Articles | Volume 11, issue 3
https://doi.org/10.5194/amt-11-1707-2018
© Author(s) 2018. 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-11-1707-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
27 Mar 2018
Research article |
| 27 Mar 2018
| 27 Mar 2018
A new photometric ozone reference in the Huggins bands: the absolute ozone absorption cross section at the 325 nm HeCd laser wavelength
Christof Janssen
CORRESPONDING AUTHOR
Sorbonne Université, Observatoire de Paris, Université PSL, CNRS, Laboratoire
d'Etudes du Rayonnement et de la Matière en Astrophysique
et Atmosphères, LERMA-IPSL, 75005 Paris, France
Hadj Elandaloussi
Sorbonne Université, Observatoire de Paris, Université PSL, CNRS, Laboratoire
d'Etudes du Rayonnement et de la Matière en Astrophysique
et Atmosphères, LERMA-IPSL, 75005 Paris, France
Julian Gröbner
Physikalisches
Meteorologisches Observatorium Davos, World Radiation Center, Davos Dorf,
Switzerland
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Antonio Fernando Almansa, África Barreto, Natalia Kouremeti, Ramiro González, Akriti Masoom, Carlos Toledano, Julian Gröbner, Rosa Delia García, Yenny González, Stelios Kazadzis, Stéphane Victori, Óscar Álvarez, Fabrice Maupin, Virgilio Carreño, Victoria Eugenia Cachorro, and Emilio Cuevas
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Óscar Alvárez, África Barreto, Omaira E. García, Frank Hase, Rosa D. García, Julian Gröbner, Sergio F. León-Luis, Eliezer Sepúlveda, Virgilio Carreño, Antonio Alcántara, Ramón Ramos, A. Fernando Almansa, Stelios Kazadzis, Noémie Taquet, Carlos Toledano, and Emilio Cuevas
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In this work, we have extended the capabilities of a portable Fourier transform infrared (FTIR) instrument, which was originally designed to provide high-quality greenhouse gas monitoring within COCCON (COllaborative Carbon Column Observing Network). The extension allows the spectrometer to now also provide coincidentally column-integrated aerosol information. This addition of a reference instrument to a global network will be utilised to enhance our understanding of atmospheric chemistry.
Verena Schenzinger, Axel Kreuter, Barbara Klotz, Michael Schwarzmann, and Julian Gröbner
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Revised manuscript not accepted
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Julian Gröbner, Natalia Kouremeti, Gregor Hülsen, Ralf Zuber, Mario Ribnitzky, Saulius Nevas, Peter Sperfeld, Kerstin Schwind, Philipp Schneider, Stelios Kazadzis, África Barreto, Tom Gardiner, Kavitha Mottungan, David Medland, and Marc Coleman
Atmos. Meas. Tech., 16, 4667–4680, https://doi.org/10.5194/amt-16-4667-2023, https://doi.org/10.5194/amt-16-4667-2023, 2023
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Spectral solar irradiance measurements traceable to the International System of Units (SI) allow for intercomparability between instruments and for their validation according to metrological standards. Here we also validate and reduce the uncertainties of the top-of-atmosphere TSIS-1 Hybrid Solar Reference Spectrum (HSRS). The management of large networks, e.g. AERONET or GAW-PFR, will benefit from reducing logistical overhead, improving their resilience and achieving metrological traceability.
Luca Egli, Julian Gröbner, Herbert Schill, and Eliane Maillard Barras
Atmos. Meas. Tech., 16, 2889–2902, https://doi.org/10.5194/amt-16-2889-2023, https://doi.org/10.5194/amt-16-2889-2023, 2023
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This paper introduces a new method to retrieve total column ozone with spectral ground-based measurements from a novel array spectroradiometer. Total column ozone estimates using the small, cost-effective, and robust instrument and the new retrieval method are compared with other co-located total column ozone instruments. The comparison shows that the new system performs similarly to other well-established instruments, which require substantially more maintenance than the system introduced here.
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Panagiotis G. Kosmopoulos, Stelios Kazadzis, Alois W. Schmalwieser, Panagiotis I. Raptis, Kyriakoula Papachristopoulou, Ilias Fountoulakis, Akriti Masoom, Alkiviadis F. Bais, Julia Bilbao, Mario Blumthaler, Axel Kreuter, Anna Maria Siani, Kostas Eleftheratos, Chrysanthi Topaloglou, Julian Gröbner, Bjørn Johnsen, Tove M. Svendby, Jose Manuel Vilaplana, Lionel Doppler, Ann R. Webb, Marina Khazova, Hugo De Backer, Anu Heikkilä, Kaisa Lakkala, Janusz Jaroslawski, Charikleia Meleti, Henri Diémoz, Gregor Hülsen, Barbara Klotz, John Rimmer, and Charalampos Kontoes
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Ralf Zuber, Ulf Köhler, Luca Egli, Mario Ribnitzky, Wolfgang Steinbrecht, and Julian Gröbner
Atmos. Meas. Tech., 14, 4915–4928, https://doi.org/10.5194/amt-14-4915-2021, https://doi.org/10.5194/amt-14-4915-2021, 2021
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We validated two BTS-based systems in a longer-term TOC analysis in the 2019/2020 campaign at Hohenpeißenberg and Davos. The results showed a deviation of the BTS-Solar to Brewers of < 0.1 % with a k = 2 of < 1.5 %. Koherent showed a deviation of 1.7 % with a k = 2 of 2.7 %. Resultingly, the BTS-Solar performance is comparable to Brewers in Hohenpeißenberg. Koherent shows a seasonal variation in Davos due to the sensitivity of its TOC retrieval algorithm to stratospheric temperature.
Marek Šmíd, Geiland Porrovecchio, Jiří Tesař, Tim Burnitt, Luca Egli, Julian Grőbner, Petr Linduška, and Martin Staněk
Atmos. Meas. Tech., 14, 3573–3582, https://doi.org/10.5194/amt-14-3573-2021, https://doi.org/10.5194/amt-14-3573-2021, 2021
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We designed and developed a tuneable and portable radiation source (TuPS) to provide a reference wavelength scale, with a bandwidth of emitted radiation of 0.13 nm and uncertainty in wavelength of 0.02 nm. TuPS was successfully used for the in-field characterization of 14 Dobson spectrophotometers in campaigns in Europe. The line spread functions of Dobsons measured by TuPS in conjunction with the cross-sections from IUP improves the consistency between the Dobson and Brewer from 3 % to 1 %.
Julian Gröbner, Herbert Schill, Luca Egli, and René Stübi
Atmos. Meas. Tech., 14, 3319–3331, https://doi.org/10.5194/amt-14-3319-2021, https://doi.org/10.5194/amt-14-3319-2021, 2021
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The world's longest continuous total column ozone time series was initiated in 1926 at the Lichtklimatisches Observatorium (LKO), at Arosa, in the Swiss Alps. The measurements between Dobson and Brewer spectroradiometers have shown seasonal variations of the order of 2 %. The results of the study show that the consistency between the two instrument types can be significantly improved when the ozone cross-sections from Serdyuchenko et al. (2013) and the measured slit functions are used.
Kaisa Lakkala, Jukka Kujanpää, Colette Brogniez, Nicolas Henriot, Antti Arola, Margit Aun, Frédérique Auriol, Alkiviadis F. Bais, Germar Bernhard, Veerle De Bock, Maxime Catalfamo, Christine Deroo, Henri Diémoz, Luca Egli, Jean-Baptiste Forestier, Ilias Fountoulakis, Katerina Garane, Rosa Delia Garcia, Julian Gröbner, Seppo Hassinen, Anu Heikkilä, Stuart Henderson, Gregor Hülsen, Bjørn Johnsen, Niilo Kalakoski, Angelos Karanikolas, Tomi Karppinen, Kevin Lamy, Sergio F. León-Luis, Anders V. Lindfors, Jean-Marc Metzger, Fanny Minvielle, Harel B. Muskatel, Thierry Portafaix, Alberto Redondas, Ricardo Sanchez, Anna Maria Siani, Tove Svendby, and Johanna Tamminen
Atmos. Meas. Tech., 13, 6999–7024, https://doi.org/10.5194/amt-13-6999-2020, https://doi.org/10.5194/amt-13-6999-2020, 2020
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The TROPOspheric Monitoring Instrument (TROPOMI) onboard the Sentinel-5 Precursor (S5P) satellite was launched on 13 October 2017 to provide the atmospheric composition for atmosphere and climate research. Ground-based data from 25 sites located in Arctic, subarctic, temperate, equatorial and Antarctic
areas were used for the validation of the TROPOMI surface ultraviolet (UV) radiation product. For most sites 60 %–80 % of TROPOMI data was within ± 20 % of ground-based data.
Ilias Fountoulakis, Henri Diémoz, Anna Maria Siani, Gregor Hülsen, and Julian Gröbner
Earth Syst. Sci. Data, 12, 2787–2810, https://doi.org/10.5194/essd-12-2787-2020, https://doi.org/10.5194/essd-12-2787-2020, 2020
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In this study we discuss the procedures and the technical aspects which ensure the high quality of the measurements of the global solar ultraviolet (UV) irradiance performed by a Bentham spectroradiometer located at Aosta–Saint-Christophe (north-western Alps), Italy. This particular instrument is the reference for the Aosta Valley UV monitoring network, which is the first UV monitoring network in Italy. The final spectra constitute one of the most accurate datasets globally.
