Articles | Volume 21, issue 16
https://doi.org/10.5194/acp-21-12757-2021
© Author(s) 2021. 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-21-12757-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
30 Aug 2021
Research article |
| 30 Aug 2021
| 30 Aug 2021
Southern Ocean latitudinal gradients of cloud condensation nuclei
Ruhi S. Humphries
CORRESPONDING AUTHOR
Climate Science Centre, CSIRO Oceans and Atmosphere, Melbourne, Australia
Australian Antarctic Program Partnership, Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
Melita D. Keywood
Climate Science Centre, CSIRO Oceans and Atmosphere, Melbourne, Australia
Australian Antarctic Program Partnership, Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
Sean Gribben
Climate Science Centre, CSIRO Oceans and Atmosphere, Melbourne, Australia
Ian M. McRobert
Engineering and Technology Program, CSIRO National Collections and Marine Infrastructure, Hobart, Australia
Jason P. Ward
Climate Science Centre, CSIRO Oceans and Atmosphere, Melbourne, Australia
Paul Selleck
Climate Science Centre, CSIRO Oceans and Atmosphere, Melbourne, Australia
Sally Taylor
Climate Science Centre, CSIRO Oceans and Atmosphere, Melbourne, Australia
James Harnwell
Climate Science Centre, CSIRO Oceans and Atmosphere, Melbourne, Australia
Connor Flynn
School of Meteorology, University of Oklahoma, Norman, United States of America
Gourihar R. Kulkarni
Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, United States of America
Gerald G. Mace
Department of Atmospheric Science, University of Utah, Salt Lake City, United States of America
Alain Protat
Australian Bureau of Meteorology, Melbourne, Australia
Australian Antarctic Program Partnership, Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
Simon P. Alexander
Australian Antarctic Division, Channel Highway, Kingston, Tasmania 7050, Australia
Australian Antarctic Program Partnership, Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
Greg McFarquhar
School of Meteorology, University of Oklahoma, Norman, United States of America
Cooperative Institute for Mesoscale Meteorological Studies, University of Oklahoma, Norman, United States of America
Related authors
Caleb Mynard, Emily B. Franklin, Joel Alroe, Karen Westwood, Brandon J. McNabb, Robert Strzepek, Philippe D. Tortell, Steven T. Siems, Antonio Patti, Suzie Molloy, Alan Griffiths, Branka Miljevic, Marc D. Mallet, Ruhi Humphries, and Erin Dunne
EGUsphere, https://doi.org/10.5194/egusphere-2026-1346, https://doi.org/10.5194/egusphere-2026-1346, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
Marine sulfur gases help form climate-cooling particles, but their controls over the Southern Ocean are unclear. During a summer research voyage we measured these gases and linked them to ocean and atmospheric conditions. Near Antarctica, coastal blooms drove sharp rises in dimethyl sulfide while methanethiol remained low. Over the open ocean, both gases varied together, mainly influenced by ocean mixing and temperature, suggesting models should treat coastal and open ocean regions separately.
Sonya L. Fiddes, Matthew T. Woodhouse, Marc D. Mallet, Liam J. Lamprey, Ruhi S. Humphries, Alain Protat, Simon P. Alexander, Hakase Hayashida, Samuel Putland, Branka Miljevic, and Robyn Schofield
Atmos. Chem. Phys., 25, 16451–16477, https://doi.org/10.5194/acp-25-16451-2025, https://doi.org/10.5194/acp-25-16451-2025, 2025
Short summary
Short summary
The interaction between natural marine aerosols, clouds and radiation in the Southern Ocean is a major source of uncertainty in climate models. We evaluate the Australian climate model using aerosol observations and find it underestimates aerosol number often by over 50%. Model changes were tested to improve aerosol concentrations, but some of our changes had severe negative effects on the larger climate system, highlighting issues in aerosol-cloud interaction modelling.
Jhonathan Ramirez-Gamboa, Clare Paton-Walsh, Melita Keywood, Ruhi Humphries, Asher Mouat, Jennifer Kaiser, Malcom Possell, Jack Simmons, and Travis Naylor
Atmos. Chem. Phys., 25, 9937–9955, https://doi.org/10.5194/acp-25-9937-2025, https://doi.org/10.5194/acp-25-9937-2025, 2025
Short summary
Short summary
Tiny air particles (aerosols) influence clouds, sunlight, and air chemistry. Our study examined how these particles form in a plant-rich region of Southeast Australia. We found frequent new particle formation (NPF) events, often linked to pollution plumes. Volatile organic compounds (VOCs) from plants and other factors influence NPF and aerosol growth. Nighttime NPF requires further study. Overall, plant emissions play a key role in aerosol formation in this region.
Tahereh Alinejadtabrizi, Yi Huang, Francisco Lang, Steven Siems, Michael Manton, Luis Ackermann, Melita Keywood, Ruhi Humphries, Paul Krummel, Alastair Williams, and Greg Ayers
Atmos. Chem. Phys., 25, 2631–2648, https://doi.org/10.5194/acp-25-2631-2025, https://doi.org/10.5194/acp-25-2631-2025, 2025
Short summary
Short summary
Clouds over the Southern Ocean are crucial to Earth's energy balance, but understanding the factors that control them is complex. Our research examines how weather patterns affect tiny particles called cloud condensation nuclei (CCN), which influence cloud properties. Using data from Kennaook / Cape Grim, we found that winter air from Antarctica brings cleaner conditions with lower CCN, while summer patterns from Australia transport more particles. Precipitation also helps reduce CCN in winter.
Ruhi S. Humphries, Melita D. Keywood, Jason P. Ward, James Harnwell, Simon P. Alexander, Andrew R. Klekociuk, Keiichiro Hara, Ian M. McRobert, Alain Protat, Joel Alroe, Luke T. Cravigan, Branka Miljevic, Zoran D. Ristovski, Robyn Schofield, Stephen R. Wilson, Connor J. Flynn, Gourihar R. Kulkarni, Gerald G. Mace, Greg M. McFarquhar, Scott D. Chambers, Alastair G. Williams, and Alan D. Griffiths
Atmos. Chem. Phys., 23, 3749–3777, https://doi.org/10.5194/acp-23-3749-2023, https://doi.org/10.5194/acp-23-3749-2023, 2023
Short summary
Short summary
Observations of aerosols in pristine regions are rare but are vital to constraining the natural baseline from which climate simulations are calculated. Here we present recent seasonal observations of aerosols from the Southern Ocean and contrast them with measurements from Antarctica, Australia and regionally relevant voyages. Strong seasonal cycles persist, but striking differences occur at different latitudes. This study highlights the need for more long-term observations in remote regions.
