Articles | Volume 22, issue 11
https://doi.org/10.5194/acp-22-7193-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-22-7193-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
03 Jun 2022
Research article |
| 03 Jun 2022
| 03 Jun 2022
Contribution of Asian emissions to upper tropospheric CO over the remote Pacific
Linda Smoydzin
CORRESPONDING AUTHOR
Institute for Atmospheric Physics, Johannes Gutenberg University, Mainz, Germany
Peter Hoor
Institute for Atmospheric Physics, Johannes Gutenberg University, Mainz, Germany
Related authors
Linda Smoydzin, Vera Bense, Heiko Bozem, Philipp Joppe, Daniel Kunkel, Hans-Christoph Lachnitt, Holger Tost, Andreas Zahn, Helmut Ziereis, Martin Riese, and Peter Hoor
EGUsphere, https://doi.org/10.5194/egusphere-2025-5372, https://doi.org/10.5194/egusphere-2025-5372, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
During a research flight in early October elevated upper tropospheric mixing ratios of CO, NO, NOy and O3 were observed over a distance of more than 1000 km east of the Brasilian coast. Ozone mixing ratios are 20–40 ppbv higher than during a flight in early September. By combining aircraft observations with model simulations we find that ozone production from biomass burning over Amazonia caused predominantly the ozone enhancements which have a local effect on the radiative forcing of 50 mWm−2.
Madhuri Umbarkar, Daniel Kunkel, Annette Miltenberger, Hans-Christoph Lachnitt, Thorsten Kaluza, Cornelis Schwenk, and Peter Hoor
EGUsphere, https://doi.org/10.5194/egusphere-2025-5142, https://doi.org/10.5194/egusphere-2025-5142, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
We present an extratropical cyclone case study over the North Atlantic, focusing on the role of atmospheric gravity waves (GWs) in the generation of enhanced vertical wind shear and (clear-air) turbulence, as well as their impact on tracers distribution in the lowermost stratosphere. Our research suggests the GW related processes should be considered as a key for UTLS transport and mixing and as an important candidate for the interpretation of CAT, that appear to emanate from GW-induced shear.
Linda Smoydzin, Vera Bense, Heiko Bozem, Philipp Joppe, Daniel Kunkel, Hans-Christoph Lachnitt, Holger Tost, Andreas Zahn, Helmut Ziereis, Martin Riese, and Peter Hoor
EGUsphere, https://doi.org/10.5194/egusphere-2025-5372, https://doi.org/10.5194/egusphere-2025-5372, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
During a research flight in early October elevated upper tropospheric mixing ratios of CO, NO, NOy and O3 were observed over a distance of more than 1000 km east of the Brasilian coast. Ozone mixing ratios are 20–40 ppbv higher than during a flight in early September. By combining aircraft observations with model simulations we find that ozone production from biomass burning over Amazonia caused predominantly the ozone enhancements which have a local effect on the radiative forcing of 50 mWm−2.
Paul Konopka, Felix Ploeger, Francesco D'Amato, Teresa Campos, Marc von Hobe, Shawn B. Honomichl, Peter Hoor, Laura L. Pan, Michelle L. Santee, Silvia Viciani, Kaley A. Walker, and Michaela I. Hegglin
Atmos. Chem. Phys., 25, 17973–17996, https://doi.org/10.5194/acp-25-17973-2025, https://doi.org/10.5194/acp-25-17973-2025, 2025
Short summary
Short summary
We present an improved version of the Chemical Lagrangian Model of the Stratosphere (CLaMS-3.0), which better represents transport from the lower atmosphere to the upper troposphere and lower stratosphere. By refining grid resolution and improving convection representation, the model more accurately simulates carbon monoxide transport. Comparisons with satellite and in situ observations highlight its ability to capture seasonal variations and improve our understanding of atmospheric transport.
Patrick Konjari, Christian Rolf, Martina Krämer, Armin Afchine, Nicole Spelten, Irene Bartolome Garcia, Annette Miltenberger, Nicolas Emig, Philipp Joppe, Johannes Schneider, Yun Li, Andreas Petzold, Heiko Bozem, and Peter Hoor
Atmos. Chem. Phys., 25, 18031–18050, https://doi.org/10.5194/acp-25-18031-2025, https://doi.org/10.5194/acp-25-18031-2025, 2025
Short summary
Short summary
We investigated how a powerful storm over southern Sweden in June 2024 transported ice particles and moist air into the normally dry stratosphere. We observed unusually high water vapor and ice levels up to 1.5 kilometers above the tropopause. Although the extra water vapor lasted only a few days to weeks, it shows how such storms can temporarily alter the upper atmosphere’s composition.
Bärbel Vogel, Valentin Lauther, Franziska Köllner, Fatih Ekinci, Christian Rolf, Johannes Strobel, Ronja van Luijt, Michael C. Volk, Stephan Borrmann, Antonis Dragoneas, Oliver Eppers, Sergej Molleker, Peter Hoor, Linda Ort, Franziska Weyland, Andreas Zahn, Jan Clemens, Gebhard Günther, Oleh Kachula, Rolf Müller, Felix Ploeger, and Martin Riese
EGUsphere, https://doi.org/10.5194/egusphere-2025-5609, https://doi.org/10.5194/egusphere-2025-5609, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
This work highlights the impact of the Asian summer monsoon on the chemical composition of the upper troposphere and lower stratosphere. Measurements of trace gases and aerosol particles uplifted by the Asian summer monsoon to higher altitudes are sparse. Here, we had the opportunity to use a whole suite of different measured trace gases and the chemical composition of aerosols, in combination with simulations, to better understand the complex transport and mixing processes in this region.
Anna Breuninger, Philipp Joppe, Jonas Wilsch, Cornelis Schwenk, Heiko Bozem, Nicolas Emig, Laurin Merkel, Rainer Rossberg, Timo Keber, Arthur Kutschka, Philipp Waleska, Stefan Hofmann, Sarah Richter, Florian Ungeheuer, Konstantin Dörholt, Thorsten Hoffmann, Annette Miltenberger, Johannes Schneider, Peter Hoor, and Alexander L. Vogel
Atmos. Chem. Phys., 25, 16533–16551, https://doi.org/10.5194/acp-25-16533-2025, https://doi.org/10.5194/acp-25-16533-2025, 2025
Short summary
Short summary
This study investigates molecular organic aerosol composition in the upper troposphere and lower stratosphere from an airborne campaign over Central Europe in summer 2024. Via ultra-high-performance liquid chromatography and high-resolution mass spectrometry of tropospheric and stratospheric filter samples, we identified various organic compounds. Our findings underscore the significant cross-tropopause transport of biogenic secondary organic aerosol and anthropogenic pollutants.
