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.
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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
Deriving the hygroscopicity of ambient particles using low-cost optical particle counters
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
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
A reel-down instrument system for profile measurements of water vapor, temperature, clouds, and aerosol beneath constant-altitude scientific balloons
Airborne extractive electrospray mass spectrometry measurements of the chemical composition of organic aerosol
A semicontinuous study on the ecotoxicity of atmospheric particles using a versatile aerosol concentration enrichment system (VACES): development and field characterization
A novel rocket-borne ion mass spectrometer with large mass range: instrument description and first-flight results
Detailed characterization of the CAPS single-scattering albedo monitor (CAPS PMssa) as a field-deployable instrument for measuring aerosol light absorption with the extinction-minus-scattering method
New in situ aerosol hyperspectral optical measurements over 300–700 nm – Part 1: Spectral Aerosol Extinction (SpEx) instrument field validation during the KORUS-OC cruise
New in situ aerosol hyperspectral optical measurements over 300–700 nm – Part 2: Extinction, total absorption, water- and methanol-soluble absorption observed during the KORUS-OC cruise
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
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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.
Darren Cheng, Stavros Amanatidis, Gregory S. Lewis, and Coty N. Jen
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-157, https://doi.org/10.5194/amt-2024-157, 2024
Revised manuscript accepted for AMT
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This study describes a new instrument, the Condensation Particle Counter 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 in Pittsburgh, PA.
Ivonne Trebs, Céline Lett, Andreas Krein, Erika Matsumoto Kawaguchi, and Jürgen Junk
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-134, https://doi.org/10.5194/amt-2024-134, 2024
Revised manuscript accepted for AMT
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This study explores the effectiveness of the Horiba PX-375 monitor for analyzing 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.
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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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.
Lars E. Kalnajs, Sean M. Davis, J. Douglas Goetz, Terry Deshler, Sergey Khaykin, Alex St. Clair, Albert Hertzog, Jerome Bordereau, and Alexey Lykov
Atmos. Meas. Tech., 14, 2635–2648, https://doi.org/10.5194/amt-14-2635-2021, https://doi.org/10.5194/amt-14-2635-2021, 2021
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This work introduces a novel instrument system for high-resolution atmospheric profiling, which lowers and retracts a suspended instrument package beneath drifting long-duration balloons. During a 100 d circumtropical flight, the instrument collected over a hundred 2 km profiles of temperature, water vapor, clouds, and aerosol at 1 m resolution, yielding unprecedented geographic sampling and vertical resolution measurements of the tropical tropopause layer.
Demetrios Pagonis, Pedro Campuzano-Jost, Hongyu Guo, Douglas A. Day, Melinda K. Schueneman, Wyatt L. Brown, Benjamin A. Nault, Harald Stark, Kyla Siemens, Alex Laskin, Felix Piel, Laura Tomsche, Armin Wisthaler, Matthew M. Coggon, Georgios I. Gkatzelis, Hannah S. Halliday, Jordan E. Krechmer, Richard H. Moore, David S. Thomson, Carsten Warneke, Elizabeth B. Wiggins, and Jose L. Jimenez
Atmos. Meas. Tech., 14, 1545–1559, https://doi.org/10.5194/amt-14-1545-2021, https://doi.org/10.5194/amt-14-1545-2021, 2021
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We describe the airborne deployment of an extractive electrospray time-of-flight mass spectrometer (EESI-MS). The instrument provides a quantitative 1 Hz measurement of the chemical composition of organic aerosol up to altitudes of
7 km, with single-compound detection limits as low as 50 ng per standard cubic meter.
Xiaona Shang, Ling Li, Xinlian Zhang, Huihui Kang, Guodong Sui, Gehui Wang, Xingnan Ye, Hang Xiao, and Jianmin Chen
Atmos. Meas. Tech., 14, 1037–1045, https://doi.org/10.5194/amt-14-1037-2021, https://doi.org/10.5194/amt-14-1037-2021, 2021
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Oxidative stress can be used to evaluate not only adverse health effects but also adverse ecological effects. However, little research uses eco-toxicological assay to assess the risks posed by particle matter to non-human biomes. One important reason might be that the concentration of toxic components of atmospheric particles is far below the high detection limit of eco-toxic measurement. To solve the rapid detection problem, we extended a VACES for ecotoxicity aerosol measurement.
