Articles | Volume 9, issue 8
https://doi.org/10.5194/amt-9-3717-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/amt-9-3717-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
12 Aug 2016
Research article |
| 12 Aug 2016
Development and evaluation of a suite of isotope reference gases for methane in air
Max Planck Institute for Biogeochemistry (MPI-BGC), Jena, Germany
National Institute of Water and Atmospheric Research (NIWA),
Wellington, New Zealand
Nelly A. M. Uitslag
Max Planck Institute for Biogeochemistry (MPI-BGC), Jena, Germany
Centre for Isotope Research (CIO), Energy
and Sustainability Research Institute Groningen (ESRIG),
University of Groningen, Groningen, the Netherlands
Jürgen M. Richter
Max Planck Institute for Biogeochemistry (MPI-BGC), Jena, Germany
Michael Rothe
Max Planck Institute for Biogeochemistry (MPI-BGC), Jena, Germany
Heike Geilmann
Max Planck Institute for Biogeochemistry (MPI-BGC), Jena, Germany
Carina van der Veen
Institute of
Marine and Atmospheric Science in Utrecht (IMAU), Utrecht, the Netherlands
Thomas Röckmann
Institute of
Marine and Atmospheric Science in Utrecht (IMAU), Utrecht, the Netherlands
Thomas Blunier
Centre for Ice and Climate (CIC), Niels Bohr Institute, University
of Copenhagen, Copenhagen, Denmark
Willi A. Brand
Max Planck Institute for Biogeochemistry (MPI-BGC), Jena, Germany
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Roland Vernooij, Ulrike Dusek, Maria Elena Popa, Peng Yao, Anupam Shaikat, Chenxi Qiu, Patrik Winiger, Carina van der Veen, Thomas Callum Eames, Natasha Ribeiro, and Guido R. van der Werf
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Publication in ACP not foreseen
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Using measurements of methane isotopes in ambient air and a 3D atmospheric transport model, in Krakow, Poland, we mainly detected fossil-fuel-related sources, coming from coal mining in Silesia and from the use of natural gas in the city. Emission inventories report large emissions from coal mine activity in Silesia, which is in agreement with our measurements. However, methane sources in the urban area of Krakow related to the use of fossil fuels might be underestimated in the inventories.
Xinyi Lu, Stephen J. Harris, Rebecca E. Fisher, James L. France, Euan G. Nisbet, David Lowry, Thomas Röckmann, Carina van der Veen, Malika Menoud, Stefan Schwietzke, and Bryce F. J. Kelly
Atmos. Chem. Phys., 21, 10527–10555, https://doi.org/10.5194/acp-21-10527-2021, https://doi.org/10.5194/acp-21-10527-2021, 2021
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Many coal seam gas (CSG) facilities in the Surat Basin, Australia, are adjacent to other sources of methane, including agricultural, urban, and natural seeps. This makes it challenging to estimate the amount of methane being emitted into the atmosphere from CSG facilities. This research demonstrates that measurements of the carbon and hydrogen stable isotopic composition of methane can distinguish between and apportion methane emissions from CSG facilities, cattle, and many other sources.
Max Thomas, Johannes C. Laube, Jan Kaiser, Samuel Allin, Patricia Martinerie, Robert Mulvaney, Anna Ridley, Thomas Röckmann, William T. Sturges, and Emmanuel Witrant
Atmos. Chem. Phys., 21, 6857–6873, https://doi.org/10.5194/acp-21-6857-2021, https://doi.org/10.5194/acp-21-6857-2021, 2021
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CFC gases are destroying the Earth's life-protecting ozone layer. We improve understanding of CFC destruction by measuring the isotopic fingerprint of the carbon in the three most abundant CFCs. These are the first such measurements in the main region where CFCs are destroyed – the stratosphere. We reconstruct the atmospheric isotope histories of these CFCs back to the 1950s by measuring air extracted from deep snow and using a model. The model and the measurements are generally consistent.
Michał Gałkowski, Armin Jordan, Michael Rothe, Julia Marshall, Frank-Thomas Koch, Jinxuan Chen, Anna Agusti-Panareda, Andreas Fix, and Christoph Gerbig
Atmos. Meas. Tech., 14, 1525–1544, https://doi.org/10.5194/amt-14-1525-2021, https://doi.org/10.5194/amt-14-1525-2021, 2021
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We present results of atmospheric measurements of greenhouse gases, performed over Europe in 2018 aboard German research aircraft HALO as part of the CoMet 1.0 (Carbon Dioxide and Methane Mission). In our analysis, we describe data quality, discuss observed mixing ratios and show an example of describing a regional methane source using stable isotopic composition based on the collected air samples. We also quantitatively compare our results to selected global atmospheric modelling systems.
Shujiro Komiya, Fumiyoshi Kondo, Heiko Moossen, Thomas Seifert, Uwe Schultz, Heike Geilmann, David Walter, and Jost V. Lavric
Atmos. Meas. Tech., 14, 1439–1455, https://doi.org/10.5194/amt-14-1439-2021, https://doi.org/10.5194/amt-14-1439-2021, 2021
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The Amazon basin influences the atmospheric and hydrological cycles on local to global scales. To better understand how, we plan to perform continuous on-site measurements of the stable isotope composition of atmospheric water vapour. For making accurate on-site observations possible, we have investigated the performance of two commercial analysers and determined the best calibration strategy. Well calibrated, both analysers will allow us to record natural signals in the Amazon rainforest.
Andreas Plach, Bo M. Vinther, Kerim H. Nisancioglu, Sindhu Vudayagiri, and Thomas Blunier
Clim. Past, 17, 317–330, https://doi.org/10.5194/cp-17-317-2021, https://doi.org/10.5194/cp-17-317-2021, 2021
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In light of recent large-scale melting of the Greenland ice sheet
(GrIS), e.g., in the summer of 2012 several days with surface melt
on the entire ice sheet (including elevations above 3000 m), we use
computer simulations to estimate the amount of melt during a
warmer-than-present period of the past. Our simulations show more
extensive melt than today. This is important for the interpretation of
ice cores which are used to reconstruct the evolution of the ice sheet
and the climate.
Hossein Maazallahi, Julianne M. Fernandez, Malika Menoud, Daniel Zavala-Araiza, Zachary D. Weller, Stefan Schwietzke, Joseph C. von Fischer, Hugo Denier van der Gon, and Thomas Röckmann
Atmos. Chem. Phys., 20, 14717–14740, https://doi.org/10.5194/acp-20-14717-2020, https://doi.org/10.5194/acp-20-14717-2020, 2020
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Methane accounts for ∼ 25 % of current climate warming. The current lack of methane measurements is a barrier for tracking major sources, which are key for near-term climate mitigation. We use mobile measurements to identify and quantify methane emission sources in Utrecht (NL) and Hamburg (DE) with a focus on natural gas pipeline leaks. The measurements resulted in fixing the major leaks by the local utility, but coordinated efforts are needed at national levels for further emission reductions.
Joram J. D. Hooghiem, Maria Elena Popa, Thomas Röckmann, Jens-Uwe Grooß, Ines Tritscher, Rolf Müller, Rigel Kivi, and Huilin Chen
Atmos. Chem. Phys., 20, 13985–14003, https://doi.org/10.5194/acp-20-13985-2020, https://doi.org/10.5194/acp-20-13985-2020, 2020
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Wildfires release a large quantity of pollutants that can reach the stratosphere through pyro-convection events. In September 2017, a stratospheric plume was accidentally sampled during balloon soundings in northern Finland. The source of the plume was identified to be wildfire smoke based on in situ measurements of carbon monoxide (CO) and stable isotope analysis of CO. Furthermore, the age of the plume was estimated using backwards transport modelling to be ~24 d, with its origin in Canada.
Alina Fiehn, Julian Kostinek, Maximilian Eckl, Theresa Klausner, Michał Gałkowski, Jinxuan Chen, Christoph Gerbig, Thomas Röckmann, Hossein Maazallahi, Martina Schmidt, Piotr Korbeń, Jarosław Neçki, Pawel Jagoda, Norman Wildmann, Christian Mallaun, Rostyslav Bun, Anna-Leah Nickl, Patrick Jöckel, Andreas Fix, and Anke Roiger
Atmos. Chem. Phys., 20, 12675–12695, https://doi.org/10.5194/acp-20-12675-2020, https://doi.org/10.5194/acp-20-12675-2020, 2020
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A severe reduction of greenhouse gas emissions is necessary to fulfill the Paris Agreement. We use aircraft- and ground-based in situ observations of trace gases and wind speed from two flights over the Upper Silesian Coal Basin, Poland, for independent emission estimation. The derived methane emission estimates are within the range of emission inventories, carbon dioxide estimates are in the lower range and carbon monoxide emission estimates are slightly higher than emission inventory values.
James E. Lee, Edward J. Brook, Nancy A. N. Bertler, Christo Buizert, Troy Baisden, Thomas Blunier, V. Gabriela Ciobanu, Howard Conway, Dorthe Dahl-Jensen, Tyler J. Fudge, Richard Hindmarsh, Elizabeth D. Keller, Frédéric Parrenin, Jeffrey P. Severinghaus, Paul Vallelonga, Edwin D. Waddington, and Mai Winstrup
Clim. Past, 16, 1691–1713, https://doi.org/10.5194/cp-16-1691-2020, https://doi.org/10.5194/cp-16-1691-2020, 2020
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The Roosevelt Island ice core was drilled to investigate climate from the eastern Ross Sea, West Antarctica. We describe the ice age-scale and gas age-scale of the ice core for 0–763 m (83 000 years BP). Old ice near the bottom of the core implies the ice dome existed throughout the last glacial period and that ice streaming was active in the region. Variations in methane, similar to those used as evidence of early human influence on climate, were observed prior to significant human populations.
Jordi Vilà-Guerau de Arellano, Patrizia Ney, Oscar Hartogensis, Hugo de Boer, Kevin van Diepen, Dzhaner Emin, Geiske de Groot, Anne Klosterhalfen, Matthias Langensiepen, Maria Matveeva, Gabriela Miranda-García, Arnold F. Moene, Uwe Rascher, Thomas Röckmann, Getachew Adnew, Nicolas Brüggemann, Youri Rothfuss, and Alexander Graf
Biogeosciences, 17, 4375–4404, https://doi.org/10.5194/bg-17-4375-2020, https://doi.org/10.5194/bg-17-4375-2020, 2020
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The CloudRoots field experiment has obtained an open comprehensive observational data set that includes soil, plant, and atmospheric variables to investigate the interactions between a heterogeneous land surface and its overlying atmospheric boundary layer, including the rapid perturbations of clouds in evapotranspiration. Our findings demonstrate that in order to understand and represent diurnal variability, we need to measure and model processes from the leaf to the landscape scales.
Johannes C. Laube, Emma C. Leedham Elvidge, Karina E. Adcock, Bianca Baier, Carl A. M. Brenninkmeijer, Huilin Chen, Elise S. Droste, Jens-Uwe Grooß, Pauli Heikkinen, Andrew J. Hind, Rigel Kivi, Alexander Lojko, Stephen A. Montzka, David E. Oram, Steve Randall, Thomas Röckmann, William T. Sturges, Colm Sweeney, Max Thomas, Elinor Tuffnell, and Felix Ploeger
Atmos. Chem. Phys., 20, 9771–9782, https://doi.org/10.5194/acp-20-9771-2020, https://doi.org/10.5194/acp-20-9771-2020, 2020
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We demonstrate that AirCore technology, which is based on small low-cost balloons, can provide access to trace gas measurements such as CFCs at ultra-low abundances. This is a new way to quantify ozone-depleting, and related, substances in the stratosphere, which is largely inaccessible to aircraft. We show two potential uses: (a) tracking the stratospheric circulation, which is predicted to change, and (b) assessing three common meteorological reanalyses driving a global stratospheric model.
Anders Svensson, Dorthe Dahl-Jensen, Jørgen Peder Steffensen, Thomas Blunier, Sune O. Rasmussen, Bo M. Vinther, Paul Vallelonga, Emilie Capron, Vasileios Gkinis, Eliza Cook, Helle Astrid Kjær, Raimund Muscheler, Sepp Kipfstuhl, Frank Wilhelms, Thomas F. Stocker, Hubertus Fischer, Florian Adolphi, Tobias Erhardt, Michael Sigl, Amaelle Landais, Frédéric Parrenin, Christo Buizert, Joseph R. McConnell, Mirko Severi, Robert Mulvaney, and Matthias Bigler
Clim. Past, 16, 1565–1580, https://doi.org/10.5194/cp-16-1565-2020, https://doi.org/10.5194/cp-16-1565-2020, 2020
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We identify signatures of large bipolar volcanic eruptions in Greenland and Antarctic ice cores during the last glacial period, which allows for a precise temporal alignment of the ice cores. Thereby the exact timing of unexplained, abrupt climatic changes occurring during the last glacial period can be determined in a global context. The study thus provides a step towards a full understanding of elements of the climate system that may also play an important role in the future.
