197 results on '"Bozem, Heiko"'
Search Results
2. A signature of aged biogenic compounds detected from airborne VOC measurements in the high arctic atmosphere in March/April 2018
- Author
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Holzinger, Rupert, Eppers, Oliver, Adachi, Kouji, Bozem, Heiko, Hartmann, Markus, Herber, Andreas, Koike, Makoto, Millet, Dylan B., Moteki, Nobuhiro, Ohata, Sho, Stratmann, Frank, and Yoshida, Atsushi
- Published
- 2023
- Full Text
- View/download PDF
3. Overview paper: New insights into aerosol and climate in the Arctic
- Author
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Abbatt, Jonathan PD, Leaitch, W Richard, Aliabadi, Amir A, Bertram, Allan K, Blanchet, Jean-Pierre, Boivin-Rioux, Aude, Bozem, Heiko, Burkart, Julia, Chang, Rachel YW, Charette, Joannie, Chaubey, Jai P, Christensen, Robert J, Cirisan, Ana, Collins, Douglas B, Croft, Betty, Dionne, Joelle, Evans, Greg J, Fletcher, Christopher G, Galí, Martí, Ghahremaninezhad, Roghayeh, Girard, Eric, Gong, Wanmin, Gosselin, Michel, Gourdal, Margaux, Hanna, Sarah J, Hayashida, Hakase, Herber, Andreas B, Hesaraki, Sareh, Hoor, Peter, Huang, Lin, Hussherr, Rachel, Irish, Victoria E, Keita, Setigui A, Kodros, John K, Köllner, Franziska, Kolonjari, Felicia, Kunkel, Daniel, Ladino, Luis A, Law, Kathy, Levasseur, Maurice, Libois, Quentin, Liggio, John, Lizotte, Martine, Macdonald, Katrina M, Mahmood, Rashed, Martin, Randall V, Mason, Ryan H, Miller, Lisa A, Moravek, Alexander, Mortenson, Eric, Mungall, Emma L, Murphy, Jennifer G, Namazi, Maryam, Norman, Ann-Lise, O'Neill, Norman T, Pierce, Jeffrey R, Russell, Lynn M, Schneider, Johannes, Schulz, Hannes, Sharma, Sangeeta, Si, Meng, Staebler, Ralf M, Steiner, Nadja S, Thomas, Jennie L, von Salzen, Knut, Wentzell, Jeremy JB, Willis, Megan D, Wentworth, Gregory R, Xu, Jun-Wei, and Yakobi-Hancock, Jacqueline D
- Subjects
Climate Action ,Astronomical and Space Sciences ,Atmospheric Sciences ,Meteorology & Atmospheric Sciences - Abstract
Motivated by the need to predict how the Arctic atmosphere will change in a warming world, this article summarizes recent advances made by the research consortium NETCARE (Network on Climate and Aerosols: Addressing Key Uncertainties in Remote Canadian Environments) that contribute to our fundamental understanding of Arctic aerosol particles as they relate to climate forcing. The overall goal of NETCARE research has been to use an interdisciplinary approach encompassing extensive field observations and a range of chemical transport, earth system, and biogeochemical models. Several major findings and advances have emerged from NETCARE since its formation in 2013. (1) Unexpectedly high summertime dimethyl sulfide (DMS) levels were identified in ocean water (up to 75 nM) and the overlying atmosphere (up to 1 ppbv) in the Canadian Arctic Archipelago (CAA). Furthermore, melt ponds, which are widely prevalent, were identified as an important DMS source (with DMS concentrations of up to 6 nM and a potential contribution to atmospheric DMS of 20 % in the study area). (2) Evidence of widespread particle nucleation and growth in the marine boundary layer was found in the CAA in the summertime, with these events observed on 41 % of days in a 2016 cruise. As well, at Alert, Nunavut, particles that are newly formed and grown under conditions of minimal anthropogenic influence during the months of July and August are estimated to contribute 20 % to 80 % of the 30-50 nm particle number density. DMS-oxidation-driven nucleation is facilitated by the presence of atmospheric ammonia arising from seabird-colony emissions, and potentially also from coastal regions, tundra, and biomass burning. Via accumulation of secondary organic aerosol (SOA), a significant fraction of the new particles grow to sizes that are active in cloud droplet formation. Although the gaseous precursors to Arctic marine SOA remain poorly defined, the measured levels of common continental SOA precursors (isoprene and monoterpenes) were low, whereas elevated mixing ratios of oxygenated volatile organic compounds (OVOCs) were inferred to arise via processes involving the sea surface microlayer. (3) The variability in the vertical distribution of black carbon (BC) under both springtime Arctic haze and more pristine summertime aerosol conditions was observed. Measured particle size distributions and mixing states were used to constrain, for the first time, calculations of aerosol-climate interactions under Arctic conditions. Aircraft- and ground-based measurements were used to better establish the BC source regions that supply the Arctic via long-range transport mechanisms, with evidence for a dominant springtime contribution from eastern and southern Asia to the middle troposphere, and a major contribution from northern Asia to the surface. (4) Measurements of ice nucleating particles (INPs) in the Arctic indicate that a major source of these particles is mineral dust, likely derived from local sources in the summer and long-range transport in the spring. In addition, INPs are abundant in the sea surface microlayer in the Arctic, and possibly play a role in ice nucleation in the atmosphere when mineral dust concentrations are low. (5) Amongst multiple aerosol components, BC was observed to have the smallest effective deposition velocities to high Arctic snow (0.03 cm s1).
- Published
- 2019
4. New insights into aerosol and climate in the Arctic
- Author
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Abbatt, Jonathan PD, Leaitch, W Richard, Aliabadi, Amir A, Bertram, Alan K, Blanchet, Jean-Pierre, Boivin-Rioux, Aude, Bozem, Heiko, Burkart, Julia, Chang, Rachel YW, Charette, Joannie, Chaubey, Jai P, Christensen, Robert J, Cirisan, Ana, Collins, Douglas B, Croft, Betty, Dionne, Joelle, Evans, Greg J, Fletcher, Christopher G, Ghahremaninezhad, Roghayeh, Girard, Eric, Gong, Wanmin, Gosselin, Michel, Gourdal, Margaux, Hanna, Sarah J, Hayashida, Hakase, Herber, Andreas B, Hesaraki, Sareh, Hoor, Peter, Huang, Lin, Hussherr, Rachel, Irish, Victoria E, Keita, Setigui A, Kodros, John K, Köllner, Franziska, Kolonjari, Felicia, Kunkel, Daniel, Ladino, Luis A, Law, Kathy, Levasseur, Maurice, Libois, Quentin, Liggio, John, Lizotte, Martine, Macdonald, Katrina M, Mahmood, Rashed, Martin, Randall V, Mason, Ryan H, Miller, Lisa A, Moravek, Alexander, Mortenson, Eric, Mungall, Emma L, Murphy, Jennifer G, Namazi, Maryam, Norman, Ann-Lise, O'Neill, Norman T, Pierce, Jeffrey R, Russell, Lynn M, Schneider, Johannes, Schulz, Hannes, Sharma, Sangeeta, Si, Meng, Staebler, Ralf M, Steiner, Nadja S, Galí, Martí, Thomas, Jennie L, von Salzen, Knut, Wentzell, Jeremy JB, Willis, Megan D, Wentworth, Gregory R, Xu, Jun-Wei, and Yakobi-Hancock, Jacqueline D
- Subjects
Earth Sciences ,Atmospheric Sciences ,Climate Action ,Life Below Water ,Astronomical and Space Sciences ,Meteorology & Atmospheric Sciences ,Atmospheric sciences ,Climate change science - Abstract
Abstract. Motivated by the need to predict how the Arctic atmosphere will change in a warming world, this article summarizes recent advances made by the research consortium NETCARE (Network on Climate and Aerosols: Addressing Key Uncertainties in Remote Canadian Environments) that contribute to our fundamental understanding of Arctic aerosol particles as they relate to climate forcing. The overall goal of NETCARE research has been to use an interdisciplinary approach encompassing extensive field observations and a range of chemical transport, earth system, and biogeochemical models. Several major findings and advances have emerged from NETCARE since its formation in 2013 . (1) Unexpectedly high summertime dimethyl sulfide (DMS) levels were identified in ocean water and the overlying atmosphere in the Canadian Arctic Archipelago (CAA). Furthermore, melt ponds, which are widely prevalent, were identified as an important DMS source. (2) Evidence was found of widespread particle nucleation and growth in the marine boundary layer in the CAA in the summertime. DMS-oxidation-driven nucleation is facilitated by the presence of atmospheric ammonia arising from sea bird colony emissions, and potentially also from coastal regions, tundra, and biomass burning. Via accumulation of secondary organic material (SOA), a significant fraction of the new particles grow to sizes that are active in cloud droplet formation. Although the gaseous precursors to Arctic marine SOA remain poorly defined, the measured levels of common continental SOA precursors (isoprene and monoterpenes) were low, whereas elevated mixing ratios of oxygenated volatile organic compounds were inferred to arise via processes involving the sea surface microlayer. (3) The variability in the vertical distribution of black carbon (BC) under both springtime Arctic haze and more pristine summertime aerosol conditions was observed. Measured particle size distributions and mixing states were used to constrain, for the first time, calculations of aerosol–climate interactions under Arctic conditions. Aircraft- and ground-based measurements were used to better establish the BC source regions that supply the Arctic via long-range transport mechanisms. (4) Measurements of ice nucleating particles (INPs) in the Arctic indicate that a major source of these particles is mineral dust, likely derived from local sources in the summer and long-range transport in the spring. In addition, INPs are abundant in the sea surface microlayer in the Arctic, and possibly play a role in ice nucleation in the atmosphere when mineral dust concentrations are low. (5) Amongst multiple aerosol components, BC was observed to have the smallest effective deposition velocities to high Arctic snow.