Christine Aebi, Julian Gröbner, Stelios Kazadzis, Laurent Vuilleumier, Antonis Gkikas, and Niklaus Kämpfer
Atmos. Meas. Tech., 13, 907–923, https://doi.org/10.5194/amt-13-907-2020, https://doi.org/10.5194/amt-13-907-2020, 2020
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Clouds are one of the largest sources of uncertainties in climate models. The current study estimates the cloud optical thickness (COT), the effective droplet radius and the single scattering albedo of stratus–altostratus and cirrus–cirrostratus clouds in Payerne, Switzerland, by combining ground- and satellite-based measurements and radiative transfer models. The estimated values are thereafter compared with data retrieved from other methods. The mean COT is distinct for different seasons.
Stephan Nyeki, Stefan Wacker, Christine Aebi, Julian Gröbner, Giovanni Martucci, and Laurent Vuilleumier
Atmos. Chem. Phys., 19, 13227–13241, https://doi.org/10.5194/acp-19-13227-2019, https://doi.org/10.5194/acp-19-13227-2019, 2019
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The trends of meteorological parameters and surface downward shortwave radiation (DSR) and downward longwave radiation (DLR) were analysed at four stations (between 370 and 3580 m a. s. l.) in Switzerland for the 1996–2015 period. Trends in DSR and DLR were positive during cloudy as well as clear conditions. The trend due to the influence of clouds decreased in magnitude, which implies a reduction in cloud cover and/or a change towards a different cloud type over the four Swiss sites.
Emilio Cuevas, Pedro Miguel Romero-Campos, Natalia Kouremeti, Stelios Kazadzis, Petri Räisänen, Rosa Delia García, Africa Barreto, Carmen Guirado-Fuentes, Ramón Ramos, Carlos Toledano, Fernando Almansa, and Julian Gröbner
Atmos. Meas. Tech., 12, 4309–4337, https://doi.org/10.5194/amt-12-4309-2019, https://doi.org/10.5194/amt-12-4309-2019, 2019
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A comprehensive comparison of more than 70 000 synchronous 1 min aerosol optical depth (AOD) data from 3 Global Atmosphere Watch precision filter radiometers (GAW-PFR) and 15 Aerosol Robotic Network Cimel radiometers (AERONET-Cimel) was performed for the four
nearwavelengths (380, 440, 500 and 870 nm) in the period 2005–2015. The goal of this study is to assess whether their long term AOD data are comparable and consistent.
Felix R. Vogel, Matthias Frey, Johannes Staufer, Frank Hase, Grégoire Broquet, Irène Xueref-Remy, Frédéric Chevallier, Philippe Ciais, Mahesh Kumar Sha, Pascale Chelin, Pascal Jeseck, Christof Janssen, Yao Té, Jochen Groß, Thomas Blumenstock, Qiansi Tu, and Johannes Orphal
Atmos. Chem. Phys., 19, 3271–3285, https://doi.org/10.5194/acp-19-3271-2019, https://doi.org/10.5194/acp-19-3271-2019, 2019
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Providing timely information on greenhouse gas emissions to stakeholders at sub-national scale is an emerging challenge and understanding urban CO2 levels is one key aspect. This study uses atmospheric observations of total column CO2 and compares them to numerical simulations to investigate CO2 levels in the Paris metropolitan area due to natural fluxes and anthropogenic emissions. Our measurements reveal the influence of locally added CO2, which our model is also able to predict.
Christine Aebi, Julian Gröbner, and Niklaus Kämpfer
Atmos. Meas. Tech., 11, 5549–5563, https://doi.org/10.5194/amt-11-5549-2018, https://doi.org/10.5194/amt-11-5549-2018, 2018
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A newly developed hemispherical thermal infrared cloud camera (IRCCAM) is presented. The IRCCAM allows automatic cloud detection during the day and at night-time. The cloud fraction determined from the IRCCAM is compared with the cloud fraction determined from other instruments over a time period of 2 years. The IRCCAM has an agreement of +/- 2 oktas cloud fraction in 90 % of the data compared to other instruments. There are no significant differences between seasons or different times of day.
Carlos Toledano, Ramiro González, David Fuertes, Emilio Cuevas, Thomas F. Eck, Stelios Kazadzis, Natalia Kouremeti, Julian Gröbner, Philippe Goloub, Luc Blarel, Roberto Román, África Barreto, Alberto Berjón, Brent N. Holben, and Victoria E. Cachorro
Atmos. Chem. Phys., 18, 14555–14567, https://doi.org/10.5194/acp-18-14555-2018, https://doi.org/10.5194/acp-18-14555-2018, 2018
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Most of the ground-based radiometric networks have their reference instruments and/or calibrate them at Mauna Loa or Izaña. The suitability of these high-mountain stations for absolute radiometric calibrations is investigated with the support of 20 years of first-class Sun photometer data from the AERONET and GAW-PFR networks. We analyze the number of calibration days at each site in a climatological sense and investigate the uncertainty of the calibrations based on long-term statistics.
Kaisa Lakkala, Antti Arola, Julian Gröbner, Sergio Fabian León-Luis, Alberto Redondas, Stelios Kazadzis, Tomi Karppinen, Juha Matti Karhu, Luca Egli, Anu Heikkilä, Tapani Koskela, Antonio Serrano, and José Manuel Vilaplana
Atmos. Meas. Tech., 11, 5167–5180, https://doi.org/10.5194/amt-11-5167-2018, https://doi.org/10.5194/amt-11-5167-2018, 2018
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The performance of the cosine error correction method for correcting spectral UV measurements of the Brewer spectroradiometer was studied. The correction depends on the sky radiation distribution, which can change during one spectral scan. The results showed that the correction varied between 4 and 14 %, and that the relative differences between the reference and the Brewer diminished by 10 %. The method is applicable to other instruments as long as the required input parameters are available.
Alberto Redondas, Virgilio Carreño, Sergio F. León-Luis, Bentorey Hernández-Cruz, Javier López-Solano, Juan J. Rodriguez-Franco, José M. Vilaplana, Julian Gröbner, John Rimmer, Alkiviadis F. Bais, Vladimir Savastiouk, Juan R. Moreta, Lamine Boulkelia, Nis Jepsen, Keith M. Wilson, Vadim Shirotov, and Tomi Karppinen
Atmos. Chem. Phys., 18, 9441–9455, https://doi.org/10.5194/acp-18-9441-2018, https://doi.org/10.5194/acp-18-9441-2018, 2018
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This work shows an overview of the total ozone comparison of the Brewer instrument during the 10th RBCC-E campaign in a joint effort with the EUBREWNET COST 1207 action. The status of the network after 2 years of calibration shows 16 out of the 21 participating Brewer instruments (76 %) agreed within better than ±1 %, and 10 instruments (50 %) agreed within better than ±0.5 %. After applying the final calibration and the stray light correction all working instruments agreed at the ±0.5 % level.
Anna Vaskuri, Petri Kärhä, Luca Egli, Julian Gröbner, and Erkki Ikonen
Atmos. Meas. Tech., 11, 3595–3610, https://doi.org/10.5194/amt-11-3595-2018, https://doi.org/10.5194/amt-11-3595-2018, 2018
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In this work, we introduce a Monte Carlo uncertainty analysis that takes into account possible systematic spectral deviations in the atmospheric full spectrum ozone retrieval method. Accounting for possible systematic spectral deviations in the spectral data is important since they produce larger total ozone column uncertainties than uncorrelated noise-like variations that traditional uncertainty estimations predict.
Rosa Delia García, Africa Barreto, Emilio Cuevas, Julian Gröbner, Omaira Elena García, Angel Gómez-Peláez, Pedro Miguel Romero-Campos, Alberto Redondas, Victoria Eugenia Cachorro, and Ramon Ramos
Geosci. Model Dev., 11, 2139–2152, https://doi.org/10.5194/gmd-11-2139-2018, https://doi.org/10.5194/gmd-11-2139-2018, 2018
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A 7-year comparison study between measured and simulated longwave
downward radiation under cloud-free conditions has been performed at BSRN Izaña. Results show an excellent agreement with a mean bias (simulated–measured) less than 1.1 % and RMSE less than 1 %, which are within the instrumental error (2 %).
Daniela Meloni, Alcide di Sarra, Gérard Brogniez, Cyrielle Denjean, Lorenzo De Silvestri, Tatiana Di Iorio, Paola Formenti, José L. Gómez-Amo, Julian Gröbner, Natalia Kouremeti, Giuliano Liuzzi, Marc Mallet, Giandomenico Pace, and Damiano M. Sferlazzo
Atmos. Chem. Phys., 18, 4377–4401, https://doi.org/10.5194/acp-18-4377-2018, https://doi.org/10.5194/acp-18-4377-2018, 2018
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This study examines how different aerosol optical properties determine the dust longwave radiative effects at the surface, in the atmosphere and at the top of the atmosphere, based on the combination of remote sensing and in situ observations from the ground, from airborne sensors, and from space, by means of radiative transfer modelling. The closure experiment is based on longwave irradiances and spectral brightness temperatures measured during the 2013 ChArMEx–ADRIMED campaign at Lampedusa.
