Meas. Tech., 14, 6023–6038, https://doi.org/10.5194/amt-14-6023-2021, https://doi.org/10.5194/amt-14-6023-2021, 2021
Short summary
Short summary
Fine particulate matter air pollution is one of the leading contributors to adverse health outcomes on the planet. Here, we describe the design and validation of a low-cost, compact, and autonomous instrument capable of measuring particulate matter levels directly, via mass sampling, and optically, via mass and sunlight extinction measurements. We demonstrate the instrument's accuracy relative to reference measurements and its potential for community-level sampling.
Jiaoshi Zhang, Steven Spielman, Yang Wang, Guangjie Zheng, Xianda Gong, Susanne Hering, and Jian Wang
Atmos. Meas. Tech., 14, 5625–5635, https://doi.org/10.5194/amt-14-5625-2021, https://doi.org/10.5194/amt-14-5625-2021, 2021
Short summary
Short summary
In this study, we present a newly developed instrument, the humidity-controlled fast integrated mobility spectrometer (HFIMS), for fast measurements of aerosol hygroscopic growth. The HFIMS can measure the distributions of particle hygroscopic growth factors at six diameters from 35 to 265 nm under five RH levels from 20 to 85 % within 25 min. The HFIMS significantly advances our capability of characterizing the hygroscopic growth of atmospheric aerosols over a wide range of relative humidities.
Johannes Passig, Julian Schade, Robert Irsig, Lei Li, Xue Li, Zhen Zhou, Thomas Adam, and Ralf Zimmermann
Atmos. Meas. Tech., 14, 4171–4185, https://doi.org/10.5194/amt-14-4171-2021, https://doi.org/10.5194/amt-14-4171-2021, 2021
Short summary
Short summary
Ships are major sources of air pollution; however, monitoring of ship emissions outside harbours is a challenging task. We optimized single-particle mass spectrometry (SPMS) for the detection of bunker fuel emissions and demonstrate the detection of individual ship plumes from more than 10 km in distance. The approach works independently of background air pollution and also when ships use exhaust-cleaning scrubbers. We discuss the potential and limits of SPMS-based monitoring of ship plumes.
Mengying Bao, Yan-Lin Zhang, Fang Cao, Yu-Chi Lin, Yuhang Wang, Xiaoyan Liu, Wenqi Zhang, Meiyi Fan, Feng Xie, Robert Cary, Joshua Dixon, and Lihua Zhou
Atmos. Meas. Tech., 14, 4053–4068, https://doi.org/10.5194/amt-14-4053-2021, https://doi.org/10.5194/amt-14-4053-2021, 2021
Short summary
Short summary
We introduce a two-wavelength method for brown C measurements with a modified Sunset carbon analyzer. We defined the enhanced concentrations and gave the possibility of providing an indicator of brown C. Compared with the strong local sources of organic and elemental C, we found that differences in EC mainly originated from regional transport. Biomass burning emissions significantly contributed to high differences in EC concentrations during the heavy biomass burning periods.
Candice L. Sirmollo, Don R. Collins, Jordan M. McCormick, Cassandra F. Milan, Matthew H. Erickson, James H. Flynn, Rebecca J. Sheesley, Sascha Usenko, Henry W. Wallace, Alexander A. T. Bui, Robert J. Griffin, Matthew Tezak, Sean M. Kinahan, and Joshua L. Santarpia
Atmos. Meas. Tech., 14, 3351–3370, https://doi.org/10.5194/amt-14-3351-2021, https://doi.org/10.5194/amt-14-3351-2021, 2021
Short summary
Short summary
The newly developed portable 1 m3 CAGE chamber systems were characterized using data acquired during a 2-month field study in 2016 in a forested area north of Houston, TX, USA. Concentrations of several oxidant and organic compounds measured in the chamber were found to closely agree with those calculated with a zero-dimensional model. By tracking the modes of injected monodisperse particles, a pattern change was observed for hourly averaged growth rates between late summer and early fall.
Ningjin Xu and Don R. Collins
Atmos. Meas. Tech., 14, 2891–2906, https://doi.org/10.5194/amt-14-2891-2021, https://doi.org/10.5194/amt-14-2891-2021, 2021
Short summary
Short summary
Oxidation flow reactors (OFRs) are frequently used to study atmospheric chemistry and aerosol formation by accelerating by up to 10 000 times the reactions that can take hours, days, or even weeks in the atmosphere. Here we present the design and evaluation of a new all-Teflon OFR. The computational, laboratory, and field use data we present demonstrate that the PFA OFR is suitable for a range of applications, including the study of rapidly changing ambient concentrations.