Getachew Agmuas Adnew, Thijs L. Pons, Gerbrand Koren, Wouter Peters, and Thomas Röckmann
Biogeosciences, 17, 3903–3922, https://doi.org/10.5194/bg-17-3903-2020, https://doi.org/10.5194/bg-17-3903-2020, 2020
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We measured the effect of photosynthesis, the largest flux in the carbon cycle, on the triple oxygen isotope composition of atmospheric CO2 at the leaf level during gas exchange using three plant species. The main factors that limit the impact of land vegetation on the triple oxygen isotope composition of atmospheric CO2 are identified, characterized and discussed. The effect of photosynthesis on the isotopic composition of CO2 is commonly quantified as discrimination (ΔA).
Stephen J. Harris, Jesper Liisberg, Longlong Xia, Jing Wei, Kerstin Zeyer, Longfei Yu, Matti Barthel, Benjamin Wolf, Bryce F. J. Kelly, Dioni I. Cendón, Thomas Blunier, Johan Six, and Joachim Mohn
Atmos. Meas. Tech., 13, 2797–2831, https://doi.org/10.5194/amt-13-2797-2020, https://doi.org/10.5194/amt-13-2797-2020, 2020
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The latest commercial laser spectrometers have the potential to revolutionize N2O isotope analysis. However, to do so, they must be able to produce trustworthy data. Here, we test the performance of widely used laser spectrometers for ambient air applications and identify instrument-specific dependencies on gas matrix and trace gas concentrations. We then provide a calibration workflow to facilitate the operation of these instruments in order to generate reproducible and accurate data.
Jia Chen, Florian Dietrich, Hossein Maazallahi, Andreas Forstmaier, Dominik Winkler, Magdalena E. G. Hofmann, Hugo Denier van der Gon, and Thomas Röckmann
Atmos. Chem. Phys., 20, 3683–3696, https://doi.org/10.5194/acp-20-3683-2020, https://doi.org/10.5194/acp-20-3683-2020, 2020
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We demonstrate for the first time that large festivals can be significant methane sources, though they are not included in emission inventories. We combined in situ measurements with a Gaussian plume model to determine the Oktoberfest emissions and show that they are not due solely to human biogenic emissions, but are instead primarily fossil fuel related. Our study provides the foundation to develop reduction policies for such events and new pathways to mitigate fossil fuel methane emissions.
Stefan Lossow, Charlotta Högberg, Farahnaz Khosrawi, Gabriele P. Stiller, Ralf Bauer, Kaley A. Walker, Sylvia Kellmann, Andrea Linden, Michael Kiefer, Norbert Glatthor, Thomas von Clarmann, Donal P. Murtagh, Jörg Steinwagner, Thomas Röckmann, and Roland Eichinger
Atmos. Meas. Tech., 13, 287–308, https://doi.org/10.5194/amt-13-287-2020, https://doi.org/10.5194/amt-13-287-2020, 2020
Marco de Bruine, Maarten Krol, Jordi Vilà-Guerau de Arellano, and Thomas Röckmann
Geosci. Model Dev., 12, 5177–5196, https://doi.org/10.5194/gmd-12-5177-2019, https://doi.org/10.5194/gmd-12-5177-2019, 2019
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An aerosol scheme with multiple aerosol species is introduced in the Dutch Atmospheric Large-Eddy Simulation model (DALES) and focused to simulate the feedback of aerosol–cloud interaction (ACI) on the aerosol population. Cloud aerosol processing is found to be sensitive to the numerical method, while removal by precipitation is more stable. How ACI increases or decreases the mean aerosol size depends on the balance between the evaporation of clouds/rain and ultimate removal by precipitation.
Mai Winstrup, Paul Vallelonga, Helle A. Kjær, Tyler J. Fudge, James E. Lee, Marie H. Riis, Ross Edwards, Nancy A. N. Bertler, Thomas Blunier, Ed J. Brook, Christo Buizert, Gabriela Ciobanu, Howard Conway, Dorthe Dahl-Jensen, Aja Ellis, B. Daniel Emanuelsson, Richard C. A. Hindmarsh, Elizabeth D. Keller, Andrei V. Kurbatov, Paul A. Mayewski, Peter D. Neff, Rebecca L. Pyne, Marius F. Simonsen, Anders Svensson, Andrea Tuohy, Edwin D. Waddington, and Sarah Wheatley
Clim. Past, 15, 751–779, https://doi.org/10.5194/cp-15-751-2019, https://doi.org/10.5194/cp-15-751-2019, 2019
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We present a 2700-year timescale and snow accumulation history for an ice core from Roosevelt Island, Ross Ice Shelf, Antarctica. We observe a long-term slightly decreasing trend in accumulation during most of the period but a rapid decline since the mid-1960s. The latter is linked to a recent strengthening of the Amundsen Sea Low and the expansion of regional sea ice. The year 1965 CE may thus mark the onset of significant increases in sea-ice extent in the eastern Ross Sea.
Iris N. Dekker, Sander Houweling, Sudhanshu Pandey, Maarten Krol, Thomas Röckmann, Tobias Borsdorff, Jochen Landgraf, and Ilse Aben
Atmos. Chem. Phys., 19, 3433–3445, https://doi.org/10.5194/acp-19-3433-2019, https://doi.org/10.5194/acp-19-3433-2019, 2019
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During November 2017, very high pollution levels were measured in the northern part of India. In this study, satellite (TROPOMI) data and model (WRF) data on carbon monoxide (CO) are studied to investigate the main sources of the CO pollution over the Indo-Gangetic Plain. We found that residential and commercial combustion was a much more important source of CO than the post-monsoon crop burning during this period. Meteorology was found important in the accumulation and ventilation of CO.
Dušan Materić, Elke Ludewig, Kangming Xu, Thomas Röckmann, and Rupert Holzinger
The Cryosphere, 13, 297–307, https://doi.org/10.5194/tc-13-297-2019, https://doi.org/10.5194/tc-13-297-2019, 2019
Jonas Beck, Michael Bock, Jochen Schmitt, Barbara Seth, Thomas Blunier, and Hubertus Fischer
Biogeosciences, 15, 7155–7175, https://doi.org/10.5194/bg-15-7155-2018, https://doi.org/10.5194/bg-15-7155-2018, 2018
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Ice core concentration and stable isotope measurements of atmospheric CH4 give valuable insights into the CH4 cycle of the past. New carbon and hydrogen stable isotope CH4 data measured on ice from both Greenland and Antarctica over the Holocene allow us to draw conclusions on the methane emission processes. In particular, our results cast doubt on a hypothesis proposing early human land use to be responsible for the atmospheric methane concentration increase in the second half of the Holocene.
Marco de Bruine, Maarten Krol, Twan van Noije, Philippe Le Sager, and Thomas Röckmann
Geosci. Model Dev., 11, 1443–1465, https://doi.org/10.5194/gmd-11-1443-2018, https://doi.org/10.5194/gmd-11-1443-2018, 2018
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Precipitation evaporation (PE) and subsequent aerosol resuspension (AR) are currently ignored or implemented only crudely in GCMs. This research introduces PE to Earth system model EC-Earth and explores ways to treat AR and the impact on global aerosol burden. Simple 1:1 scaling of AR with PE leads to an increase (+8 to 15.9 %). Taking into account raindrop size distribution and/or accounting for in-rain aerosol processing decreases aerosol burden -1.5 to 6.2 % and -10 to -11 %, respectively.
Karina E. Adcock, Claire E. Reeves, Lauren J. Gooch, Emma C. Leedham Elvidge, Matthew J. Ashfold, Carl A. M. Brenninkmeijer, Charles Chou, Paul J. Fraser, Ray L. Langenfelds, Norfazrin Mohd Hanif, Simon O'Doherty, David E. Oram, Chang-Feng Ou-Yang, Siew Moi Phang, Azizan Abu Samah, Thomas Röckmann, William T. Sturges, and Johannes C. Laube
Atmos. Chem. Phys., 18, 4737–4751, https://doi.org/10.5194/acp-18-4737-2018, https://doi.org/10.5194/acp-18-4737-2018, 2018
Emma C. Leedham Elvidge, Harald Bönisch, Carl A. M. Brenninkmeijer, Andreas Engel, Paul J. Fraser, Eileen Gallacher, Ray Langenfelds, Jens Mühle, David E. Oram, Eric A. Ray, Anna R. Ridley, Thomas Röckmann, William T. Sturges, Ray F. Weiss, and Johannes C. Laube
Atmos. Chem. Phys., 18, 3369–3385, https://doi.org/10.5194/acp-18-3369-2018, https://doi.org/10.5194/acp-18-3369-2018, 2018
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Chemical species measured in stratospheric air can be used as proxies for stratospheric circulation changes which cannot be measured directly. A range of tracers is important to understand changing stratospheric dynamics. We demonstrate the suitability of PFCs and HFCs as tracers and support recent work that reduces the current stratospheric lifetime of SF6. Updates to policy-relevant parameters (e.g. stratospheric lifetime) linked to this change are provided for O3-depleting substances.
Taku Umezawa, Carl A. M. Brenninkmeijer, Thomas Röckmann, Carina van der Veen, Stanley C. Tyler, Ryo Fujita, Shinji Morimoto, Shuji Aoki, Todd Sowers, Jochen Schmitt, Michael Bock, Jonas Beck, Hubertus Fischer, Sylvia E. Michel, Bruce H. Vaughn, John B. Miller, James W. C. White, Gordon Brailsford, Hinrich Schaefer, Peter Sperlich, Willi A. Brand, Michael Rothe, Thomas Blunier, David Lowry, Rebecca E. Fisher, Euan G. Nisbet, Andrew L. Rice, Peter Bergamaschi, Cordelia Veidt, and Ingeborg Levin
Atmos. Meas. Tech., 11, 1207–1231, https://doi.org/10.5194/amt-11-1207-2018, https://doi.org/10.5194/amt-11-1207-2018, 2018
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Isotope measurements are useful for separating different methane sources. However, the lack of widely accepted standards and calibration methods for stable carbon and hydrogen isotopic ratios of methane in air has caused significant measurement offsets among laboratories. We conducted worldwide interlaboratory comparisons, surveyed the literature and assessed them systematically. This study may be of help in future attempts to harmonize data sets of isotopic composition of atmospheric methane.
Nancy A. N. Bertler, Howard Conway, Dorthe Dahl-Jensen, Daniel B. Emanuelsson, Mai Winstrup, Paul T. Vallelonga, James E. Lee, Ed J. Brook, Jeffrey P. Severinghaus, Taylor J. Fudge, Elizabeth D. Keller, W. Troy Baisden, Richard C. A. Hindmarsh, Peter D. Neff, Thomas Blunier, Ross Edwards, Paul A. Mayewski, Sepp Kipfstuhl, Christo Buizert, Silvia Canessa, Ruzica Dadic, Helle A. Kjær, Andrei Kurbatov, Dongqi Zhang, Edwin D. Waddington, Giovanni Baccolo, Thomas Beers, Hannah J. Brightley, Lionel Carter, David Clemens-Sewall, Viorela G. Ciobanu, Barbara Delmonte, Lukas Eling, Aja Ellis, Shruthi Ganesh, Nicholas R. Golledge, Skylar Haines, Michael Handley, Robert L. Hawley, Chad M. Hogan, Katelyn M. Johnson, Elena Korotkikh, Daniel P. Lowry, Darcy Mandeno, Robert M. McKay, James A. Menking, Timothy R. Naish, Caroline Noerling, Agathe Ollive, Anaïs Orsi, Bernadette C. Proemse, Alexander R. Pyne, Rebecca L. Pyne, James Renwick, Reed P. Scherer, Stefanie Semper, Marius Simonsen, Sharon B. Sneed, Eric J. Steig, Andrea Tuohy, Abhijith Ulayottil Venugopal, Fernando Valero-Delgado, Janani Venkatesh, Feitang Wang, Shimeng Wang, Dominic A. Winski, V. Holly L. Winton, Arran Whiteford, Cunde Xiao, Jiao Yang, and Xin Zhang
Clim. Past, 14, 193–214, https://doi.org/10.5194/cp-14-193-2018, https://doi.org/10.5194/cp-14-193-2018, 2018
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Temperature and snow accumulation records from the annually dated Roosevelt Island Climate Evolution (RICE) ice core show that for the past 2 700 years, the eastern Ross Sea warmed, while the western Ross Sea showed no trend and West Antarctica cooled. From the 17th century onwards, this dipole relationship changed. Now all three regions show concurrent warming, with snow accumulation declining in West Antarctica and the eastern Ross Sea.