Joan Stude, Heinfried Aufmhoff, Hans Schlager, Markus Rapp, Frank Arnold, and Boris Strelnikov
Atmos. Meas. Tech., 14, 983–993, https://doi.org/10.5194/amt-14-983-2021, https://doi.org/10.5194/amt-14-983-2021, 2021
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In this paper we describe the instrument ROMARA and show data from the first flight on a research rocket.
On the way through the atmosphere, the instrument detects positive and negative, natural occurring ions before returning back to ground.
ROMARA was successfully launched together with other instruments into a special radar echo.
We detected typical, light ions of positive and negative charge and heavy negative ions, but no heavy positive ions.
Rob L. Modini, Joel C. Corbin, Benjamin T. Brem, Martin Irwin, Michele Bertò, Rosaria E. Pileci, Prodromos Fetfatzis, Kostas Eleftheriadis, Bas Henzing, Marcel M. Moerman, Fengshan Liu, Thomas Müller, and Martin Gysel-Beer
Atmos. Meas. Tech., 14, 819–851, https://doi.org/10.5194/amt-14-819-2021, https://doi.org/10.5194/amt-14-819-2021, 2021
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Extinction-minus-scattering is an important method for measuring aerosol light absorption, but its application in the field presents a number of challenges. A recently developed instrument based on this method – the CAPS PMssa – has the potential to overcome some of these challenges. We present a compilation of theory, lab measurements, and field examples to characterize this instrument and show the conditions under which it can deliver reliable absorption measurements for atmospheric aerosols.
Carolyn E. Jordan, Ryan M. Stauffer, Brian T. Lamb, Charles H. Hudgins, Kenneth L. Thornhill, Gregory L. Schuster, Richard H. Moore, Ewan C. Crosbie, Edward L. Winstead, Bruce E. Anderson, Robert F. Martin, Michael A. Shook, Luke D. Ziemba, Andreas J. Beyersdorf, Claire E. Robinson, Chelsea A. Corr, and Maria A. Tzortziou
Atmos. Meas. Tech., 14, 695–713, https://doi.org/10.5194/amt-14-695-2021, https://doi.org/10.5194/amt-14-695-2021, 2021
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First field data from a custom-built in situ instrument measuring hyperspectral (300–700 nm, 0.8 nm resolution) ambient atmospheric aerosol extinction are presented. The advantage of this capability is that it can be directly linked to other in situ techniques that measure physical and chemical properties of atmospheric aerosols. Second-order polynomials provided a better fit to the data than traditional power law fits, yielding greater discrimination among distinct ambient aerosol populations.
Carolyn E. Jordan, Ryan M. Stauffer, Brian T. Lamb, Michael Novak, Antonio Mannino, Ewan C. Crosbie, Gregory L. Schuster, Richard H. Moore, Charles H. Hudgins, Kenneth L. Thornhill, Edward L. Winstead, Bruce E. Anderson, Robert F. Martin, Michael A. Shook, Luke D. Ziemba, Andreas J. Beyersdorf, Claire E. Robinson, Chelsea A. Corr, and Maria A. Tzortziou
Atmos. Meas. Tech., 14, 715–736, https://doi.org/10.5194/amt-14-715-2021, https://doi.org/10.5194/amt-14-715-2021, 2021
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In situ measurements of ambient atmospheric aerosol hyperspectral (300–700 nm) optical properties (extinction, total absorption, water- and methanol-soluble absorption) were observed around the Korean peninsula. Such in situ observations provide a direct link between ambient aerosol optical properties and their physicochemical properties. The benefit of hyperspectral measurements is evident as simple mathematical functions could not fully capture the observed spectral detail of ambient aerosols.
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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...