Cited articles
Arnott, W. P., Moosmüller, H., Rogers, C. F., Jin, T., and Bruch, R.:
Photoacoustic spectrometer for measuring light absorption by aerosol:
Instrument description, Atmos. Environ., 33, 2845–2852,
https://doi.org/10.1016/S1352-2310(98)00361-6, 1999.
Arnott, W. P., Moosmüller, H., and Walker, J. W.: Nitrogen dioxide and
kerosene-flame soot calibration of photoacoustic instruments for measurement
of light absorption by aerosols, Rev. Sci. Instrum., 71, 4545–4552,
https://doi.org/10.1063/1.1322585, 2000.
Axson, J. L., Washenfelder, R. A., Kahan, T. F., Young, C. J., Vaida, V., and
Brown, S. S.: Absolute ozone absorption cross section in the Huggins Chappuis
minimum (350–470 nm) at 296 K, Atmos. Chem. Phys., 11, 11581–11590,
https://doi.org/10.5194/acp-11-11581-2011, 2011.
Bahadur, R., Praveen, P. S., Xu, Y., and Ramanathan, V.: Solar absorption by
elemental and brown carbon determined from spectral observations, P. Natl.
Acad. Sci. USA, 109, 17366–17371, https://doi.org/10.1073/pnas.1205910109, 2012.
Barnard, J. C., Volkamer, R., and Kassianov, E. I.: Estimation of the mass
absorption cross section of the organic carbon component of aerosols in the
Mexico City Metropolitan Area, Atmos. Chem. Phys., 8, 6665–6679,
https://doi.org/10.5194/acp-8-6665-2008, 2008.
Baumgardner, D., Popovicheva, O., Allan, J., Bernardoni, V., Cao, J.,
Cavalli, F., Cozic, J., Diapouli, E., Eleftheriadis, K., Genberg, P. J.,
Gonzalez, C., Gysel, M., John, A., Kirchstetter, T. W., Kuhlbusch, T. A. J.,
Laborde, M., Lack, D., Müller, T., Niessner, R., Petzold, A.,
Piazzalunga, A., Putaud, J. P., Schwarz, J., Sheridan, P., Subramanian, R.,
Swietlicki, E., Valli, G., Vecchi, R., and Viana, M.: Soot reference
materials for instrument calibration and intercomparisons: a workshop summary
with recommendations, Atmos. Meas. Tech., 5, 1869–1887,
https://doi.org/10.5194/amt-5-1869-2012, 2012.
Bergstrom, R. W., Russell, P. B., and Hignett, P.: Wavelength Dependence of
the Absorption of Black Carbon Particles: Predictions and Results from the
TARFOX Experiment and Implications for the Aerosol Single Scattering Albedo,
J. Atmos. Sci., 59, 567–577,
https://doi.org/10.1175/1520-0469(2002)059<0567:WDOTAO>2.0.CO;2, 2002.
Bluvshtein, N., Flores, J. M., He, Q., Segre, E., Segev, L., Hong, N.,
Donohue, A., Hilfiker, J. N., and Rudich, Y.: Calibration of a multi-pass
photoacoustic spectrometer cell using light-absorbing aerosols, Atmos. Meas.
Tech., 10, 1203–1213, https://doi.org/10.5194/amt-10-1203-2017, 2017.
Bond, T. C. and Bergstrom, R. W.: Light Absorption by Carbonaceous Particles:
An Investigative Review, Aerosol Sci. Technol., 40, 27–67,
https://doi.org/10.1080/02786820500421521, 2006.
Bond, T. C., Anderson, T. L., and Campbell, D.: Calibration and
Intercomparison of Filter-Based Measurements of Visible Light Absorption by
Aerosols, Aerosol Sci. Technol., 30, 582–600, https://doi.org/10.1080/027868299304435,
1999.
Bond, T. C., Doherty, S. J., Fahey, D. W., Forster, P. M., Berntsen, T.,
Deangelo, B. J., Flanner, M. G., Ghan, S., Karcher, B., Koch, D., Kinne, S.,
Kondo, Y., Quinn, P. K., Sarofim, M. C., Schultz, M. G., Schulz, M.,
Venkataraman, C., Zhang, H., Zhang, S., Bellouin, N., Guttikunda, S. K.,
Hopke, P. K., Jacobson, M. Z., Kaiser, J. W., Klimont, Z., Lohmann, U.,
Schwarz, J. P., Shindell, D., Storelvmo, T., Warren, S. G., and Zender, C.