Malte Winther, David Balslev-Harder, Søren Christensen, Anders Priemé, Bo Elberling, Eric Crosson, and Thomas Blunier
Biogeosciences, 15, 767–780, https://doi.org/10.5194/bg-15-767-2018, https://doi.org/10.5194/bg-15-767-2018, 2018
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Nitrous oxide (N2O) is an important and strong greenhouse gas in the atmosphere and part of climate. N2O is produced by microbes in terrestrial and aquatic ecosystems. The properties of each specific molecule can be used to determine the source. We implemented continuous measurements of N2O during incubation of denitrifying bacteria and believe that similar experiments will lead to a better understanding of N2O turnover and on the biotic mechanisms behind greenhouse gas exchange of the globe.
Iris N. Dekker, Sander Houweling, Ilse Aben, Thomas Röckmann, Maarten Krol, Sara Martínez-Alonso, Merritt N. Deeter, and Helen M. Worden
Atmos. Chem. Phys., 17, 14675–14694, https://doi.org/10.5194/acp-17-14675-2017, https://doi.org/10.5194/acp-17-14675-2017, 2017
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This study estimates carbon monoxide emissions from the city of Madrid using MOPITT satellite data. There are two methods used and reviewed in this paper: a method that can only estimate a trend in the emission and a newly developed method that also includes model data from WRF to quantify the emissions. We find Madrid CO emissions to be lower by 48 % for 2002 and by 17 % for 2006 compared with the EdgarV4.2 emission inventory, but uncertainty (20 to 50 %) remains.
Carl Meusinger, Ulrike Dusek, Stephanie M. King, Rupert Holzinger, Thomas Rosenørn, Peter Sperlich, Maxime Julien, Gerald S. Remaud, Merete Bilde, Thomas Röckmann, and Matthew S. Johnson
Atmos. Chem. Phys., 17, 6373–6391, https://doi.org/10.5194/acp-17-6373-2017, https://doi.org/10.5194/acp-17-6373-2017, 2017
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Isotope studies can constrain budgets of secondary organic aerosol (SOA) that is pivotal to air pollution and climate. SOA from α-pinene ozonolysis was found to be enriched in 13C relative to the precursor. The observed difference in 13C between the gas and particle phases may arise from isotope-dependent changes in branching ratios. Alternatively, some gas-phase products involve carbon atoms from highly enriched and depleted sites, giving a non-kinetic origin to the observed fractionations.
Célia J. Sapart, Natalia Shakhova, Igor Semiletov, Joachim Jansen, Sönke Szidat, Denis Kosmach, Oleg Dudarev, Carina van der Veen, Matthias Egger, Valentine Sergienko, Anatoly Salyuk, Vladimir Tumskoy, Jean-Louis Tison, and Thomas Röckmann
Biogeosciences, 14, 2283–2292, https://doi.org/10.5194/bg-14-2283-2017, https://doi.org/10.5194/bg-14-2283-2017, 2017
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The Arctic Ocean, especially the Siberian shelves, overlays large areas of subsea permafrost that is degrading. We show that methane with a biogenic origin is emitted from this permafrost. At locations where bubble plumes have been observed, methane can escape oxidation in the surface sediment and rapidly migrate through the very shallow water column of this region to escape to the atmosphere, generating a positive radiative feedback.
Markella Prokopiou, Patricia Martinerie, Célia J. Sapart, Emmanuel Witrant, Guillaume Monteil, Kentaro Ishijima, Sophie Bernard, Jan Kaiser, Ingeborg Levin, Thomas Blunier, David Etheridge, Ed Dlugokencky, Roderik S. W. van de Wal, and Thomas Röckmann
Atmos. Chem. Phys., 17, 4539–4564, https://doi.org/10.5194/acp-17-4539-2017, https://doi.org/10.5194/acp-17-4539-2017, 2017
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Nitrous oxide is the third most important anthropogenic greenhouse gas with an increasing mole fraction. To understand its natural and anthropogenic sources
we employ isotope measurements. Results show that while the N2O mole fraction increases, its heavy isotope content decreases. The isotopic changes observed underline the dominance of agricultural emissions especially at the early part of the record, whereas in the later decades the contribution from other anthropogenic sources increases.
Ulrike Dusek, Regina Hitzenberger, Anne Kasper-Giebl, Magdalena Kistler, Harro A. J. Meijer, Sönke Szidat, Lukas Wacker, Rupert Holzinger, and Thomas Röckmann
Atmos. Chem. Phys., 17, 3233–3251, https://doi.org/10.5194/acp-17-3233-2017, https://doi.org/10.5194/acp-17-3233-2017, 2017
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Measurements of the radioactive carbon isotope 14C allow to identify the sources of aerosol carbon. We report an extensive 14C source apportionment record in the Netherlands with samples covering a whole year. We discovered that long-range transport has a large influence on aerosol carbon levels. Fossil fuel carbon is least influenced by long-range transport and more regional in origin. Biomass burning seems to be a minor source of aerosol carbon in the Netherlands.
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
Dorota Janina Mrozek, Carina van der Veen, Magdalena E. G. Hofmann, Huilin Chen, Rigel Kivi, Pauli Heikkinen, and Thomas Röckmann
Atmos. Meas. Tech., 9, 5607–5620, https://doi.org/10.5194/amt-9-5607-2016, https://doi.org/10.5194/amt-9-5607-2016, 2016
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Stratospheric Air Sub-sampler (SAS) is a device to collect and to store the stratospheric profile of air collected with an AirCore (Karion et al., 2010) in numerous sub-samples. The sub-samples (each of 25 mL at ambient temperature and pressure) can be later introduced to the continuous flow systems to measure for example the isotopic composition of CO2. The performance of the coupled system is demonstrated for a set of air samples from an AirCore flight in November 2014 near Sodankylä, Finland.
Beatriz Sayuri Oyama, Maria de Fátima Andrade, Pierre Herckes, Ulrike Dusek, Thomas Röckmann, and Rupert Holzinger
Atmos. Chem. Phys., 16, 14397–14408, https://doi.org/10.5194/acp-16-14397-2016, https://doi.org/10.5194/acp-16-14397-2016, 2016
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Vehicular emissions have a strong impact on air pollution in big cities; hence, the study was performed in São Paulo city, where light- (LDVs) and heavy-duty vehicles (HDVs) run on different fuels. We find that organic aerosol emission from LDVs and HDVs is a complex process involving oxidation of fuel constituents, NOx chemistry, and condensation of unburned fuel hydrocarbons on new or existing particles. The obtained emission patterns can be used to study processing of young aerosol in Brazil.
Linda M. J. Kooijmans, Nelly A. M. Uitslag, Mark S. Zahniser, David D. Nelson, Stephen A. Montzka, and Huilin Chen
Atmos. Meas. Tech., 9, 5293–5314, https://doi.org/10.5194/amt-9-5293-2016, https://doi.org/10.5194/amt-9-5293-2016, 2016
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The accuracy of carbon models, used for the prediction of global climate change, is limited by the knowledge of the uptake of carbon by plants through photosynthesis. Carbonyl sulfide (COS) has been suggested as a tracer for this process. To be able to further explore and verify the application of this novel tracer we have tested a laser spectrometer for its suitability to obtain accurate and high precision measurements of COS and CO2 with both laboratory experiments and field measurements.
Matthias Egger, Peter Kraal, Tom Jilbert, Fatimah Sulu-Gambari, Célia J. Sapart, Thomas Röckmann, and Caroline P. Slomp
Biogeosciences, 13, 5333–5355, https://doi.org/10.5194/bg-13-5333-2016, https://doi.org/10.5194/bg-13-5333-2016, 2016
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By combining detailed geochemical analyses with diagenetic modeling, we provide new insights into how methane dynamics may strongly overprint burial records of iron, sulfur and phosphorus in marine systems subject to changes in organic matter loading or water column salinity. A better understanding of these processes will improve our ability to read ancient sediment records and thus to predict the potential consequences of global warming and human-enhanced inputs of nutrients to the ocean.
Cathy M. Trudinger, Paul J. Fraser, David M. Etheridge, William T. Sturges, Martin K. Vollmer, Matt Rigby, Patricia Martinerie, Jens Mühle, David R. Worton, Paul B. Krummel, L. Paul Steele, Benjamin R. Miller, Johannes Laube, Francis S. Mani, Peter J. Rayner, Christina M. Harth, Emmanuel Witrant, Thomas Blunier, Jakob Schwander, Simon O'Doherty, and Mark Battle
Atmos. Chem. Phys., 16, 11733–11754, https://doi.org/10.5194/acp-16-11733-2016, https://doi.org/10.5194/acp-16-11733-2016, 2016
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Perfluorocarbons (PFCs) are potent, long-lived and mostly man-made greenhouse gases released to the atmosphere mainly during aluminium production and semiconductor manufacture. Here we present the first continuous histories of three PFCs from 1800 to 2014, derived from measurements of these PFCs in the atmosphere and in air bubbles in polar ice. The records show how human actions have affected these important greenhouse gases over the past century.
Thomas Röckmann, Simon Eyer, Carina van der Veen, Maria E. Popa, Béla Tuzson, Guillaume Monteil, Sander Houweling, Eliza Harris, Dominik Brunner, Hubertus Fischer, Giulia Zazzeri, David Lowry, Euan G. Nisbet, Willi A. Brand, Jaroslav M. Necki, Lukas Emmenegger, and Joachim Mohn
Atmos. Chem. Phys., 16, 10469–10487, https://doi.org/10.5194/acp-16-10469-2016, https://doi.org/10.5194/acp-16-10469-2016, 2016
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A dual isotope ratio mass spectrometric system (IRMS) and a quantum cascade laser absorption spectroscopy (QCLAS)-based technique were deployed at the Cabauw experimental site for atmospheric research (CESAR) in the Netherlands and performed in situ, high-frequency (approx. hourly) measurements for a period of more than 5 months, yielding a combined dataset with more than 2500 measurements of both δ13C and δD.
Theo Manuel Jenk, Mauro Rubino, David Etheridge, Viorela Gabriela Ciobanu, and Thomas Blunier
Atmos. Meas. Tech., 9, 3687–3706, https://doi.org/10.5194/amt-9-3687-2016, https://doi.org/10.5194/amt-9-3687-2016, 2016
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Atmospheric CO2 and δ13C-CO2 records from polar ice cores provide important constraints on the natural carbon cycle variability. Still, data exist only from a limited number of sampling sites and time periods due to demanding analytical challenges. Additional analytical state-of-the-art resources are desirable. This study describes such a new facility. Its analytical performance and new approaches for dealing with procedural blank contribution and analytical outliers are discussed in detail.
Malte Winther, David Balslev-Harder, Søren Christensen, Anders Priemé, Bo Elberling, Eric Crosson, and Thomas Blunier
Biogeosciences Discuss., https://doi.org/10.5194/bg-2016-258, https://doi.org/10.5194/bg-2016-258, 2016
Revised manuscript not accepted
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Nitrous oxide (N2O) is an important and strong greenhouse gas in the atmosphere and part of climate. N2O is produced by microbes in terrestrial and aquatic ecosystems. The properties of each specific molecule can be used to determine the source. We implemented continuous measurements of N2O during incubation of denitrifying bacteria and believe that similar experiments will lead to a better understanding of N2O turnover and on the biotic mechanisms behind greenhouse gas exchange of the Globe.
Rachael H. Rhodes, Xavier Faïn, Edward J. Brook, Joseph R. McConnell, Olivia J. Maselli, Michael Sigl, Jon Edwards, Christo Buizert, Thomas Blunier, Jérôme Chappellaz, and Johannes Freitag
Clim. Past, 12, 1061–1077, https://doi.org/10.5194/cp-12-1061-2016, https://doi.org/10.5194/cp-12-1061-2016, 2016
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Local artifacts in ice core methane data are superimposed on consistent records of past atmospheric variability. These artifacts are not related to past atmospheric history and care should be taken to avoid interpreting them as such. By investigating five polar ice cores from sites with different conditions, we relate isolated methane spikes to melt layers and decimetre-scale variations as "trapping signal" associated with a difference in timing of air bubble closure in adjacent firn layers.
Sudhanshu Pandey, Sander Houweling, Maarten Krol, Ilse Aben, Frédéric Chevallier, Edward J. Dlugokencky, Luciana V. Gatti, Emanuel Gloor, John B. Miller, Rob Detmers, Toshinobu Machida, and Thomas Röckmann
Atmos. Chem. Phys., 16, 5043–5062, https://doi.org/10.5194/acp-16-5043-2016, https://doi.org/10.5194/acp-16-5043-2016, 2016
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This study investigates the constraint provided by measurements of Xratio (XCH4/XCO2) from space on surface fluxes of CH4 and CO2. We apply the ratio inversion method described in Pandey et al. (2015) to Xratio retrievals from the GOSAT with the TM5-4DVAR inverse modeling system, to constrain the surface fluxes of CH4 and CO2 for 2009 and 2010. The results are compared to proxy CH4 inversions using model-derived-XCO2 mixing ratios from CarbonTracker and MACC.