Gerald G. Mace, Sally Benson, Ruhi Humphries, Peter M. Gombert, and Elizabeth Sterner
Atmos. Chem. Phys., 23, 1677–1685, https://doi.org/10.5194/acp-23-1677-2023, https://doi.org/10.5194/acp-23-1677-2023, 2023
Short summary
Short summary
The number of cloud droplets per unit volume is a significantly important property of clouds that controls their reflective properties. Computer models of the Earth's atmosphere and climate have low skill at predicting the reflective properties of Southern Ocean clouds. Here we investigate the properties of those clouds using satellite data and find that the cloud droplet number and cloud albedo in the Southern Ocean are related to the oceanic phytoplankton abundance near Antarctica.
Sonya L. Fiddes, Matthew T. Woodhouse, Steve Utembe, Robyn Schofield, Simon P. Alexander, Joel Alroe, Scott D. Chambers, Zhenyi Chen, Luke Cravigan, Erin Dunne, Ruhi S. Humphries, Graham Johnson, Melita D. Keywood, Todd P. Lane, Branka Miljevic, Yuko Omori, Alain Protat, Zoran Ristovski, Paul Selleck, Hilton B. Swan, Hiroshi Tanimoto, Jason P. Ward, and Alastair G. Williams
Atmos. Chem. Phys., 22, 2419–2445, https://doi.org/10.5194/acp-22-2419-2022, https://doi.org/10.5194/acp-22-2419-2022, 2022
Short summary
Short summary
Coral reefs have been found to produce the climatically relevant chemical compound dimethyl sulfide (DMS). It has been suggested that corals can modify their environment via the production of DMS. We use an atmospheric chemistry model to test this theory at a regional scale for the first time. We find that it is unlikely that coral-reef-derived DMS has an influence over local climate, in part due to the proximity to terrestrial and anthropogenic aerosol sources.
Christopher R. Oxford, Haihui Zhu, Maya Mehrotra, Xuan Liu, Yuxuan Ren, Maya Arnott, Isaac Abionum Adimula, Taiye Benjamin Ajibolataiye, Clement Akoshile, Omar Amador-Munoz, Araya Asfaw, Rachel Ying-Wen Chang, Sagnik Dey, Ann M. Dillner, David J. Diner, Connor J. Flynn, Diana Francis, Paterne Gahungu, Rebecca M. Garland, Michel Grutter, Sina Hasheminassab, Fahad Imam, Jhoon Kim, Kristy Langerman, Pei-Chen Lee, Puji Lestari, Po-Hsiung Lin, S. Marcela Loria-Salazar, Tesfaye Mamo, Olga L. Mayol-Bracero, Mogesh Naidoo, Narendra Nelli, Sang Seo Park, Abdus Salam, Bighnaraj Sarangi, Trailokya Saud, Robyn Schofield, Yoav Schechner, Sachchida N. Tripathi, Emily K. West, Eli Windwer, Ming-Tsang Wu, Qiang Zhang, Michael Brauer, Yinon Rudich, Jay R. Turner, and Randall V. Martin
EGUsphere, https://doi.org/10.5194/egusphere-2026-3224, https://doi.org/10.5194/egusphere-2026-3224, 2026
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
Short summary
Short summary
A high-sensitivity balance, controlled temperature and relative humidity chamber, and filter samples collected around the world were used to develop a mass as a function of relative humidity relationship. We subsequently measured the chemical composition of these same samples. A relationship between the chemical composition and water mass was created and used to calculate aerosol water content showing how composition and water content varies worldwide.
Samuel Ephraim, Paquita Zuidema, Aaron Bansemer, Lintong Cai, Markus Petters, Elise Rosky, Jefferson R. Snider, Zhien Wang, Sarah Woods, Kevin Barry, Theresa Campos, Owen Cruikshank, Sabine Eckhardt, Nikolaos Evangeliou, Romanos Foskinis, Jeffrey R. French, Bart Geerts, Coltin Grasmick, Silvia Henning, Varun Kumar, Andreas Massling, Camille Mavis, Greg M. McFarquhar, Athanasios Nenes, Gunnar Noer, Ryan Patnaude, Russell Perkins, Lise Lotte Sorensen, Henrik Skov, Tyler Tatro, Florian Tornow, and Lu Zhang
EGUsphere, https://doi.org/10.5194/egusphere-2026-2940, https://doi.org/10.5194/egusphere-2026-2940, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
The processes that establish how mixed-phase closed-cell clouds transition to more open cellular structures are poorly known. First-of-its kind aircraft observations document such a transition in the presence of anomalously high aerosol concentrations over the Nordic Seas at cloud temperatures < -15 °C. The reduces the drop size, discouraging riming. Eventually, ice precipitation produces surface cold pools that drive the convective transition, despite strong counteracting surface fluxes.
Adrien Guyot, Jacob Vile, Louis Soulard-Fischer, Hamish McGowan, Alain Protat, and Caroline Poulsen
EGUsphere, https://doi.org/10.5194/egusphere-2026-1907, https://doi.org/10.5194/egusphere-2026-1907, 2026
Short summary
Short summary
We studied how extreme wildfire clouds are detected from space and compared this with weather radar and lightning observations. We found that satellites can reliably detect when these clouds begin, but later tend to track spreading cloud tops rather than the active storm itself. This can make events appear larger and longer-lasting than they are. Combining different types of observations is therefore essential to better understand and monitor these dangerous fire-driven storms.
Jingjing Tian, Gourihar Kulkarni, Jennifer M. Comstock, John E. Shilling, Damao Zhang, Peng Wu, and Fan Mei
EGUsphere, https://doi.org/10.5194/egusphere-2026-1432, https://doi.org/10.5194/egusphere-2026-1432, 2026
Short summary
Short summary
Cloud condensation nuclei are tiny particles that attract water vapor and help form clouds. A ground-based lidar method can estimate their number at different heights, but assumes the aerosol type does not change with height. Comparisons with aircraft data show good agreement of this method when aerosols are well mixed, but larger errors when stacked layers occur. We also developed an index to flag these complex conditions and indicate when this estimation method is more reliable.