S.: Bounding the role of black carbon in the climate system: A scientific
assessment, J. Geophys. Res.-Atmos., 118, 5380–5552, https://doi.org/10.1002/jgrd.50171,
2013.
Brown, H., Liu, X., Feng, Y., Jiang, Y., Wu, M., Lu, Z., Wu, C., Murphy, S.,
and Pokhrel, R.: Radiative effect and climate impacts of brown carbon with
the Community Atmosphere Model (CAM5), Atmos. Chem. Phys., 18, 17745–17768,
https://doi.org/10.5194/acp-18-17745-2018, 2018.
Cappa, C. D., Onasch, T. B., Massoli, P., Worsnop, D. R., Bates, T. S.,
Cross, E. S., Davidovits, P., Hakala, J., Hayden, K. L., Jobson, B. T.,
Kolesar, K. R., Lack, D. A., Lerner, B. M., Li, S.-M., Mellon, D., Nuaaman,
I., Olfert, J. S., Petaja, T., Quinn, P. K., Song, C., Subramanian, R.,
Williams, E. J., and Zaveri, R. A.: Radiative Absorption Enhancements Due to
the Mixing State of Atmospheric Black Carbon, Science, 337, 1078–1081,
https://doi.org/10.1126/science.1223447, 2012.
Chakrabarty, R. K., Moosmüller, H., Chen, L.-W. A., Lewis, K., Arnott, W.
P., Mazzoleni, C., Dubey, M. K., Wold, C. E., Hao, W. M., and Kreidenweis, S.
M.: Brown carbon in tar balls from smoldering biomass combustion, Atmos.
Chem. Phys., 10, 6363–6370, https://doi.org/10.5194/acp-10-6363-2010, 2010.
Collaud Coen, M., Weingartner, E., Apituley, A., Ceburnis, D.,
Fierz-Schmidhauser, R., Flentje, H., Henzing, J. S., Jennings, S. G.,
Moerman, M., Petzold, A., Schmid, O., and Baltensperger, U.: Minimizing light
absorption measurement artifacts of the Aethalometer: evaluation of five
correction algorithms, Atmos. Meas. Tech., 3, 457–474,
https://doi.org/10.5194/amt-3-457-2010, 2010.
Davies, N. W., Cotterell, M. I., Fox, C., Szpek, K., Haywood, J. M., and
Langridge, J. M.: On the accuracy of aerosol photoacoustic spectrometer
calibrations using absorption by ozone, Atmos. Meas. Tech., 11, 2313–2324,
https://doi.org/10.5194/amt-11-2313-2018, 2018.
Feng, Y., Ramanathan, V., and Kotamarthi, V. R.: Brown carbon: a significant
atmospheric absorber of solar radiation?, Atmos. Chem. Phys., 13, 8607–8621,
https://doi.org/10.5194/acp-13-8607-2013, 2013.
Fischer, D. A. and Smith, G. D.: Can ozone be used to calibrate aerosol
photoacoustic spectrometers?, Atmos. Meas. Tech., 11, 6419–6427,
https://doi.org/10.5194/amt-11-6419-2018, 2018a.
Fischer, D. A. and Smith, G. D.: A portable, four-wavelength, single-cell
photoacoustic spectrometer for ambient aerosol absorption, Aerosol Sci.
Technol., 52, 393–406, https://doi.org/10.1080/02786826.2017.1413231, 2018b.
Forrister, H., Liu, J., Scheuer, E., Dibb, J., Ziemba, L., Thornhill, K. L.,
Anderson, B., Diskin, G., Perring, A. E., Schwarz, J. P., Campuzano-Jost, P.,
Day, D. A., Palm, B. B., Jimenez, J. L., Nenes, A., and Weber, R. J.:
Evolution of brown carbon in wildfire plumes, Geophys. Res. Lett., 42,
4623–4630, https://doi.org/10.1002/2015GL063897, 2015.
Gysel, M., Laborde, M., Olfert, J. S., Subramanian, R., and Gröhn, A. J.:
Effective density of Aquadag and fullerene soot black carbon reference
materials used for SP2 calibration, Atmos. Meas. Tech., 4, 2851–2858,
https://doi.org/10.5194/amt-4-2851-2011, 2011.