Heiko Bozem, Philipp Joppe, Yun Li, Nicolas Emig, Armin Afchine, Anna Breuninger, Joachim Curtius, Stefan Hofmann, Sadath Ismayil, Konrad Kandler, Daniel Kunkel, Arthur Kutschka, Hans-Christoph Lachnitt, Andreas Petzold, Sarah Richter, Timo Röschenthaler, Christian Rolf, Lisa Schneider, Johannes Schneider, Alexander Vogel, and Peter Hoor
Atmos. Meas. Tech., 18, 6545–6568, https://doi.org/10.5194/amt-18-6545-2025, https://doi.org/10.5194/amt-18-6545-2025, 2025
Short summary
Short summary
Deployed on a Learjet as a tandem measurement platform during the TPEx I (TropoPause composition gradients and mixing Experiment) campaign in June 2024, the new TPC-TOSS (TropoPause Composition Towed Sensor Shuttle) system delivers high-resolution in situ data on ozone, aerosol, and key meteorological parameters. Laboratory and in-flight tests confirmed its precision and stability. Observed gradients near the tropopause reveal active mixing and transport processes in the tropopause region.
Chun Hang Chau, Peter Hoor, Katharina Kaiser, and Holger Tost
EGUsphere, https://doi.org/10.5194/egusphere-2025-5382, https://doi.org/10.5194/egusphere-2025-5382, 2025
Short summary
Short summary
This study examines the sensitivity of different greenhouse gases to vertical mixing by clear air turbulence in the upper troposphere and lower stratosphere. We found that ozone is most sensitive to vertical mixing and could lead to cooling at the top of the atmosphere by -0.2 W/m2. We also found that the vertical mixing by clear air turbulence could lead to changes in methane lifetime and the ozone chemistry.
Philipp Joppe, Johannes Schneider, Jonas Wilsch, Heiko Bozem, Anna Breuninger, Joachim Curtius, Martin Ebert, Nicolas Emig, Peter Hoor, Sadath Ismayil, Konrad Kandler, Daniel Kunkel, Isabel Kurth, Hans-Christoph Lachnitt, Yun Li, Annette Miltenberger, Sarah Richter, Christian Rolf, Lisa Schneider, Cornelis Schwenk, Nicole Spelten, Alexander L. Vogel, Yafang Cheng, and Stephan Borrmann
Atmos. Chem. Phys., 25, 15077–15103, https://doi.org/10.5194/acp-25-15077-2025, https://doi.org/10.5194/acp-25-15077-2025, 2025
Short summary
Short summary
We show measurements of a filament with biomass burning influence transported by a warm conveyor belt (WCB) into the tropopause region over Europe. The pollution originates from Canadian forest fires and is transported in the lower troposphere towards Europe. The WCB transport is followed by mixing with air masses of stratospheric chemical signatures. We hypothesize that this mixing leads to a change in the vertical gradient of the potential temperature.
Linda Ort, Andrea Pozzer, Peter Hoor, Florian Obersteiner, Andreas Zahn, Thomas B. Ryerson, Chelsea R. Thompson, Jeff Peischl, Róisín Commane, Bruce Daube, Ilann Bourgeois, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 25, 14987–15007, https://doi.org/10.5194/acp-25-14987-2025, https://doi.org/10.5194/acp-25-14987-2025, 2025
Short summary
Short summary
This study investigates the role of lightning emissions on the O3–CO ratio in the northern subtropics. We used in situ observations and a global circulation model to show an effect of up to 40 % onto the subtropical O3–CO ratio by tropical air masses transported via the Hadley cell. This influence of lightning emissions and its photochemistry has a global effect on trace and greenhouse gases and needs to be considered for global chemical distributions.
Sophie Bauchinger, Andreas Engel, Markus Jesswein, Timo Keber, Harald Bönisch, Florian Obersteiner, Andreas Zahn, Nicolas Emig, Peter Hoor, Hans-Christoph Lachnitt, Franziska Weyland, Linda Ort, and Tanja J. Schuck
Atmos. Chem. Phys., 25, 14167–14186, https://doi.org/10.5194/acp-25-14167-2025, https://doi.org/10.5194/acp-25-14167-2025, 2025
Short summary
Short summary
We compared different ways to define the upper barrier of the troposphere in the extra-tropics, the “tropopause”. By analysing ozone distributions sorted by different definitions, we found that the traditional temperature-based tropopause works less well than dynamic or tracer-based definitions. We saw a sharper transition of ozone across the tropopause using a higher value of potential vorticity than often used and recommend this value for future studies of exchange processes in this region.
Chun Hang Chau, Peter Hoor, and Holger Tost
Atmos. Chem. Phys., 25, 13123–13140, https://doi.org/10.5194/acp-25-13123-2025, https://doi.org/10.5194/acp-25-13123-2025, 2025
Short summary
Short summary
This study examines how the turbulence in the upper troposphere/lower stratosphere (UTLS) could modify the tracer distribution under different situations. Using a multi-scale chemistry model with a novel diagnostic, we found that both the pre-existing tracer gradient and the dynamical and thermodynamical forcing play a role in modifying the tracer distribution. These results allow further research on the UTLS turbulent mixing and its implications for the climate system.
Nicolas Emig, Annette K. Miltenberger, Peter M. Hoor, and Andreas Petzold
Atmos. Chem. Phys., 25, 13077–13101, https://doi.org/10.5194/acp-25-13077-2025, https://doi.org/10.5194/acp-25-13077-2025, 2025
Short summary
Short summary
This study presents in situ observations of cirrus occurrence from aircraft measurements in the extratropical transition layer (ExTL) using simultaneous measurements from two platforms. Lagrangian diagnostics based on high-resolution ICON simulations show long residence times of the cirrus in stratospheric air, allowing us to separate different diabatic processes during transit. The findings suggest that radiative diabatic cloud processes significantly impact the tropopause thermodynamic structure.