Jonas Witthuhn, Hartwig Deneke, Andreas Macke, Oscar Ritter, Jens Redemann, Connor J. Flynn, Abdulamid A. Fakoya, Bradley F. Lamkin, Emily D. Lenhardt, Logan T. Mitchell, Emily K. West, David M. Romps, Rusen Öktem, and Heike Kalesse-Los
Atmos. Chem. Phys., 26, 5727–5745, https://doi.org/10.5194/acp-26-5727-2026, https://doi.org/10.5194/acp-26-5727-2026, 2026
Short summary
Short summary
This study examines how solar irradiance changes when sunlight passes from clear sky into cloud shadows, focusing on 3‑D radiative effects of shallow cumulus clouds. Using data from a dense pyranometer network and cloud masks from cameras we found that irradiance can rise up to 20 % above clear‑sky levels near cloud edges. Key drivers include sun‑cloud geometry and microphysical cloud properties. The results highlight the need to incorporate such 3‑D effects in atmospheric models.
Caleb Mynard, Emily B. Franklin, Joel Alroe, Karen Westwood, Brandon J. McNabb, Robert Strzepek, Philippe D. Tortell, Steven T. Siems, Antonio Patti, Suzie Molloy, Alan Griffiths, Branka Miljevic, Marc D. Mallet, Ruhi Humphries, and Erin Dunne
EGUsphere, https://doi.org/10.5194/egusphere-2026-1346, https://doi.org/10.5194/egusphere-2026-1346, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
Marine sulfur gases help form climate-cooling particles, but their controls over the Southern Ocean are unclear. During a summer research voyage we measured these gases and linked them to ocean and atmospheric conditions. Near Antarctica, coastal blooms drove sharp rises in dimethyl sulfide while methanethiol remained low. Over the open ocean, both gases varied together, mainly influenced by ocean mixing and temperature, suggesting models should treat coastal and open ocean regions separately.
Scott Edward Giangrande, Christopher R. Williams, and Alain Protat
EGUsphere, https://doi.org/10.5194/egusphere-2026-856, https://doi.org/10.5194/egusphere-2026-856, 2026
Short summary
Short summary
Better characterization of precipitation characteristics has important implications for simulated storm behaviors and remotely-sensed retrievals of cloud intensity. We use a unique radar technique to estimate the fall speeds of media found within deep tropical clouds. These retrievals can be performed within intense storm conditions that are otherwise impractical to sample. Our observations suggest mixed media or graupel fall speeds are contextually faster than prior references.
Logan T. Mitchell, Connor J. Flynn, Kristina Pistone, Samuel E. LeBlanc, K. Sebastian Schmidt, Hong Chen, Paquita Zuidema, Robert Wood, and Jens Redemann
EGUsphere, https://doi.org/10.5194/egusphere-2026-1418, https://doi.org/10.5194/egusphere-2026-1418, 2026
Short summary
Short summary
During 2016–2018, NASA conducted an airborne field campaign over the Southeast Atlantic Ocean to study biomass burning aerosols emitted from Southern African fires. We have found that aerosol scattering increases over the course of the emission season, which is due to a compositional change within black carbon as the source fires shift southeastward, rather than an increase in brown carbon. This aerosol brightening is also noted within a 30-year aerosol climatology from ground-based stations.
Emily D. Lenhardt, Lan Gao, Siddhant Gupta, Greg M. McFarquhar, Feng Xu, Richard A. Ferrare, Chris A. Hostetler, and Jens Redemann
EGUsphere, https://doi.org/10.5194/egusphere-2026-853, https://doi.org/10.5194/egusphere-2026-853, 2026
Short summary
Short summary
Interactions between clouds and small particles in the atmosphere can cause changes to cloud properties such as how much of the sun's energy they reflect and whether precipitation is likely to occur. Here we use a new machine learning dataset to investigate these interactions using observations from the Southeast Atlantic. We find that smoke particles above cloud tops have a stronger impact on cloud properties than particles below clouds. This method can also be applied to satellite data.
Gerald G. Mace, Sally Benson, Peter Gombert, and Tiffany Smallwood
Atmos. Chem. Phys., 26, 1041–1051, https://doi.org/10.5194/acp-26-1041-2026, https://doi.org/10.5194/acp-26-1041-2026, 2026
Short summary
Short summary
The amount of sunlight reflected by marine boundary layer clouds in the Eastern North Atlantic does not change due to a decrease in aerosol caused by reduced sulphur in shipping fuel because adjustments to liquid water path offset the decease in cloud droplet number concentration.
Sonya L. Fiddes, Matthew T. Woodhouse, Marc D. Mallet, Liam J. Lamprey, Ruhi S. Humphries, Alain Protat, Simon P. Alexander, Hakase Hayashida, Samuel Putland, Branka Miljevic, and Robyn Schofield
Atmos. Chem. Phys., 25, 16451–16477, https://doi.org/10.5194/acp-25-16451-2025, https://doi.org/10.5194/acp-25-16451-2025, 2025
Short summary
Short summary
The interaction between natural marine aerosols, clouds and radiation in the Southern Ocean is a major source of uncertainty in climate models. We evaluate the Australian climate model using aerosol observations and find it underestimates aerosol number often by over 50%. Model changes were tested to improve aerosol concentrations, but some of our changes had severe negative effects on the larger climate system, highlighting issues in aerosol-cloud interaction modelling.
Logan T. Mitchell, Connor J. Flynn, Kristina Pistone, Samuel E. LeBlanc, K. Sebastian Schmidt, and Jens Redemann
Earth Syst. Sci. Data, 17, 5303–5313, https://doi.org/10.5194/essd-17-5303-2025, https://doi.org/10.5194/essd-17-5303-2025, 2025
Short summary
Short summary
During 2016–2018, NASA conducted an airborne field campaign over the Southeast Atlantic Ocean to study biomass burning aerosols emitted from Southern African fires. These aerosols then interact with stratocumulus clouds over the Southeast Atlantic, which is difficult for climate models to account for. Our instrument, 4STAR, determines aerosol radiative properties. A dataset was already created for 2016, but additional quality control was required to address instrument issues for 2017 and 2018.