- Published
- 2018
5. Overview: quasi-Lagrangian observations of Arctic air mass transformations – introduction and initial results of the HALO–(AC)3 aircraft campaign.
- Author
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Wendisch, Manfred, Crewell, Susanne, Ehrlich, André, Herber, Andreas, Kirbus, Benjamin, Lüpkes, Christof, Mech, Mario, Abel, Steven J., Akansu, Elisa F., Ament, Felix, Aubry, Clémantyne, Becker, Sebastian, Borrmann, Stephan, Bozem, Heiko, Brückner, Marlen, Clemen, Hans-Christian, Dahlke, Sandro, Dekoutsidis, Georgios, Delanoë, Julien, and De La Torre Castro, Elena
- Subjects
AIR masses ,CLOUDINESS ,WATER vapor ,CIRRUS clouds ,ARCTIC climate ,SEA ice ,ICE clouds - Abstract
Global warming is amplified in the Arctic. However, numerical models struggle to represent key processes that determine Arctic weather and climate. To collect data that help to constrain the models, the HALO–(AC) 3 aircraft campaign was conducted over the Norwegian and Greenland seas, the Fram Strait, and the central Arctic Ocean in March and April 2022. The campaign focused on one specific challenge posed by the models, namely the reasonable representation of transformations of air masses during their meridional transport into and out of the Arctic via northward moist- and warm-air intrusions (WAIs) and southward marine cold-air outbreaks (CAOs). Observations were made over areas of open ocean, the marginal sea ice zone, and the central Arctic sea ice. Two low-flying and one long-range, high-altitude research aircraft were flown in colocated formation whenever possible. To follow the air mass transformations, a quasi-Lagrangian flight strategy using trajectory calculations was realized, enabling us to sample the same moving-air parcels twice along their trajectories. Seven distinct WAI and 12 CAO cases were probed. From the quasi-Lagrangian measurements, we have quantified the diabatic heating/cooling and moistening/drying of the transported air masses. During CAOs, maximum values of 3 K h -1 warming and 0.3 g kg -1 h -1 moistening were obtained below 1 km altitude. From the observations of WAIs, diabatic cooling rates of up to 0.4 K h -1 and a moisture loss of up to 0.1 g kg -1 h -1 from the ground to about 5.5 km altitude were derived. Furthermore, the development of cloud macrophysical (cloud-top height and horizontal cloud cover) and microphysical (liquid water path, precipitation, and ice index) properties along the southward pathways of the air masses were documented during CAOs, and the moisture budget during a specific WAI event was estimated. In addition, we discuss the statistical frequency of occurrence of the different thermodynamic phases of Arctic low-level clouds, the interaction of Arctic cirrus clouds with sea ice and water vapor, and the characteristics of microphysical and chemical properties of Arctic aerosol particles. Finally, we provide a proof of concept to measure mesoscale divergence and subsidence in the Arctic using data from dropsondes released during the flights. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
6. A comprehensive in-situ and remote sensing data set collected during the HALO–(AC)3 aircraft campaign.
- Author
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Ehrlich, André, Crewell, Susanne, Herber, Andreas, Klingebiel, Marcus, Lüpkes, Christof, Mech, Mario, Becker, Sebastian, Borrmann, Stephan, Bozem, Heiko, Buschmann, Matthias, Clemen, Hans-Christian, Castro, Elena De La Torre, Dorff, Henning, Dupuy, Regis, Eppers, Oliver, Ewald, Florian, George, Geet, Giez, Andreas, Grawe, Sarah, and Gourbeyre, Christophe
- Subjects
PANGAEA (Supercontinent) ,RESEARCH aircraft ,AIR masses ,HALOS (Meteorology) ,SEA ice ,TRACE gases ,SERVER farms (Computer network management) - Abstract
The HALO–(AC)
3 aircraft campaign was carried out in March and April 2022 over the Norwegian and Greenland Seas, the Fram Strait, and the central Arctic Ocean. Three research aircraft, the High Altitude and Long Range Research Aircraft (HALO), Polar 5, and Polar 6, performed 54 partly coordinated research flights on 23 flight days over areas of open ocean, the marginal sea ice zone (MIZ), and the central Arctic sea ice. The general objective of the research flights was to quantify the evolution of air mass properties during moist and warm air intrusions (WAIs) and cold air outbreaks (CAOs). To gain a comprehensive data set, the three aircraft followed different strategies. HALO was equipped with active and passive remote sensing instruments and dropsondes to cover the regional evolution of cloud and thermodynamic processes. Polar 5 carried a similar remote sensing payload as HALO, and Polar 6 was instrumented with in-situ cloud, aerosol, and trace gas instruments focusing on the initial air mass transformation close to the MIZ. The processed, calibrated, and validated data are published in the World Data Center PANGAEA as instrument-separated data subsets and listed in aircraft-separated collections for HALO (Ehrlich et al., 2024a), Polar 5 (Mech et al., 2024a), and Polar 6 (Herber et al., 2024). A detailed overview of the available data sets is provided here. Furthermore, the campaign-specific instrument setup, the data processing, and data quality are summarized. Based on measurements conducted during a specific CAO, it is shown that the scientific analysis of the HALO– (AC)3 data benefits from the coordinated operation of the three aircraft. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