Javier López-Solano, Alberto Redondas, Thomas Carlund, Juan J. Rodriguez-Franco, Henri Diémoz, Sergio F. León-Luis, Bentorey Hernández-Cruz, Carmen Guirado-Fuentes, Natalia Kouremeti, Julian Gröbner, Stelios Kazadzis, Virgilio Carreño, Alberto Berjón, Daniel Santana-Díaz, Manuel Rodríguez-Valido, Veerle De Bock, Juan R. Moreta, John Rimmer, Andrew R. D. Smedley, Lamine Boulkelia, Nis Jepsen, Paul Eriksen, Alkiviadis F. Bais, Vadim Shirotov, José M. Vilaplana, Keith M. Wilson, and Tomi Karppinen
Atmos. Chem. Phys., 18, 3885–3902, https://doi.org/10.5194/acp-18-3885-2018, https://doi.org/10.5194/acp-18-3885-2018, 2018
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The European Brewer Network (EUBREWNET, COST Action ES1207) is comprised of close to 50 instruments and currently provides near-real-time ozone and UV data. Aerosols also play key role in the Earth–atmosphere system and introduce a large uncertainty into our understanding of climate change. In this work we describe and validate a method to incorporate the measurement of aerosols in EUBREWNET. We find that this Brewer network can provide reliable aerosol data across Europe in the UV range.
Stelios Kazadzis, Natalia Kouremeti, Henri Diémoz, Julian Gröbner, Bruce W. Forgan, Monica Campanelli, Victor Estellés, Kathleen Lantz, Joseph Michalsky, Thomas Carlund, Emilio Cuevas, Carlos Toledano, Ralf Becker, Stephan Nyeki, Panagiotis G. Kosmopoulos, Viktar Tatsiankou, Laurent Vuilleumier, Frederick M. Denn, Nozomu Ohkawara, Osamu Ijima, Philippe Goloub, Panagiotis I. Raptis, Michael Milner, Klaus Behrens, Africa Barreto, Giovanni Martucci, Emiel Hall, James Wendell, Bryan E. Fabbri, and Christoph Wehrli
Atmos. Chem. Phys., 18, 3185–3201, https://doi.org/10.5194/acp-18-3185-2018, https://doi.org/10.5194/acp-18-3185-2018, 2018
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Aerosol optical depth measured from ground-based sun photometers is the most important parameter for studying the changes in the Earth's radiation balance due to aerosols. Representatives for various sun photometer types belonging to individual institutions or international aerosol networks gather every 5 years, for 3 weeks, in Davos, Switzerland, in order to compare their aeorosol optical depth retrievals. This work presents the results of the latest (fourth) filter radiometer intercomparison.
Panagiotis-Ioannis Raptis, Stelios Kazadzis, Julian Gröbner, Natalia Kouremeti, Lionel Doppler, Ralf Becker, and Constantinos Helmis
Atmos. Meas. Tech., 11, 1143–1157, https://doi.org/10.5194/amt-11-1143-2018, https://doi.org/10.5194/amt-11-1143-2018, 2018
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The purpose of this work is to retrieve integrated water vapour using spectral measurements from Precision Solar Spectroradiometer (PSR). Two different approaches were developed one using single-channel direct sun irradiance measurements, and the second one integrating at a certain spectral region. The results of the spectral approach are closer to the retrievals of non-photometric techniques (GPS, microwave radiometer and radiosondes), suggesting this method provide more accurate IWV product.
Stelios Kazadzis, Natalia Kouremeti, Stephan Nyeki, Julian Gröbner, and Christoph Wehrli
Geosci. Instrum. Method. Data Syst., 7, 39–53, https://doi.org/10.5194/gi-7-39-2018, https://doi.org/10.5194/gi-7-39-2018, 2018
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The World Optical Depth Research Calibration Center (WORCC) has been established after the recommendations of WMO for calibration of aerosol optical depth (AOD) -related sun photometers. WORCC is mandated to initiate homogenization activities among different AOD networks and to run a network (GAW-PFR) of sun photometers. To calibrate such instruments aiming at low measurement uncertainties the quality assurance, quality control and a basic hierarchy have to be defined and followed.
Christine Aebi, Julian Gröbner, Niklaus Kämpfer, and Laurent Vuilleumier
Atmos. Meas. Tech., 10, 4587–4600, https://doi.org/10.5194/amt-10-4587-2017, https://doi.org/10.5194/amt-10-4587-2017, 2017
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The current study analyses the cloud radiative effect during the daytime depending on cloud fraction and cloud type at two stations in Switzerland over a time period of 3–5 years. Information about fractional cloud coverage and cloud type is retrieved from images taken by visible all-sky cameras. Cloud cover, cloud type and other atmospheric parameters have an influence on the magnitude of the longwave cloud effect as well as on the shortwave.
René Stübi, Herbert Schill, Jörg Klausen, Laurent Vuilleumier, Julian Gröbner, Luca Egli, and Dominique Ruffieux
Atmos. Meas. Tech., 10, 4479–4490, https://doi.org/10.5194/amt-10-4479-2017, https://doi.org/10.5194/amt-10-4479-2017, 2017
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Long-term measurement series are the pillars of all climate change analysis. The Arosa total ozone series is the world's longest record, starting in 1926. To secure the future of these measurements, it is foreseen to move the instruments in Davos. To ascertain that the series will not be affected by this change, a multiyear campaign of parallel measurements on both sites has been done. The analysis of these data is presented and it is concluded that no discernible difference can be identified.
Julian Gröbner, Ingo Kröger, Luca Egli, Gregor Hülsen, Stefan Riechelmann, and Peter Sperfeld
Atmos. Meas. Tech., 10, 3375–3383, https://doi.org/10.5194/amt-10-3375-2017, https://doi.org/10.5194/amt-10-3375-2017, 2017
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We have produced a benchmark high-resolution solar extraterrestrial spectrum from ground-based measurements of direct solar irradiance in the wavelength range 300 to 500 nm. This spectrum can be used for model calculations and for validating solar spectra measured in space. The metrological traceability of this solar spectrum to the International System of Units (SI) is assured by an unbroken chain of calibrations traceable to the primary spectral irradiance standard of PTB.
Stephan Nyeki, Stefan Wacker, Julian Gröbner, Wolfgang Finsterle, and Martin Wild
Atmos. Meas. Tech., 10, 3057–3071, https://doi.org/10.5194/amt-10-3057-2017, https://doi.org/10.5194/amt-10-3057-2017, 2017
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A large number of radiometers used to measure solar and terrestrial broadband radiation are traceable to World Standard Groups at PMOD/WRC in Davos, Switzerland. A small correction of each group may be required in the future, and this study examines the methods and implications of this on data sets collected at four remote baseline stations since the 1990s. The goal is to develop a better estimate of the solar and terrestrial radiation budget at the Earth's surface.
Thomas Carlund, Natalia Kouremeti, Stelios Kazadzis, and Julian Gröbner
Atmos. Meas. Tech., 10, 905–923, https://doi.org/10.5194/amt-10-905-2017, https://doi.org/10.5194/amt-10-905-2017, 2017
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Aerosols play an important role in atmospheric processes. Aerosol optical depth is the most common measure of columnar aerosol load. We present a sunphotometer called UVPFR that is able to measure aerosol optical depth in the ultraviolet range, including the calibration, characterization and validation of the instrument/measurements. The instrument will serve as a reference on the intercalibration of Brewer spectrophotometers that are also able to measure aerosol optical depth in the UV region.
Christos S. Zerefos, Kostas Eleftheratos, John Kapsomenakis, Stavros Solomos, Antje Inness, Dimitris Balis, Alberto Redondas, Henk Eskes, Marc Allaart, Vassilis Amiridis, Arne Dahlback, Veerle De Bock, Henri Diémoz, Ronny Engelmann, Paul Eriksen, Vitali Fioletov, Julian Gröbner, Anu Heikkilä, Irina Petropavlovskikh, Janusz Jarosławski, Weine Josefsson, Tomi Karppinen, Ulf Köhler, Charoula Meleti, Christos Repapis, John Rimmer, Vladimir Savinykh, Vadim Shirotov, Anna Maria Siani, Andrew R. D. Smedley, Martin Stanek, and René Stübi
Atmos. Chem. Phys., 17, 551–574, https://doi.org/10.5194/acp-17-551-2017, https://doi.org/10.5194/acp-17-551-2017, 2017
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The paper makes a convincing case that the Brewer network is capable of detecting enhanced SO2 columns, as observed, e.g., after volcanic eruptions. For this reason, large volcanic eruptions of the past decade have been used to detect and forecast SO2 plumes of volcanic origin using the Brewer and other ground-based networks, aided by satellite, trajectory analysis calculations and modelling.
Bastiaan Jonkheid, Thomas Röckmann, Norbert Glatthor, Christof Janssen, Gabriele Stiller, and Thomas von Clarmann
Atmos. Meas. Tech., 9, 6069–6079, https://doi.org/10.5194/amt-9-6069-2016, https://doi.org/10.5194/amt-9-6069-2016, 2016
Yao Té, Pascal Jeseck, Bruno Franco, Emmanuel Mahieu, Nicholas Jones, Clare Paton-Walsh, David W. T. Griffith, Rebecca R. Buchholz, Juliette Hadji-Lazaro, Daniel Hurtmans, and Christof Janssen
Atmos. Chem. Phys., 16, 10911–10925, https://doi.org/10.5194/acp-16-10911-2016, https://doi.org/10.5194/acp-16-10911-2016, 2016
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This paper studies the seasonal variation of surface and column CO at three different sites (Paris, Jungfraujoch and Wollongong), with an emphasis on establishing a link between the CO vertical distribution and the nature of CO emission sources. We find the first evidence of a time lag between surface and free tropospheric CO seasonal variations in the Northern Hemisphere.