Jhonathan Ramirez-Gamboa, Clare Paton-Walsh, Melita Keywood, Ruhi Humphries, Asher Mouat, Jennifer Kaiser, Malcom Possell, Jack Simmons, and Travis Naylor
Atmos. Chem. Phys., 25, 9937–9955, https://doi.org/10.5194/acp-25-9937-2025, https://doi.org/10.5194/acp-25-9937-2025, 2025
Short summary
Short summary
Tiny air particles (aerosols) influence clouds, sunlight, and air chemistry. Our study examined how these particles form in a plant-rich region of Southeast Australia. We found frequent new particle formation (NPF) events, often linked to pollution plumes. Volatile organic compounds (VOCs) from plants and other factors influence NPF and aerosol growth. Nighttime NPF requires further study. Overall, plant emissions play a key role in aerosol formation in this region.
Abdulamid A. Fakoya, Jens Redemann, Pablo E. Saide, Lan Gao, Logan T. Mitchell, Calvin Howes, Amie Dobracki, Ian Chang, Gonzalo A. Ferrada, Kristina Pistone, Samuel E. Leblanc, Michal Segal-Rozenhaimer, Arthur J. Sedlacek III, Thomas Eck, Brent Holben, Pawan Gupta, Elena Lind, Paquita Zuidema, Gregory Carmichael, and Connor J. Flynn
Atmos. Chem. Phys., 25, 7879–7902, https://doi.org/10.5194/acp-25-7879-2025, https://doi.org/10.5194/acp-25-7879-2025, 2025
Short summary
Short summary
Tiny atmospheric particles from wildfire smoke impact the climate by interacting with sunlight and clouds, the extent of which is uncertain due to gaps in understanding how smoke changes over time. We developed a new method using remote sensing instruments to track how these particles evolve during atmospheric transport. Our results show that the ability of these particles to absorb sunlight increases as they travel. This discovery could help improve predictions of future climate scenarios.
Fan Mei, Qi Zhang, Damao Zhang, Jerome D. Fast, Gourihar Kulkarni, Mikhail S. Pekour, Christopher R. Niedek, Susanne Glienke, Israel Silber, Beat Schmid, Jason M. Tomlinson, Hardeep S. Mehta, Xena Mansoura, Zezhen Cheng, Gregory W. Vandergrift, Nurun Nahar Lata, Swarup China, and Zihua Zhu
Atmos. Chem. Phys., 25, 3425–3444, https://doi.org/10.5194/acp-25-3425-2025, https://doi.org/10.5194/acp-25-3425-2025, 2025
Short summary
Short summary
This study highlights the unique capability of the ArcticShark, an uncrewed aerial system, in measuring vertically resolved atmospheric properties. Data from 32 research flights in 2023 reveal seasonal patterns and correlations with conventional measurements. The consistency and complementarity of in situ and remote sensing methods are highlighted. The study demonstrates the ArcticShark’s versatility in bridging data gaps and improving the understanding of vertical atmospheric structures.
Tahereh Alinejadtabrizi, Yi Huang, Francisco Lang, Steven Siems, Michael Manton, Luis Ackermann, Melita Keywood, Ruhi Humphries, Paul Krummel, Alastair Williams, and Greg Ayers
Atmos. Chem. Phys., 25, 2631–2648, https://doi.org/10.5194/acp-25-2631-2025, https://doi.org/10.5194/acp-25-2631-2025, 2025
Short summary
Short summary
Clouds over the Southern Ocean are crucial to Earth's energy balance, but understanding the factors that control them is complex. Our research examines how weather patterns affect tiny particles called cloud condensation nuclei (CCN), which influence cloud properties. Using data from Kennaook / Cape Grim, we found that winter air from Antarctica brings cleaner conditions with lower CCN, while summer patterns from Australia transport more particles. Precipitation also helps reduce CCN in winter.
Kerry Meyer, Steven Platnick, G. Thomas Arnold, Nandana Amarasinghe, Daniel Miller, Jennifer Small-Griswold, Mikael Witte, Brian Cairns, Siddhant Gupta, Greg McFarquhar, and Joseph O'Brien
Atmos. Meas. Tech., 18, 981–1011, https://doi.org/10.5194/amt-18-981-2025, https://doi.org/10.5194/amt-18-981-2025, 2025
Short summary
Short summary
Satellite remote sensing retrievals of cloud droplet size are used to understand clouds and their interactions with aerosols and radiation but require many simplifying assumptions. Evaluation of these retrievals is typically done by comparing against direct measurements of droplets from airborne cloud probes. This paper details an evaluation of proxy airborne remote sensing droplet size retrievals against several cloud probes and explores the impact of key assumptions on retrieval agreement.
Jeonggyu Kim, Sungmin Park, Greg M. McFarquhar, Anthony J. Baran, Joo Wan Cha, Kyoungmi Lee, Seoung Soo Lee, Chang Hoon Jung, Kyo-Sun Sunny Lim, and Junshik Um
Atmos. Chem. Phys., 24, 12707–12726, https://doi.org/10.5194/acp-24-12707-2024, https://doi.org/10.5194/acp-24-12707-2024, 2024
Short summary
Short summary
We developed idealized models to represent the shapes of ice particles found in deep convective clouds and calculated their single-scattering properties. By comparing these results with in situ measurements, we discovered that a mixture of shape models matches in situ measurements more closely than single-form models or aggregate models. This finding has important implications for enhancing the simulation of single-scattering properties of ice crystals in deep convective clouds.
Alexei Korolev, Zhipeng Qu, Jason Milbrandt, Ivan Heckman, Mélissa Cholette, Mengistu Wolde, Cuong Nguyen, Greg M. McFarquhar, Paul Lawson, and Ann M. Fridlind
Atmos. Chem. Phys., 24, 11849–11881, https://doi.org/10.5194/acp-24-11849-2024, https://doi.org/10.5194/acp-24-11849-2024, 2024
Short summary
Short summary
The phenomenon of high ice water content (HIWC) occurs in mesoscale convective systems (MCSs) when a large number of small ice particles with typical sizes of a few hundred micrometers is found at high altitudes. It was found that secondary ice production in the vicinity of the melting layer plays a key role in the formation and maintenance of HIWC. This study presents a conceptual model of the formation of HIWC in tropical MCSs based on in situ observations and numerical simulation.