7. Preparation of low-concentration H2 test gas mixtures in ambient air for calibration of H2 sensors.
- Author
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Karbach, Niklas, Höhler, Lisa, Hoor, Peter, Bozem, Heiko, Bobrowski, Nicole, and Hoffmann, Thorsten
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TRACE gases ,ELECTROCHEMICAL sensors ,CALIBRATION gases ,GAS detectors ,DETECTORS ,CALIBRATION ,GAS mixtures - Abstract
Using electrochemical gas sensors for quantitative measurements of trace gas components in ambient air introduces several challenges, of which interference, drift and aging of the sensor are the most significant. Frequent and precise calibration as well as thorough characterization of the sensor helps to achieve reliable and repeatable results. We therefore propose the use of a simple, lightweight and inexpensive setup to produce hydrogen calibration gases with precisely known concentrations in ambient air. The hydrogen is produced by electrolysis with electric current monitoring, and the output can be set to any value between ∼ 3 and ∼ 11 µgH2min-1. With a dilution flow of 500 mL min -1 , for example, this results in a concentration range from ∼ 70 up to ∼ 240 ppm, but concentrations significantly below or above this range can also be covered with accordingly modified dilution flows. This setup can be used not only for calibration, but also for thorough and long-term characterization of electrochemical gas sensors to evaluate sensitivity, zero voltage and response time over extended periods of time. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
8. Supplementary material to "Preparation of low concentration H2 test gas mixtures in ambient air for calibration of H2 sensors"
- Author
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Karbach, Niklas, primary, Höhler, Lisa, additional, Hoor, Peter, additional, Bozem, Heiko, additional, Bobrwoski, Nicole, additional, and Hoffmann, Thorsten, additional
- Published
- 2024
- Full Text
- View/download PDF
9. Preparation of low concentration H2 test gas mixtures in ambient air for calibration of H2 sensors
- Author
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Karbach, Niklas, primary, Höhler, Lisa, additional, Hoor, Peter, additional, Bozem, Heiko, additional, Bobrwoski, Nicole, additional, and Hoffmann, Thorsten, additional
- Published
- 2024
- Full Text
- View/download PDF
10. Overview: Quasi-Lagrangian observations of Arctic air mass transformations – Introduction and initial results of the HALO–(AC)3 aircraft campaign
- Author
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Wendisch, Manfred, primary, Crewell, Susanne, additional, Ehrlich, André, additional, Herber, Andreas, additional, Kirbus, Benjamin, additional, Lüpkes, Christof, additional, Mech, Mario, additional, Abel, Steven J., additional, Akansu, Elisa F., additional, Ament, Felix, additional, Aubry, Clémantyne, additional, Becker, Sebastian, additional, Borrmann, Stephan, additional, Bozem, Heiko, additional, Brückner, Marlen, additional, Clemen, Hans-Christian, additional, Dahlke, Sandro, additional, Dekoutsidis, Georgios, additional, Delanoë, Julien, additional, De La Torre Castro, Elena, additional, Dorff, Henning, additional, Dupuy, Regis, additional, Eppers, Oliver, additional, Ewald, Florian, additional, George, Geet, additional, Gorodetskaya, Irina V., additional, Grawe, Sarah, additional, Groß, Silke, additional, Hartmann, Jörg, additional, Henning, Silvia, additional, Hirsch, Lutz, additional, Jäkel, Evelyn, additional, Joppe, Philipp, additional, Jourdan, Olivier, additional, Jurányi, Zsofia, additional, Karalis, Michail, additional, Kellermann, Mona, additional, Klingebiel, Marcus, additional, Lonardi, Michael, additional, Lucke, Johannes, additional, Luebke, Anna, additional, Maahn, Maximilian, additional, Maherndl, Nina, additional, Maturilli, Marion, additional, Mayer, Bernhard, additional, Mayer, Johanna, additional, Mertes, Stephan, additional, Michaelis, Janosch, additional, Michalkov, Michel, additional, Mioche, Guillaume, additional, Moser, Manuel, additional, Müller, Hanno, additional, Neggers, Roel, additional, Ori, Davide, additional, Paul, Daria, additional, Paulus, Fiona, additional, Pilz, Christian, additional, Pithan, Felix, additional, Pöhlker, Mira, additional, Pörtge, Veronika, additional, Ringel, Maximilian, additional, Risse, Nils, additional, Roberts, Gregory C., additional, Rosenburg, Sophie, additional, Röttenbacher, Johannes, additional, Rückert, Janna, additional, Schäfer, Michael, additional, Schäfer, Jonas, additional, Schemannn, Vera, additional, Schirmacher, Imke, additional, Schmidt, Jörg, additional, Schmidt, Sebastian, additional, Schneider, Johannes, additional, Schnitt, Sabrina, additional, Schwarz, Anja, additional, Siebert, Holger, additional, Sodemann, Harald, additional, Sperzel, Tim, additional, Spreen, Gunnar, additional, Stevens, Bjorn, additional, Stratmann, Frank, additional, Svensson, Gunilla, additional, Tatzelt, Christian, additional, Tuch, Thomas, additional, Vihma, Timo, additional, Voigt, Christiane, additional, Volkmer, Lea, additional, Walbröl, Andreas, additional, Weber, Anna, additional, Wehner, Birgit, additional, Wetzel, Bruno, additional, Wirth, Martin, additional, and Zinner, Tobias, additional
- Published
- 2024
- Full Text
- View/download PDF
11. POLSTRACC
- Author
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Oelhaf, Hermann, Sinnhuber, Björn-Martin, Woiwode, Wolfgang, Bönisch, Harald, Bozem, Heiko, Engel, Andreas, Fix, Andreas, Friedl-Vallon, Felix, Grooß, Jens-Uwe, Hoor, Peter, Johansson, Sören, Jurkat-Witschas, Tina, Kaufmann, Stefan, Krämer, Martina, Krause, Jens, Kretschmer, Erik, Lörks, Dominique, Marsing, Andreas, Orphal, Johannes, Pfeilsticker, Klaus, Pitts, Michael, Poole, Lamont, Preusse, Peter, Rapp, Markus, Riese, Martin, Rolf, Christian, Ungermann, Jörn, Voigt, Christiane, Volk, C. Michael, Wirth, Martin, Zahn, Andreas, and Ziereis, Helmut
- Published
- 2019
12. THE ARCTIC CLOUD PUZZLE : Using ACLOUD/PASCAL Multiplatform Observations to Unravel the Role of Clouds and Aerosol Particles in Arctic Amplification
- Author
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Wendisch, Manfred, Macke, Andreas, Ehrlich, André, Lüpkes, Christof, Mech, Mario, Chechin, Dmitry, Dethloff, Klaus, Velasco, Carola Barrientos, Bozem, Heiko, Brückner, Marlen, Clemen, Hans-Christian, Crewell, Susanne, Donth, Tobias, Dupuy, Regis, Ebell, Kerstin, Egerer, Ulrike, Engelmann, Ronny, Engler, Christa, Eppers, Oliver, Gehrmann, Martin, Gong, Xianda, Gottschalk, Matthias, Gourbeyre, Christophe, Griesche, Hannes, Hartmann, Jörg, Hartmann, Markus, Heinold, Bernd, Herber, Andreas, Herrmann, Hartmut, Heygster, Georg, Hoor, Peter, Jafariserajehlou, Soheila, Jäkel, Evelyn, Järvinen, Emma, Jourdan, Olivier, Kästner, Udo, Kecorius, Simonas, Knudsen, Erlend M., Köllner, Franziska, Kretzschmar, Jan, Lelli, Luca, Leroy, Delphine, Maturilli, Marion, Mei, Linlu, Mertes, Stephan, Mioche, Guillaume, Neuber, Roland, Nicolaus, Marcel, Nomokonova, Tatiana, Notholt, Justus, Palm, Mathias, van Pinxteren, Manuela, Quaas, Johannes, Richter, Philipp, Ruiz-Donoso, Elena, Schäfer, Michael, Schmieder, Katja, Schnaiter, Martin, Schneider, Johannes, Schwarzenböck, Alfons, Seifert, Patric, Shupe, Matthew D., Siebert, Holger, Spreen, Gunnar, Stapf, Johannes, Stratmann, Frank, Vogl, Teresa, Welti, André, Wex, Heike, Wiedensohler, Alfred, Zanatta, Marco, and Zeppenfeld, Sebastian
- Published
- 2019
13. POLSTRACC: Airborne Experiment for Studying the Polar Stratosphere in a Changing Climate with the High Altitude and Long Range Research Aircraft (HALO): The POLSTRACC mission provided a wealth of data on the structure and comparison of the Arctic lower-most stratosphere and upper troposphere during the extraordinarily cold winter 2015/16
- Author
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Oelhaf, Hermann, Sinnhuber, Bjorn-Martin, Woiwode, Wolfgang, Bonisch, Harald, Bozem, Heiko, Engel, Andreas, Fix, Andreas, Friedl-Vallon, Felix, Grooss, Jens-Uwe, Hoor, Peter, Johansson, Soren, Jurkat-Witschas, Tina, Kaufmann, Stefan, Kramer, Martina, Krause, Jens, Kretschmer, Erik, Lorks, Dominique, Marsing, Andreas, Orphal, Johannes, Pfeilsticker, Klaus, Pitts, Michael, Poole, Lamont, Preusse, Peter, Rapp, Markus, Riese, Martin, Rolf, Christian, Ungermann, Jorn, Voigt, Christian, Volk, C. Michael, Wirth, Martin, Zahn, Andreas, and Ziereis, Helmut
- Subjects
Troposphere -- Research -- Analysis ,Aircraft -- Research -- Analysis ,Middle atmosphere -- Research -- Analysis ,Business ,Earth sciences - Abstract
ABSTRACT The Polar Stratosphere in a Changing Climate (POLSTRACC) mission employed the German High Altitude and Long Range Research Aircraft (HALO). The payload comprised an innovative combination of remote sensing [...]