Luca Egli, Julian Gröbner, Gregor Hülsen, Luciano Bachmann, Mario Blumthaler, Jimmy Dubard, Marina Khazova, Richard Kift, Kees Hoogendijk, Antonio Serrano, Andrew Smedley, and José-Manuel Vilaplana
Atmos. Meas. Tech., 9, 1553–1567, https://doi.org/10.5194/amt-9-1553-2016, https://doi.org/10.5194/amt-9-1553-2016, 2016
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Array spectroradiometers are small, light, robust and cost-effective instruments, and are increasingly used for atmospheric measurements. The quality of array spectroradiometers is assessed for the reliable quantification of ultraviolet radiation (UV) in order to monitor the exposure of UV radiation to human health. The study shows that reliable UV measurements with these instruments are limited for observations around noon and show large biases in the morning and evening.
África Barreto, Emilio Cuevas, María-José Granados-Muñoz, Lucas Alados-Arboledas, Pedro M. Romero, Julian Gröbner, Natalia Kouremeti, Antonio F. Almansa, Tom Stone, Carlos Toledano, Roberto Román, Mikhail Sorokin, Brent Holben, Marius Canini, and Margarita Yela
Atmos. Meas. Tech., 9, 631–654, https://doi.org/10.5194/amt-9-631-2016, https://doi.org/10.5194/amt-9-631-2016, 2016
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This paper presents the new photometer CE318-T, able to perform daytime and
night-time photometric measurements using the sun and the moon as light
sources. This new device permits a complete cycle of diurnal aerosol and water vapour measurements to be extracted, valuable to enhance atmospheric monitoring. We have also highlighted the ability of this new device to capture short-term atmospheric variations, critical for climate studies.
M. Lothon, F. Lohou, D. Pino, F. Couvreux, E. R. Pardyjak, J. Reuder, J. Vilà-Guerau de Arellano, P Durand, O. Hartogensis, D. Legain, P. Augustin, B. Gioli, D. H. Lenschow, I. Faloona, C. Yagüe, D. C. Alexander, W. M. Angevine, E Bargain, J. Barrié, E. Bazile, Y. Bezombes, E. Blay-Carreras, A. van de Boer, J. L. Boichard, A. Bourdon, A. Butet, B. Campistron, O. de Coster, J. Cuxart, A. Dabas, C. Darbieu, K. Deboudt, H. Delbarre, S. Derrien, P. Flament, M. Fourmentin, A. Garai, F. Gibert, A. Graf, J. Groebner, F. Guichard, M. A. Jiménez, M. Jonassen, A. van den Kroonenberg, V. Magliulo, S. Martin, D. Martinez, L. Mastrorillo, A. F. Moene, F. Molinos, E. Moulin, H. P. Pietersen, B. Piguet, E. Pique, C. Román-Cascón, C. Rufin-Soler, F. Saïd, M. Sastre-Marugán, Y. Seity, G. J. Steeneveld, P. Toscano, O. Traullé, D. Tzanos, S. Wacker, N. Wildmann, and A. Zaldei
Atmos. Chem. Phys., 14, 10931–10960, https://doi.org/10.5194/acp-14-10931-2014, https://doi.org/10.5194/acp-14-10931-2014, 2014
S. Kazadzis, I. Veselovskii, V. Amiridis, J. Gröbner, A. Suvorina, S. Nyeki, E. Gerasopoulos, N. Kouremeti, M. Taylor, A. Tsekeri, and C. Wehrli
Atmos. Meas. Tech., 7, 2013–2025, https://doi.org/10.5194/amt-7-2013-2014, https://doi.org/10.5194/amt-7-2013-2014, 2014
A. Stenke, C. R. Hoyle, B. Luo, E. Rozanov, J. Gröbner, L. Maag, S. Brönnimann, and T. Peter
Atmos. Chem. Phys., 13, 9713–9729, https://doi.org/10.5194/acp-13-9713-2013, https://doi.org/10.5194/acp-13-9713-2013, 2013
T. Egorova, E. Rozanov, J. Gröbner, M. Hauser, and W. Schmutz
Atmos. Chem. Phys., 13, 3811–3823, https://doi.org/10.5194/acp-13-3811-2013, https://doi.org/10.5194/acp-13-3811-2013, 2013
Related subject area
Subject: Gases | Technique: Laboratory Measurement | Topic: Instruments and Platforms
A high-accuracy dynamic dilution method for generating reference gas mixtures of carbonyl sulfide at sub-nanomole-per-mole levels for long-term atmospheric observation
Optimizing the iodide-adduct chemical ionization mass spectrometry (CIMS) quantitative method for toluene oxidation intermediates: experimental insights into functional-group differences
Characterization of a new Teflon chamber and on-line analysis of isomeric multifunctional photooxidation products
A versatile water vapor generation module for vapor isotope calibration and liquid isotope measurements
Extraction, purification, and clumped isotope analysis of methane (Δ13CDH3 and Δ12CD2H2) from sources and the atmosphere
Response of protonated, adduct, and fragmented ions in Vocus proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS)
Evaluation of a reduced pressure chemical ion reactor utilizing adduct ionization for the detection of gaseous organic and inorganic species
Absorption of volatile organic compounds (VOCs) by polymer tubing: implications for indoor air and use as a simple gas-phase volatility separation technique
A flexible device to produce a gas stream with a precisely controlled water vapour mixing ratio and isotope composition based on microdrop dispensing technology
Revision of an open-split-based dual-inlet system for elemental and isotope ratio mass spectrometers with a focus on clumped-isotope measurements
Characterisation of gaseous iodine species detection using the multi-scheme chemical ionisation inlet 2 with bromide and nitrate chemical ionisation methods
A novel inlet for enriching concentrations of reactive organic gases in low sampling flows
Ammonium CI-Orbitrap: a tool for characterizing the reactivity of oxygenated organic molecules
Characterizing the automatic radon flux transfer standard system Autoflux: laboratory calibration and field experiments
Water vapor stable isotope memory effects of common tubing materials
Influence of ozone and humidity on PTR-MS and GC-MS VOC measurements with and without a Na2S2O3 ozone scrubber
Laser-induced sublimation extraction for centimeter-resolution multi-species greenhouse gas analysis on ice cores
Ozone reactivity measurement of biogenic volatile organic compound emissions
Comparison of two photolytic calibration methods for nitrous acid
Measurement of enantiomer percentages for five monoterpenes from six conifer species by cartridge-tube-based passive sampling adsorption–thermal desorption (ps-ATD)
Identification, monitoring, and reaction kinetics of reactive trace species using time-resolved mid-infrared quantum cascade laser absorption spectroscopy: development, characterisation, and initial results for the CH2OO Criegee intermediate
Air pollution monitoring: development of ammonia (NH3) dynamic reference gas mixtures at nanomoles per mole levels to improve the lack of traceability of measurements
Formaldehyde and glyoxal measurement deploying a selected ion flow tube mass spectrometer (SIFT-MS)
Fragmentation inside proton-transfer-reaction-based mass spectrometers limits the detection of ROOR and ROOH peroxides
MULTICHARME: a modified Chernin-type multi-pass cell designed for IR and THz long-path absorption measurements in the CHARME atmospheric simulation chamber
Silicone tube humidity generator
A source for the continuous generation of pure and quantifiable HONO mixtures
Photochemical method for removing methane interference for improved gas analysis
A simulation chamber for absorption spectroscopy in planetary atmospheres
An automated system for trace gas flux measurements from plant foliage and other plant compartments
Simultaneous measurement of δ13C, δ18O and δ17O of atmospheric CO2 – performance assessment of a dual-laser absorption spectrometer
Measurement of iodine species and sulfuric acid using bromide chemical ionization mass spectrometers
A method for resolving changes in atmospheric He ∕ N2 as an indicator of fossil fuel extraction and stratospheric circulation
Application of chemical derivatization techniques combined with chemical ionization mass spectrometry to detect stabilized Criegee intermediates and peroxy radicals in the gas phase
Atomic emission detector with gas chromatographic separation and cryogenic pre-concentration (CryoTrap–GC–AED) for atmospheric trace gas measurements
New technique for high-precision, simultaneous measurements of CH4, N2O and CO2 concentrations; isotopic and elemental ratios of N2, O2 and Ar; and total air content in ice cores by wet extraction
High-precision laser spectrometer for multiple greenhouse gas analysis in 1 mL air from ice core samples
A thermal-dissociation–cavity ring-down spectrometer (TD-CRDS) for the detection of organic nitrates in gas and particle phases
Interference from alkenes in chemiluminescent NOx measurements
Calibration of an airborne HOx instrument using the All Pressure Altitude-based Calibrator for HOx Experimentation (APACHE)
Measurement of ammonia, amines and iodine compounds using protonated water cluster chemical ionization mass spectrometry
An instrument for in situ measurement of total ozone reactivity
Portable calibrator for NO based on the photolysis of N2O and a combined NO2∕NO∕O3 source for field calibrations of air pollution monitors
A new instrument for time-resolved measurement of HO2 radicals
Investigation of adsorption and desorption behavior of small-volume cylinders and its relevance for atmospheric trace gas analysis
Towards an understanding of surface effects: testing of various materials in a small volume measurement chamber and its relevance for atmospheric trace gas analysis
Stability of halocarbons in air samples stored in stainless- steel canisters
High-precision atmospheric oxygen measurement comparisons between a newly built CRDS analyzer and existing measurement techniques
Characterisation of the transfer of cluster ions through an atmospheric pressure interface time-of-flight mass spectrometer with hexapole ion guides
Addition of fast gas chromatography to selected ion flow tube mass spectrometry for analysis of individual monoterpenes in mixtures
Hideki Nara, Takuya Saito, Taku Umezawa, and Yasunori Tohjima
Atmos. Meas. Tech., 17, 5187–5200, https://doi.org/10.5194/amt-17-5187-2024, https://doi.org/10.5194/amt-17-5187-2024, 2024
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We have developed a high-accuracy dynamic dilution system for generating reference gas mixtures containing carbonyl sulfide (COS). Although COS at ambient levels generally has poor storage stability, our approach involves the dilution of a gas mixture containing micromole-per-mole levels of COS, the stability of which was validated for more than 1 decade. The developed system has excellent dilution performance and will facilitate accurate instrumental calibration for atmospheric COS observation.