Evgueni Kassianov, Connor J. Flynn, James C. Barnard, Brian D. Ermold, and Jennifer M. Comstock
Atmos. Meas. Tech., 17, 4997–5013, https://doi.org/10.5194/amt-17-4997-2024, https://doi.org/10.5194/amt-17-4997-2024, 2024
Short summary
Short summary
Conventional ground-based radiometers commonly measure solar radiation at a few wavelengths within a narrow spectral range. These limitations prevent improved retrievals of aerosol, cloud, and surface characteristics. To address these limitations, an advanced ground-based radiometer with expanded spectral coverage and hyperspectral capability is introduced. Its good performance is demonstrated using reference data collected over three coastal regions with diverse types of aerosols and clouds.
Kelly A. Balmes, Laura D. Riihimaki, John Wood, Connor Flynn, Adam Theisen, Michael Ritsche, Lynn Ma, Gary B. Hodges, and Christian Herrera
Atmos. Meas. Tech., 17, 3783–3807, https://doi.org/10.5194/amt-17-3783-2024, https://doi.org/10.5194/amt-17-3783-2024, 2024
Short summary
Short summary
A new hyperspectral radiometer (HSR1) was deployed and evaluated in the central United States (northern Oklahoma). The HSR1 total spectral irradiance agreed well with nearby existing instruments, but the diffuse spectral irradiance was slightly smaller. The HSR1-retrieved aerosol optical depth (AOD) also agreed well with other retrieved AODs. The HSR1 performance is encouraging: new hyperspectral knowledge is possible that could inform atmospheric process understanding and weather forecasting.
Gerald G. Mace
Atmos. Meas. Tech., 17, 3679–3695, https://doi.org/10.5194/amt-17-3679-2024, https://doi.org/10.5194/amt-17-3679-2024, 2024
Short summary
Short summary
The number of cloud droplets per unit volume, Nd, in a cloud is important for understanding aerosol–cloud interaction. In this study, we develop techniques to derive cloud droplet number concentration from lidar measurements combined with other remote sensing measurements such as cloud radar and microwave radiometers. We show that deriving Nd is very uncertain, although a synergistic algorithm seems to produce useful characterizations of Nd and effective particle size.
Michie Vianca De Vera, Larry Di Girolamo, Guangyu Zhao, Robert M. Rauber, Stephen W. Nesbitt, and Greg M. McFarquhar
Atmos. Chem. Phys., 24, 5603–5623, https://doi.org/10.5194/acp-24-5603-2024, https://doi.org/10.5194/acp-24-5603-2024, 2024
Short summary
Short summary
Tropical oceanic low clouds remain a dominant source of uncertainty in cloud feedback in climate models due to their macrophysical properties (fraction, size, height, shape, distribution) being misrepresented. High-resolution satellite imagery over the Philippine oceans is used here to characterize cumulus macrophysical properties and their relationship to meteorological variables. Such information can act as a benchmark for cloud models and can improve low-cloud generation in climate models.
Hiren T. Jethva, Omar Torres, Richard A. Ferrare, Sharon P. Burton, Anthony L. Cook, David B. Harper, Chris A. Hostetler, Jens Redemann, Vinay Kayetha, Samuel LeBlanc, Kristina Pistone, Logan Mitchell, and Connor J. Flynn
Atmos. Meas. Tech., 17, 2335–2366, https://doi.org/10.5194/amt-17-2335-2024, https://doi.org/10.5194/amt-17-2335-2024, 2024
Short summary
Short summary
We introduce a novel synergy algorithm applied to ORALCES airborne measurements of above-cloud aerosol optical depth and UV–Vis satellite observations from OMI and MODIS to retrieve spectral aerosol single-scattering albedo of lofted layers of carbonaceous smoke aerosols over clouds. The development of the proposed aerosol–cloud algorithm implies a possible synergy of CALIOP and OMI–MODIS passive sensors to deduce a global product of AOD and SSA of absorbing aerosols above clouds.
Sonya L. Fiddes, Marc D. Mallet, Alain Protat, Matthew T. Woodhouse, Simon P. Alexander, and Kalli Furtado
Geosci. Model Dev., 17, 2641–2662, https://doi.org/10.5194/gmd-17-2641-2024, https://doi.org/10.5194/gmd-17-2641-2024, 2024
Short summary
Short summary
In this study we present an evaluation that considers complex, non-linear systems in a holistic manner. This study uses XGBoost, a machine learning algorithm, to predict the simulated Southern Ocean shortwave radiation bias in the ACCESS model using cloud property biases as predictors. We then used a novel feature importance analysis to quantify the role that each cloud bias plays in predicting the radiative bias, laying the foundation for advanced Earth system model evaluation and development.
Luis Ackermann, Joshua Soderholm, Alain Protat, Rhys Whitley, Lisa Ye, and Nina Ridder
Atmos. Meas. Tech., 17, 407–422, https://doi.org/10.5194/amt-17-407-2024, https://doi.org/10.5194/amt-17-407-2024, 2024
Short summary
Short summary
The paper addresses the crucial topic of hail damage quantification using radar observations. We propose a new radar-derived hail product that utilizes a large dataset of insurance hail damage claims and radar observations. A deep neural network was employed, trained with local meteorological variables and the radar observations, to better quantify hail damage. Key meteorological variables were identified to have the most predictive capability in this regard.
Calvin Howes, Pablo E. Saide, Hugh Coe, Amie Dobracki, Steffen Freitag, Jim M. Haywood, Steven G. Howell, Siddhant Gupta, Janek Uin, Mary Kacarab, Chongai Kuang, L. Ruby Leung, Athanasios Nenes, Greg M. McFarquhar, James Podolske, Jens Redemann, Arthur J. Sedlacek, Kenneth L. Thornhill, Jenny P. S. Wong, Robert Wood, Huihui Wu, Yang Zhang, Jianhao Zhang, and Paquita Zuidema
Atmos. Chem. Phys., 23, 13911–13940, https://doi.org/10.5194/acp-23-13911-2023, https://doi.org/10.5194/acp-23-13911-2023, 2023
Short summary
Short summary
To better understand smoke properties and its interactions with clouds, we compare the WRF-CAM5 model with observations from ORACLES, CLARIFY, and LASIC field campaigns in the southeastern Atlantic in August 2017. The model transports and mixes smoke well but does not fully capture some important processes. These include smoke chemical and physical aging over 4–12 days, smoke removal by rain, sulfate particle formation, aerosol activation into cloud droplets, and boundary layer turbulence.