Hansen, A. D. A., Rosen, H., and Novakov, T.: The aethalometer – an
instrument for the real-time measurement of optical absorption by aerosol
particles, Sci. Total Environ., 36, 191–196, 1984.
Jacobson, M. Z.: The short-term cooling but long-term global warming due to
biomass burning, J. Climate, 17, 2909–2926,
https://doi.org/10.1175/1520-0442(2004)017<2909:TSCBLG>2.0.CO;2, 2004.
Jacobson, M. Z.: Short-term effects of controlling fossil-fuel soot, biofuel
soot and gases, and methane on climate, Arctic ice, and air pollution health,
J. Geophys. Res.-Atmos., 115, 14, https://doi.org/10.1029/2009JD013795, 2010.
Jones, I. T. N. and Bayes, K.: Photolysis of nitrogen dioxide, J. Chem.
Phys., 59, 4836, https://doi.org/10.1063/1.1680696, 1973.
Jordan, C. E., Anderson, B. E., Beyersdorf, A. J., Corr, C. A., Dibb, J. E.,
Greenslade, M. E., Martin, R. F., Moore, R. H., Scheuer, E., Shook, M. A.,
Thornhill, K. L., Troop, D., Winstead, E. L., and Ziemba, L. D.: Spectral
aerosol extinction (SpEx): a new instrument for in situ ambient aerosol
extinction measurements across the UV/visible wavelength range, Atmos. Meas.
Tech., 8, 4755–4771, https://doi.org/10.5194/amt-8-4755-2015, 2015.
Kebabian, P. L., Robinson, W. A., and Freedman, A.: Optical extinction
monitor using cw cavity enhanced detection, Rev. Sci. Instrum., 78, 063102,
https://doi.org/10.1063/1.2744223, 2007.
Kirchstetter, T. W. and Thatcher, T. L.: Contribution of organic carbon to
wood smoke particulate matter absorption of solar radiation, Atmos. Chem.
Phys., 12, 6067–6072, https://doi.org/10.5194/acp-12-6067-2012, 2012.
Kondo, Y., Sahu, L., Kuwata, M., Miyazaki, Y., Takegawa, N., Moteki, N.,
Imaru, J., Han, S., Nakayama, T., Oanh, N. T. K., Hu, M., Kim, Y. J., and
Kita, K.: Stabilization of the mass absorption cross section of black carbon
for filter-based absorption photometry by the use of a heated inlet, Aerosol
Sci. Technol., 43, 741–756, https://doi.org/10.1080/02786820902889879, 2009.
Lack, D. A., Lovejoy, E. R., Baynard, T., Pettersson, A., and Ravishankara,
A. R.: Aerosol Absorption Measurement using Photoacoustic Spectroscopy:
Sensitivity, Calibration, and Uncertainty Developments, Aerosol Sci.
Technol., 40, 697–708, https://doi.org/10.1080/02786820600803917, 2006.
Lack, D. A., Richardson, M. S., Law, D., Langridge, J. M., Cappa, C. D.,
McLaughlin, R. J., and Murphy, D. M.: Aircraft Instrument for Comprehensive
Characterization of Aerosol Optical Properties, Part 2: Black and Brown
Carbon Absorption and Absorption Enhancement Measured with Photo Acoustic
Spectroscopy, Aerosol Sci. Technol., 46, 555–568,
https://doi.org/10.1080/02786826.2011.645955, 2012a.
Lack, D. A., Langridge, J. M., Bahreini, R., Cappa, C. D., Middlebrook, A.
M., and Schwarz, J. P.: Brown carbon and internal mixing in biomass burning
particles, P. Natl. Acad. Sci. USA, 109, 14802–14807,
https://doi.org/10.1073/pnas.1206575109, 2012b.
Lack, D. A., Moosmüller, H., McMeeking, G. R., Chakrabarty, R. K., and
Baumgardner, D.: Characterizing elemental, equivalent black, and refractory
black carbon aerosol particles: A review of techniques, their limitations and
uncertainties, Anal. Bioanal. Chem., 406, 99–122,
https://doi.org/10.1007/s00216-013-7402-3, 2014.