- Published
- 2019
- Full Text
- View/download PDF
14. Modelling Regional Air Quality in the Canadian Arctic: Simulation of an Arctic Summer Field Campaign
- Author
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Gong, Wanmin, Beagley, Stephen, Zhang, Junhua, Staebler, Ralf, Aliabadi, Amir A., Sharma, Sangeeta, Tarasick, David, Burkart, Julia, Willis, Megan, Wentworth, Greg, Murphy, Jennifer, Bozem, Heiko, Koellner, Franziska, Schneider, Johannes, Herber, Andreas, Richard Leaitch, W., Abbatt, Jon, Mensink, Clemens, editor, and Kallos, George, editor
- Published
- 2018
- Full Text
- View/download PDF
15. Overview: Quasi-Lagrangian observations of Arctic air mass transformations – Introduction and initial results of the HALO–(AC)3 aircraft campaign.
- Author
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Wendisch, Manfred, Crewell, Susanne, Ehrlich, André, Herber, Andreas, Kirbus, Benjamin, Lüpkes, Christof, Mech, Mario, Abel, Steven J., Akansu, Elisa F., Ament, Felix, Aubry, Clémantyne, Becker, Sebastian, Borrmann, Stephan, Bozem, Heiko, Brückner, Marlen, Clemen, Hans-Christian, Dahlke, Sandro, Dekoutsidis, Georgios, Delanoë, Julien, and Castro, Elena De La Torre
- Subjects
AIR masses ,MODEL airplanes ,SEA ice ,WATER vapor ,ATMOSPHERIC models ,RESEARCH aircraft - Abstract
The global warming is amplified in the Arctic. To collect data that help to constrain weather and climate models, which often do not realistically represent the enhanced Arctic warming, the HALO-(AC)³ aircraft campaign was conducted in March and April 2022 over the Norwegian and Greenland Seas, the Fram Strait, and the central Arctic Ocean. Observations were made over areas of open ocean, the marginal sea ice zone, and the central Arctic sea ice. Two low-flying and one long-range, high-altitude research aircraft have been employed. Whenever possible, the three aircraft were flown in collocated formation. The campaign focused on one specific challenge posed by the models: The reasonable representation of transformations of air masses during their meridional transport into (northward by moist and warm air intrusions, WAIs) and out of (southward via marine cold air outbreaks, CAOs) the Arctic. To observe the air mass transformations, a quasi-Lagrangian flight strategy using trajectory calculations was realized enabling to sample the moving air mass parcels twice along their trajectories. Eight distinct WAI and 12 CAO cases were probed extensively. From the quasi-Lagrangian measurements, we have derived the diabatic heating and moistening of the moving air masses during CAOs and WAIs, the development of cloud macrophysical and microphysical properties along the southward pathways of the air masses during CAOs, and the moisture budget of WAIs. As an example result, we have obtained typical values of the surface-driven diabatic heating between 1–3 K h
-1 and of the near-surface moistening between 0.05–0.3 g kg-1 h-1 within the lowest about 0.5 km. From the observations of WAIs, a weak diabatic cooling of up to 0.4 K h-1 and a moisture loss of up to 0.1 g kg-1 h-1 from the ground to about 5 km altitude were derived. In addition, we discuss the frequency of occurrence of the different thermodynamic phases of Arctic low-level clouds, the interaction of Arctic cirrus with sea ice, water vapor, and aerosol particles, and the characteristic microphysical and chemical properties of Arctic aerosol particles. Finally, we provide proof of a concept to measure mesoscale divergence and subsidence in the Arctic using data from dropsondes released during circular flight patterns. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
16. Preparation of low concentration H2 test gas mixtures in ambient air for calibration of H2 sensors.
- Author
-
Karbach, Niklas, Höhler, Lisa, Hoor, Peter, Bozem, Heiko, Bobrwoski, Nicole, and Hoffmann, Thorsten
- Subjects
TRACE gases ,ELECTROCHEMICAL sensors ,CALIBRATION gases ,GAS detectors ,DETECTORS ,CALIBRATION ,GAS mixtures ,MIXTURES - Abstract
Using electrochemical gas sensors for quantitative measurements of trace gas components in ambient air introduces several challenges, of which interference, drift and aging of the sensor are the most significant. Frequent and precise calibration as well as thorough characterization of the sensor helps to achieve reliable and repeatable results. We therefore propose the use of a simple, lightweight and inexpensive setup to produce hydrogen calibration gases with precisely known concentrations in ambient air. The hydrogen is produced by electrolysis with electric current monitoring and the output can be set to any value between ~3 µg
H2 /min and ~11 µgH2 /min. With a dilution flow of 500 mL/min, for example, this results in a concentration range from ~70 ppm up to ~240 ppm, but concentrations significantly below or above this range can also be covered with accordingly modified dilution flows. This setup can be used not only for calibration, but also for thorough and long-term characterization of electrochemical gas sensors to evaluate sensitivity, zero voltage and response time over extended periods of time. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
17. Massive ozone production from South American wild fires observed during SOUTHTRAC
- Author
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Peter Hoor, Daniel Kunkel, Lachnitt Hans-Christoph, Bozem Heiko, Bense Vera, Smoydzin Linda, Riese Martin, Zahn Andreas, and Ziereis Helmut
- Abstract
During the SOUTHTRAC mission, which took place in September and November 2019, the Germanresearch aircraft HALO performed several cross sections from the equator to the southern tip ofsouth America. The flight legs were flown along the coast of Brazil at typical altitudes of 13-14 km.During the northbound flight on October, 7th 2019 massive enhancements of pollutants wereobserved at these altitudes. Notably, in-situ observations show continuously elevated CO valuesexceeding 200 ppbv over a flight distance of more than 1000 km. These massive enhancements wereaccompanied by strongly elevated NO and NOy as well as CO2 and could be attributed to the large firesin South America during this time. These fires occurred in conjunction with convection overArgentina and Brazil, which led to efficient vertical transport. Lagrangian and chemical model analysisconfirmed the potential impact of convection and biomass burning to the observed enhancements ofozone and pollutants.Comparing the tracer observations to previous flights in exactly the same region three weeks earlier,we could estimate the ozone production due to the biomass burning. Weestimate an ozone production in the polluted air masses of almost 30%of the observed ozone mixing ratio. Given the large extent of the polluted area over 15 degrees oflatitude this may have an impact on the local energy budget of the tropopause region.