Adrien Guyot, Jordan P. Brook, Alain Protat, Kathryn Turner, Joshua Soderholm, Nicholas F. McCarthy, and Hamish McGowan
Atmos. Meas. Tech., 16, 4571–4588, https://doi.org/10.5194/amt-16-4571-2023, https://doi.org/10.5194/amt-16-4571-2023, 2023
Short summary
Short summary
We propose a new method that should facilitate the use of weather radars to study wildfires. It is important to be able to identify the particles emitted by wildfires on radar, but it is difficult because there are many other echoes on radar like clear air, the ground, sea clutter, and precipitation. We came up with a two-step process to classify these echoes. Our method is accurate and can be used by fire departments in emergencies or by scientists for research.
McKenna W. Stanford, Ann M. Fridlind, Israel Silber, Andrew S. Ackerman, Greg Cesana, Johannes Mülmenstädt, Alain Protat, Simon Alexander, and Adrian McDonald
Atmos. Chem. Phys., 23, 9037–9069, https://doi.org/10.5194/acp-23-9037-2023, https://doi.org/10.5194/acp-23-9037-2023, 2023
Short summary
Short summary
Clouds play an important role in the Earth’s climate system as they modulate the amount of radiation that either reaches the surface or is reflected back to space. This study demonstrates an approach to robustly evaluate surface-based observations against a large-scale model. We find that the large-scale model precipitates too infrequently relative to observations, contrary to literature documentation suggesting otherwise based on satellite measurements.
Rose Marie Miller, Robert M. Rauber, Larry Di Girolamo, Matthew Rilloraza, Dongwei Fu, Greg M. McFarquhar, Stephen W. Nesbitt, Luke D. Ziemba, Sarah Woods, and Kenneth Lee Thornhill
Atmos. Chem. Phys., 23, 8959–8977, https://doi.org/10.5194/acp-23-8959-2023, https://doi.org/10.5194/acp-23-8959-2023, 2023
Short summary
Short summary
The influence of human-produced aerosols on clouds remains one of the uncertainties in radiative forcing of Earth’s climate. Measurements of aerosol chemistry from sources around the Philippines illustrate the linkage between aerosol chemical composition and cloud droplet characteristics. Differences in aerosol chemical composition in the marine layer from biomass burning, industrial, ship-produced, and marine aerosols are shown to impact cloud microphysical structure just above cloud base.
Manon Rocco, Erin Dunne, Alexia Saint-Macary, Maija Peltola, Theresa Barthelmeß, Neill Barr, Karl Safi, Andrew Marriner, Stacy Deppeler, James Harnwell, Anja Engel, Aurélie Colomb, Alfonso Saiz-Lopez, Mike Harvey, Cliff S. Law, and Karine Sellegri
EGUsphere, https://doi.org/10.5194/egusphere-2023-516, https://doi.org/10.5194/egusphere-2023-516, 2023
Preprint archived
Short summary
Short summary
During the Sea2cloud campaign in the Southern Pacific Ocean, we measured air-sea emissions from phytopankton of two key atmospheric compounds: DMS and MeSH. These compounds are well-known to play a great role in atmospheric chemistry and climate. We see in this paper that these compounds are most emited by the nanophytoplankton population. We provide here parameters for climate models to predict future trends of the emissions of these compounds and their roles and impacts on the global warming.
Ian Chang, Lan Gao, Connor J. Flynn, Yohei Shinozuka, Sarah J. Doherty, Michael S. Diamond, Karla M. Longo, Gonzalo A. Ferrada, Gregory R. Carmichael, Patricia Castellanos, Arlindo M. da Silva, Pablo E. Saide, Calvin Howes, Zhixin Xue, Marc Mallet, Ravi Govindaraju, Qiaoqiao Wang, Yafang Cheng, Yan Feng, Sharon P. Burton, Richard A. Ferrare, Samuel E. LeBlanc, Meloë S. Kacenelenbogen, Kristina Pistone, Michal Segal-Rozenhaimer, Kerry G. Meyer, Ju-Mee Ryoo, Leonhard Pfister, Adeyemi A. Adebiyi, Robert Wood, Paquita Zuidema, Sundar A. Christopher, and Jens Redemann
Atmos. Chem. Phys., 23, 4283–4309, https://doi.org/10.5194/acp-23-4283-2023, https://doi.org/10.5194/acp-23-4283-2023, 2023
Short summary
Short summary
Abundant aerosols are present above low-level liquid clouds over the southeastern Atlantic during late austral spring. The model simulation differences in the proportion of aerosol residing in the planetary boundary layer and in the free troposphere can greatly affect the regional aerosol radiative effects. This study examines the aerosol loading and fractional aerosol loading in the free troposphere among various models and evaluates them against measurements from the NASA ORACLES campaign.
Francesca Gallo, Janek Uin, Kevin J. Sanchez, Richard H. Moore, Jian Wang, Robert Wood, Fan Mei, Connor Flynn, Stephen Springston, Eduardo B. Azevedo, Chongai Kuang, and Allison C. Aiken
Atmos. Chem. Phys., 23, 4221–4246, https://doi.org/10.5194/acp-23-4221-2023, https://doi.org/10.5194/acp-23-4221-2023, 2023
Short summary
Short summary
This study provides a summary statistic of multiday aerosol plume transport event influences on aerosol physical properties and the cloud condensation nuclei budget at the U.S. Department of Energy Atmospheric Radiation Measurement Facility in the eastern North Atlantic (ENA). An algorithm that integrates aerosol properties is developed and applied to identify multiday aerosol transport events. The influence of the aerosol plumes on aerosol populations at the ENA is successively assessed.