Johannes Schneider, Christiane Schulz, Florian Rubach, Anna Ludwig, Jonas Wilsch, Philipp Joppe, Christian Gurk, Sergej Molleker, Laurent Poulain, Florian Obersteiner, Torsten Gehrlein, Harald Bönisch, Andreas Zahn, Peter Hoor, Nicolas Emig, Heiko Bozem, Stephan Borrmann, and Markus Hermann
Atmos. Meas. Tech., 18, 5103–5128, https://doi.org/10.5194/amt-18-5103-2025, https://doi.org/10.5194/amt-18-5103-2025, 2025
Short summary
Short summary
An instrumented container laboratory is operated on regular commercial passenger flights to obtain a long-term representative dataset on the composition of the upper troposphere and lower stratosphere. Here we report on the development of a fully automated aerosol mass spectrometer for this project. We present technical specifications, necessary modifications for the automation, instrument calibration and comparisons, detection limits, and the first in-flight data.
Rodrigo J. Seguel, Charlie Opazo, Yann Cohen, Owen R. Cooper, Laura Gallardo, Björn-Martin Sinnhuber, Florian Obersteiner, Andreas Zahn, Peter Hoor, Susanne Rohs, and Andreas Marsing
Atmos. Chem. Phys., 25, 8553–8573, https://doi.org/10.5194/acp-25-8553-2025, https://doi.org/10.5194/acp-25-8553-2025, 2025
Short summary
Short summary
We explored ozone differences between the Northern Hemisphere and Southern Hemispheres in the upper troposphere–lower stratosphere. We found lower ozone (with stratospheric origin) in the Southern Hemisphere, especially during years of severe ozone depletion. Sudden stratospheric warming events increased the ozone in each hemisphere, highlighting the relationship between stratospheric processes and ozone in the upper troposphere, where ozone is an important greenhouse gas.
Markus Jesswein, Valentin Lauther, Nicolas Emig, Peter Hoor, Timo Keber, Hans-Christoph Lachnitt, Linda Ort, Tanja Schuck, Johannes Strobel, Ronja Van Luijt, C. Michael Volk, Franziska Weyland, and Andreas Engel
Atmos. Chem. Phys., 25, 8107–8126, https://doi.org/10.5194/acp-25-8107-2025, https://doi.org/10.5194/acp-25-8107-2025, 2025
Short summary
Short summary
The study investigates transport within the Asian Summer Monsoon, focusing on how CH2Cl2 reaches the subarctic tropopause region. Using data from the PHILEAS campaign in 2023, events with increased mixing ratios were detected. Their origin, the transport paths to the tropopause region, and the potential entry into the stratosphere were analyzed. The East Asian Summer Monsoon was identified as the main transport pathway, with only a small contribution to the stratosphere in the following days.
Franziska Weyland, Peter Hoor, Daniel Kunkel, Thomas Birner, Felix Plöger, and Katharina Turhal
Atmos. Chem. Phys., 25, 1227–1252, https://doi.org/10.5194/acp-25-1227-2025, https://doi.org/10.5194/acp-25-1227-2025, 2025
Short summary
Short summary
The lowermost stratosphere (LMS) plays an important role in the Earth's climate, containing strong gradients of ozone and water vapor. Our results indicate that the thermodynamic structure of the LMS was changing between 1979–2019 in response to anthropogenic climate change and the recovery of stratospheric ozone, also indicating large-scale circulation changes. We find that both the upper and the lower LMS boundaries show an (upward) trend, which has implications for the LMS mass.
Katharina Turhal, Felix Plöger, Jan Clemens, Thomas Birner, Franziska Weyland, Paul Konopka, and Peter Hoor
Atmos. Chem. Phys., 24, 13653–13679, https://doi.org/10.5194/acp-24-13653-2024, https://doi.org/10.5194/acp-24-13653-2024, 2024
Short summary
Short summary
The tropopause separates the troposphere, where many greenhouse gases originate, from the stratosphere. This study examines a tropopause defined by potential vorticity – an analogue for angular momentum that changes sharply in the subtropics, creating a transport barrier. Between 1980 and 2017, this tropopause shifted poleward at lower altitudes and equatorward above, suggesting height-dependent changes in atmospheric circulation that may affect greenhouse gas distribution and global warming.
Luis F. Millán, Peter Hoor, Michaela I. Hegglin, Gloria L. Manney, Harald Boenisch, Paul Jeffery, Daniel Kunkel, Irina Petropavlovskikh, Hao Ye, Thierry Leblanc, and Kaley Walker
Atmos. Chem. Phys., 24, 7927–7959, https://doi.org/10.5194/acp-24-7927-2024, https://doi.org/10.5194/acp-24-7927-2024, 2024
Short summary
Short summary
In the Observed Composition Trends And Variability in the UTLS (OCTAV-UTLS) Stratosphere-troposphere Processes And their Role in Climate (SPARC) activity, we have mapped multiplatform ozone datasets into coordinate systems to systematically evaluate the influence of these coordinates on binned climatological variability. This effort unifies the work of studies that focused on individual coordinate system variability. Our goal was to create the most comprehensive assessment of this topic.
Niklas Karbach, Lisa Höhler, Peter Hoor, Heiko Bozem, Nicole Bobrowski, and Thorsten Hoffmann
Atmos. Meas. Tech., 17, 4081–4086, https://doi.org/10.5194/amt-17-4081-2024, https://doi.org/10.5194/amt-17-4081-2024, 2024
Short summary
Short summary
The system presented here can accurately generate and reproduce a stable flow of gas mixtures of known concentrations over several days using ambient air as a dilution medium. In combination with the small size and low weight of the system, this enables the calibration of hydrogen sensors in the field, reducing the influence of matrix effects on the accuracy of the sensor. The system is inexpensive to assemble and easy to maintain, which is the key to reliable measurement results.
Philipp Joppe, Johannes Schneider, Katharina Kaiser, Horst Fischer, Peter Hoor, Daniel Kunkel, Hans-Christoph Lachnitt, Andreas Marsing, Lenard Röder, Hans Schlager, Laura Tomsche, Christiane Voigt, Andreas Zahn, and Stephan Borrmann
Atmos. Chem. Phys., 24, 7499–7522, https://doi.org/10.5194/acp-24-7499-2024, https://doi.org/10.5194/acp-24-7499-2024, 2024
Short summary
Short summary
From aircraft measurements in the upper troposphere/lower stratosphere, we find a correlation between the ozone and particulate sulfate in the lower stratosphere. The correlation exhibits some variability over the measurement period exceeding the background sulfate-to-ozone correlation. From our analysis, we conclude that gas-to-particle conversion of volcanic sulfur dioxide leads to observed enhanced sulfate aerosol mixing ratios.