- Published
- 2023
18. N2O Temporal Variability from the Middle Troposphere to the Middle Stratosphere Based on Airborne and Balloon-Borne Observations during the Period 1987–2018
- Author
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Krysztofiak, Gisèle, primary, Catoire, Valéry, additional, Dudok de Wit, Thierry, additional, Kinnison, Douglas E., additional, Ravishankara, A. R., additional, Brocchi, Vanessa, additional, Atlas, Elliot, additional, Bozem, Heiko, additional, Commane, Róisín, additional, D’Amato, Francesco, additional, Daube, Bruce, additional, Diskin, Glenn S., additional, Engel, Andreas, additional, Friedl-Vallon, Felix, additional, Hintsa, Eric, additional, Hurst, Dale F., additional, Hoor, Peter, additional, Jegou, Fabrice, additional, Jucks, Kenneth W., additional, Kleinböhl, Armin, additional, Küllmann, Harry, additional, Kort, Eric A., additional, McKain, Kathryn, additional, Moore, Fred L., additional, Obersteiner, Florian, additional, Ramos, Yenny Gonzalez, additional, Schuck, Tanja, additional, Toon, Geoffrey C., additional, Viciani, Silvia, additional, Wetzel, Gerald, additional, Williams, Jonathan, additional, and Wofsy, Steven C., additional
- Published
- 2023
- Full Text
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19. Rapid gas measurements in volcanic plumes with UAVs: online and offline measurements of various trace gases with light UAVs
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Karbach, Niklas, primary, Geil, Bastien, additional, Blumenroth, Jonas, additional, Bozem, Heiko, additional, von Glahn, Christian, additional, Hoor, Peter, additional, Bobrowski, Nicole, additional, and Hoffmann, Thorsten, additional
- Published
- 2023
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20. Comparison of inorganic chlorine in the Antarctic and Arctic lowermost stratosphere by separate late winter aircraft measurements
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Jesswein, Markus, Bozem, Heiko, Lachnitt, Hans-Christoph, Hoor, Peter, Wagenhäuser, Thomas, Keber, Timo, Schuck, Tanja, and Engel, Andreas
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Chemistry ,Physics ,QC1-999 ,QD1-999 - Abstract
Stratospheric inorganic chlorine (Cly) is predominantly released from long-lived chlorinated source gases and, to a small extent, very short-lived chlorinated substances. Cly includes the reservoir species (HCl and ClONO2) and active chlorine species (i.e., ClOx). The active chlorine species drive catalytic cycles that deplete ozone in the polar winter stratosphere. This work presents calculations of inorganic chlorine (Cly) derived from chlorinated source gas measurements on board the High Altitude and Long Range Research Aircraft (HALO) during the Southern Hemisphere Transport, Dynamic and Chemistry (SouthTRAC) campaign in austral late winter and early spring 2019. Results are compared to Cly in the Northern Hemisphere derived from measurements of the POLSTRACC-GW-LCYCLE-SALSA (PGS) campaign in the Arctic winter of 2015/2016. A scaled correlation was used for PGS data, since not all source gases were measured. Using the SouthTRAC data, Cly from a scaled correlation was compared to directly determined Cly and agreed well. An air mass classification based on in situ N2O measurements allocates the measurements to the vortex, the vortex boundary region, and midlatitudes. Although the Antarctic vortex was weakened in 2019 compared to previous years, Cly reached 1687±19 ppt at 385 K; therefore, up to around 50 % of total chlorine was found in inorganic form inside the Antarctic vortex, whereas only 15 % of total chlorine was found in inorganic form in the southern midlatitudes. In contrast, only 40 % of total chlorine was found in inorganic form in the Arctic vortex during PGS, and roughly 20 % was found in inorganic form in the northern midlatitudes. Differences inside the two vortices reach as much as 540 ppt, with more Cly in the Antarctic vortex in 2019 than in the Arctic vortex in 2016 (at comparable distance to the local tropopause). To our knowledge, this is the first comparison of inorganic chlorine within the Antarctic and Arctic polar vortices. Based on the results of these two campaigns, the differences in Cly inside the two vortices are substantial and larger than the inter-annual variations previously reported for the Antarctic.
- Published
- 2021
21. Modelling Regional Air Quality in the Canadian Arctic: Simulation of an Arctic Summer Field Campaign
- Author
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Gong, Wanmin, primary, Beagley, Stephen, additional, Zhang, Junhua, additional, Staebler, Ralf, additional, Aliabadi, Amir A., additional, Sharma, Sangeeta, additional, Tarasick, David, additional, Burkart, Julia, additional, Willis, Megan, additional, Wentworth, Greg, additional, Murphy, Jennifer, additional, Bozem, Heiko, additional, Koellner, Franziska, additional, Schneider, Johannes, additional, Herber, Andreas, additional, Richard Leaitch, W., additional, and Abbatt, Jon, additional
- Published
- 2017
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22. N 2 O Temporal Variability from the Middle Troposphere to the Middle Stratosphere Based on Airborne and Balloon-Borne Observations during the Period 1987–2018.
- Author
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Krysztofiak, Gisèle, Catoire, Valéry, Dudok de Wit, Thierry, Kinnison, Douglas E., Ravishankara, A. R., Brocchi, Vanessa, Atlas, Elliot, Bozem, Heiko, Commane, Róisín, D'Amato, Francesco, Daube, Bruce, Diskin, Glenn S., Engel, Andreas, Friedl-Vallon, Felix, Hintsa, Eric, Hurst, Dale F., Hoor, Peter, Jegou, Fabrice, Jucks, Kenneth W., and Kleinböhl, Armin
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STRATOSPHERE ,OZONE layer depletion ,NITROUS oxide ,TROPOSPHERE ,ATMOSPHERIC chemistry ,TROPOSPHERIC aerosols ,ATMOSPHERE ,FOURIER transform spectrometers ,TROPOSPHERIC chemistry - Abstract
Nitrous oxide (N
2 O) is the fourth most important greenhouse gas in the atmosphere and is considered the most important current source gas emission for global stratospheric ozone depletion (O3 ). It has natural and anthropogenic sources, mainly as an unintended by-product of food production activities. This work examines the identification and quantification of trends in the N2 O concentration from the middle troposphere to the middle stratosphere (MTMS) by in situ and remote sensing observations. The temporal variability of N2 O is addressed using a comprehensive dataset of in situ and remote sensing N2 O concentrations based on aircraft and balloon measurements in the MTMS from 1987 to 2018. We determine N2 O trends in the MTMS, based on observations. This consistent dataset was also used to study the N2 O seasonal cycle to investigate the relationship between abundances and its emission sources through zonal means. The results show a long-term increase in global N2 O concentration in the MTMS with an average of 0.89 ± 0.07 ppb/yr in the troposphere and 0.96 ± 0.15 ppb/yr in the stratosphere, consistent with 0.80 ppb/yr derived from ground-based measurements and 0.799 ± 0.024 ppb/yr ACE-FTS (Atmospheric Chemistry Experiment Fourier Transform Spectrometer) satellite measurements. [ABSTRACT FROM AUTHOR]- Published
- 2023
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23. Possible controls on Arctic clouds by natural aerosols from long-range transport of biogenic emissions and ozone depletion events
- Author
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Holzinger, Rupert, primary, Eppers, Oliver, additional, Adachi, Kouji, additional, Bozem, Heiko, additional, Hartmann, Markus, additional, Herber, Andreas, additional, Koike, Makoto, additional, Millet, Dylan, additional, Ohata, Sho, additional, and Stratmann, Frank, additional
- Published
- 2022
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24. Revisiting the ExTL: From tracer correlations to dynamical processes
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Hoor, Peter, primary, Kaluza, Thorsten, additional, Kunkel, Daniel, additional, Lachnitt, Hans-Christoph, additional, Amelie, Mayer, additional, Bense, Vera, additional, Bozem, Heiko, additional, and Joppe, Philipp, additional
- Published
- 2022
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25. Supplementary material to "Possible controls on Arctic clouds by natural aerosols from long-range transport of biogenic emissions and ozone depletion events"
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Holzinger, Rupert, primary, Eppers, Oliver, additional, Adachi, Kouji, additional, Bozem, Heiko, additional, Hartmann, Markus, additional, Herber, Andreas, additional, Koike, Makoto, additional, Millet, Dylan B., additional, Moteki, Nobuhiro, additional, Ohata, Sho, additional, Stratmann, Frank, additional, and Yoshida, Atsushi, additional
- Published
- 2022
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26. Arctic black carbon during PAMARCMiP 2018 and previous aircraft experiments in spring