Ruhi S. Humphries, Melita D. Keywood, Jason P. Ward, James Harnwell, Simon P. Alexander, Andrew R. Klekociuk, Keiichiro Hara, Ian M. McRobert, Alain Protat, Joel Alroe, Luke T. Cravigan, Branka Miljevic, Zoran D. Ristovski, Robyn Schofield, Stephen R. Wilson, Connor J. Flynn, Gourihar R. Kulkarni, Gerald G. Mace, Greg M. McFarquhar, Scott D. Chambers, Alastair G. Williams, and Alan D. Griffiths
Atmos. Chem. Phys., 23, 3749–3777, https://doi.org/10.5194/acp-23-3749-2023, https://doi.org/10.5194/acp-23-3749-2023, 2023
Short summary
Short summary
Observations of aerosols in pristine regions are rare but are vital to constraining the natural baseline from which climate simulations are calculated. Here we present recent seasonal observations of aerosols from the Southern Ocean and contrast them with measurements from Antarctica, Australia and regionally relevant voyages. Strong seasonal cycles persist, but striking differences occur at different latitudes. This study highlights the need for more long-term observations in remote regions.
Gerald G. Mace, Sally Benson, Ruhi Humphries, Peter M. Gombert, and Elizabeth Sterner
Atmos. Chem. Phys., 23, 1677–1685, https://doi.org/10.5194/acp-23-1677-2023, https://doi.org/10.5194/acp-23-1677-2023, 2023
Short summary
Short summary
The number of cloud droplets per unit volume is a significantly important property of clouds that controls their reflective properties. Computer models of the Earth's atmosphere and climate have low skill at predicting the reflective properties of Southern Ocean clouds. Here we investigate the properties of those clouds using satellite data and find that the cloud droplet number and cloud albedo in the Southern Ocean are related to the oceanic phytoplankton abundance near Antarctica.
Sonya L. Fiddes, Alain Protat, Marc D. Mallet, Simon P. Alexander, and Matthew T. Woodhouse
Atmos. Chem. Phys., 22, 14603–14630, https://doi.org/10.5194/acp-22-14603-2022, https://doi.org/10.5194/acp-22-14603-2022, 2022
Short summary
Short summary
Climate models have difficulty simulating Southern Ocean clouds, impacting how much sunlight reaches the surface. We use machine learning to group different cloud types observed from satellites and simulated in a climate model. We find the model does a poor job of simulating the same cloud type as what the satellite shows and, even when it does, the cloud properties and amount of reflected sunlight are incorrect. We have a lot of work to do to model clouds correctly over the Southern Ocean.
Paul A. Barrett, Steven J. Abel, Hugh Coe, Ian Crawford, Amie Dobracki, James Haywood, Steve Howell, Anthony Jones, Justin Langridge, Greg M. McFarquhar, Graeme J. Nott, Hannah Price, Jens Redemann, Yohei Shinozuka, Kate Szpek, Jonathan W. Taylor, Robert Wood, Huihui Wu, Paquita Zuidema, Stéphane Bauguitte, Ryan Bennett, Keith Bower, Hong Chen, Sabrina Cochrane, Michael Cotterell, Nicholas Davies, David Delene, Connor Flynn, Andrew Freedman, Steffen Freitag, Siddhant Gupta, David Noone, Timothy B. Onasch, James Podolske, Michael R. Poellot, Sebastian Schmidt, Stephen Springston, Arthur J. Sedlacek III, Jamie Trembath, Alan Vance, Maria A. Zawadowicz, and Jianhao Zhang
Atmos. Meas. Tech., 15, 6329–6371, https://doi.org/10.5194/amt-15-6329-2022, https://doi.org/10.5194/amt-15-6329-2022, 2022
Short summary
Short summary
To better understand weather and climate, it is vital to go into the field and collect observations. Often measurements take place in isolation, but here we compared data from two aircraft and one ground-based site. This was done in order to understand how well measurements made on one platform compared to those made on another. Whilst this is easy to do in a controlled laboratory setting, it is more challenging in the real world, and so these comparisons are as valuable as they are rare.
Siddhant Gupta, Greg M. McFarquhar, Joseph R. O'Brien, Michael R. Poellot, David J. Delene, Ian Chang, Lan Gao, Feng Xu, and Jens Redemann
Atmos. Chem. Phys., 22, 12923–12943, https://doi.org/10.5194/acp-22-12923-2022, https://doi.org/10.5194/acp-22-12923-2022, 2022
Short summary
Short summary
The ability of NASA’s Terra and Aqua satellites to retrieve cloud properties and estimate the changes in cloud properties due to aerosol–cloud interactions (ACI) was examined. There was good agreement between satellite retrievals and in situ measurements over the southeast Atlantic Ocean. This suggests that, combined with information on aerosol properties, satellite retrievals of cloud properties can be used to study ACI over larger domains and longer timescales in the absence of in situ data.
Zhipeng Qu, Alexei Korolev, Jason A. Milbrandt, Ivan Heckman, Yongjie Huang, Greg M. McFarquhar, Hugh Morrison, Mengistu Wolde, and Cuong Nguyen
Atmos. Chem. Phys., 22, 12287–12310, https://doi.org/10.5194/acp-22-12287-2022, https://doi.org/10.5194/acp-22-12287-2022, 2022
Short summary
Short summary
Secondary ice production (SIP) is an important physical phenomenon that results in an increase in the cloud ice particle concentration and can have a significant impact on the evolution of clouds. Here, idealized simulations of a tropical convective system were conducted. Agreement between the simulations and observations highlights the impacts of SIP on the maintenance of tropical convection in nature and the importance of including the modelling of SIP in numerical weather prediction models.
Jerome D. Fast, David M. Bell, Gourihar Kulkarni, Jiumeng Liu, Fan Mei, Georges Saliba, John E. Shilling, Kaitlyn Suski, Jason Tomlinson, Jian Wang, Rahul Zaveri, and Alla Zelenyuk
Atmos. Chem. Phys., 22, 11217–11238, https://doi.org/10.5194/acp-22-11217-2022, https://doi.org/10.5194/acp-22-11217-2022, 2022
Short summary
Short summary
Recent aircraft measurements from the HI-SCALE campaign conducted over the Southern Great Plains (SGP) site in Oklahoma are used to quantify spatial variability of aerosol properties in terms of grid spacings typically used by weather and climate models. Surprisingly large horizontal gradients in aerosol properties were frequently observed in this rural area. This spatial variability can be used as an uncertainty range when comparing surface point measurements with model predictions.