Mengdi Song, Shuyu He, Xin Li, Ying Liu, Shengrong Lou, Sihua Lu, Limin Zeng, and Yuanhang Zhang
Atmos. Meas. Tech., 17, 5113–5127, https://doi.org/10.5194/amt-17-5113-2024, https://doi.org/10.5194/amt-17-5113-2024, 2024
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We introduce detailed and improved quantitation and semi-quantitation methods of iodide-adduct time-of-flight chemical ionization mass spectrometry (I-CIMS) to measure toluene oxidation intermediates. We assess the experimental sensitivity of various functional group species and their binding energy with iodide ions in I-CIMS. A novel classification approach was introduced to significantly enhance the accuracy of semi-quantitative methods (improving R2 values from 0.52 to beyond 0.88).
Finja Löher, Esther Borrás, Amalia Muñoz, and Anke Christine Nölscher
Atmos. Meas. Tech., 17, 4553–4579, https://doi.org/10.5194/amt-17-4553-2024, https://doi.org/10.5194/amt-17-4553-2024, 2024
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We constructed and characterized a new indoor Teflon atmospheric simulation chamber. We evaluated wall losses, photolysis rates, and secondary reactions of multifunctional photooxidation products in the chamber. To measure these products on-line, we combined chromatographic and mass spectrometric analyses to obtain both isomeric information and a high temporal resolution. For method validation, we studied the formation yields of the main ring-retaining products of toluene.
Hans Christian Steen-Larsen and Daniele Zannoni
Atmos. Meas. Tech., 17, 4391–4409, https://doi.org/10.5194/amt-17-4391-2024, https://doi.org/10.5194/amt-17-4391-2024, 2024
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The water vapor generation module is completely scalable, allowing autonomous calibrations to use N standards and providing integration times only restricted by sample availability. We document improved reproducibility in 17O-excess liquid measurements. This module makes spectroscopy measurements comparable to mass spectrometry. We document that the vapor generation module can be used to analyze instrument performance and for vapor isotope calibration during field campaign measurements.
Malavika Sivan, Thomas Röckmann, Carina van der Veen, and Maria Elena Popa
Atmos. Meas. Tech., 17, 2687–2705, https://doi.org/10.5194/amt-17-2687-2024, https://doi.org/10.5194/amt-17-2687-2024, 2024
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We have set up a measurement system for methane-clumped isotopologues. We have built an extraction and purification system to extract pure methane for these measurements, for samples of various origins, including atmospheric air, for which we need to process about 1000 L of air for one measurement. We report here the technical setup for extraction and measurements, as well as the calibration, and we give an overview of the samples measured so far.
Fangbing Li, Dan Dan Huang, Linhui Tian, Bin Yuan, Wen Tan, Liang Zhu, Penglin Ye, Douglas Worsnop, Ka In Hoi, Kai Meng Mok, and Yong Jie Li
Atmos. Meas. Tech., 17, 2415–2427, https://doi.org/10.5194/amt-17-2415-2024, https://doi.org/10.5194/amt-17-2415-2024, 2024
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The responses of protonated, adduct, and fragmented ions of 21 volatile organic compounds (VOCs) were investigated with varying instrument settings and relative humidity (RH) in a Vocus proton-transfer-reaction mass spectrometer (PTR-MS). The protonated ions of most VOCs studied show < 15 % variation in sensitivity, except for some long-chain aldehydes. The relationship between sensitivity and PTR rate constant is complicated by the influences from ion transmission and protonated ion fraction.
Matthieu Riva, Veronika Pospisilova, Carla Frege, Sebastien Perrier, Priyanka Bansal, Spiro Jorga, Patrick Sturm, Joel Thornton, Urs Rohner, and Felipe Lopez-Hilfiker
EGUsphere, https://doi.org/10.5194/egusphere-2024-945, https://doi.org/10.5194/egusphere-2024-945, 2024
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We present a newly designed reduced-pressure chemical ionization reactor for the detection of gas phase organic and inorganic species. The system operates through the combined use of VUV ionization and photosensitizers to generate numerous adduct ionization schemes. As a result, it offers the ability to simultaneously measure a wide variety of organic and inorganic species in terms of compound volatility and functionality, while being largely independent of changes in the sample humidity.
Melissa A. Morris, Demetrios Pagonis, Douglas A. Day, Joost A. de Gouw, Paul J. Ziemann, and Jose L. Jimenez
Atmos. Meas. Tech., 17, 1545–1559, https://doi.org/10.5194/amt-17-1545-2024, https://doi.org/10.5194/amt-17-1545-2024, 2024
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Polymer absorption of volatile organic compounds (VOCs) is important to characterize for atmospheric sampling setups (as interactions cause sampling delays) and indoor air quality. Here we test different polymer materials and quantify their absorptive capacities through modeling. We found the main polymers in carpets to be highly absorptive, acting as large reservoirs for indoor pollution. We also demonstrated how polymer tubes can be used as a low-cost gas separation technique.
Harald Sodemann, Alena Dekhtyareva, Alvaro Fernandez, Andrew Seidl, and Jenny Maccali
Atmos. Meas. Tech., 16, 5181–5203, https://doi.org/10.5194/amt-16-5181-2023, https://doi.org/10.5194/amt-16-5181-2023, 2023
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We describe a device that allows one to produce a continuous stream of water vapour with a specified level of humidity. As a main innovation, we can mix waters with different water isotope composition. Through a series of tests we show that the performance characteristics of the device are in line with specifications. We present two laboratory applications where the device proves useful, first in characterizing instruments, and second for the analysis of water contained in stalagmites.
Stephan Räss, Peter Nyfeler, Paul Wheeler, Will Price, and Markus Christian Leuenberger
Atmos. Meas. Tech., 16, 4489–4505, https://doi.org/10.5194/amt-16-4489-2023, https://doi.org/10.5194/amt-16-4489-2023, 2023
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Due to technological advances clumped-isotope studies have gained importance in recent years. Typically, these studies are performed with high-resolution isotope ratio mass spectrometers (IRMSs) along with a changeover-valve-based dual-inlet system (DIS). We are taking a different approach, namely performing clumped-isotope measurements with a compact low-resolution IRMS with an open-split-based DIS. Currently, we are working with pure-oxygen gas for which we are providing a proof of concept.
Xu-Cheng He, Jiali Shen, Siddharth Iyer, Paxton Juuti, Jiangyi Zhang, Mrisha Koirala, Mikko M. Kytökari, Douglas R. Worsnop, Matti Rissanen, Markku Kulmala, Norbert M. Maier, Jyri Mikkilä, Mikko Sipilä, and Juha Kangasluoma
Atmos. Meas. Tech., 16, 4461–4487, https://doi.org/10.5194/amt-16-4461-2023, https://doi.org/10.5194/amt-16-4461-2023, 2023
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In this study, the upgraded multi-scheme chemical ionisation inlet 2 is presented. Sulfuric acid, hypoiodous acid, iodine, sulfur dioxide, and hydroperoxyl radicals are calibrated, and the improved ion optics allow us to detect sulfuric acid and iodine-containing molecules at as low as a few parts per quadrillion by volume. Additionally, we confirm the reliable detection of iodic acid using both the nitrate and bromide chemical ionisation methods under atmospherically relevant conditions.
Namrata Shanmukh Panji and Gabriel Isaacman-VanWertz
Atmos. Meas. Tech., 16, 4319–4330, https://doi.org/10.5194/amt-16-4319-2023, https://doi.org/10.5194/amt-16-4319-2023, 2023
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Measuring volatile organic compounds (VOCs) in the atmosphere is crucial for understanding air quality and environmental impact. Since these compounds are present in low concentrations, preconcentration of samples is often necessary for accurate detection. To address this issue, we have developed a novel inlet that uses selective permeation to concentrate organic gases in small sample flows. This device offers a promising approach for accurately detecting low levels of VOCs in the atmosphere.