Tanja J. Schuck, Johannes Degen, Eric Hintsa, Peter Hoor, Markus Jesswein, Timo Keber, Daniel Kunkel, Fred Moore, Florian Obersteiner, Matt Rigby, Thomas Wagenhäuser, Luke M. Western, Andreas Zahn, and Andreas Engel
Atmos. Chem. Phys., 24, 689–705, https://doi.org/10.5194/acp-24-689-2024, https://doi.org/10.5194/acp-24-689-2024, 2024
Short summary
Short summary
We study the interhemispheric gradient of sulfur hexafluoride (SF6), a strong long-lived greenhouse gas. Its emissions are stronger in the Northern Hemisphere; therefore, mixing ratios in the Southern Hemisphere lag behind. Comparing the observations to a box model, the model predicts air in the Southern Hemisphere to be older. For a better agreement, the emissions used as model input need to be increased (and their spatial pattern changed), and we need to modify north–south transport.
Frederik Harzer, Hella Garny, Felix Ploeger, Harald Bönisch, Peter Hoor, and Thomas Birner
Atmos. Chem. Phys., 23, 10661–10675, https://doi.org/10.5194/acp-23-10661-2023, https://doi.org/10.5194/acp-23-10661-2023, 2023
Short summary
Short summary
We study the statistical relation between year-by-year fluctuations in winter-mean ozone and the strength of the stratospheric polar vortex. In the latitude–pressure plane, regression analysis shows that anomalously weak polar vortex years are associated with three pronounced local ozone maxima over the polar cap relative to the winter climatology. These response maxima primarily reflect the non-trivial combination of different ozone transport processes with varying relative contributions.
Luis F. Millán, Gloria L. Manney, Harald Boenisch, Michaela I. Hegglin, Peter Hoor, Daniel Kunkel, Thierry Leblanc, Irina Petropavlovskikh, Kaley Walker, Krzysztof Wargan, and Andreas Zahn
Atmos. Meas. Tech., 16, 2957–2988, https://doi.org/10.5194/amt-16-2957-2023, https://doi.org/10.5194/amt-16-2957-2023, 2023
Short summary
Short summary
The determination of atmospheric composition trends in the upper troposphere and lower stratosphere (UTLS) is still highly uncertain. We present the creation of dynamical diagnostics to map several ozone datasets (ozonesondes, lidars, aircraft, and satellite measurements) in geophysically based coordinate systems. The diagnostics can also be used to analyze other greenhouse gases relevant to surface climate and UTLS chemistry.
Hans-Christoph Lachnitt, Peter Hoor, Daniel Kunkel, Martina Bramberger, Andreas Dörnbrack, Stefan Müller, Philipp Reutter, Andreas Giez, Thorsten Kaluza, and Markus Rapp
Atmos. Chem. Phys., 23, 355–373, https://doi.org/10.5194/acp-23-355-2023, https://doi.org/10.5194/acp-23-355-2023, 2023
Short summary
Short summary
We present an analysis of high-resolution airborne measurements during a flight of the DEEPWAVE 2014 campaign in New Zealand. The focus of this flight was to study the effects of enhanced mountain wave activity over the Southern Alps. We discuss changes in the upstream and downstream distributions of N2O and CO and show that these changes are related to turbulence-induced trace gas fluxes which have persistent effects on the trace gas composition in the lower stratosphere.
Paul Konopka, Mengchu Tao, Marc von Hobe, Lars Hoffmann, Corinna Kloss, Fabrizio Ravegnani, C. Michael Volk, Valentin Lauther, Andreas Zahn, Peter Hoor, and Felix Ploeger
Geosci. Model Dev., 15, 7471–7487, https://doi.org/10.5194/gmd-15-7471-2022, https://doi.org/10.5194/gmd-15-7471-2022, 2022
Short summary
Short summary
Pure trajectory-based transport models driven by meteorology derived from reanalysis products (ERA5) take into account only the resolved, advective part of transport. That means neither mixing processes nor unresolved subgrid-scale advective processes like convection are included. The Chemical Lagrangian Model of the Stratosphere (CLaMS) includes these processes. We show that isentropic mixing dominates unresolved transport. The second most important transport process is unresolved convection.
Helmut Ziereis, Peter Hoor, Jens-Uwe Grooß, Andreas Zahn, Greta Stratmann, Paul Stock, Michael Lichtenstern, Jens Krause, Vera Bense, Armin Afchine, Christian Rolf, Wolfgang Woiwode, Marleen Braun, Jörn Ungermann, Andreas Marsing, Christiane Voigt, Andreas Engel, Björn-Martin Sinnhuber, and Hermann Oelhaf
Atmos. Chem. Phys., 22, 3631–3654, https://doi.org/10.5194/acp-22-3631-2022, https://doi.org/10.5194/acp-22-3631-2022, 2022
Short summary
Short summary
Airborne observations were conducted in the lowermost Arctic stratosphere during the winter of 2015/2016. The observed distribution of reactive nitrogen shows clear indications of nitrification in mid-winter and denitrification in late winter. This was caused by the formation of polar stratospheric cloud particles, which were observed during several flights. The sedimentation and evaporation of these particles and the descent of air masses cause a redistribution of reactive nitrogen.
Valentin Lauther, Bärbel Vogel, Johannes Wintel, Andrea Rau, Peter Hoor, Vera Bense, Rolf Müller, and C. Michael Volk
Atmos. Chem. Phys., 22, 2049–2077, https://doi.org/10.5194/acp-22-2049-2022, https://doi.org/10.5194/acp-22-2049-2022, 2022
Short summary
Short summary
We show airborne in situ measurements of the very short-lived ozone-depleting substances CH2Cl2 and CHCl3, revealing particularly high concentrations of both species in the lower stratosphere. Back-trajectory calculations and 3D model simulations show that the air masses with high concentrations originated in the Asian boundary layer and were transported via the Asian summer monsoon. We also identify a fast transport pathway into the stratosphere via the North American monsoon and by hurricanes.