L. M. T. Joelsson, J. A. Schmidt, E. J. K. Nilsson, T. Blunier, D. W. T. Griffith, S. Ono, and M. S. Johnson
Atmos. Chem. Phys., 16, 4439–4449, https://doi.org/10.5194/acp-16-4439-2016, https://doi.org/10.5194/acp-16-4439-2016, 2016
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We present experimental kinetic isotope effects (KIE) for the OH oxidation of CH3D and 13CH3D and their temperature dependence. Our determination of the 13CH3D + OH KIE is novel and we find no "clumped" isotope effect within the experimental uncertainty.
S. Eyer, B. Tuzson, M. E. Popa, C. van der Veen, T. Röckmann, M. Rothe, W. A. Brand, R. Fisher, D. Lowry, E. G. Nisbet, M. S. Brennwald, E. Harris, C. Zellweger, L. Emmenegger, H. Fischer, and J. Mohn
Atmos. Meas. Tech., 9, 263–280, https://doi.org/10.5194/amt-9-263-2016, https://doi.org/10.5194/amt-9-263-2016, 2016
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We present a newly developed field-deployable, autonomous platform simultaneously measuring the three most abundant isotopologues of methane using mid-infrared laser absorption spectroscopy.
The instrument consists of a compact quantum cascade laser absorption spectrometer (QCLAS) coupled to a preconcentration unit, called TRace gas EXtractor (TREX).
The performance of this new in situ technique was investigated during a 2-week measurement campaign and compared to other techniques.
N. Bândă, M. Krol, M. van Weele, T. van Noije, P. Le Sager, and T. Röckmann
Atmos. Chem. Phys., 16, 195–214, https://doi.org/10.5194/acp-16-195-2016, https://doi.org/10.5194/acp-16-195-2016, 2016
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We quantify the processes responsible for methane growth rate variability in the period 1990 to 1995, a period with variations in climate and radiation due to the Pinatubo eruption. We find significant contributions from changes in the methane emission from wetlands, and in the methane removal by OH caused by stratospheric aerosols, by the decrease in temperature and water vapour, by stratospheric ozone depletion and by changes in emissions of CO and NMVOC.
S. Walter, A. Kock, T. Steinhoff, B. Fiedler, P. Fietzek, J. Kaiser, M. Krol, M. E. Popa, Q. Chen, T. Tanhua, and T. Röckmann
Biogeosciences, 13, 323–340, https://doi.org/10.5194/bg-13-323-2016, https://doi.org/10.5194/bg-13-323-2016, 2016
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Oceans are a source of H2, an indirect greenhouse gas. Measurements constraining the temporal and spatial patterns of oceanic H2 emissions are sparse and although H2 is assumed to be produced mainly biologically, direct evidence for biogenic marine production was lacking. By analyzing the H2 isotopic composition (δD) we were able to constrain the global H2 budget in more detail, verify biogenic production and point to additional sources. We also showed that current models are reasonably working.
S. L. Pathirana, C. van der Veen, M. E. Popa, and T. Röckmann
Atmos. Meas. Tech., 8, 5315–5324, https://doi.org/10.5194/amt-8-5315-2015, https://doi.org/10.5194/amt-8-5315-2015, 2015
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CO is established as an important indirect greenhouse gas, as it is the major sink for the OH∙. We have developed a fully automated system for the determination of δ13C and δ18O in atmospheric CO. The blank signal of the Schütze reagent is 1-3 % of the typical sample size. The repeatability is 0.1 ‰ for δ13C and 0.2 ‰ for δ18O. The analytical repeatability for the mole fraction is ~0.7 nmol mol-1 for 100 mL of ambient air (185.4 nmol mol-1 of CO). A single measurement is performed in 18 min.
Q. Chen, M. E. Popa, A. M. Batenburg, and T. Röckmann
Atmos. Chem. Phys., 15, 13003–13021, https://doi.org/10.5194/acp-15-13003-2015, https://doi.org/10.5194/acp-15-13003-2015, 2015
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We investigated soil production and uptake of H2 and associated isotope effects. Uptake and emission of H2 occurred simultaneously at all sampling sites, with strongest emission where N2 fixing legume was present. The fractionation constant during soil uptake was about 0.945 and it did not show positive correlation with deposition velocity. The isotopic composition of H2 emitted from soil with legume was about -530‰, which is less deuterium-depleted than isotope equilibrium between H2O and H2.
C. Reutenauer, A. Landais, T. Blunier, C. Bréant, M. Kageyama, M.-N. Woillez, C. Risi, V. Mariotti, and P. Braconnot
Clim. Past, 11, 1527–1551, https://doi.org/10.5194/cp-11-1527-2015, https://doi.org/10.5194/cp-11-1527-2015, 2015
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Isotopes of atmospheric O2 undergo millennial-scale variations during the last glacial period, and systematically increase during Heinrich stadials.
Such variations are mostly due to vegetation and water cycle processes.
Our modeling approach reproduces the main observed features of Heinrich stadials in terms of climate, vegetation and rainfall.
It highlights the strong role of hydrology on O2 isotopes, which can be seen as a global integrator of precipitation changes over vegetated areas.
S. Pandey, S. Houweling, M. Krol, I. Aben, and T. Röckmann
Atmos. Chem. Phys., 15, 8615–8629, https://doi.org/10.5194/acp-15-8615-2015, https://doi.org/10.5194/acp-15-8615-2015, 2015
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This study attempts to determine the feasibility of a new assimilation method of satellite measurements of CH4 and CO2 for optimization of their surface fluxes in a synthetic environment. Instead of their absolute concentrations, we assimilate the ratios of their concentrations (CH4/CO2) in our inversion. Doing so helps us to reduce the effect of atmospheric scattering on the measurements in our system. However, assimilation of the ratios makes the inversion non-linear.
K. Ishijima, M. Takigawa, K. Sudo, S. Toyoda, N. Yoshida, T. Röckmann, J. Kaiser, S. Aoki, S. Morimoto, S. Sugawara, and T. Nakazawa
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-15-19947-2015, https://doi.org/10.5194/acpd-15-19947-2015, 2015
Revised manuscript not accepted
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We developed an atmospheric N2O isotopocule model based on a chemistry-coupled atmospheric general circulation model and a simple method to optimize the model, and estimated the isotopic signatures of surface sources at the hemispheric scale. Data obtained from ground-based observations, measurements of firn air, and balloon and aircraft flights were used to optimize the long-term trends, interhemispheric gradients, and photolytic fractionation, respectively, in the model.
S. J. Allin, J. C. Laube, E. Witrant, J. Kaiser, E. McKenna, P. Dennis, R. Mulvaney, E. Capron, P. Martinerie, T. Röckmann, T. Blunier, J. Schwander, P. J. Fraser, R. L. Langenfelds, and W. T. Sturges
Atmos. Chem. Phys., 15, 6867–6877, https://doi.org/10.5194/acp-15-6867-2015, https://doi.org/10.5194/acp-15-6867-2015, 2015
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Stratospheric ozone protects life on Earth from harmful UV-B radiation. Chlorofluorocarbons (CFCs) are man-made compounds which act to destroy this barrier.
This paper presents (1) the first measurements of the stratospheric δ(37Cl) of CFCs -11 and -113; (2) the first quantification of long-term trends in the tropospheric δ(37Cl) of CFCs -11, -12 and -113.
This study provides a better understanding of source and sink processes associated with these destructive compounds.
F. A. Stap, O. P. Hasekamp, and T. Röckmann
Atmos. Meas. Tech., 8, 1287–1301, https://doi.org/10.5194/amt-8-1287-2015, https://doi.org/10.5194/amt-8-1287-2015, 2015
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We present the capability of an aerosol retrieval algorithm, intended for multi-angle, multi-wavelength photopolarimetric measurements, to intrinsically screen for sub-pixel liquid water cloud contamination.
The screening is based on goodness-of-fit criteria. The algorithm has been applied to a synthetic data set of partially clouded scenes and (non-cloud-screened) POLDER3/PARASOL observations.
S. J. Sutanto, G. Hoffmann, R. A. Scheepmaker, J. Worden, S. Houweling, K. Yoshimura, I. Aben, and T. Röckmann
Atmos. Meas. Tech., 8, 999–1019, https://doi.org/10.5194/amt-8-999-2015, https://doi.org/10.5194/amt-8-999-2015, 2015
D. J. Mrozek, C. van der Veen, M. Kliphuis, J. Kaiser, A. A. Wiegel, and T. Röckmann
Atmos. Meas. Tech., 8, 811–822, https://doi.org/10.5194/amt-8-811-2015, https://doi.org/10.5194/amt-8-811-2015, 2015
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Our analytical system is a promising tool for investigating the triple oxygen isotope composition of CO2 from stratospheric air samples of volumes 100ml and smaller. The method is designed for measuring air samples with CO2 mole fractions between 360 and 400ppm, and it is the first fully automated analytical system that uses CeO2 as the isotope exchange medium.
M. Riederer, J. Hübner, J. Ruppert, W. A. Brand, and T. Foken
Atmos. Meas. Tech., 7, 4237–4250, https://doi.org/10.5194/amt-7-4237-2014, https://doi.org/10.5194/amt-7-4237-2014, 2014
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The REA technique cannot be applied on grassland shortly after management without the risk of REA-flux errors due to large uncertainties of b-factors and lacking scalar similarity.
The NEE flux partitioning model based on REA measurement results is complex but can enhance results of common partitioning by considering ecosystem discrimination of 13C and wind velocity.