Lee, H. J., Aiona, P. K., Laskin, A., Laskin, J., and Nizkorodov, S. A.:
Effect of Solar Radiation on the Optical Properties and Molecular Composition
of Laboratory Proxies of Atmospheric Brown Carbon, Environ. Sci. Technol.,
48, 10217–10226, https://doi.org/10.1021/es502515r, 2014.
Lin, G., Penner, J. E., Flanner, M. G., Sillman, S., Xu, L., and Zhou, C.:
Radiative forcing of organic aerosol in the atmosphere and on snow: Effects
of SOA and brown carbon, J. Geophys. Res.-Atmos., 119, 7453–7476,
https://doi.org/10.1002/2013JD021186, 2014.
Liu, J., Lin, P., Laskin, A., Laskin, J., Kathmann, S. M., Wise, M., Caylor,
R., Imholt, F., Selimovic, V., and Shilling, J. E.: Optical properties and
aging of light-absorbing secondary organic aerosol, Atmos. Chem. Phys., 16,
12815–12827, https://doi.org/10.5194/acp-16-12815-2016, 2016.
Liu, S., Aiken, A. C., Gorkowski, K., Dubey, M. K., Cappa, C. D., Williams,
L. R., Herndon, S. C., Massoli, P., Fortner, E. C., Chhabra, P. S., Brooks,
W. A., Onasch, T. B., Jayne, J. T., Worsnop, D. R., China, S., Sharma, N.,
Mazzoleni, C., Xu, L., Ng, N. L., Liu, D., Allan, J. D., Lee, J. D., Fleming,
Z. L., Mohr, C., Zotter, P., Szidat, S., and Prévôt, A. S. H.:
Enhanced light absorption by mixed source black and brown carbon particles in
UK winter, Nat. Commun., 6, 1–11, https://doi.org/10.1038/ncomms9435, 2015.
McMeeking, G. R., Fortner, E., Onasch, T. B., Taylor, J. W., Flynn, M., Coe,
H., and Kreidenweis, S. M.: Impacts of nonrefractory material on light
absorption by aerosols emitted from biomass burning, J. Geophys. Res.-Atmos.,
119, 12272–12286, https://doi.org/10.1002/2014JD021750, 2014.
Moosmüller, H., Chakrabarty, R. K., and Arnott, W. P.: Aerosol light
absorption and its measurement: A review, J. Quant. Spectrosc. Ra., 110,
844–878, https://doi.org/10.1016/j.jqsrt.2009.02.035, 2009.
Moosmüller, H., Chakrabarty, R. K., Ehlers, K. M., and Arnott, W. P.:
Absorption Ångström coefficient, brown carbon, and aerosols: basic
concepts, bulk matter, and spherical particles, Atmos. Chem. Phys., 11,
1217–1225, https://doi.org/10.5194/acp-11-1217-2011, 2011.
Müller, T., Henzing, J. S., de Leeuw, G., Wiedensohler, A., Alastuey, A.,
Angelov, H., Bizjak, M., Collaud Coen, M., Engström, J. E., Gruening, C.,
Hillamo, R., Hoffer, A., Imre, K., Ivanow, P., Jennings, G., Sun, J. Y.,
Kalivitis, N., Karlsson, H., Komppula, M., Laj, P., Li, S.-M., Lunder, C.,
Marinoni, A., Martins dos Santos, S., Moerman, M., Nowak, A., Ogren, J. A.,
Petzold, A., Pichon, J. M., Rodriquez, S., Sharma, S., Sheridan, P. J.,
Teinilä, K., Tuch, T., Viana, M., Virkkula, A., Weingartner, E., Wilhelm,
R., and Wang, Y. Q.: Characterization and intercomparison of aerosol
absorption photometers: result of two intercomparison workshops, Atmos. Meas.
Tech., 4, 245–268, https://doi.org/10.5194/amt-4-245-2011, 2011.
Nakayama, T., Sato, K., Matsumi, Y., Imamura, T., Yamazaki, A., and Uchiyama,
A.: Wavelength and NOx dependent complex refractive index of SOAs
generated from the photooxidation of toluene, Atmos. Chem. Phys., 13,
531–545, https://doi.org/10.5194/acp-13-531-2013, 2013.
Ogren, J. A., Wendell, J., Andrews, E., and Sheridan, P. J.: Continuous light
absorption photometer for long-term studies, Atmos. Meas. Tech., 10,
4805–4818, https://doi.org/10.5194/amt-10-4805-2017, 2017.