Markus Jesswein, Heiko Bozem, Hans-Christoph Lachnitt, Peter Hoor, Thomas Wagenhäuser, Timo Keber, Tanja Schuck, and Andreas Engel
Atmos. Chem. Phys., 21, 17225–17241, https://doi.org/10.5194/acp-21-17225-2021, https://doi.org/10.5194/acp-21-17225-2021, 2021
Short summary
Short summary
This study presents and compares inorganic chlorine (Cly) derived from observations with the HALO research aircraft in the Antarctic late winter–early fall 2019 and the Arctic winter 2015–2016. Trend-corrected correlations from the Northern Hemisphere show excellent agreement with those from the Southern Hemisphere. After observation allocation inside and outside the vortex based on N2O measurements, results of the two campaigns reveal substantial differences in Cly within the respective vortex.
Meike K. Rotermund, Vera Bense, Martyn P. Chipperfield, Andreas Engel, Jens-Uwe Grooß, Peter Hoor, Tilman Hüneke, Timo Keber, Flora Kluge, Benjamin Schreiner, Tanja Schuck, Bärbel Vogel, Andreas Zahn, and Klaus Pfeilsticker
Atmos. Chem. Phys., 21, 15375–15407, https://doi.org/10.5194/acp-21-15375-2021, https://doi.org/10.5194/acp-21-15375-2021, 2021
Short summary
Short summary
Airborne total bromine (Brtot) and tracer measurements suggest Brtot-rich air masses persistently protruded into the lower stratosphere (LS), creating a high Brtot region over the North Atlantic in fall 2017. The main source is via isentropic transport by the Asian monsoon and to a lesser extent transport across the extratropical tropopause as quantified by a Lagrange model. The transport of Brtot via Central American hurricanes is also observed. Lastly, the impact of Brtot on LS O3 is assessed.
Thorsten Kaluza, Daniel Kunkel, and Peter Hoor
Weather Clim. Dynam., 2, 631–651, https://doi.org/10.5194/wcd-2-631-2021, https://doi.org/10.5194/wcd-2-631-2021, 2021
Short summary
Short summary
We present a 10-year analysis on the occurrence of strong wind shear in the Northern Hemisphere, focusing on the region around the transport barrier that separates the first two layers of the atmosphere. The major result of our analysis is that strong wind shear above a certain threshold occurs frequently and nearly exclusively in this region, which, as an indicator for turbulent mixing, might have major implications concerning the separation efficiency of the transport barrier.
Franziska Köllner, Johannes Schneider, Megan D. Willis, Hannes Schulz, Daniel Kunkel, Heiko Bozem, Peter Hoor, Thomas Klimach, Frank Helleis, Julia Burkart, W. Richard Leaitch, Amir A. Aliabadi, Jonathan P. D. Abbatt, Andreas B. Herber, and Stephan Borrmann
Atmos. Chem. Phys., 21, 6509–6539, https://doi.org/10.5194/acp-21-6509-2021, https://doi.org/10.5194/acp-21-6509-2021, 2021
Short summary
Short summary
We present in situ observations of vertically resolved particle chemical composition in the summertime Arctic lower troposphere. Our analysis demonstrates the strong vertical contrast between particle properties within the boundary layer and aloft. Emissions from vegetation fires and anthropogenic sources in northern Canada, Europe, and East Asia influenced particle composition in the free troposphere. Organics detected in Arctic aerosol particles can partly be identified as dicarboxylic acids.
Johannes Schneider, Ralf Weigel, Thomas Klimach, Antonis Dragoneas, Oliver Appel, Andreas Hünig, Sergej Molleker, Franziska Köllner, Hans-Christian Clemen, Oliver Eppers, Peter Hoppe, Peter Hoor, Christoph Mahnke, Martina Krämer, Christian Rolf, Jens-Uwe Grooß, Andreas Zahn, Florian Obersteiner, Fabrizio Ravegnani, Alexey Ulanovsky, Hans Schlager, Monika Scheibe, Glenn S. Diskin, Joshua P. DiGangi, John B. Nowak, Martin Zöger, and Stephan Borrmann
Atmos. Chem. Phys., 21, 989–1013, https://doi.org/10.5194/acp-21-989-2021, https://doi.org/10.5194/acp-21-989-2021, 2021
Short summary
Short summary
During five aircraft missions, we detected aerosol particles containing meteoric material in the lower stratosphere. The stratospheric measurements span a latitude range from 15 to 68° N, and we find that at potential temperature levels of more than 40 K above the tropopause; particles containing meteoric material occur at similar abundance fractions across latitudes and seasons. We conclude that meteoric material is efficiently distributed between high and low latitudes by isentropic mixing.