M. Guillevic, L. Bazin, A. Landais, C. Stowasser, V. Masson-Delmotte, T. Blunier, F. Eynaud, S. Falourd, E. Michel, B. Minster, T. Popp, F. Prié, and B. M. Vinther
Clim. Past, 10, 2115–2133, https://doi.org/10.5194/cp-10-2115-2014, https://doi.org/10.5194/cp-10-2115-2014, 2014
S. J. Sutanto, B. van den Hurk, P. A. Dirmeyer, S. I. Seneviratne, T. Röckmann, K. E. Trenberth, E. M. Blyth, J. Wenninger, and G. Hoffmann
Hydrol. Earth Syst. Sci., 18, 2815–2827, https://doi.org/10.5194/hess-18-2815-2014, https://doi.org/10.5194/hess-18-2815-2014, 2014
U. Dusek, M. Monaco, M. Prokopiou, F. Gongriep, R. Hitzenberger, H. A. J. Meijer, and T. Röckmann
Atmos. Meas. Tech., 7, 1943–1955, https://doi.org/10.5194/amt-7-1943-2014, https://doi.org/10.5194/amt-7-1943-2014, 2014
A. J. van Beelen, G. J. H. Roelofs, O. P. Hasekamp, J. S. Henzing, and T. Röckmann
Atmos. Chem. Phys., 14, 5969–5987, https://doi.org/10.5194/acp-14-5969-2014, https://doi.org/10.5194/acp-14-5969-2014, 2014
O. Peltola, A. Hensen, C. Helfter, L. Belelli Marchesini, F. C. Bosveld, W. C. M. van den Bulk, J. A. Elbers, S. Haapanala, J. Holst, T. Laurila, A. Lindroth, E. Nemitz, T. Röckmann, A. T. Vermeulen, and I. Mammarella
Biogeosciences, 11, 3163–3186, https://doi.org/10.5194/bg-11-3163-2014, https://doi.org/10.5194/bg-11-3163-2014, 2014
S. Houweling, M. Krol, P. Bergamaschi, C. Frankenberg, E. J. Dlugokencky, I. Morino, J. Notholt, V. Sherlock, D. Wunch, V. Beck, C. Gerbig, H. Chen, E. A. Kort, T. Röckmann, and I. Aben
Atmos. Chem. Phys., 14, 3991–4012, https://doi.org/10.5194/acp-14-3991-2014, https://doi.org/10.5194/acp-14-3991-2014, 2014
B. Ringeval, S. Houweling, P. M. van Bodegom, R. Spahni, R. van Beek, F. Joos, and T. Röckmann
Biogeosciences, 11, 1519–1558, https://doi.org/10.5194/bg-11-1519-2014, https://doi.org/10.5194/bg-11-1519-2014, 2014
M. E. Popa, M. K. Vollmer, A. Jordan, W. A. Brand, S. L. Pathirana, M. Rothe, and T. Röckmann
Atmos. Chem. Phys., 14, 2105–2123, https://doi.org/10.5194/acp-14-2105-2014, https://doi.org/10.5194/acp-14-2105-2014, 2014
D. Helmig, V. Petrenko, P. Martinerie, E. Witrant, T. Röckmann, A. Zuiderweg, R. Holzinger, J. Hueber, C. Thompson, J. W. C. White, W. Sturges, A. Baker, T. Blunier, D. Etheridge, M. Rubino, and P. Tans
Atmos. Chem. Phys., 14, 1463–1483, https://doi.org/10.5194/acp-14-1463-2014, https://doi.org/10.5194/acp-14-1463-2014, 2014
J. Chappellaz, C. Stowasser, T. Blunier, D. Baslev-Clausen, E. J. Brook, R. Dallmayr, X. Faïn, J. E. Lee, L. E. Mitchell, O. Pascual, D. Romanini, J. Rosen, and S. Schüpbach
Clim. Past, 9, 2579–2593, https://doi.org/10.5194/cp-9-2579-2013, https://doi.org/10.5194/cp-9-2579-2013, 2013
F. A. Haumann, A. M. Batenburg, G. Pieterse, C. Gerbig, M. C. Krol, and T. Röckmann
Atmos. Chem. Phys., 13, 9401–9413, https://doi.org/10.5194/acp-13-9401-2013, https://doi.org/10.5194/acp-13-9401-2013, 2013
M. von Hobe, S. Bekki, S. Borrmann, F. Cairo, F. D'Amato, G. Di Donfrancesco, A. Dörnbrack, A. Ebersoldt, M. Ebert, C. Emde, I. Engel, M. Ern, W. Frey, S. Genco, S. Griessbach, J.-U. Grooß, T. Gulde, G. Günther, E. Hösen, L. Hoffmann, V. Homonnai, C. R. Hoyle, I. S. A. Isaksen, D. R. Jackson, I. M. Jánosi, R. L. Jones, K. Kandler, C. Kalicinsky, A. Keil, S. M. Khaykin, F. Khosrawi, R. Kivi, J. Kuttippurath, J. C. Laube, F. Lefèvre, R. Lehmann, S. Ludmann, B. P. Luo, M. Marchand, J. Meyer, V. Mitev, S. Molleker, R. Müller, H. Oelhaf, F. Olschewski, Y. Orsolini, T. Peter, K. Pfeilsticker, C. Piesch, M. C. Pitts, L. R. Poole, F. D. Pope, F. Ravegnani, M. Rex, M. Riese, T. Röckmann, B. Rognerud, A. Roiger, C. Rolf, M. L. Santee, M. Scheibe, C. Schiller, H. Schlager, M. Siciliani de Cumis, N. Sitnikov, O. A. Søvde, R. Spang, N. Spelten, F. Stordal, O. Sumińska-Ebersoldt, A. Ulanovski, J. Ungermann, S. Viciani, C. M. Volk, M. vom Scheidt, P. von der Gathen, K. Walker, T. Wegner, R. Weigel, S. Weinbruch, G. Wetzel, F. G. Wienhold, I. Wohltmann, W. Woiwode, I. A. K. Young, V. Yushkov, B. Zobrist, and F. Stroh
Atmos. Chem. Phys., 13, 9233–9268, https://doi.org/10.5194/acp-13-9233-2013, https://doi.org/10.5194/acp-13-9233-2013, 2013
P. Sperlich, C. Buizert, T. M. Jenk, C. J. Sapart, M. Prokopiou, T. Röckmann, and T. Blunier
Atmos. Meas. Tech., 6, 2027–2041, https://doi.org/10.5194/amt-6-2027-2013, https://doi.org/10.5194/amt-6-2027-2013, 2013
V. V. Petrenko, P. Martinerie, P. Novelli, D. M. Etheridge, I. Levin, Z. Wang, T. Blunier, J. Chappellaz, J. Kaiser, P. Lang, L. P. Steele, S. Hammer, J. Mak, R. L. Langenfelds, J. Schwander, J. P. Severinghaus, E. Witrant, G. Petron, M. O. Battle, G. Forster, W. T. Sturges, J.-F. Lamarque, K. Steffen, and J. W. C. White
Atmos. Chem. Phys., 13, 7567–7585, https://doi.org/10.5194/acp-13-7567-2013, https://doi.org/10.5194/acp-13-7567-2013, 2013
L. Bazin, A. Landais, B. Lemieux-Dudon, H. Toyé Mahamadou Kele, D. Veres, F. Parrenin, P. Martinerie, C. Ritz, E. Capron, V. Lipenkov, M.-F. Loutre, D. Raynaud, B. Vinther, A. Svensson, S. O. Rasmussen, M. Severi, T. Blunier, M. Leuenberger, H. Fischer, V. Masson-Delmotte, J. Chappellaz, and E. Wolff
Clim. Past, 9, 1715–1731, https://doi.org/10.5194/cp-9-1715-2013, https://doi.org/10.5194/cp-9-1715-2013, 2013
D. Veres, L. Bazin, A. Landais, H. Toyé Mahamadou Kele, B. Lemieux-Dudon, F. Parrenin, P. Martinerie, E. Blayo, T. Blunier, E. Capron, J. Chappellaz, S. O. Rasmussen, M. Severi, A. Svensson, B. Vinther, and E. W. Wolff
Clim. Past, 9, 1733–1748, https://doi.org/10.5194/cp-9-1733-2013, https://doi.org/10.5194/cp-9-1733-2013, 2013
I. T. van der Laan-Luijkx, S. van der Laan, C. Uglietti, M. F. Schibig, R. E. M. Neubert, H. A. J. Meijer, W. A. Brand, A. Jordan, J. M. Richter, M. Rothe, and M. C. Leuenberger
Atmos. Meas. Tech., 6, 1805–1815, https://doi.org/10.5194/amt-6-1805-2013, https://doi.org/10.5194/amt-6-1805-2013, 2013
J. Schmitt, B. Seth, M. Bock, C. van der Veen, L. Möller, C. J. Sapart, M. Prokopiou, T. Sowers, T. Röckmann, and H. Fischer
Atmos. Meas. Tech., 6, 1425–1445, https://doi.org/10.5194/amt-6-1425-2013, https://doi.org/10.5194/amt-6-1425-2013, 2013
S. Walter, A. Kock, and T. Röckmann
Biogeosciences, 10, 3391–3403, https://doi.org/10.5194/bg-10-3391-2013, https://doi.org/10.5194/bg-10-3391-2013, 2013
H. C. Steen-Larsen, S. J. Johnsen, V. Masson-Delmotte, B. Stenni, C. Risi, H. Sodemann, D. Balslev-Clausen, T. Blunier, D. Dahl-Jensen, M. D. Ellehøj, S. Falourd, A. Grindsted, V. Gkinis, J. Jouzel, T. Popp, S. Sheldon, S. B. Simonsen, J. Sjolte, J. P. Steffensen, P. Sperlich, A. E. Sveinbjörnsdóttir, B. M. Vinther, and J. W. C. White
Atmos. Chem. Phys., 13, 4815–4828, https://doi.org/10.5194/acp-13-4815-2013, https://doi.org/10.5194/acp-13-4815-2013, 2013
M. Guillevic, L. Bazin, A. Landais, P. Kindler, A. Orsi, V. Masson-Delmotte, T. Blunier, S. L. Buchardt, E. Capron, M. Leuenberger, P. Martinerie, F. Prié, and B. M. Vinther
Clim. Past, 9, 1029–1051, https://doi.org/10.5194/cp-9-1029-2013, https://doi.org/10.5194/cp-9-1029-2013, 2013
M. Wendeberg, J. M. Richter, M. Rothe, and W. A. Brand
Atmos. Meas. Tech., 6, 817–822, https://doi.org/10.5194/amt-6-817-2013, https://doi.org/10.5194/amt-6-817-2013, 2013
A. Svensson, M. Bigler, T. Blunier, H. B. Clausen, D. Dahl-Jensen, H. Fischer, S. Fujita, K. Goto-Azuma, S. J. Johnsen, K. Kawamura, S. Kipfstuhl, M. Kohno, F. Parrenin, T. Popp, S. O. Rasmussen, J. Schwander, I. Seierstad, M. Severi, J. P. Steffensen, R. Udisti, R. Uemura, P. Vallelonga, B. M. Vinther, A. Wegner, F. Wilhelms, and M. Winstrup
Clim. Past, 9, 749–766, https://doi.org/10.5194/cp-9-749-2013, https://doi.org/10.5194/cp-9-749-2013, 2013
J. C. Laube, A. Keil, H. Bönisch, A. Engel, T. Röckmann, C. M. Volk, and W. T. Sturges
Atmos. Chem. Phys., 13, 2779–2791, https://doi.org/10.5194/acp-13-2779-2013, https://doi.org/10.5194/acp-13-2779-2013, 2013
N. Bândă, M. Krol, M. van Weele, T. van Noije, and T. Röckmann
Atmos. Chem. Phys., 13, 2267–2281, https://doi.org/10.5194/acp-13-2267-2013, https://doi.org/10.5194/acp-13-2267-2013, 2013
C. M. Trudinger, I. G. Enting, P. J. Rayner, D. M. Etheridge, C. Buizert, M. Rubino, P. B. Krummel, and T. Blunier
Atmos. Chem. Phys., 13, 1485–1510, https://doi.org/10.5194/acp-13-1485-2013, https://doi.org/10.5194/acp-13-1485-2013, 2013
Related subject area
Subject: Gases | Technique: Laboratory Measurement | Topic: Validation and Intercomparisons
Two new 222Rn emanation sources – a comparison study
A traceable and continuous flow calibration method for gaseous elemental mercury at low ambient concentrations
Measurements of atmospheric C10–C15 biogenic volatile organic compounds (BVOCs) with sorbent tubes
Results of a long-term international comparison of greenhouse gas and isotope measurements at the Global Atmosphere Watch (GAW) Observatory in Alert, Nunavut, Canada
Colorimetric derivatization of ambient ammonia (NH3) for detection by long-path absorption photometry
Comparison of temperature-dependent calibration methods of an instrument to measure OH and HO2 radicals using laser-induced fluorescence spectroscopy
Controlled-release testing of the static chamber methodology for direct measurements of methane emissions
Development of an International System of Units (SI)-traceable transmission curve reference material to improve the quantitation and comparability of proton-transfer-reaction mass-spectrometry measurements
Reactive uptake coefficients for multiphase reactions determined by a dynamic chamber system
Influence of CO2 adsorption on cylinders and fractionation of CO2 and air during the preparation of a standard mixture
Detection of nitrous acid in the atmospheric simulation chamber SAPHIR using open-path incoherent broadband cavity-enhanced absorption spectroscopy and extractive long-path absorption photometry
Behavior of KCl sorbent traps and KCl trapping solutions used for atmospheric mercury speciation: stability and specificity
Intercomparison of O2 ∕ N2 ratio scales among AIST, NIES, TU, and SIO based on a round-robin exercise using gravimetric standard mixtures
Characterisation of gas reference materials for underpinning atmospheric measurements of stable isotopes of nitrous oxide
An indirect-calibration method for non-target quantification of trace gases applied to a time series of fourth-generation synthetic halocarbons at the Taunus Observatory (Germany)
Revision of the World Meteorological Organization Global Atmosphere Watch (WMO/GAW) CO2 calibration scale
Comparability of calibration strategies for measuring mercury concentrations in gas emission sources and the atmosphere
Characterizing water vapour concentration dependence of commercial cavity ring-down spectrometers for continuous on-site atmospheric water vapour isotope measurements in the tropics
Implementation of an incoherent broadband cavity-enhanced absorption spectroscopy technique in an atmospheric simulation chamber for in situ NO3 monitoring: characterization and validation for kinetic studies
A portable, robust, stable, and tunable calibration source for gas-phase nitrous acid (HONO)
Optimisation of a thermal desorption–gas chromatography–mass spectrometry method for the analysis of monoterpenes, sesquiterpenes and diterpenes
SIFT-MS optimization for atmospheric trace gas measurements at varying humidity
N2O isotopocule measurements using laser spectroscopy: analyzer characterization and intercomparison
An intercomparison of CH3O2 measurements by fluorescence assay by gas expansion and cavity ring-down spectroscopy within HIRAC (Highly Instrumented Reactor for Atmospheric Chemistry)
Photoacoustic measurement with infrared band-pass filters significantly overestimates NH3 emissions from cattle houses due to volatile organic compound (VOC) interferences
Isotopic characterization of nitrogen oxides (NOx), nitrous acid (HONO), and nitrate (pNO3−) from laboratory biomass burning during FIREX
A new laser-based and ultra-portable gas sensor for indoor and outdoor formaldehyde (HCHO) monitoring
Negligible influence of livestock contaminants and sampling system on ammonia measurements with cavity ring-down spectroscopy
Preparation of primary standard mixtures for atmospheric oxygen measurements with less than 1 µmol mol−1 uncertainty for oxygen molar fractions
The interference of tetrachloromethane in the measurement of benzene in the air by a gas chromatography–photoionisation detector (GC-PID)
Evaluation of cation exchange membrane performance under exposure to high Hg0 and HgBr2 concentrations
Gravimetrically prepared carbon dioxide standards in support of atmospheric research
The importance of cylinder passivation for preparation and long-term stability of multicomponent monoterpene primary reference materials
Dynamic–gravimetric preparation of metrologically traceable primary calibration standards for halogenated greenhouse gases
The water vapour self-continuum absorption in the infrared atmospheric windows: new laser measurements near 3.3 and 2.0 µm
Interlaboratory comparison of δ13C and δD measurements of atmospheric CH4 for combined use of data sets from different laboratories
Absolute, pressure-dependent validation of a calibration-free, airborne laser hygrometer transfer standard (SEALDH-II) from 5 to 1200 ppmv using a metrological humidity generator
An intercomparison of HO2 measurements by fluorescence assay by gas expansion and cavity ring-down spectroscopy within HIRAC (Highly Instrumented Reactor for Atmospheric Chemistry)
Abundances of isotopologues and calibration of CO2 greenhouse gas measurements
Intercomparison of two cavity ring-down spectroscopy analyzers for atmospheric 13CO2 ∕ 12CO2 measurement
MIPAS database: new HNO3 line parameters at 7.6 µm validated with MIPAS satellite measurements
Challenges associated with the sampling and analysis of organosulfur compounds in air using real-time PTR-ToF-MS and offline GC-FID
Twin-cuvette measurement technique for investigation of dry deposition of O3 and PAN to plant leaves under controlled humidity conditions
Gas adsorption and desorption effects on cylinders and their importance for long-term gas records
HOx radical chemistry in oxidation flow reactors with low-pressure mercury lamps systematically examined by modeling
ACTRIS non-methane hydrocarbon intercomparison experiment in Europe to support WMO GAW and EMEP observation networks
A method for stable carbon isotope ratio and concentration measurements of ambient aromatic hydrocarbons
Instrument intercomparison of glyoxal, methyl glyoxal and NO2 under simulated atmospheric conditions
Measuring acetic and formic acid by proton-transfer-reaction mass spectrometry: sensitivity, humidity dependence, and quantifying interferences
Accurate measurements of ozone absorption cross-sections in the Hartley band
Tanita J. Ballé, Stefan Röttger, Florian Mertes, Anja Honig, Petr Kovar, Petr P. S. Otáhal, and Annette Röttger
Atmos. Meas. Tech., 17, 2055–2065, https://doi.org/10.5194/amt-17-2055-2024, https://doi.org/10.5194/amt-17-2055-2024, 2024
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Over 50 % of naturally occurring radiation exposure is due to 222Rn (progenies), but traceability of measurements to the International System of Units (SI) is lacking. To address this, two new 222Rn sources were developed to be used as calibration standards for reference instruments. These sources were investigated by comparing their estimated calibration factors for one instrument. Despite the small differences derived, all uncertainties are well within the intended target uncertainty of 10 %.