Dandan Li, Dongyu Wang, Lucia Caudillo, Wiebke Scholz, Mingyi Wang, Sophie Tomaz, Guillaume Marie, Mihnea Surdu, Elias Eccli, Xianda Gong, Loic Gonzalez-Carracedo, Manuel Granzin, Joschka Pfeifer, Birte Rörup, Benjamin Schulze, Pekka Rantala, Sébastien Perrier, Armin Hansel, Joachim Curtius, Jasper Kirkby, Neil M. Donahue, Christian George, Imad El-Haddad, and Matthieu Riva
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2023-149, https://doi.org/10.5194/amt-2023-149, 2023
Revised manuscript accepted for AMT
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Due to various analytical challenges in measuring organic vapors, it remains challenging to identify and quantify organic molecules present in the atmosphere, Here, we explore the performance of the chemical ionization Orbitrap mass spectrometer (CI-Orbitrap) using ammonium ion chemistry. This study shows that ammonium ion-based chemistry associated with the high mass resolving power of the Orbitrap mass analyzer can measure almost all-inclusive compounds.
Claudia Grossi, Daniel Rabago, Scott Chambers, Carlos Sáinz, Roger Curcoll, Peter P. S. Otáhal, Eliška Fialová, Luis Quindos, and Arturo Vargas
Atmos. Meas. Tech., 16, 2655–2672, https://doi.org/10.5194/amt-16-2655-2023, https://doi.org/10.5194/amt-16-2655-2023, 2023
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The automatic and low-maintenance radon flux system Autoflux, completed with environmental soil and atmosphere sensors, has been theoretically and experimentally characterized and calibrated under laboratory conditions to be used as transfer standard for in situ measurements. It will offer for the first time long-term measurements to validate radon flux maps used by the climate and the radiation protection communities for assessing the radon gas emissions in the atmosphere.
Alexandra L. Meyer and Lisa R. Welp
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2023-56, https://doi.org/10.5194/amt-2023-56, 2023
Revised manuscript accepted for AMT
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Water molecules stick to air intake tubing wall surfaces and exchange with ambient vapor. This can slow signal change measurements. We tested whether material type affects this stickiness. Less stickiness would lead to an instrument seeing signal changes faster. We unexpectedly saw no difference in signal speed between material types. Water vapor stable isotope users can more confidently use plastic tubing and compare measurements across observation systems that used different tubing materials.
Lisa Ernle, Monika Akima Ringsdorf, and Jonathan Williams
Atmos. Meas. Tech., 16, 1179–1194, https://doi.org/10.5194/amt-16-1179-2023, https://doi.org/10.5194/amt-16-1179-2023, 2023
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Atmospheric ozone can induce artefacts in volatile organic compound measurements. Laboratory tests were made using GC-MS and PTR-MS aircraft systems under tropospheric and stratospheric conditions of humidity and ozone, with and without sodium thiosulfate filter scrubbers. Ozone in dry air produces some carbonyls and degrades alkenes. The scrubber lifetime depends on ozone concentration, flow rate and humidity. For the troposphere with scrubber, no significant artefacts were found over 14 d.
Lars Mächler, Daniel Baggenstos, Florian Krauss, Jochen Schmitt, Bernhard Bereiter, Remo Walther, Christoph Reinhard, Béla Tuzson, Lukas Emmenegger, and Hubertus Fischer
Atmos. Meas. Tech., 16, 355–372, https://doi.org/10.5194/amt-16-355-2023, https://doi.org/10.5194/amt-16-355-2023, 2023
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We present a new method to extract the gases from ice cores and measure their greenhouse gas composition. The ice is sublimated continuously with a near-infrared laser, releasing the gases, which are then analyzed on a laser absorption spectrometer. The main advantage over previous efforts is a low effective resolution of 1–2 cm. This capability is crucial for the analysis of highly thinned ice, as expected from ongoing drilling efforts to extend ice core history further back in time.
Detlev Helmig, Alex Guenther, Jacques Hueber, Ryan Daly, Wei Wang, Jeong-Hoo Park, Anssi Liikanen, and Arnaud P. Praplan
Atmos. Meas. Tech., 15, 5439–5454, https://doi.org/10.5194/amt-15-5439-2022, https://doi.org/10.5194/amt-15-5439-2022, 2022
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This research demonstrates a new method for determination of the chemical reactivity of volatile organic compounds that are emitted from the leaves and needles of trees. These measurements allow elucidating if and how much of these emissions and their associated reactivity are captured and quantified by currently applicable chemical analysis methods.
Andrew J. Lindsay and Ezra C. Wood
Atmos. Meas. Tech., 15, 5455–5464, https://doi.org/10.5194/amt-15-5455-2022, https://doi.org/10.5194/amt-15-5455-2022, 2022
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Nitrous acid (HONO) is an important source of the main atmospheric oxidant – the hydroxyl radical (OH). Advances in nitrous acid measurement techniques and calibration methods therefore improve our understanding of atmospheric oxidation processes. In this paper, we present two calibration methods based on photo-dissociating water vapor. These calibration methods are useful alternatives to conventional calibrations that involve a reacting hydrogen chloride vapor with sodium nitrite.
Ying Wang, Wentai Luo, Todd N. Rosenstiel, and James F. Pankow
Atmos. Meas. Tech., 15, 4651–4661, https://doi.org/10.5194/amt-15-4651-2022, https://doi.org/10.5194/amt-15-4651-2022, 2022
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A rapid, sensitive, and precise analytical method was developed for measuring the fractional amounts of the (−) and (+) forms of chiral enantiomeric forms of monoterpenes in air containing biogenic plant emissions. The method uses passive air sampling onto adsorption–thermal desorption (ATD) gas sampling cartridge tubes; this is followed by automatable thermal desorption onto a chiral gas chromatography (GC) column, followed by detection with mass spectrometry (MS).
Zara S. Mir, Matthew Jamieson, Nicholas R. Greenall, Paul W. Seakins, Mark A. Blitz, and Daniel Stone
Atmos. Meas. Tech., 15, 2875–2887, https://doi.org/10.5194/amt-15-2875-2022, https://doi.org/10.5194/amt-15-2875-2022, 2022
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In this work we describe the development and characterisation of an experiment using laser flash photolysis coupled with time-resolved mid-infrared (mid-IR) quantum cascade laser (QCL) absorption spectroscopy, with initial results reported for measurements of the infrared spectrum, kinetics, and product yields for the reaction of the CH2OO Criegee intermediate with SO2. This work has significance for the identification and measurement of reactive trace species in complex systems.
Tatiana Macé, Maitane Iturrate-Garcia, Céline Pascale, Bernhard Niederhauser, Sophie Vaslin-Reimann, and Christophe Sutour
Atmos. Meas. Tech., 15, 2703–2718, https://doi.org/10.5194/amt-15-2703-2022, https://doi.org/10.5194/amt-15-2703-2022, 2022
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LNE developed, with the company 2M PROCESS, a gas reference generator to dynamically generate NH3 reference gas mixtures in the air at very low fractions between 1 and 400 nmol/mol. The procedure defined by LNE for calibrating NH3 analyzers used for monitoring air quality guarantees relative expanded uncertainties lower than 2 % for this measurement range. The results of a comparison organized between METAS and LNE allowed the validation of LNE's reference generator and calibration procedure.
Antonia G. Zogka, Manolis N. Romanias, and Frederic Thevenet
Atmos. Meas. Tech., 15, 2001–2019, https://doi.org/10.5194/amt-15-2001-2022, https://doi.org/10.5194/amt-15-2001-2022, 2022
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We emphasize the application of SIFT-MS to detect two important atmospheric pollutants, i.e., formaldehyde (FM) and glyoxal (GL). FM and GL are secondary products formed by volatile organic compound oxidation in indoor and outdoor environments and play a key role in air quality and climate. We show that SIFT-MS is able to monitor these species selectively and in real time, overcoming the limitations of other, classical analytical techniques used to monitor these species in the atmosphere.
Haiyan Li, Thomas Golin Almeida, Yuanyuan Luo, Jian Zhao, Brett B. Palm, Christopher D. Daub, Wei Huang, Claudia Mohr, Jordan E. Krechmer, Theo Kurtén, and Mikael Ehn
Atmos. Meas. Tech., 15, 1811–1827, https://doi.org/10.5194/amt-15-1811-2022, https://doi.org/10.5194/amt-15-1811-2022, 2022
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This work evaluated the potential for PTR-based mass spectrometers to detect ROOR and ROOH peroxides both experimentally and through computations. Laboratory experiments using a Vocus PTR observed only noisy signals of potential dimers during α-pinene ozonolysis and a few small signals of dimeric compounds during cyclohexene ozonolysis. Quantum chemical calculations for model ROOR and ROOH systems showed that most of these peroxides should fragment partially following protonation.
Jean Decker, Éric Fertein, Jonas Bruckhuisen, Nicolas Houzel, Pierre Kulinski, Bo Fang, Weixiong Zhao, Francis Hindle, Guillaume Dhont, Robin Bocquet, Gaël Mouret, Cécile Coeur, and Arnaud Cuisset
Atmos. Meas. Tech., 15, 1201–1215, https://doi.org/10.5194/amt-15-1201-2022, https://doi.org/10.5194/amt-15-1201-2022, 2022
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We present a multiple pass system developed for the CHamber for Atmospheric Reactivity and Metrology of the Environment. This multi-pass cell allows monitoring of atmospheric species at trace levels by high-resolution spectroscopy with long interaction path lengths in the IR and for the first time in the terahertz range. Interesting prospects are highlighted in this frequency domain, such as a high degree of selectivity or the possibility to monitor in real-time atmospheric processes.