Cited articles
Bey, I., Jacob, D. J., Logan, J. A., and Yantosca, R. M.: Asian chemical
outflow to the Pacific in spring: Origins, pathways, and budgets, J. Geophys. Res.-Atmos., 106, 23097–23113,
https://doi.org/10.1029/2001JD000806, 2001. a
Breeden, M. L., Butler, A. H., Albers, J. R., Sprenger, M., and Langford, A. O.: The spring transition of the North Pacific jet and its relation to deep stratosphere-to-troposphere mass transport over western North America, Atmos. Chem. Phys., 21, 2781–2794, https://doi.org/10.5194/acp-21-2781-2021, 2021. a, b
Chen, Y., Zhao, C., Qiang, Z., Deng, Z., Huang, M., and Ma, X.: Aircraft study
of Mountain Chimney Effect of Beijing, China, J. Geophys. Res., 114, 1–10, https://doi.org/10.1029/2008JD010610, 2009. a
Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli, P., Kobayashi,
S., Andrae, U., Balmaseda, M. A., Balsamo, G., Bauer, P., Bechtold, P.,
Beljaars, A. C. M., van de Berg, L., Bidlot, J., Bormann, N., Delsol, C.,
Dragani, R., Fuentes, M., Geer, A. J., Haimberger, L., Healy, S. B.,
Hersbach, H., Hólm, E. V., Isaksen, L., Kållberg, P., Köhler, M.,
Matricardi, M., McNally, A. P., Monge-Sanz, B. M., Morcrette, J.-J., Park,
B.-K., Peubey, C., de Rosnay, P., Tavolato, C., Thépaut, J.-N., and Vitart,
F.: The ERA-Interim reanalysis: configuration and performance of the data
assimilation system, Q. J. Roy. Meteor. Soc.,
137, 553–597, https://doi.org/10.1002/qj.828, 2011. a
Deeter, M., Edwards, D., Gille, J., and Worden, H.: Information content of
MOPITT CO profile retrievals: Temporal and geographical variability, J. Geophys. Res.-Atmos., 120, 12723–12738,
https://doi.org/10.1002/2015JD024024, 2015. a
Deeter, M. N., Edwards, D. P., Francis, G. L., Gille, J. C., Mao, D., Martínez-Alonso, S., Worden, H. M., Ziskin, D., and Andreae, M. O.: Radiance-based retrieval bias mitigation for the MOPITT instrument: the version 8 product, Atmos. Meas. Tech., 12, 4561–4580, https://doi.org/10.5194/amt-12-4561-2019, 2019 (data available at: https://www2.acom.ucar.edu/mopitt, last access: June 2020). a, b, c
Dickerson, R., Li, C., Li, Z., Marufu, L., Stehr, J., McClure, B., Krotkov, N.,
Chen, H., Wang, P., Xia, X., Ban, X., and Gong, F.: Aircraft Observations of
Dust and Pollutants over NE China: Insight into the Meteorological Mechanisms
of Long-Range Transport, J. Geophys. Res., 112, D24S90,
https://doi.org/10.1029/2007JD008999, 2007. a
Ding, A., Wang, T., Xue, L., Gao, J., Stohl, A., Lei, H., Jin, D., Ren, Y.,
Wang, X., Wei, X., Qi, Y., Liu, J., and Zhang, X.: Transport of north China
air pollution by midlatitude cyclones: Case study of aircraft measurements in
summer 2007, J. Geophys. Res.-Atmos., 114, D08304,
https://doi.org/10.1029/2008JD011023, 2009. a
Ding, K., Liu, J., Ding, A., Liu, Q., Zhao, T. L., Shi, J., Han, Y., Wang, H., and Jiang, F.: Uplifting of carbon monoxide from biomass burning and anthropogenic sources to the free troposphere in East Asia, Atmos. Chem. Phys., 15, 2843–2866, https://doi.org/10.5194/acp-15-2843-2015, 2015. a
Di Pierro, M., Jaeglé, L., and Anderson, T. L.: Satellite observations of aerosol transport from East Asia to the Arctic: three case studies, Atmos. Chem. Phys., 11, 2225–2243, https://doi.org/10.5194/acp-11-2225-2011, 2011. a
Eckhardt, S., Stohl, A., Wernli, H., James, P., Forster, C., and Spichtinger,
N.: A 15-Year Climatology of Warm Conveyor Belts, J. Climate, 17,
218–237, 2004. a
Garny, H. and Randel, W. J.: Transport pathways from the Asian monsoon anticyclone to the stratosphere, Atmos. Chem. Phys., 16, 2703–2718, https://doi.org/10.5194/acp-16-2703-2016, 2016. a
Gehring, J., Oertel, A., Vignon, É., Jullien, N., Besic, N., and Berne, A.: Microphysics and dynamics of snowfall associated with a warm conveyor belt over Korea, Atmos. Chem. Phys., 20, 7373–7392, https://doi.org/10.5194/acp-20-7373-2020, 2020. a
Han, H., Liu, J., Yuan, H., Jiang, F., Zhu, Y., Wu, Y., Wang, T., and Zhuang,
B.: Impacts of Synoptic Weather Patterns and their Persistency on Free
Tropospheric Carbon Monoxide Concentrations and Outflow in Eastern China,
J. Geophys. Res.-Atmos., 123, 7024–7046,
https://doi.org/10.1029/2017JD028172, 2018. a
Hannan, J., Fuelberg, H., Crawford, J., Sachse, G., and Blake, D.: The Role of
Wave Cyclones in Transporting Boundary Layer Air to the Free Troposphere
During the Spring 2001 NASA / TRACE-P Experiment, J. Geophys. Res.-Atmos., 108, 8785, https://doi.org/10.1029/2002JD003105, 2003. a
Heald, C., Jacob, D., Fiore, A., Emmons, L., Gille, J., Deeter, M., Warner, J.,
Edwards, D., Crawford, J., Hamlin, A., Sachse, G., and Browell, E.: Asian
outflow and trans-Pacific transport of carbon monoxide and ozone pollution:
An integrated satellite, aircraft and model perspective, J. Geophys. Res., 108, 4804, https://doi.org/10.1029/2003JD003507, 2003. a, b, c
Hoffmann, L., Rößler, T., Griessbach, S., Heng, Y., and Stein, O.: Lagrangian
transport simulations of volcanic sulfur dioxide emissions: Impact of
meteorological data products, J. Geophys. Res.-Atmos.,
121, 4651–4673, https://doi.org/10.1002/2015JD023749, 2016. a
Holzer, M., Hall, T., and Stull, R.: Seasonality and weather-driven variability
of transpacific transport, J. Geophys. Res., 110, D23103,
https://doi.org/10.1029/2005JD006261, 2005. a, b, c
Hu, Z., Huang, J., Zhao, C., Ma, Y., Jin, Q., Qian, Y., Leung, L. R., Bi, J., and Ma, J.: Trans-Pacific transport and evolution of aerosols: spatiotemporal characteristics and source contributions, Atmos. Chem. Phys., 19, 12709–12730, https://doi.org/10.5194/acp-19-12709-2019, 2019. a
Kaneyasu, N., Takeuchi, K., Hayashi, M., Fujita, S.-i., Uno, I., and Sasaki,
H.: Outflow patterns of pollutants from East Asia to the North Pacific in the
winter monsoon, J. Geophys. Res., 105, 17361–17378,
https://doi.org/10.1029/2000JD900138, 2000. a
Kiley, C. and Fuelberg, H.: An examination of summertime cyclone transport
processes during Intercontinental Chemical Transport Experiment (INTEX-A), J.