Teodor D. Andron, Warren T. Corns, Igor Živković, Saeed Waqar Ali, Sreekanth Vijayakumaran Nair, and Milena Horvat
Atmos. Meas. Tech., 17, 1217–1228, https://doi.org/10.5194/amt-17-1217-2024, https://doi.org/10.5194/amt-17-1217-2024, 2024
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Atmospheric mercury monitoring is an important activity in order to model the global trajectory of this toxic element and to assess if certain areas are polluted or not in accordance to global guidelines. One of the analysers tested in this work is globally used in this regard due to its practicality compared with other devices. Because it is only calibrated by the manufacturer at very high concentrations, we wanted to see how it performs at ambient mercury concentrations.
Heidi Hellén, Toni Tykkä, Simon Schallhart, Evdokia Stratigou, Thérèse Salameh, and Maitane Iturrate-Garcia
Atmos. Meas. Tech., 17, 315–333, https://doi.org/10.5194/amt-17-315-2024, https://doi.org/10.5194/amt-17-315-2024, 2024
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Even though online measurements of biogenic volatile organic compounds (BVOCs) are becoming more common, the use of sorbent tubes is expected to continue because they offer greater spatial coverage and no infrastructure is required for sampling. In this study the sorbent tube sampling method was optimized and evaluated for the determination of BVOCs in gas-phase samples. Tenax TA sorbent tubes were found to be suitable for the quantitative measurements of C10–C15 BVOCs.
Douglas E. J. Worthy, Michele K. Rauh, Lin Huang, Felix R. Vogel, Alina Chivulescu, Kenneth A. Masarie, Ray L. Langenfelds, Paul B. Krummel, Colin E. Allison, Andrew M. Crotwell, Monica Madronich, Gabrielle Pétron, Ingeborg Levin, Samuel Hammer, Sylvia Michel, Michel Ramonet, Martina Schmidt, Armin Jordan, Heiko Moossen, Michael Rothe, Ralph Keeling, and Eric J. Morgan
Atmos. Meas. Tech., 16, 5909–5935, https://doi.org/10.5194/amt-16-5909-2023, https://doi.org/10.5194/amt-16-5909-2023, 2023
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Network compatibility is important for inferring greenhouse gas fluxes at global or regional scales. This study is the first assessment of the measurement agreement among seven individual programs within the World Meteorological Organization community. It compares co-located flask air measurements at the Alert Observatory in Canada over a 17-year period. The results provide stronger confidence in the uncertainty estimation while using those datasets in various data interpretation applications.
Shasha Tian, Kexin Zu, Huabin Dong, Limin Zeng, Keding Lu, and Qi Chen
Atmos. Meas. Tech., 16, 5525–5535, https://doi.org/10.5194/amt-16-5525-2023, https://doi.org/10.5194/amt-16-5525-2023, 2023
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We developed an online NH3 monitoring system based on a selective colorimetric reaction and a long-path absorption photometer (SAC-LOPAP), which can run statically for a long time and be applied to the continuous online measurement of low concentrations of ambient air by optimizing the reaction conditions, adding a constant-temperature module and liquid flow controller. It is well suited for the investigation of the NH3 budget for urban to rural conditions in China.
Frank A. F. Winiberg, William J. Warman, Charlotte A. Brumby, Graham Boustead, Iustinian G. Bejan, Thomas H. Speak, Dwayne E. Heard, Daniel Stone, and Paul W. Seakins
Atmos. Meas. Tech., 16, 4375–4390, https://doi.org/10.5194/amt-16-4375-2023, https://doi.org/10.5194/amt-16-4375-2023, 2023
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OH and HO2 are key reactive intermediates in the Earth's atmosphere. Accurate measurements in either the field or simulation chambers provide a good test for chemical mechanisms. Fluorescence techniques have the appropriate sensitivity for detection but require calibration. This paper compares different methods of calibration and specifically how calibration factors vary across a temperature range relevant to atmospheric and chamber determinations.
James P. Williams, Khalil El Hachem, and Mary Kang
Atmos. Meas. Tech., 16, 3421–3435, https://doi.org/10.5194/amt-16-3421-2023, https://doi.org/10.5194/amt-16-3421-2023, 2023
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Methane is powerful greenhouse gas; thus, to reduce methane emissions, it is important that the methods used to measure methane are tested and validated. The static chamber method is an enclosure-based technique that directly measures methane emissions; however, it has not been thoroughly tested for the new variety of methane sources that it is currently being used for. We find that the static chamber method can accurately measure methane emissions under a wide range of methane emission rates.
David R. Worton, Sergi Moreno, Kieran O'Daly, and Rupert Holzinger
Atmos. Meas. Tech., 16, 1061–1072, https://doi.org/10.5194/amt-16-1061-2023, https://doi.org/10.5194/amt-16-1061-2023, 2023
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Proton-transfer-reaction mass spectrometry is widely used in the environmental, health, and food and beverage sectors. As a result, there is a need for accurate and comparable measurements. In this work we have developed a 20-component gravimetrically prepared traceable primary reference material (gas standard in a high-pressure cylinder) to enable quantitative and comparable measurements. The accuracy of all components was better than 3 %–10 % with stabilities of better than 1–2 years.
Guo Li, Hang Su, Meng Li, Uwe Kuhn, Guangjie Zheng, Lei Han, Fengxia Bao, Ulrich Pöschl, and Yafang Cheng
Atmos. Meas. Tech., 15, 6433–6446, https://doi.org/10.5194/amt-15-6433-2022, https://doi.org/10.5194/amt-15-6433-2022, 2022
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A large fraction of previous work using dynamic flow chambers was to quantify gas exchange in terms of flux or deposition/emission rate. Here, we extended the usage of this technique to examine uptake kinetics on sample surfaces. The good performance of the chamber system was validated. This technique can be further used for liquid samples and real atmospheric aerosol samples without complicated coating procedures, which complements the existing techniques in atmospheric kinetic studies.
Nobuyuki Aoki, Shigeyuki Ishidoya, Shohei Murayama, and Nobuhiro Matsumoto
Atmos. Meas. Tech., 15, 5969–5983, https://doi.org/10.5194/amt-15-5969-2022, https://doi.org/10.5194/amt-15-5969-2022, 2022
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The CO2 concentration in a cylinder is affected by carbon dioxide (CO2) adsorption to a cylinder’s internal surface and fractionation of CO2 and air in the preparation of standard mixtures. We demonstrate that the effects make the CO2 molar fractions deviate in standard mixtures prepared by diluting pure CO2 with air three times. This means that CO2 standard gases are difficult to gravimetrically prepare through multistep dilution.
Sophie Dixneuf, Albert A. Ruth, Rolf Häseler, Theo Brauers, Franz Rohrer, and Hans-Peter Dorn
Atmos. Meas. Tech., 15, 945–964, https://doi.org/10.5194/amt-15-945-2022, https://doi.org/10.5194/amt-15-945-2022, 2022
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Atmospheric chambers, like SAPHIR in Jülich (Germany), are used to experimentally simulate specific atmospheric scenarios to improve our understanding of the complex chemical reactions occurring in our atmospheres. These facilities hence require cutting-edge gas-sensing capabilities to detect trace gases at the lowest level and in a short time. One important trace gas is HONO, for which we custom-built an optical sensing setup, capable of detecting one HONO molecule in ~40 billion in 1 min.
Jan Gačnik, Igor Živković, Sergio Ribeiro Guevara, Radojko Jaćimović, Jože Kotnik, Gianmarco De Feo, Matthew A. Dexter, Warren T. Corns, and Milena Horvat
Atmos. Meas. Tech., 14, 6619–6631, https://doi.org/10.5194/amt-14-6619-2021, https://doi.org/10.5194/amt-14-6619-2021, 2021
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Atmospheric mercury and knowledge of its transformations and processes are of great importance for lowering its anthropogenic emissions. To ensure that, it is crucial to have a tested and validated measurement procedure. Since this is not always the case, we performed experiments that provided insight into commonly used atmospheric mercury sampling methods. The results showed that some sampling methods are unsuitable, and some are useful if we consider the results obtained from this work.
Nobuyuki Aoki, Shigeyuki Ishidoya, Yasunori Tohjima, Shinji Morimoto, Ralph F. Keeling, Adam Cox, Shuichiro Takebayashi, and Shohei Murayama
Atmos. Meas. Tech., 14, 6181–6193, https://doi.org/10.5194/amt-14-6181-2021, https://doi.org/10.5194/amt-14-6181-2021, 2021
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Observing the minimal long-term change in atmospheric O2 molar fraction combined with CO2 observation enables us to estimate terrestrial biospheric and oceanic CO2 uptakes separately. In this study, we firstly identified the span offset between the laboratory O2 scales using our developed high-precision standard mixtures, suggesting that the result may allow us to estimate terrestrial biospheric and oceanic CO2 uptakes precisely.
Ruth E. Hill-Pearce, Aimee Hillier, Eric Mussell Webber, Kanokrat Charoenpornpukdee, Simon O'Doherty, Joachim Mohn, Christoph Zellweger, David R. Worton, and Paul J. Brewer
Atmos. Meas. Tech., 14, 5447–5458, https://doi.org/10.5194/amt-14-5447-2021, https://doi.org/10.5194/amt-14-5447-2021, 2021
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There is currently a need for gas reference materials with well-characterised delta values for monitoring N2O amount fractions. We present work towards the preparation of gas reference materials for calibration of in-field monitoring equipment, which target the WMO-GAW data quality objectives for comparability of amount fraction and demonstrate the stability of δ15Nα, δ15Nβ and δ18O values with pressure and effects of cylinder passivation.