Robert F. Berg, Nicola Chiodo, and Eric Georgin
Atmos. Meas. Tech., 15, 819–832, https://doi.org/10.5194/amt-15-819-2022, https://doi.org/10.5194/amt-15-819-2022, 2022
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We made a humidity generator that adds water vapor to a flowing gas. Its range of humidity is useful for calibrating balloon-borne probes to the Earth's stratosphere. The generator’s novel feature is a saturator that comprises 5 m of silicone tubing immersed in water. The length was enough to ensure that the saturator’s output was independent of the dimensions and permeability of the tube. This simple, low-cost design provides an accuracy that is acceptable for many applications.
Guillermo Villena and Jörg Kleffmann
Atmos. Meas. Tech., 15, 627–637, https://doi.org/10.5194/amt-15-627-2022, https://doi.org/10.5194/amt-15-627-2022, 2022
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A continuous source for the generation of pure HONO mixtures was developed and characterized, which is based on the Henry's law solubility of HONO in acidic aqueous solutions. The source shows a fast time response and an excellent long-term stability and can be easily adjusted to HONO mixing ratios in the range 0.05–500 ppb. A general equation based on Henry's law is developed, whereby the HONO concentration of the source can be absolutely calculated with an accuracy of better than 10 %.
Merve Polat, Jesper Baldtzer Liisberg, Morten Krogsbøll, Thomas Blunier, and Matthew S. Johnson
Atmos. Meas. Tech., 14, 8041–8067, https://doi.org/10.5194/amt-14-8041-2021, https://doi.org/10.5194/amt-14-8041-2021, 2021
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We have designed a process for removing methane from a gas stream so that nitrous oxide can be measured without interference. These are both key long-lived greenhouse gases frequently studied in relation to ice cores, plants, water treatment and so on. However, many researchers are not aware of the problem of methane interference, and in addition there have not been good methods available for solving the problem. Here we present and evaluate such a method.
Marcel Snels, Stefania Stefani, Angelo Boccaccini, David Biondi, and Giuseppe Piccioni
Atmos. Meas. Tech., 14, 7187–7197, https://doi.org/10.5194/amt-14-7187-2021, https://doi.org/10.5194/amt-14-7187-2021, 2021
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A novel simulation chamber, PASSxS (Planetary Atmosphere Simulation System for Spectroscopy), has been developed for absorption measurements with a Fourier transform spectrometer (FTS) and possibly a cavity ring-down (CRD) spectrometer, with a sample temperature ranging from 100 K up to 550 K, while the pressure of the gas can be varied up to 60 bar. These temperature and pressure ranges cover a significant part of the planetary atmospheres in the solar system and possibly extrasolar planets.
Lukas Kohl, Markku Koskinen, Tatu Polvinen, Salla Tenhovirta, Kaisa Rissanen, Marjo Patama, Alessandro Zanetti, and Mari Pihlatie
Atmos. Meas. Tech., 14, 4445–4460, https://doi.org/10.5194/amt-14-4445-2021, https://doi.org/10.5194/amt-14-4445-2021, 2021
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We present ShoTGa-FluMS, a measurement system designed for continuous and automated measurements of trace gas and volatile organic compound (VOC) fluxes from plant shoots. ShoTGa-FluMS uses transparent shoot enclosures equipped with cooling elements, automatically replaces fixated CO2, and removes transpired water from the enclosure, thus solving multiple technical problems that have so far prevented automated plant shoot trace gas flux measurements.
Pharahilda M. Steur, Hubertus A. Scheeren, Dave D. Nelson, J. Barry McManus, and Harro A. J. Meijer
Atmos. Meas. Tech., 14, 4279–4304, https://doi.org/10.5194/amt-14-4279-2021, https://doi.org/10.5194/amt-14-4279-2021, 2021
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For understanding the sources and sinks of atmospheric CO2, measurement of stable isotopes has proven to be highly valuable. We present a new method using laser absorption spectroscopy to simultaneously conduct measurements of three CO2 isotopes, directly on dry-air samples. This new method reduces sample preparation time significantly, compared to the conventional method in which measurements are conducted on pure CO2, and avoids measurement biases introduced by CO2 extraction.
Mingyi Wang, Xu-Cheng He, Henning Finkenzeller, Siddharth Iyer, Dexian Chen, Jiali Shen, Mario Simon, Victoria Hofbauer, Jasper Kirkby, Joachim Curtius, Norbert Maier, Theo Kurtén, Douglas R. Worsnop, Markku Kulmala, Matti Rissanen, Rainer Volkamer, Yee Jun Tham, Neil M. Donahue, and Mikko Sipilä
Atmos. Meas. Tech., 14, 4187–4202, https://doi.org/10.5194/amt-14-4187-2021, https://doi.org/10.5194/amt-14-4187-2021, 2021
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Atmospheric iodine species are often short-lived with low abundance and have thus been challenging to measure. We show that the bromide chemical ionization mass spectrometry, compatible with both the atmospheric pressure and reduced pressure interfaces, can simultaneously detect various gas-phase iodine species. Combining calibration experiments and quantum chemical calculations, we quantify detection sensitivities to HOI, HIO3, I2, and H2SO4, giving detection limits down to < 106 molec. cm-3.
Benjamin Birner, William Paplawsky, Jeffrey Severinghaus, and Ralph F. Keeling
Atmos. Meas. Tech., 14, 2515–2527, https://doi.org/10.5194/amt-14-2515-2021, https://doi.org/10.5194/amt-14-2515-2021, 2021
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The atmospheric helium-to-nitrogen ratio is a promising indicator for circulation changes in the upper atmosphere and fossil fuel burning by humans. We present a very precise analysis method to determine changes in the helium-to-nitrogen ratio of air samples. The method relies on stabilizing the gas flow to a mass spectrometer and continuous removal of reactive gases. These advances enable new insights and monitoring possibilities for anthropogenic and natural processes.
Alexander Zaytsev, Martin Breitenlechner, Anna Novelli, Hendrik Fuchs, Daniel A. Knopf, Jesse H. Kroll, and Frank N. Keutsch
Atmos. Meas. Tech., 14, 2501–2513, https://doi.org/10.5194/amt-14-2501-2021, https://doi.org/10.5194/amt-14-2501-2021, 2021
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We have developed an online method for speciated measurements of organic peroxy radicals and stabilized Criegee intermediates using chemical derivatization combined with chemical ionization mass spectrometry. Chemical derivatization prevents secondary radical reactions and eliminates potential interferences. Comparison between our measurements and results from numeric modeling shows that the method can be used for the quantification of a wide range of atmospheric radicals and intermediates.
Einar Karu, Mengze Li, Lisa Ernle, Carl A. M. Brenninkmeijer, Jos Lelieveld, and Jonathan Williams
Atmos. Meas. Tech., 14, 1817–1831, https://doi.org/10.5194/amt-14-1817-2021, https://doi.org/10.5194/amt-14-1817-2021, 2021
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A gas measurement device was developed to measure trace gases (ppt level) in the air based on an atomic emission detector. It combines a cryogenic pre-concentrator (CryoTrap), a gas chromatograph (GC), and a new high-resolution atomic emission detector (AED). The CryoTrap–GC–AED instrumental setup, limits of detection, and elemental performance are presented and discussed. Two measurement case studies are reported: one in a Finnish boreal forest and the other based on an aircraft campaign.
Ikumi Oyabu, Kenji Kawamura, Kyotaro Kitamura, Remi Dallmayr, Akihiro Kitamura, Chikako Sawada, Jeffrey P. Severinghaus, Ross Beaudette, Anaïs Orsi, Satoshi Sugawara, Shigeyuki Ishidoya, Dorthe Dahl-Jensen, Kumiko Goto-Azuma, Shuji Aoki, and Takakiyo Nakazawa
Atmos. Meas. Tech., 13, 6703–6731, https://doi.org/10.5194/amt-13-6703-2020, https://doi.org/10.5194/amt-13-6703-2020, 2020
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Air in polar ice cores provides information on past atmosphere and climate. We present a new method for simultaneously measuring eight gases (CH4, N2O and CO2 concentrations; isotopic ratios of N2 and O2; elemental ratios between N2, O2 and Ar; and total air content) from single ice-core samples with high precision.
Bernhard Bereiter, Béla Tuzson, Philipp Scheidegger, André Kupferschmid, Herbert Looser, Lars Mächler, Daniel Baggenstos, Jochen Schmitt, Hubertus Fischer, and Lukas Emmenegger
Atmos. Meas. Tech., 13, 6391–6406, https://doi.org/10.5194/amt-13-6391-2020, https://doi.org/10.5194/amt-13-6391-2020, 2020
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The record of past greenhouse gas composition from ice cores is crucial for our understanding of global climate change. Deciphering this archive requires highly accurate and spatially resolved analysis of the very small amount of gas that is trapped in the ice. This is achieved with a mid-IR laser absorption spectrometer that provides simultaneous, high-precision measurements of CH4, N2O, CO2, and δ13C(CO2) and which will be coupled to a quantitative sublimation extraction method.
Natalie I. Keehan, Bellamy Brownwood, Andrey Marsavin, Douglas A. Day, and Juliane L. Fry
Atmos. Meas. Tech., 13, 6255–6269, https://doi.org/10.5194/amt-13-6255-2020, https://doi.org/10.5194/amt-13-6255-2020, 2020
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This paper describes a new instrument (a thermal-dissociation–cavity ring-down spectrometer, TD-CRDS) for the measurement of key atmospheric gaseous and particle-phase molecules containing the nitrate functional group. Several operational considerations affecting the measurements are described, as well as several characterization experiments comparing the TD-CRDS measurements to analogous measurements from other instruments. Examples are given using a TD-CRDS for ambient and laboratory studies.