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Ohata, Sho, primary, Koike, Makoto, additional, Yoshida, Atsushi, additional, Moteki, Nobuhiro, additional, Adachi, Kouji, additional, Oshima, Naga, additional, Matsui, Hitoshi, additional, Eppers, Oliver, additional, Bozem, Heiko, additional, Zanatta, Marco, additional, and Herber, Andreas B., additional
- Published
- 2021
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- View/download PDF
27. Comparison of Inorganic Chlorine in the Southern Hemispheric lowermost stratosphere during Late Winter 2019
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Jesswein, Markus, primary, Bozem, Heiko, additional, Lachnitt, Hans-Christoph, additional, Hoor, Peter, additional, Wagenhäuser, Thomas, additional, Keber, Timo, additional, Schuck, Tanja, additional, and Engel, Andreas, additional
- Published
- 2021
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- View/download PDF
28. Supplementary material to "Comparison of Inorganic Chlorine in the Southern Hemispheric lowermost stratosphere during Late Winter 2019"
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Jesswein, Markus, primary, Bozem, Heiko, additional, Lachnitt, Hans-Christoph, additional, Hoor, Peter, additional, Wagenhäuser, Thomas, additional, Keber, Timo, additional, Schuck, Tanja, additional, and Engel, Andreas, additional
- Published
- 2021
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- View/download PDF
29. Chemical composition and source attribution of sub-micrometre aerosol particles in the summertime Arctic lower troposphere
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Köllner, Franziska, primary, Schneider, Johannes, additional, Willis, Megan D., additional, Schulz, Hannes, additional, Kunkel, Daniel, additional, Bozem, Heiko, additional, Hoor, Peter, additional, Klimach, Thomas, additional, Helleis, Frank, additional, Burkart, Julia, additional, Leaitch, W. Richard, additional, Aliabadi, Amir A., additional, Abbatt, Jonathan P. D., additional, Herber, Andreas B., additional, and Borrmann, Stephan, additional
- Published
- 2021
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- View/download PDF
30. Winter and summer characterization of biogenic enantiomeric monoterpenes and anthropogenic BTEX compounds at a Mediterranean Stone Pine forest site
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Song, Wei, Williams, Jonathan, Yassaa, Noureddine, Martinez, Monica, Carnero, José Antonio Adame, Hidalgo, Pablo J., Bozem, Heiko, and Lelieveld, Jos
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- 2011
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31. Airborne in situ tracer and age of air observations in the UTLS during the rare Antarctic sudden stratospheric warming 2019
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Rau, Andrea, primary, Lauther, Valentin, additional, Hader, Fridolin, additional, Cvetkova, Svetlana, additional, Volk, C. Michael, additional, Hoor, Peter, additional, Bense, Vera, additional, and Bozem, Heiko, additional
- Published
- 2021
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32. POLSTRACC: Airborne Experiment for Studying the Polar Stratosphere in a Changing Climate with the High Altitude and Long Range Research Aircraft (HALO)
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Oelhaf, Hermann, Sinnhuber, Björn-Martin, Woiwode, Wolfgang, Bönisch, Harald, Bozem, Heiko, Engel, Andreas, Fix, Andreas, Friedl-Vallon, Felix, Grooß, Jens-Uwe, Hoor, Peter, Johansson, Sören, Jurkat-Witschas, Tina, Kaufmann, Stefan, Krämer, Martina, Krause, Jens, Kretschmer, Erik, Lörks, Dominique, Marsing, Andreas, Orphal, Johannes, Pfeilsticker, Klaus, Pitts, Michael, Poole, Lamont, Preusse, Peter, Rapp, Markus, Riese, Martin, Rolf, Christian, Ungermann, Jörn, Voigt, Christiane, Volk, C. Michael, Wirth, Martin, Zahn, Andreas, and Ziereis, Helmut
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POLSTRACC ,Halo ,Long-lived trace gases ,Institut für Physik der Atmosphäre ,Lidar ,ddc:550 ,remote sensing PSC ,Atmosphärische Spurenstoffe ,Wolkenphysik - Abstract
The Polar Stratosphere in a Changing Climate (POLSTRACC) mission employed the German High Altitude and Long Range Research Aircraft (HALO). The payload comprised an innovative combination of remote sensing and in situ instruments. The in situ instruments provided high-resolution observations of cirrus and polar stratospheric clouds (PSCs), a large number of reactive and long-lived trace gases, and temperature at the aircraft level. Information above and underneath the aircraft level was achieved by remote sensing instruments as well as dropsondes. The mission took place from 8 December 2015 to 18 March 2016, covering the extremely cold late December to early February period and the time around the major warming in the beginning of March. In 18 scientific deployments, 156 flight hours were conducted, covering latitudes from 25° to 87°N and maximum altitudes of almost 15 km, and reaching potential temperature levels of up to 410 K. Highlights of results include 1) new aspects of transport and mixing in the Arctic upper troposphere–lower stratosphere (UTLS), 2) detailed analyses of special dynamical features such as tropopause folds, 3) observations of extended PSCs reaching sometimes down to HALO flight levels at 13–14 km, 4) observations of particulate NOy and vertical redistribution of gas-phase NOy in the lowermost stratosphere (LMS), 5) significant chlorine activation and deactivation in the LMS along with halogen source gas observations, and 6) the partitioning and budgets of reactive chlorine and bromine along with a detailed study of the efficiency of ClOx/BrOx ozone loss cycle. Finally, we quantify—based on our results—the ozone loss in the 2015/16 winter and address the question of how extraordinary this Arctic winter was.
- Published
- 2019
33. Possible controls on Arctic clouds by natural aerosols from long-range transport of biogenic emissions and ozone depletion events.
- Author
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Holzinger, Rupert, Eppers, Oliver, Adachi, Kouji, Bozem, Heiko, Hartmann, Markus, Herber, Andreas, Koike, Makoto, Millet, Dylan B., Moteki, Nobuhiro, Ohata, Sho, Stratmann, Frank, and Yoshida, Atsushi
- Abstract
During the PAMARCMiP 2018 campaign (March and April 2018) a proton-transfer-reaction mass spectrometer (PTR-MS) was deployed onboard the POLAR 5 research aircraft and sampled the high Arctic atmosphere under Arctic haze conditions. More than 100 compounds exhibited levels above 1 pmol/mol in at least 25% of the measurements. We used back trajectories and acetone mixing ratios to identify periods with and without long-range transport from continental sources. Air masses with continental influence contained elevated levels of compounds associated with aged biogenic emissions and anthropogenic pollution (e.g., methanol, peroxyacetylnitrate (PAN), acetone, acetic acid, methylethylketone (MEK), proprionic acid, and pentanone). Almost half of all positively detected compounds (>100) in the High Arctic atmosphere can be associated with terpene oxidation products. This may constitute a signature of biogenic terpenes and their oxidation products on the high Arctic atmosphere. Many of these compounds will condense and produce biogenic secondary organic aerosol (SOA) - a natural source of organic aerosol (OA) in addition to the aerosols that can be associated with pollution. Therefore, we hypothesize that biogenic SOA may have exerted significant control over the complex system of aerosols, clouds and longwave radiation in the pre-industrial Arctic winter, even though their role is likely marginal under contemporary polluted Arctic haze conditions. However, biogenic SOA may become an important 40 factor in the futRure again, if biogenic emissions are enhanced due to climate change and if polluting technologies are phased out in the future. During two flights, surface ozone depletion events (ODE) were observed that coincided with enhanced levels of acetone, and methylethylketone. There is evidence that ODEs may also be associated with the emission of biogenic ice-nucleating particles (INP) because the filter samples taken during these two flights exhibited enhanced levels of highly active INP. Both these processes, INP production in association with ozone depletion events, and the transport of biogenic SOA could require corrections in estimates of Arctic change. If the preindustrial effects from these natural factors was stronger than is thought, subsequent climate changes over the Arctic may be larger than currently assumed. [ABSTRACT FROM AUTHOR]
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- 2022
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34. Vertical profiles of light absorption and scattering associated with black carbon particle fractions in the springtime Arctic above 79° N
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Leaitch, W. Richard, primary, Kodros, John K., additional, Willis, Megan D., additional, Hanna, Sarah, additional, Schulz, Hannes, additional, Andrews, Elisabeth, additional, Bozem, Heiko, additional, Burkart, Julia, additional, Hoor, Peter, additional, Kolonjari, Felicia, additional, Ogren, John A., additional, Sharma, Sangeeta, additional, Si, Meng, additional, von Salzen, Knut, additional, Bertram, Allan K., additional, Herber, Andreas, additional, Abbatt, Jonathan P. D., additional, and Pierce, Jeffrey R., additional