Onasch, T. B., Massoli, P., Kebabian, P. L., Hills, F. B., Bacon, F. W., and
Freedman, A.: Single Scattering Albedo Monitor for Airborne Particulates,
Aerosol Sci. Technol., 49, 267–279, https://doi.org/10.1080/02786826.2015.1022248, 2015.
Petzold, A. and Niessner, R.: Photoacoustic soot sensor for in-situ black
carbon monitoring, Appl. Phys., 63, 191–197,
https://doi.org/10.1007/BF01095272, 1996.
Rosencwaig, A.: Photoacoustic Spectroscopy, Ann. Rev. Biophys. Bioeng., 46,
207–311, https://doi.org/10.1016/S0065-2539(08)60413-8, 1980.
Saleh, R., Hennigan, C. J., McMeeking, G. R., Chuang, W. K., Robinson, E. S.,
Coe, H., Donahue, N. M., and Robinson, A. L.: Absorptivity of brown carbon in
fresh and photo-chemically aged biomass-burning emissions, Atmos. Chem.
Phys., 13, 7683–7693, https://doi.org/10.5194/acp-13-7683-2013, 2013.
Saleh, R., Robinson, E. S., Tkacik, D. S., Ahern, A. T., Liu, S., Aiken, A.
C., Sullivan, R. C., Presto, A. a., Dubey, M. K., Yokelson, R. J., Donahue,
N. M., and Robinson, A. L.: Brownness of organics in aerosols from biomass
burning linked to their black carbon content, Nat. Geosci., 7, 1–4,
https://doi.org/10.1038/ngeo2220, 2014.
Saleh, R., Marks, M., Heo, J., Adams, P. J., Donahue, N. M., and Robinson, A.
L.: Contribution of brown carbon and lensing to the direct radiative effect
of carbonaceous aerosols from biomass and biofuel burning emissions, J.
Geophys. Res.-Atmos., 120, 10285–10296, https://doi.org/10.1002/2015JD023697, 2015.
Singh, S., Fiddler, M. N., Smith, D., and Bililign, S.: Error analysis and
uncertainty in the determination of aerosol optical properties using cavity
ring-down spectroscopy, integrating nephelometry, and the
extinction-minus-scattering method, Aerosol Sci. Technol., 48, 1345–1359,
https://doi.org/10.1080/02786826.2014.984062, 2014.
Ugelow, M. S., Zarzana, K. J., Day, D. A., Jimenez, J. L., and Tolbert, M.
A.: The optical and chemical properties of discharge generated organic haze
using in-situ real-time techniques, Icarus, 294, 1–13,
https://doi.org/10.1016/j.icarus.2017.04.028, 2017.
Washenfelder, R. A., Flores, J. M., Brock, C. A., Brown, S. S., and Rudich,
Y.: Broadband measurements of aerosol extinction in the ultraviolet spectral
region, Atmos. Meas. Tech., 6, 861–877,
https://doi.org/10.5194/amt-6-861-2013, 2013.
Wei, Y., Ma, L., Cao, T., Zhang, Q., Wu, J., Buseck, P. R., and Thompson, J.
E.: Light Scattering and Extinction Measurements Combined with Laser-Induced
Incandescence for the Real-Time Determination of Soot Mass Absorption Cross
Section, Anal. Chem., 85, 9181–9188, https://doi.org/10.1021/ac401901b, 2013.
Weingartner, E., Saathoff, H., Schnaiter, M., Streit, N., Bitnar, B., and
Baltensperger, U.: Absorption of light by soot particles: Determination of
the absorption coefficient by means of aethalometers, J. Aerosol Sci., 34,
1445–1463, https://doi.org/10.1016/S0021-8502(03)00359-8, 2003.
Zangmeister, C. D. and Radney, J. G.: NIST interlaboratory study of aerosol
absorption measurements using photoacoustic spectroscopy, Tech. Note 1989,
https://doi.org/10.6028/NIST.TN.1989, 2018.
Short summary
A new technique for calibrating photo-acoustic absorption spectrometers (PASs) has been developed utilizing polydisperse, highly-absorbing aerosol and a commercially available instrument that measures particle extinction and scattering. This is the first calibration technique for multi-pass PAS instruments that does not require particles with known refractive index or reactive gases. Three substances were tested: Aquadag, Regal Black, and Nigrosin. All calibrations were consistent to within 5 %.
A new technique for calibrating photo-acoustic absorption spectrometers (PASs) has been...