Mohammed S. Alam, Leigh R. Crilley, James D. Lee, Louisa J. Kramer, Christian Pfrang, Mónica Vázquez-Moreno, Milagros Ródenas, Amalia Muñoz, and William J. Bloss
Atmos. Meas. Tech., 13, 5977–5991, https://doi.org/10.5194/amt-13-5977-2020, https://doi.org/10.5194/amt-13-5977-2020, 2020
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We report on the interference arising in measurements of nitrogen oxides (NOx) from the presence of a range of alkenes in sampled air when using the most widespread air quality monitoring technique for chemiluminescence detection. Interferences of up to 11 % are reported, depending upon the alkene present and conditions used. Such interferences may be of substantial importance for the interpretation of ambient NOx data, particularly for high volatile organic compound and low NOx environments.
Daniel Marno, Cheryl Ernest, Korbinian Hens, Umar Javed, Thomas Klimach, Monica Martinez, Markus Rudolf, Jos Lelieveld, and Hartwig Harder
Atmos. Meas. Tech., 13, 2711–2731, https://doi.org/10.5194/amt-13-2711-2020, https://doi.org/10.5194/amt-13-2711-2020, 2020
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In this study, a calibration device for OH and HO2 instruments is characterized at pressures of 275 to 1000 mbar, allowing instrument pressure sensitivity to be quantified to an accuracy of 22 % (1σ). Computational fluid dynamic simulations supporting the understanding of interactions between generated HOx and the instrument inlet led to enhanced determination of factors affecting instrument sensitivity.
Joschka Pfeifer, Mario Simon, Martin Heinritzi, Felix Piel, Lena Weitz, Dongyu Wang, Manuel Granzin, Tatjana Müller, Steffen Bräkling, Jasper Kirkby, Joachim Curtius, and Andreas Kürten
Atmos. Meas. Tech., 13, 2501–2522, https://doi.org/10.5194/amt-13-2501-2020, https://doi.org/10.5194/amt-13-2501-2020, 2020
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Ammonia is an important atmospheric trace gas that affects secondary aerosol formation and, together with sulfuric acid, the formation of new particles. A measurement technique is presented that uses high-resolution mass spectrometry and protonated water clusters for the ultrasensitive detection of ammonia at single-digit parts per trillion by volume levels. The instrument is further capable of measuring amines and a suite of iodine compounds at sub-parts per trillion by volume levels.
Roberto Sommariva, Louisa J. Kramer, Leigh R. Crilley, Mohammed S. Alam, and William J. Bloss
Atmos. Meas. Tech., 13, 1655–1670, https://doi.org/10.5194/amt-13-1655-2020, https://doi.org/10.5194/amt-13-1655-2020, 2020
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Ozone is a key atmospheric pollutant formed through chemical processing of natural and anthropogenic emissions and removed by reaction with organic compounds emitted by plants. We describe a new instrument – the
Total Ozone Reactivity Systemor TORS – that measures the total loss of ozone in the troposphere. The objective of the TORS instrument is to provide an estimate of the organic compounds emitted by plants which are not measured and thus to improve our understanding of the ozone budget.
John W. Birks, Andrew A. Turnipseed, Peter C. Andersen, Craig J. Williford, Stanley Strunk, Brian Carpenter, and Christine A. Ennis
Atmos. Meas. Tech., 13, 1001–1018, https://doi.org/10.5194/amt-13-1001-2020, https://doi.org/10.5194/amt-13-1001-2020, 2020
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We describe a portable calibration source of nitric oxide (NO) based on the photolysis of nitrous oxide. Combining this with a previous photolytic ozone (O3) source yields a calibrator that produces known mixing ratios of NO, O3, and nitrogen dioxide (NO2); NO2 is produced by the reaction of NO with O3. This portable
NO2/NO/O3 calibration source requires no external gas cylinders and can be used as a standard to calibrate O3 and NOx air pollution monitors in the field.
Thomas H. Speak, Mark A. Blitz, Daniel Stone, and Paul W. Seakins
Atmos. Meas. Tech., 13, 839–852, https://doi.org/10.5194/amt-13-839-2020, https://doi.org/10.5194/amt-13-839-2020, 2020
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OH and HO2 radicals are important trace constituents of the atmosphere that are closely coupled via several types of reaction. This paper describes a new laboratory method to simultaneously determine OH kinetics and HO2 yields from chemical processes. The instrument also provides some time resolution on HO2 detection allowing one to separate HO2 produced from the target reaction from HO2 arising from secondary chemistry. Examples of applications are presented.
Ece Satar, Peter Nyfeler, Bernhard Bereiter, Céline Pascale, Bernhard Niederhauser, and Markus Leuenberger
Atmos. Meas. Tech., 13, 101–117, https://doi.org/10.5194/amt-13-101-2020, https://doi.org/10.5194/amt-13-101-2020, 2020
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Good-quality measurements of atmospheric trace gases are only possible with regular calibrations and stable measurements from the standard cylinders. This study investigates instabilities due to surface effects on newly built aluminum and steel cylinders. We present measurements over a set of temperature and pressure ranges for the amount fractions of CO2, CO, CH4 and H2O using a commercial and a novel laser spectroscopic analyzer.
Ece Satar, Peter Nyfeler, Céline Pascale, Bernhard Niederhauser, and Markus Leuenberger
Atmos. Meas. Tech., 13, 119–130, https://doi.org/10.5194/amt-13-119-2020, https://doi.org/10.5194/amt-13-119-2020, 2020
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To ensure the best preparation and measurement conditions for trace gases, usage of coated materials is in demand in gas metrology and atmospheric measurement communities. In this article, the previously introduced aluminum measurement chamber is used to investigate materials such as glass, aluminum, copper, brass, steel and three different commercially available coatings. Our measurements focus on temperature and pressure dependencies for the species CO2, CO, CH4 and H2O using a CRDS analyzer.
Tanja J. Schuck, Ann-Katrin Blank, Elisa Rittmeier, Jonathan Williams, Carl A. M. Brenninkmeijer, Andreas Engel, and Andreas Zahn
Atmos. Meas. Tech., 13, 73–84, https://doi.org/10.5194/amt-13-73-2020, https://doi.org/10.5194/amt-13-73-2020, 2020
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Air sample collection aboard aircraft is a tool to measure atmospheric trace gas mixing ratios at altitude. We present results on the stability of 28 halocarbons during storage of air samples collected in stainless-steel flasks inside an automated air sampling unit which is part of the CARIBIC instrument package. Selected fluorinated compounds grew during the experiments while short-lived compounds were depleted. Individual substances were additionally influenced by high mixing ratios of ozone.
Tesfaye A. Berhanu, John Hoffnagle, Chris Rella, David Kimhak, Peter Nyfeler, and Markus Leuenberger
Atmos. Meas. Tech., 12, 6803–6826, https://doi.org/10.5194/amt-12-6803-2019, https://doi.org/10.5194/amt-12-6803-2019, 2019
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Accurate measurement of variations in atmospheric O2 can provide useful information about atmospheric, biospheric, and oceanic processes, which is a challenge for existing measurement techniques. Here, we introduce a newly built high-precision, stable CRDS analyzer (Picarro G2207) that can measure O2 mixing ratios with a short-term precision of < 1 ppm and only requires calibration every 12 h. Measurements from tower and mountain sites are also presented.
Markus Leiminger, Stefan Feil, Paul Mutschlechner, Arttu Ylisirniö, Daniel Gunsch, Lukas Fischer, Alfons Jordan, Siegfried Schobesberger, Armin Hansel, and Gerhard Steiner
Atmos. Meas. Tech., 12, 5231–5246, https://doi.org/10.5194/amt-12-5231-2019, https://doi.org/10.5194/amt-12-5231-2019, 2019
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We introduce an alternative type of atmospheric pressure interface time-of-flight mass spectrometer (APi-TOF) with the main difference of using hexapole instead of quadrupole ion guides. The transfer of cluster ions through the hexapoles was characterised with focus on transmission efficiency, mass range and fragmentation of cluster ions. At the CERN CLOUD experiment we compared the performance of the ioniAPi-TOF with a standard quadrupole APi-TOF under controlled conditions.
Michal Lacko, Nijing Wang, Kristýna Sovová, Pavel Pásztor, and Patrik Španěl
Atmos. Meas. Tech., 12, 4965–4982, https://doi.org/10.5194/amt-12-4965-2019, https://doi.org/10.5194/amt-12-4965-2019, 2019
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The soft chemical ionization analytical technique of selected ion flow tube mass spectrometry, SIFT-MS, was enhanced by a fast GC pre-separation unit to identify individual isomers. Experiments were carried out with two GC columns, MXT-1 and MXT-Volatiles, using two reagent ions, H3O+ and NO+, on monoterpene samples (an artificial mixture and coniferous needles). Analyses of product ion ratios allowed for quantification of multiple monoterpenes in partially separated chromatograms.
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Short summary
Monitoring ozone layer recovery at a rate of few percent per decade requires dedicated instrumentation and spectroscopic data of the highest quality. Highly accurate absorption cross sections of ozone are rare, especially in the important UV region between 300 and 340 nm. Our measurement provides the first reference point with permil level of accuracy in this range. Interestingly, our value is lower than currently used data. This might resolve an inconsistency between UV and IR measurements.
Monitoring ozone layer recovery at a rate of few percent per decade requires dedicated...