- Published
- 2020
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35. Chemical composition and source attribution of submicron aerosol particles in the summertime Arctic lower troposphere
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Köllner, Franziska, primary, Schneider, Johannes, additional, Willis, Megan D., additional, Schulz, Hannes, additional, Kunkel, Daniel, additional, Bozem, Heiko, additional, Hoor, Peter, additional, Klimach, Thomas, additional, Helleis, Frank, additional, Burkart, Julia, additional, Leaitch, W. Richard, additional, Aliabadi, Amir A., additional, Abbatt, Jonathan P. D., additional, Herber, Andreas B., additional, and Borrmann, Stephan, additional
- Published
- 2020
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- View/download PDF
36. Supplementary material to "Chemical composition and source attribution of submicron aerosol particles in the summertime Arctic lower troposphere"
- Author
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Köllner, Franziska, primary, Schneider, Johannes, additional, Willis, Megan D., additional, Schulz, Hannes, additional, Kunkel, Daniel, additional, Bozem, Heiko, additional, Hoor, Peter, additional, Klimach, Thomas, additional, Helleis, Frank, additional, Burkart, Julia, additional, Leaitch, W. Richard, additional, Aliabadi, Amir A., additional, Abbatt, Jonathan P. D., additional, Herber, Andreas B., additional, and Borrmann, Stephan, additional
- Published
- 2020
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37. Empirical ozone production in the subtropical UTLS from South American biomass burning during SOUTHTRAC
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Hoor, Peter, primary, Kunkel, Daniel, additional, Lachnitt, Hans-Christoph, additional, Bozem, Heiko, additional, Bense, Vera, additional, Grooß, Jens-Uwe, additional, Ungermann, Jörn, additional, Engel, Andreas, additional, Zahn, Andreas, additional, Ziereis, Helmut, additional, Friedl-Vallon, Felix, additional, Johansson, Sören, additional, Sinnhuber, Björn-Martin, additional, Riese, Martin, additional, and Rapp, Markus, additional
- Published
- 2020
- Full Text
- View/download PDF
38. Transport processes in the lowermost stratosphere - interhemispheric differences from trace gas observations during WISE and SouthTRAC
- Author
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Bense, Vera, primary, Hoor, Peter, additional, Kluschat, Björn, additional, Bozem, Heiko, additional, Kunkel, Daniel, additional, Lachnitt, Hans-Christoph, additional, Kaluza, Thorsten, additional, Joppe, Philipp, additional, Büttner, Maximilian, additional, Krause, Jens, additional, Engel, Andreas, additional, Zahn, Andreas, additional, Grooß, Jens-Uwe, additional, Riese, Martin, additional, Rapp, Markus, additional, and Sinnhuber, Björn-Martin, additional
- Published
- 2020
- Full Text
- View/download PDF
39. Airborne survey of trace gases and aerosols over the Southern Baltic Sea: from clean marine boundary layer to shipping corridor effect
- Author
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Zanatta, Marco, primary, Bozem, Heiko, additional, Köllner, Franziska, additional, Schneider, Johannes, additional, Kunkel, Daniel, additional, Hoor, Peter, additional, De Faria, Julia, additional, Petzold, Andreas, additional, Bundke, Ulrich, additional, Hayden, Katherine, additional, Staebler, Ralf M., additional, Schulz, Hannes, additional, and Herber, Andreas B., additional
- Published
- 2020
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- View/download PDF
40. Characterization of transport regimes and the polar dome during Arctic spring and summer using in situ aircraft measurements
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Bozem, Heiko, primary, Hoor, Peter, additional, Kunkel, Daniel, additional, Köllner, Franziska, additional, Schneider, Johannes, additional, Herber, Andreas, additional, Schulz, Hannes, additional, Leaitch, W. Richard, additional, Aliabadi, Amir A., additional, Willis, Megan D., additional, Burkart, Julia, additional, and Abbatt, Jonathan P. D., additional
- Published
- 2019
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41. A comprehensive in situ and remote sensing data set from the Arctic CLoud Observations Using airborne measurements during polar Day (ACLOUD) campaign
- Author
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Ehrlich, André, primary, Wendisch, Manfred, additional, Lüpkes, Christof, additional, Buschmann, Matthias, additional, Bozem, Heiko, additional, Chechin, Dmitri, additional, Clemen, Hans-Christian, additional, Dupuy, Régis, additional, Eppers, Olliver, additional, Hartmann, Jörg, additional, Herber, Andreas, additional, Jäkel, Evelyn, additional, Järvinen, Emma, additional, Jourdan, Olivier, additional, Kästner, Udo, additional, Kliesch, Leif-Leonard, additional, Köllner, Franziska, additional, Mech, Mario, additional, Mertes, Stephan, additional, Neuber, Roland, additional, Ruiz-Donoso, Elena, additional, Schnaiter, Martin, additional, Schneider, Johannes, additional, Stapf, Johannes, additional, and Zanatta, Marco, additional
- Published
- 2019
- Full Text
- View/download PDF
42. Comparison of Inorganic Chlorine in the Southern Hemispheric lowermost stratosphere during Late Winter 2019.
- Author
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Jesswein, Markus, Bozem, Heiko, Lachnitt, Hans-Christoph, Hoor, Peter, Wagenhäuser, Thomas, Keber, Timo, Schuck, Tanja, and Engel, Andreas
- Abstract
Inorganic chlorine (Cl
y ) is the sum of the degradation products of long-lived chlorinated source gases. These include the reservoir species (HCl and ClONO2 ) and active chlorine species (i.e. ClOx ). The active chlorine species drive catalytic cycles that deplete ozone in the polar winter stratosphere. This work presents calculations of inorganic chlorine (Cly ) derived from chlorinated source gas measurements on board the High Altitude and Long Range Research Aircraft (HALO) during the Southern hemisphere Transport, Dynamic and Chemistry (SouthTRAC) campaign in late winter and early spring 2019. Results are compared to Cly of the Northern Hemisphere derived from measurements of the POLSTRACC-GW-LCYCLE-SALSA (PGS) campaign in the Arctic winter of 2015/2016. A scaled correlation was used for PGS data, since not all source gases were measured. Cly from a scaled correlation was compared to directly determined Cly and agreed well. An air mass classification based on in situ N2 O measurements allocates the measurements to the vortex, the vortex boundary region, and mid-latitudes. Although the Antarctic vortex was weakened in 2019 compared to previous years, Cly reached 1687±20 ppt at 385 K, therefore up to around 50% of total chlorine could be found in inorganic form inside the Antarctic vortex, whereas only 15% of total chlorine could be found in inorganic form in the southern mid-latitudes. In contrast, only 40% of total chlorine could be found in inorganic form in the Arctic vortex during PGS and roughly 20% in the northern mid-latitudes. Differences inside the respective vortex reaches up to 565 ppt more Cly in the Antarctic vortex 2019 than in the Arctic vortex 2016 (at comparable distance to the local tropopause). As far as is known, this is the first comparison of inorganic chlorine within the respective polar vortex. Based on the results of these two campaigns, the difference of Cly inside the respective vortex is significant and larger than reported inter annual variations. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
43. New insights into aerosol and climate in the Arctic
- Author