Fides Lefrancois, Markus Jesswein, Markus Thoma, Andreas Engel, Kieran Stanley, and Tanja Schuck
Atmos. Meas. Tech., 14, 4669–4687, https://doi.org/10.5194/amt-14-4669-2021, https://doi.org/10.5194/amt-14-4669-2021, 2021
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Synthetic halocarbons can contribute to stratospheric ozone depletion or to climate change. In many applications they have been replaced over the last years. The presented non-target analysis shows an application approach to quantify those replacements retrospectively, using recorded data of air measurements with gas chromatography coupled to time-of-flight mass spectrometry. We focus on the retrospective analysis of the fourth-generation halocarbons, detected at Taunus Observatory in Germany.
Bradley D. Hall, Andrew M. Crotwell, Duane R. Kitzis, Thomas Mefford, Benjamin R. Miller, Michael F. Schibig, and Pieter P. Tans
Atmos. Meas. Tech., 14, 3015–3032, https://doi.org/10.5194/amt-14-3015-2021, https://doi.org/10.5194/amt-14-3015-2021, 2021
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We have recently revised the carbon dioxide calibration scale used by numerous laboratories that measure atmospheric CO2. The revision follows from an improved understanding of the manometric method used to determine the absolute amount of CO2 in an atmospheric air sample. The new scale is 0.18 μmol mol−1 (ppm) greater than the previous scale at 400 ppm CO2. While this difference is small in relative terms (0.045 %), it is significant in terms of atmospheric monitoring.
Iris de Krom, Wijnand Bavius, Ruben Ziel, Elizabeth A. McGhee, Richard J. C. Brown, Igor Živković, Jan Gačnik, Vesna Fajon, Jože Kotnik, Milena Horvat, and Hugo Ent
Atmos. Meas. Tech., 14, 2317–2326, https://doi.org/10.5194/amt-14-2317-2021, https://doi.org/10.5194/amt-14-2317-2021, 2021
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To demonstrate the robustness and comparability of the novel primary mercury gas standard, the results of comparisons are presented with current calibration methods maintained, using the bell jar in combination with the Dumarey equation or NIST liquid standard reference material. The results show that the primary standard and the NIST reference material are comparable, whereas a difference of −8 % exists between results traceable to the primary standard and the Dumarey equation.
Shujiro Komiya, Fumiyoshi Kondo, Heiko Moossen, Thomas Seifert, Uwe Schultz, Heike Geilmann, David Walter, and Jost V. Lavric
Atmos. Meas. Tech., 14, 1439–1455, https://doi.org/10.5194/amt-14-1439-2021, https://doi.org/10.5194/amt-14-1439-2021, 2021
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The Amazon basin influences the atmospheric and hydrological cycles on local to global scales. To better understand how, we plan to perform continuous on-site measurements of the stable isotope composition of atmospheric water vapour. For making accurate on-site observations possible, we have investigated the performance of two commercial analysers and determined the best calibration strategy. Well calibrated, both analysers will allow us to record natural signals in the Amazon rainforest.
Axel Fouqueau, Manuela Cirtog, Mathieu Cazaunau, Edouard Pangui, Pascal Zapf, Guillaume Siour, Xavier Landsheere, Guillaume Méjean, Daniele Romanini, and Bénédicte Picquet-Varrault
Atmos. Meas. Tech., 13, 6311–6323, https://doi.org/10.5194/amt-13-6311-2020, https://doi.org/10.5194/amt-13-6311-2020, 2020
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An incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS) technique has been developed for the in situ monitoring of NO3 radicals in the CSA simulation chamber at LISA. The optical cavity allows a high sensitivity for NO3 detection up to 6 ppt for an integration time of 10 s. The technique is now fully operational and can be used to determine rate constants for fast reactions involving complex volatile organic compounds (with rate constants up to 10−10 cm3 molecule−1 s−1).
Melodie Lao, Leigh R. Crilley, Leyla Salehpoor, Teles C. Furlani, Ilann Bourgeois, J. Andrew Neuman, Andrew W. Rollins, Patrick R. Veres, Rebecca A. Washenfelder, Caroline C. Womack, Cora J. Young, and Trevor C. VandenBoer
Atmos. Meas. Tech., 13, 5873–5890, https://doi.org/10.5194/amt-13-5873-2020, https://doi.org/10.5194/amt-13-5873-2020, 2020
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Nitrous acid (HONO) is a key intermediate in the generation of oxidants and fate of nitrogen oxides in the atmosphere. High-purity calibration sources that produce stable atmospherically relevant levels under field conditions have not been made to date, reducing measurement accuracy. In this study a simple salt-coated tube humidified with water vapor is demonstrated to produce pure stable low levels of HONO, with modifications allowing the generation of higher amounts.
Aku Helin, Hannele Hakola, and Heidi Hellén
Atmos. Meas. Tech., 13, 3543–3560, https://doi.org/10.5194/amt-13-3543-2020, https://doi.org/10.5194/amt-13-3543-2020, 2020
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A thermal desorption–gas chromatography–mass spectrometry method following sorbent tube sampling was developed for the determination of terpenes in gas-phase samples. The main focus was on the analysis of diterpenes, which have been limited in study in gas-phase samples. The analytical figures of merit were fit for purpose (e.g. quantitation limits <10 pptv and reproducibility <10 % for terpenes). Diterpenes could be detected and identified in emissions from spruce and pine samples.
Ann-Sophie Lehnert, Thomas Behrendt, Alexander Ruecker, Georg Pohnert, and Susan E. Trumbore
Atmos. Meas. Tech., 13, 3507–3520, https://doi.org/10.5194/amt-13-3507-2020, https://doi.org/10.5194/amt-13-3507-2020, 2020
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Volatile organic compounds (VOCs) like scents can appear and disappear quickly. For example, when a bug starts on a tree, the tree releases VOCs that warn the trees around him. Thus, one needs instruments measuring their concentration in real time and identify which VOC is measured. In our study, we compared two instruments doing that, PTR-MS and SIFT-MS. Both work similarly, but we found that the PTR-MS can measure lower concentrations, but the SIFT-MS can identify VOCs better.
Stephen J. Harris, Jesper Liisberg, Longlong Xia, Jing Wei, Kerstin Zeyer, Longfei Yu, Matti Barthel, Benjamin Wolf, Bryce F. J. Kelly, Dioni I. Cendón, Thomas Blunier, Johan Six, and Joachim Mohn
Atmos. Meas. Tech., 13, 2797–2831, https://doi.org/10.5194/amt-13-2797-2020, https://doi.org/10.5194/amt-13-2797-2020, 2020
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The latest commercial laser spectrometers have the potential to revolutionize N2O isotope analysis. However, to do so, they must be able to produce trustworthy data. Here, we test the performance of widely used laser spectrometers for ambient air applications and identify instrument-specific dependencies on gas matrix and trace gas concentrations. We then provide a calibration workflow to facilitate the operation of these instruments in order to generate reproducible and accurate data.
Lavinia Onel, Alexander Brennan, Michele Gianella, James Hooper, Nicole Ng, Gus Hancock, Lisa Whalley, Paul W. Seakins, Grant A. D. Ritchie, and Dwayne E. Heard
Atmos. Meas. Tech., 13, 2441–2456, https://doi.org/10.5194/amt-13-2441-2020, https://doi.org/10.5194/amt-13-2441-2020, 2020
Dezhao Liu, Li Rong, Jesper Kamp, Xianwang Kong, Anders Peter S. Adamsen, Albarune Chowdhury, and Anders Feilberg
Atmos. Meas. Tech., 13, 259–272, https://doi.org/10.5194/amt-13-259-2020, https://doi.org/10.5194/amt-13-259-2020, 2020
Jiajue Chai, David J. Miller, Eric Scheuer, Jack Dibb, Vanessa Selimovic, Robert Yokelson, Kyle J. Zarzana, Steven S. Brown, Abigail R. Koss, Carsten Warneke, and Meredith Hastings
Atmos. Meas. Tech., 12, 6303–6317, https://doi.org/10.5194/amt-12-6303-2019, https://doi.org/10.5194/amt-12-6303-2019, 2019
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Isotopic analysis offers a potential tool to distinguish between sources and interpret transformation pathways of atmospheric species. We applied recently developed techniques in our lab to characterize the isotopic composition of reactive nitrogen species (NOx, HONO, HNO3, pNO3-) in fresh biomass burning emissions. Intercomparison with other techniques confirms the suitability of our methods, allowing for future applications of our techniques in a variety of environments.
Joshua D. Shutter, Norton T. Allen, Thomas F. Hanisco, Glenn M. Wolfe, Jason M. St. Clair, and Frank N. Keutsch
Atmos. Meas. Tech., 12, 6079–6089, https://doi.org/10.5194/amt-12-6079-2019, https://doi.org/10.5194/amt-12-6079-2019, 2019
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A new mid-infrared and ultra-portable formaldehyde (HCHO) sensor from Aeris Technologies is characterized and evaluated against well-established laser-induced fluorescence (LIF) instrumentation. The Aeris sensor displays linear behavior (R squared > 0.94) and shows good agreement with LIF instruments. While the compact sensor is not currently a replacement for the most sensitive research-grade instrumentation available, its sub-ppbv precision is sufficient for indoor and outdoor HCHO monitoring.
Jesper Nørlem Kamp, Albarune Chowdhury, Anders Peter S. Adamsen, and Anders Feilberg
Atmos. Meas. Tech., 12, 2837–2850, https://doi.org/10.5194/amt-12-2837-2019, https://doi.org/10.5194/amt-12-2837-2019, 2019
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We tested the performance of a cavity ring-down spectroscopy (CRDS) instrument from Picarro for measuring ammonia. Interference tests with 10 volatile organic compounds (VOCs) were conducted to find potential interference of these VOCs. Calibrations show excellent linearity over a large dynamic range of NH3 concentrations. There is negligible interference from humidity and few of the tested VOCs. Overall, the CRDS system performs well with only negligible influence from other compounds.
Nobuyuki Aoki, Shigeyuki Ishidoya, Nobuhiro Matsumoto, Takuro Watanabe, Takuya Shimosaka, and Shohei Murayama
Atmos. Meas. Tech., 12, 2631–2646, https://doi.org/10.5194/amt-12-2631-2019, https://doi.org/10.5194/amt-12-2631-2019, 2019
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Observation of atmospheric O2 requires highly precise standard gas mixtures with uncertainty of less than 1 ppm for the O2 mole fraction or 5 per meg for O2 / N2. The uncertainty had not been achieved due unknown uncertainty factors in mass determination of the filled source gases. We first developed the primary standard mixtures with 1 ppm for the O2 mole fraction or 5 per meg by identifying and reducing the unknown uncertainty factors.
Cristina Romero-Trigueros, María Esther González, Marta Doval Miñarro, and Enrique González Ferradás
Atmos. Meas. Tech., 12, 1685–1695, https://doi.org/10.5194/amt-12-1685-2019, https://doi.org/10.5194/amt-12-1685-2019, 2019
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Determining benzene in ambient air is mandatory in the European Union. The reference measuring technique is by gas chromatography (GC), and a photometric ionisation detector is recommended. This study shows that the simultaneous presence of benzene and tetrachloromethane causes a significant decrease in GC–photoionisation detector (GC-PID) readings. Given the importance of this behaviour, a possible mechanism was proposed. This study highlights the uncertainty of measuring benzene with a GC-PID.
Matthieu B. Miller, Sarrah M. Dunham-Cheatham, Mae Sexauer Gustin, and Grant C. Edwards
Atmos. Meas. Tech., 12, 1207–1217, https://doi.org/10.5194/amt-12-1207-2019, https://doi.org/10.5194/amt-12-1207-2019, 2019
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This study was undertaken to demonstrate that a cation exchange membrane (CEM) material used for sampling reactive mercury (RM) does not possess an inherent tendency to collect gaseous elemental mercury (GEM). Using a custom-built mercury vapor permeation system, we found that the CEM material has a very small GEM uptake of approximately 0.004 %, too small to create a significant artifact. We also found that a representative RM compound was collected by the CEM material with high efficiency.
Bradley D. Hall, Andrew M. Crotwell, Benjamin R. Miller, Michael Schibig, and James W. Elkins
Atmos. Meas. Tech., 12, 517–524, https://doi.org/10.5194/amt-12-517-2019, https://doi.org/10.5194/amt-12-517-2019, 2019
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We have used a one-step method for gravimetric preparation of CO2-in-air standards in aluminum cylinders. We consider both adsorption to stainless steel surfaces used in the transfer of highly pure CO2 and adsorption of CO2 to cylinder walls. This work compliments ongoing efforts to support atmospheric monitoring of CO2.