Geophys. Res, 111, 24–6, https://doi.org/10.1029/2006JD007115, 2006. a, b
Klich, C. A. and Fuelberg, H. E.: The role of horizontal model resolution in assessing the transport of CO in a middle latitude cyclone using WRF-Chem, Atmos. Chem. Phys., 14, 609–627, https://doi.org/10.5194/acp-14-609-2014, 2014. a
Knippertz, P. and Wernli, H.: A Lagrangian Climatology of Tropical Moisture
Exports to the Northern Hemispheric Extratropics, J. Climate, 23,
987–1003, https://doi.org/10.1175/2009JCLI3333.1, 2010. a
Lamarque, J.-F., Bond, T. C., Eyring, V., Granier, C., Heil, A., Klimont, Z., Lee, D., Liousse, C., Mieville, A., Owen, B., Schultz, M. G., Shindell, D., Smith, S. J., Stehfest, E., Van Aardenne, J., Cooper, O. R., Kainuma, M., Mahowald, N., McConnell, J. R., Naik, V., Riahi, K., and van Vuuren, D. P.: Historical (1850–2000) gridded anthropogenic and biomass burning emissions of reactive gases and aerosols: methodology and application, Atmos. Chem. Phys., 10, 7017–7039, https://doi.org/10.5194/acp-10-7017-2010, 2010. a
Lawrence, M. G. and Salzmann, M.: On interpreting studies of tracer transport by deep cumulus convection and its effects on atmospheric chemistry, Atmos. Chem. Phys., 8, 6037–6050, https://doi.org/10.5194/acp-8-6037-2008, 2008. a, b
Lawrence, M. G. and Lelieveld, J.: Atmospheric pollutant outflow from southern Asia: a review, Atmos. Chem. Phys., 10, 11017–11096, https://doi.org/10.5194/acp-10-11017-2010, 2010. a
Lelieveld, J., Bourtsoukidis, E., Brühl, C., Fischer, H., Fuchs, H.,
Harder, H., Hofzumahaus, A., Holland, F., Marno, D., Neumaier, M., Pozzer,
A., Schlager, H., Williams, J., Zahn, A., and Ziereis, H.: The South Asian
monsoon–pollution pump and purifier, Science, 361, 270–273,
https://doi.org/10.1126/science.aar2501, 2018. a, b
Liang, Q., Jaeglé, L., Hudman, R., Turquety, S., Jacob, D., Avery, M.,
Browell, E., Sachse, G., Blake, D., Brune, W., Ren, X., Cohen, R., Dibb, J.,
Fried, A., Fuelberg, H., Porter, M., Heikes, B., Huey, G., Singh, H., and
Wennberg, P.: Summertime influence of Asian pollution in the free troposphere
over North America, J. Geophys. Res.-Atmos., 112,
D12S11, https://doi.org/10.1029/2006JD007919, 2007. a, b
Liu, J., Drummond, J., Jones, D., Cao, Z., Bremer, H., Kar, J., Zou, J.,
Florian, N., and Gille, J.: Large horizontal gradients in atmospheric CO at
the synoptic scale as seen by spaceborne Measurements of Pollution in the
Troposphere, J. Geophys. Res., 111, D02306,
https://doi.org/10.1029/2005JD006076, 2006. a
Matsui, H., Kondo, Y., Moteki, N., Takegawa, N., Sahu, L. K., Zhao, Y.,
Fuelberg, H. E., Sessions, W. R., Diskin, G., Blake, D. R., Wisthaler, A.,
and Koike, M.: Seasonal variation of the transport of black carbon aerosol
from the Asian continent to the Arctic during the ARCTAS aircraft campaign,
J. Geophys. Res.-Atmos., 116, D05202,
https://doi.org/10.1029/2010JD015067, 2011. a
Müller, S., Hoor, P., Bozem, H., Gute, E., Vogel, B., Zahn, A., Bönisch, H., Keber, T., Krämer, M., Rolf, C., Riese, M., Schlager, H., and Engel, A.: Impact of the Asian monsoon on the extratropical lower stratosphere: trace gas observations during TACTS over Europe 2012, Atmos. Chem. Phys., 16, 10573–10589, https://doi.org/10.5194/acp-16-10573-2016, 2016. a, b
Ninomiya, K. and Shibagaki, Y.: Multi-Scale Features of the Meiyu-Baiu Front
and Associated Precipitation Systems, J. Meteorol. Soc. Jpn., 85B, 103–122, https://doi.org/10.2151/jmsj.85B.103,
2007. a
Reidmiller, D. R., Jaffe, D. A., Fischer, E. V., and Finley, B.: Nitrogen oxides in the boundary layer and free troposphere at the Mt. Bachelor Observatory, Atmos. Chem. Phys., 10, 6043–6062, https://doi.org/10.5194/acp-10-6043-2010, 2010. a
Roiger, A., Schlager, H., Schäfler, A., Huntrieser, H., Scheibe, M., Aufmhoff, H., Cooper, O. R., Sodemann, H., Stohl, A., Burkhart, J., Lazzara, M., Schiller, C., Law, K. S., and Arnold, F.: In-situ observation of Asian pollution transported into the Arctic lowermost stratosphere, Atmos. Chem. Phys., 11, 10975–10994, https://doi.org/10.5194/acp-11-10975-2011, 2011. a
Santee, M. L., Manney, G. L., Livesey, N. J., Schwartz, M. J., Neu, J. L., and
Read, W. G.: A comprehensive overview of the climatological composition of
the Asian summer monsoon anticyclone based on 10 years of Aura Microwave
Limb Sounder measurements, J. Geophys. Res.-Atmos., 122,
5491–5514, https://doi.org/10.1002/2016JD026408, 2017. a
Schemm, S., Sprenger, M., and Wernli, H.: When during their life cycle are
extratropical cyclones attended by fronts?, B. Am. Meteorol. Soc., 99, 149–165, https://doi.org/10.1175/BAMS-D-16-0261.1, 2017. a
slcs-jsc: mptrac, GitHub, https://github.com/slcs-jsc/mptrac#readme, last access: May 2022. a
Thomas, C. and Schultz, D.: What are the Best Thermodynamic Quantity and
Function to Define a Front in Gridded Model Output?, B. Am. Meteorol. Soc., 100, 873–895, https://doi.org/10.1175/BAMS-D-18-0137.1, 2018. a
Tomsche, L., Pozzer, A., Ojha, N., Parchatka, U., Lelieveld, J., and Fischer, H.: Upper tropospheric CH4 and CO affected by the South Asian summer monsoon during the Oxidation Mechanism Observations mission, Atmos. Chem. Phys., 19, 1915–1939, https://doi.org/10.5194/acp-19-1915-2019, 2019. a