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Abbatt, Jonathan P. D., Leaitch, W. Richard, Aliabadi, Amir A., Bertram, Alan K., Blanchet, Jean-Pierre, Boivin-Rioux, Aude, Bozem, Heiko, Burkart, Julia, Chang, Rachel Y. W., Charette, Joannie, Chaubey, Jai P., Christensen, Robert J., Cirisan, Ana, Collins, Douglas B., Croft, Betty, Dionne, Joelle, Evans, Greg J., Fletcher, Christopher G., Ghahremaninezhad, Roghayeh, Girard, Eric, Gong, Wanmin, Gosselin, Michel, Gourdal, Margaux, Hanna, Sarah J., Hayashida, Hakase, Herber, Andreas B., Hesaraki, Sareh, Hoor, Peter, Huang, Lin, Hussherr, Rachel, Irish, Victoria E., Keita, Setigui A., Kodros, John K., Köllner, Franziska, Kolonjari, Felicia, Kunkel, Daniel, Ladino, Luis A., Law, Kathy S., Levasseur, Maurice, Libois, Quentin, Liggio, John, Lizotte, Martine, Macdonald, Katrina M., Mahmood, Rashed, Martin, Randall V., Mason, Ryan H., Miller, Lisa A., Moravek, Alexander, Mortenson, Eric, Mungall, Emma L., Murphy, Jennifer G., Namazi, Maryam, Norman, Ann-Lise, O'Neill, Norman T., Pierce, Jeffrey R., Russell, Lynn M., Schneider, Johannes, Schulz, Hannes, Sharma, Sangeeta, Si, Meng, Staebler, Ralf M., Steiner, Nadja S., Gali, Marti, Thomas, Jennie L., von Salzen, Knut, Wentzell, Jeremy J. B., Willis, Megan D., Wentworth, Gregory R., Xu, Jun-Wei, Yakobi-Hancock, Jacqueline D., Department of Chemistry [University of Toronto], University of Toronto, Environment and Climate Change Canada, School of Engineering [Guelph], University of Guelph, Department of Chemistry [Vancouver] (UBC Chemistry), University of British Columbia (UBC), Département des sciences de la terre et de l'atmosphère [Montréal] (SCTA), Université du Québec à Montréal = University of Québec in Montréal (UQAM), Institut des Sciences de la MER de Rimouski (ISMER), Université du Québec à Rimouski (UQAR), Institute for Atmospheric Physics [Mainz] (IPA), Johannes Gutenberg - Universität Mainz (JGU), Aerosol Physics and Environmental Physics [Vienna], University of Vienna [Vienna], Department of Physics and Atmospheric Science [Halifax], Dalhousie University [Halifax], Department of Chemistry [Lewisburg], Bucknell University, Department of Chemical Engineering and Applied Chemistry (CHEM ENG), Department of Geography and Environmental Management [Waterloo], University of Waterloo [Waterloo], Departement de Biologie [Québec], Université Laval [Québec] (ULaval), School of Earth and Ocean Sciences [Victoria] (SEOS), University of Victoria [Canada] (UVIC), Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Centre d'Applications et de Recherches en TELédétection (CARTEL), Université de Sherbrooke [Sherbrooke], Department of Atmospheric Science [Fort Collins], Colorado State University [Fort Collins] (CSU), Particle Chemistry Department [Mainz], Max Planck Institute for Chemistry (MPIC), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Centro de Ciencias de la Atmosfera [Mexico], Universidad Nacional Autónoma de México (UNAM), TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Department of Biology [Québec], Air Quality Processes Research Section, Canadian Centre for Climate Modelling and Analysis (CCCma), Institute of Ocean Sciences [Sidney] (IOS), Fisheries and Oceans Canada (DFO), Department of Mathematics [Isfahan], University of Isfahan, Department of Physics and Astronomy [Calgary], University of Calgary, Scripps Institution of Oceanography (SIO), University of California [San Diego] (UC San Diego), University of California-University of California, Lawrence Berkeley National Laboratory [Berkeley] (LBNL), and National Research Council of Canada (NRC)
- Subjects
[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph] ,[SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology - Abstract
International audience; Motivated by the need to predict how the Arctic atmosphere will change in a warming world, this article summarizes recent advances made by the research consortium NETCARE (Network on Climate and Aerosols: Addressing Key Uncertainties in Remote Canadian Environments) that contribute to our fundamental understanding of Arctic aerosol particles as they relate to climate forcing. The overall goal of NETCARE research has been to use an interdisciplinary approach encompassing extensive field observations and a range of chemical transport, earth system, and biogeochemical models. Several major findings and advances have emerged from NETCARE since its formation in 2013 . (1) Unexpectedly high summertime dimethyl sulfide (DMS) levels were identified in ocean water and the overlying atmosphere in the Canadian Arctic Archipelago (CAA). Furthermore, melt ponds, which are widely prevalent, were identified as an important DMS source. (2) Evidence was found of widespread particle nucleation and growth in the marine boundary layer in the CAA in the summertime. DMS-oxidation-driven nucleation is facilitated by the presence of atmospheric ammonia arising from sea bird colony emissions, and potentially also from coastal regions, tundra, and biomass burning. Via accumulation of secondary organic material (SOA), a significant fraction of the new particles grow to sizes that are active in cloud droplet formation. Although the gaseous precursors to Arctic marine SOA remain poorly defined, the measured levels of common continental SOA precursors (isoprene and monoterpenes) were low, whereas elevated mixing ratios of oxygenated volatile organic compounds were inferred to arise via processes involving the sea surface microlayer. (3) The variability in the vertical distribution of black carbon (BC) under both springtime Arctic haze and more pristine summertime aerosol conditions was observed. Measured particle size distributions and mixing states were used to constrain, for the first time, calculations of aerosol–climate interactions under Arctic conditions. Aircraft- and ground-based measurements were used to better establish the BC source regions that supply the Arctic via long-range transport mechanisms. (4) Measurements of ice nucleating particles (INPs) in the Arctic indicate that a major source of these particles is mineral dust, likely derived from local sources in the summer and long-range transport in the spring. In addition, INPs are abundant in the sea surface microlayer in the Arctic, and possibly play a role in ice nucleation in the atmosphere when mineral dust concentrations are low. (5) Amongst multiple aerosol components, BC was observed to have the smallest effective deposition velocities to high Arctic snow.
- Published
- 2018
44. Diurnal variability, photochemical production and loss processes of hydrogen peroxide in the boundary layer over Europe
- Author
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Fischer, Horst, primary, Axinte, Raoul, additional, Bozem, Heiko, additional, Crowley, John N., additional, Ernest, Cheryl, additional, Gilge, Stefan, additional, Hafermann, Sascha, additional, Harder, Hartwig, additional, Hens, Korbinian, additional, Janssen, Ruud H. H., additional, Königstedt, Rainer, additional, Kubistin, Dagmar, additional, Mallik, Chinmay, additional, Martinez, Monica, additional, Novelli, Anna, additional, Parchatka, Uwe, additional, Plass-Dülmer, Christian, additional, Pozzer, Andrea, additional, Regelin, Eric, additional, Reiffs, Andreas, additional, Schmidt, Torsten, additional, Schuladen, Jan, additional, and Lelieveld, Jos, additional
- Published
- 2019
- Full Text
- View/download PDF
45. Vertical profiles of light absorption and scattering associated with black-carbon particle fractions in the springtime Arctic above 79° N
- Author
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Leaitch, W. Richard, primary, Kodros, John K., additional, Willis, Megan D., additional, Hanna, Sarah, additional, Schulz, Hannes, additional, Andrews, Elisabeth, additional, Bozem, Heiko, additional, Burkart, Julia, additional, Hoor, Peter, additional, Kolonjari, Felicia, additional, Ogren, John A., additional, Sharma, Sangeeta, additional, Si, Meng, additional, von Salzen, Knut, additional, Bertram, Allan K., additional, Herber, Andreas, additional, Abbatt, Jonathan P. D., additional, and Pierce, Jeffrey R., additional
- Published
- 2019
- Full Text
- View/download PDF
46. Response to Reviewer 2
- Author
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Bozem, Heiko, primary
- Published
- 2019
- Full Text
- View/download PDF
47. Response to Reviewer 1
- Author
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Bozem, Heiko, primary
- Published
- 2019
- Full Text
- View/download PDF
48. High Arctic aircraft measurements characterising black carbon vertical variability in spring and summer
- Author
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Schulz, Hannes, primary, Zanatta, Marco, additional, Bozem, Heiko, additional, Leaitch, W. Richard, additional, Herber, Andreas B., additional, Burkart, Julia, additional, Willis, Megan D., additional, Kunkel, Daniel, additional, Hoor, Peter M., additional, Abbatt, Jonathan P. D., additional, and Gerdes, Rüdiger, additional
- Published
- 2019
- Full Text
- View/download PDF
49. Aircraft-based measurements of High Arctic springtime aerosol show evidence for vertically varying sources, transport and composition
- Author
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Willis, Megan D., primary, Bozem, Heiko, additional, Kunkel, Daniel, additional, Lee, Alex K. Y., additional, Schulz, Hannes, additional, Burkart, Julia, additional, Aliabadi, Amir A., additional, Herber, Andreas B., additional, Leaitch, W. Richard, additional, and Abbatt, Jonathan P. D., additional
- Published
- 2019
- Full Text
- View/download PDF
50. Meteorological conditions during the ACLOUD/PASCAL field campaign near Svalbard in early summer 2017
- Author
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Knudsen, Erlend M., primary, Heinold, Bernd, additional, Dahlke, Sandro, additional, Bozem, Heiko, additional, Crewell, Susanne, additional, Gorodetskaya, Irina V., additional, Heygster, Georg, additional, Kunkel, Daniel, additional, Maturilli, Marion, additional, Mech, Mario, additional, Viceto, Carolina, additional, Rinke, Annette, additional, Schmithüsen, Holger, additional, Ehrlich, André, additional, Macke, Andreas, additional, Lüpkes, Christof, additional, and Wendisch, Manfred, additional
- Published
- 2018
- Full Text
- View/download PDF
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