Nicholas D. C. Allen, David R. Worton, Paul J. Brewer, Celine Pascale, and Bernhard Niederhauser
Atmos. Meas. Tech., 11, 6429–6438, https://doi.org/10.5194/amt-11-6429-2018, https://doi.org/10.5194/amt-11-6429-2018, 2018
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This paper investigates the stability of trace level static terpene primary reference materials (PRMs) and how the choice of passivation affects this process. For the first time, sampling canisters that can be used in the field are tested and demonstrated to be suitable for terpene mixtures. The PRMs were compared against a novel dynamic generator system based on dilution of pure limonene vapour emitted from a permeation tube. The effect of cylinder pressure and decanting are also investigated.
Myriam Guillevic, Martin K. Vollmer, Simon A. Wyss, Daiana Leuenberger, Andreas Ackermann, Céline Pascale, Bernhard Niederhauser, and Stefan Reimann
Atmos. Meas. Tech., 11, 3351–3372, https://doi.org/10.5194/amt-11-3351-2018, https://doi.org/10.5194/amt-11-3351-2018, 2018
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We present new primary calibration scales for five halogenated greenhouse gases. The preparation method, newly applied to halocarbons, is dynamic and gravimetric
and allows the generation of reference gas mixtures at near-ambient levels (pmol mol−1). Each prepared molar fraction is traceable to the
realisation of SI units (International System of Units) and is assigned an uncertainty estimate following international guidelines.
Loic Lechevallier, Semen Vasilchenko, Roberto Grilli, Didier Mondelain, Daniele Romanini, and Alain Campargue
Atmos. Meas. Tech., 11, 2159–2171, https://doi.org/10.5194/amt-11-2159-2018, https://doi.org/10.5194/amt-11-2159-2018, 2018
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The amplitude, the temperature dependence, and the physical origin of the water vapour absorption continuum are a long standing issue in molecular spectroscopy with a direct impact in atmospheric and planetary sciences. Using highly sensitive laser spectrometers, the water self continuum has been determined with unprecedented sensitivity in infrared atmospheric transparency windows.
Taku Umezawa, Carl A. M. Brenninkmeijer, Thomas Röckmann, Carina van der Veen, Stanley C. Tyler, Ryo Fujita, Shinji Morimoto, Shuji Aoki, Todd Sowers, Jochen Schmitt, Michael Bock, Jonas Beck, Hubertus Fischer, Sylvia E. Michel, Bruce H. Vaughn, John B. Miller, James W. C. White, Gordon Brailsford, Hinrich Schaefer, Peter Sperlich, Willi A. Brand, Michael Rothe, Thomas Blunier, David Lowry, Rebecca E. Fisher, Euan G. Nisbet, Andrew L. Rice, Peter Bergamaschi, Cordelia Veidt, and Ingeborg Levin
Atmos. Meas. Tech., 11, 1207–1231, https://doi.org/10.5194/amt-11-1207-2018, https://doi.org/10.5194/amt-11-1207-2018, 2018
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Isotope measurements are useful for separating different methane sources. However, the lack of widely accepted standards and calibration methods for stable carbon and hydrogen isotopic ratios of methane in air has caused significant measurement offsets among laboratories. We conducted worldwide interlaboratory comparisons, surveyed the literature and assessed them systematically. This study may be of help in future attempts to harmonize data sets of isotopic composition of atmospheric methane.
Bernhard Buchholz and Volker Ebert
Atmos. Meas. Tech., 11, 459–471, https://doi.org/10.5194/amt-11-459-2018, https://doi.org/10.5194/amt-11-459-2018, 2018
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This paper describes the absolute validation of the novel, calibration-free SEALDH-II hygrometer at a traceable humidity generator. During 23 days of permanent operation, 15 H2O mole fractions levels (5–1200 ppmv) at 6 gas pressures (65–950 hPa) were validated. With this validation, SEALDH-II is the first metrologically validated humidity transfer standard which links several scientific airborne and laboratory measurement campaigns to the international metrological water vapor scale.
Lavinia Onel, Alexander Brennan, Michele Gianella, Grace Ronnie, Ana Lawry Aguila, Gus Hancock, Lisa Whalley, Paul W. Seakins, Grant A. D. Ritchie, and Dwayne E. Heard
Atmos. Meas. Tech., 10, 4877–4894, https://doi.org/10.5194/amt-10-4877-2017, https://doi.org/10.5194/amt-10-4877-2017, 2017
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Hydroperoxy (HO2) radicals are key intermediates participating in a rapid chemical cycling at the centre of the tropospheric oxidation. Fluorescence assay by gas expansion (FAGE) technique is the most commonly used for the HO2 measurements in the atmosphere. However, FAGE is an indirect technique, requiring calibration. This work finds a good agreement between the indirect FAGE method and the direct cavity ring-down spectroscopy method and hence validates FAGE and the FAGE calibration method.
Pieter P. Tans, Andrew M. Crotwell, and Kirk W. Thoning
Atmos. Meas. Tech., 10, 2669–2685, https://doi.org/10.5194/amt-10-2669-2017, https://doi.org/10.5194/amt-10-2669-2017, 2017
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We describe a new CO2 calibration system for the Central Calibration Laboratory of the World Meteorological Organization Global Atmosphere Watch program. The system uses two laser spectroscopic instruments to measure the three major CO2 isotopologues individually. We account for isotopic differences between standards in the calibration hierarchy when assigning CO2 mole fraction, eliminating bias due to variations in the isotopic composition.
Jiaping Pang, Xuefa Wen, Xiaomin Sun, and Kuan Huang
Atmos. Meas. Tech., 9, 3879–3891, https://doi.org/10.5194/amt-9-3879-2016, https://doi.org/10.5194/amt-9-3879-2016, 2016
Agnès Perrin, Jean-Marie Flaud, Marco Ridolfi, Jean Vander Auwera, and Massimo Carlotti
Atmos. Meas. Tech., 9, 2067–2076, https://doi.org/10.5194/amt-9-2067-2016, https://doi.org/10.5194/amt-9-2067-2016, 2016
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Improved line positions and intensities have been generated for the 7.6 µm spectral region of nitric acid, relying on a recent laboratory reinvestigation and comparisons of HNO3 volume mixing ratios retrieved from Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) radiances in the 11 and 7.6 µm regions. The much improved consistency of line intensities in both regions will make it possible to use them simultaneously to retrieve atmospheric HNO3.
Véronique Perraud, Simone Meinardi, Donald R. Blake, and Barbara J. Finlayson-Pitts
Atmos. Meas. Tech., 9, 1325–1340, https://doi.org/10.5194/amt-9-1325-2016, https://doi.org/10.5194/amt-9-1325-2016, 2016
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Gas phase organosulfur compounds in air serve as precursors of particles which impact human health, visibility, and climate. We compare here two different approaches to measuring these compounds, one an online mass spectrometry technique and the other canister sampling followed by offline analysis by gas chromatography. We show that each approach has its own advantages and limitations in measuring these compounds in complex mixtures, including some artifacts due to reactions on surfaces.
Shang Sun, Alexander Moravek, Lisa von der Heyden, Andreas Held, Matthias Sörgel, and Jürgen Kesselmeier
Atmos. Meas. Tech., 9, 599–617, https://doi.org/10.5194/amt-9-599-2016, https://doi.org/10.5194/amt-9-599-2016, 2016
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We present a dynamic twin-cuvette system for quantifying the trace gas exchange fluxes between plants and the atmosphere under controlled temperature, light, and humidity conditions. We found out that at a relative humidity of 40 %, the deposition velocity ratio of O3 and PAN was determined to be 0.45. At that humidity, the O3-deposition to the plant leaves was found to be only controlled by leaf stomata. For PAN, an additional resistance inhibited the uptake of PAN by the leaves.
M. C. Leuenberger, M. F. Schibig, and P. Nyfeler
Atmos. Meas. Tech., 8, 5289–5299, https://doi.org/10.5194/amt-8-5289-2015, https://doi.org/10.5194/amt-8-5289-2015, 2015
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Adsorption/desorption effects of trace gases in gas cylinders were investigated. Our measurements indicate a rather strong effect on steel cylinders for CO2 that becomes easily visible through enhanced concentrations for low (<20 bars) gas pressure. Much smaller effects are observed for CO and CH4. Significantly smaller effects are measured for all gas species investigated on aluminium cylinders. Careful selection of gas cylinders for high-precision calibration purposes is recommended.
Z. Peng, D. A. Day, H. Stark, R. Li, J. Lee-Taylor, B. B. Palm, W. H. Brune, and J. L. Jimenez
Atmos. Meas. Tech., 8, 4863–4890, https://doi.org/10.5194/amt-8-4863-2015, https://doi.org/10.5194/amt-8-4863-2015, 2015
C. C. Hoerger, A. Claude, C. Plass-Duelmer, S. Reimann, E. Eckart, R. Steinbrecher, J. Aalto, J. Arduini, N. Bonnaire, J. N. Cape, A. Colomb, R. Connolly, J. Diskova, P. Dumitrean, C. Ehlers, V. Gros, H. Hakola, M. Hill, J. R. Hopkins, J. Jäger, R. Junek, M. K. Kajos, D. Klemp, M. Leuchner, A. C. Lewis, N. Locoge, M. Maione, D. Martin, K. Michl, E. Nemitz, S. O'Doherty, P. Pérez Ballesta, T. M. Ruuskanen, S. Sauvage, N. Schmidbauer, T. G. Spain, E. Straube, M. Vana, M. K. Vollmer, R. Wegener, and A. Wenger
Atmos. Meas. Tech., 8, 2715–2736, https://doi.org/10.5194/amt-8-2715-2015, https://doi.org/10.5194/amt-8-2715-2015, 2015
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The performance of 20 European laboratories involved in long-term non-methane hydrocarbon (NMHC) measurements was assessed with respect to ACTRIS and GAW data quality objectives. The participants were asked to measure both a 30-component NMHC mixture in nitrogen and whole air. The NMHCs were analysed either by GC-FID or GC-MS. Most systems performed well for the NMHC in nitrogen, whereas in air more scatter was observed. Reasons for this are explained in the paper.
A. Kornilova, S. Moukhtar, M. Saccon, L. Huang, W. Zhang, and J. Rudolph
Atmos. Meas. Tech., 8, 2301–2313, https://doi.org/10.5194/amt-8-2301-2015, https://doi.org/10.5194/amt-8-2301-2015, 2015
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A technique for compound specific analysis of stable carbon isotope ratios and concentration of ambient volatile organic compounds (VOC) is presented. It is based on selective VOC sampling onto adsorbent filled cartridges. Examples of measurements conducted demonstrate that the ability to make accurate measurements in air with low VOC mixing ratios is important to avoid bias from an overrepresentation of samples that are strongly impacted by recent emissions.
R. Thalman, M. T. Baeza-Romero, S. M. Ball, E. Borrás, M. J. S. Daniels, I. C. A. Goodall, S. B. Henry, T. Karl, F. N. Keutsch, S. Kim, J. Mak, P. S. Monks, A. Muñoz, J. Orlando, S. Peppe, A. R. Rickard, M. Ródenas, P. Sánchez, R. Seco, L. Su, G. Tyndall, M. Vázquez, T. Vera, E. Waxman, and R. Volkamer
Atmos. Meas. Tech., 8, 1835–1862, https://doi.org/10.5194/amt-8-1835-2015, https://doi.org/10.5194/amt-8-1835-2015, 2015
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Measurements of α-dicarbonyl compounds, like glyoxal (CHOCHO) and methyl glyoxal (CH3C(O)CHO), are informative about the rate of hydrocarbon oxidation, oxidative capacity, and secondary organic aerosol (SOA) formation in the atmosphere. We have compared nine instruments and seven techniques to measure α-dicarbonyl, using simulation chamber facilities in the US and Europe. We assess our understanding of calibration, precision, accuracy and detection limits, as well as possible sampling biases.
M. Baasandorj, D. B. Millet, L. Hu, D. Mitroo, and B. J. Williams
Atmos. Meas. Tech., 8, 1303–1321, https://doi.org/10.5194/amt-8-1303-2015, https://doi.org/10.5194/amt-8-1303-2015, 2015
J. Viallon, S. Lee, P. Moussay, K. Tworek, M. Petersen, and R. I. Wielgosz
Atmos. Meas. Tech., 8, 1245–1257, https://doi.org/10.5194/amt-8-1245-2015, https://doi.org/10.5194/amt-8-1245-2015, 2015
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Short summary
Isotope measurements in atmospheric CH4 are performed since more than 3 decades. However, standard gases to harmonize global measurements are not available to this day. We designed two methods to calibrate a suite of 8 CH4 gases with a wide range in isotopic composition to the VPDB and VSMOW scales with high precision and accuracy. Synthetic air mixtures with ~2 ppm of calibrated CH4 can be provided to the community by the ISOLAB of the Max Planck Institute for Biogeochemistry in Jena, Germany.
Isotope measurements in atmospheric CH4 are performed since more than 3 decades. However,...