Turquety, S., Clerbaux, C., Law, K., Coheur, P.-F., Cozic, A., Szopa, S., Hauglustaine, D. A., Hadji-Lazaro, J., Gloudemans, A. M. S., Schrijver, H., Boone, C. D., Bernath, P. F., and Edwards, D. P.: CO emission and export from Asia: an analysis combining complementary satellite measurements (MOPITT, SCIAMACHY and ACE-FTS) with global modeling, Atmos. Chem. Phys., 8, 5187–5204, https://doi.org/10.5194/acp-8-5187-2008, 2008. a
Vogel, B., Günther, G., Müller, R., Grooß, J.-U., Hoor, P., Krämer, M., Müller, S., Zahn, A., and Riese, M.: Fast transport from Southeast Asia boundary layer sources to northern Europe: rapid uplift in typhoons and eastward eddy shedding of the Asian monsoon anticyclone, Atmos. Chem. Phys., 14, 12745–12762, https://doi.org/10.5194/acp-14-12745-2014, 2014. a
Vogel, B., Günther, G., Müller, R., Grooß, J.-U., Afchine, A., Bozem, H., Hoor, P., Krämer, M., Müller, S., Riese, M., Rolf, C., Spelten, N., Stiller, G. P., Ungermann, J., and Zahn, A.: Long-range transport pathways of tropospheric source gases originating in Asia into the northern lower stratosphere during the Asian monsoon season 2012, Atmos. Chem. Phys., 16, 15301–15325, https://doi.org/10.5194/acp-16-15301-2016, 2016. a
Wernli, H.: A lagrangian-based analysis of extratropical cyclones. II: A
detailed case-study, Q. J. Roy. Meteor. Soc.,
123, 1677–1706, https://doi.org/10.1002/qj.49712354211, 1997. a
Wernli, H. and Davies, H.: A Lagrangian-based analysis of extratropical
cyclones. I: The method and some applications, Q. J. Roy. Meteor. Soc., 123, 467–489, https://doi.org/10.1002/qj.49712353811, 1997. a
Wernli, H. and Schwierz, C.: Surface Cyclones in the ERA-40 Dataset
(1958–2001). Part I: Novel Identification Method and Global Climatology,
J. Atmos. Sci., 63, 2486–2507, https://doi.org/10.1175/JAS3766.1,
2006. a
Wilcox, L., Hoskins, B., and Shine, K.: A global blended tropopause based on
ERA data. Part I: Climatology, Q. J. Roy. Meteor. Soc., 138, 561–575, https://doi.org/10.1002/qj.951, 2012.
a
Wuebbles, D. J., Lei, H., and Lin, J.: Intercontinental transport of aerosols
and photochemical oxidants from Asia and its consequences, Environ. Pollut., 150, 65–84, https://doi.org/10.1016/j.envpol.2007.06.066,
2007. a
Yienger, J., Hastings, M., Holloway, T., Phadnis, M., Guttikunda, S.,
Carmichael, G., Moxim, W., and Levy, H.: The Episodic Nature of Air Pollution
Transport From Asia to North America, J. Geophys. Res., 105,
26931–26946, https://doi.org/10.1029/2000JD900309, 2000. a
Yihui, D. and Chan, J.: The East Asian summer monsoon: An overview, Meteorol. Atmos. Phys., 89, 117–142, https://doi.org/10.1007/s00703-005-0125-z, 2005. a
Yoon, J., Pozzer, A., Hoor, P., Chang, D. Y., Beirle, S., Wagner, T., Schloegl, S., Lelieveld, J., and Worden, H. M.: Technical Note: Temporal change in averaging kernels as a source of uncertainty in trend estimates of carbon monoxide retrieved from MOPITT, Atmos. Chem. Phys., 13, 11307–11316, https://doi.org/10.5194/acp-13-11307-2013, 2013. a
Yu, H., Remer, L., Chin, M., Bian, H., Kleidman, R., and Diehl, T.: A
satellite-based assessment of transpacific transport of pollution aerosol,
J. Geophys. Res., 113, D14S12, https://doi.org/10.1029/2007JD009349, 2008. a, b, c
Yu, P., Rosenlof, K. H., Liu, S., Telg, H., Thornberry, T. D., Rollins, A. W.,
Portmann, R. W., Bai, Z., Ray, E. A., Duan, Y., Pan, L. L., Toon, O. B.,
Bian, J., and Gao, R.-S.: Efficient transport of tropospheric aerosol into
the stratosphere via the Asian summer monsoon anticyclone, P. Natl. Acad. Sci. USA, 114, 6972–6977, https://doi.org/10.1073/pnas.1701170114,
2017. a
Yu, Y., Kalashnikova, O. V., Garay, M. J., and Notaro, M.: Climatology of Asian dust activation and transport potential based on MISR satellite observations and trajectory analysis, Atmos. Chem. Phys., 19, 363–378, https://doi.org/10.5194/acp-19-363-2019, 2019. a
Zhang, L., Jacob, D. J., Boersma, K. F., Jaffe, D. A., Olson, J. R., Bowman, K. W., Worden, J. R., Thompson, A. M., Avery, M. A., Cohen, R. C., Dibb, J. E., Flock, F. M., Fuelberg, H. E., Huey, L. G., McMillan, W. W., Singh, H. B., and Weinheimer, A. J.: Transpacific transport of ozone pollution and the effect of recent Asian emission increases on air quality in North America: an integrated analysis using satellite, aircraft, ozonesonde, and surface observations, Atmos. Chem. Phys., 8, 6117–6136, https://doi.org/10.5194/acp-8-6117-2008, 2008. a, b, c
Short summary
Our study presents a detailed analysis of the spatial and temporal distribution of elevated CO level in the upper troposphere over the Pacific using 20 years of MOPITT data. We create a climatology of severe pollution episodes and use trajectory calculations to link each particular pollution event detected in MOPITT satellite data with a distinct source region. Additionally, we analyse uplift mechanisms such as WCB-related upward transport.
Our study presents a detailed analysis of the spatial and temporal distribution of elevated CO...
Altmetrics
Final-revised paper
Preprint