Samuel E. LeBlanc, Michal Segal-Rozenhaimer, Jens Redemann, Connor Flynn, Roy R. Johnson, Stephen E. Dunagan, Robert Dahlgren, Jhoon Kim, Myungje Choi, Arlindo da Silva, Patricia Castellanos, Qian Tan, Luke Ziemba, Kenneth Lee Thornhill, and Meloë Kacenelenbogen
Atmos. Chem. Phys., 22, 11275–11304, https://doi.org/10.5194/acp-22-11275-2022, https://doi.org/10.5194/acp-22-11275-2022, 2022
Short summary
Short summary
Airborne observations of atmospheric particles and pollution over Korea during a field campaign in May–June 2016 showed that the smallest atmospheric particles are present in the lowest 2 km of the atmosphere. The aerosol size is more spatially variable than optical thickness. We show this with remote sensing (4STAR), in situ (LARGE) observations, satellite measurements (GOCI), and modeled properties (MERRA-2), and it is contrary to the current understanding.
Haochi Che, Michal Segal-Rozenhaimer, Lu Zhang, Caroline Dang, Paquita Zuidema, Arthur J. Sedlacek III, Xiaoye Zhang, and Connor Flynn
Atmos. Chem. Phys., 22, 8767–8785, https://doi.org/10.5194/acp-22-8767-2022, https://doi.org/10.5194/acp-22-8767-2022, 2022
Short summary
Short summary
A 17-month in situ study on Ascension Island found low single-scattering albedo and strong absorption enhancement of the marine boundary layer aerosols during biomass burnings on the African continent, along with apparent patterns of regular monthly variability. We further discuss the characteristics and drivers behind these changes and find that biomass burning conditions in Africa may be the main factor influencing the optical properties of marine boundary aerosols.
Dongwei Fu, Larry Di Girolamo, Robert M. Rauber, Greg M. McFarquhar, Stephen W. Nesbitt, Jesse Loveridge, Yulan Hong, Bastiaan van Diedenhoven, Brian Cairns, Mikhail D. Alexandrov, Paul Lawson, Sarah Woods, Simone Tanelli, Sebastian Schmidt, Chris Hostetler, and Amy Jo Scarino
Atmos. Chem. Phys., 22, 8259–8285, https://doi.org/10.5194/acp-22-8259-2022, https://doi.org/10.5194/acp-22-8259-2022, 2022
Short summary
Short summary
Satellite-retrieved cloud microphysics are widely used in climate research because of their central role in water and energy cycles. Here, we provide the first detailed investigation of retrieved cloud drop sizes from in situ and various satellite and airborne remote sensing techniques applied to real cumulus cloud fields. We conclude that the most widely used passive remote sensing method employed in climate research produces high biases of 6–8 µm (60 %–80 %) caused by 3-D radiative effects.
Adrien Guyot, Alain Protat, Simon P. Alexander, Andrew R. Klekociuk, Peter Kuma, and Adrian McDonald
Atmos. Meas. Tech., 15, 3663–3681, https://doi.org/10.5194/amt-15-3663-2022, https://doi.org/10.5194/amt-15-3663-2022, 2022
Short summary
Short summary
Ceilometers are instruments that are widely deployed as part of operational networks. They are usually not able to detect cloud phase. Here, we propose an evaluation of various methods to detect supercooled liquid water with ceilometer observations, using an extensive dataset from Davis, Antarctica. Our results highlight the possibility for ceilometers to detect supercooled liquid water in clouds.
Zhenyi Chen, Robyn Schofield, Melita Keywood, Sam Cleland, Alastair G. Williams, Alan Griffiths, Stephen Wilson, Peter Rayner, and Xiaowen Shu
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-104, https://doi.org/10.5194/acp-2022-104, 2022
Revised manuscript not accepted
Short summary
Short summary
This study studied the marine boundary layer (MBL) process and aerosol properties in the Southern Ocean using miniMPL, ceilometer and sodar. Compared to the gradient method, the Image Edge Detection Algorithm provides more reliable boundary layer height estimations, especially when a convective MBL with stratification existed. The diurnal characteristic of BLH with the veering of the wind vector was also observed. Under the continental sources, the MBL maintained a well-mixed layer of 0.3 km.
Siddhant Gupta, Greg M. McFarquhar, Joseph R. O'Brien, Michael R. Poellot, David J. Delene, Rose M. Miller, and Jennifer D. Small Griswold
Atmos. Chem. Phys., 22, 2769–2793, https://doi.org/10.5194/acp-22-2769-2022, https://doi.org/10.5194/acp-22-2769-2022, 2022
Short summary
Short summary
This study evaluates the impact of biomass burning aerosols on precipitation in marine stratocumulus clouds using observations from the NASA ObseRvations of Aerosols above CLouds and their intEractionS (ORACLES) field campaign over the Southeast Atlantic. Instances of contact and separation between aerosol and cloud layers show polluted clouds have a lower precipitation rate and a lower precipitation susceptibility. This information will help improve cloud representation in Earth system models.
Yuli Liu and Gerald G. Mace
Atmos. Meas. Tech., 15, 927–944, https://doi.org/10.5194/amt-15-927-2022, https://doi.org/10.5194/amt-15-927-2022, 2022
Short summary
Short summary
We propose a suite of Bayesian algorithms for synergistic radar and radiometer retrievals to evaluate the next-generation NASA Cloud, Convection and Precipitation (CCP) observing system. The algorithms address pixel-level retrievals using active-only, passive-only, and synergistic active–passive observations. Novel techniques in developing synergistic algorithms are presented. Quantitative assessments of the CCP observing system's capability in retrieving ice cloud microphysics are provided.
Yongjie Huang, Wei Wu, Greg M. McFarquhar, Ming Xue, Hugh Morrison, Jason Milbrandt, Alexei V. Korolev, Yachao Hu, Zhipeng Qu, Mengistu Wolde, Cuong Nguyen, Alfons Schwarzenboeck, and Ivan Heckman
Atmos. Chem. Phys., 22, 2365–2384, https://doi.org/10.5194/acp-22-2365-2022, https://doi.org/10.5194/acp-22-2365-2022, 2022
Short summary
Short summary
Numerous small ice crystals in tropical convective storms are difficult to detect and could be potentially hazardous for commercial aircraft. Previous numerical simulations failed to reproduce this phenomenon and hypothesized that key microphysical processes are still lacking in current models to realistically simulate the phenomenon. This study uses numerical experiments to confirm the dominant role of secondary ice production in the formation of these large numbers of small ice crystals.
Sonya L. Fiddes, Matthew T. Woodhouse, Steve Utembe, Robyn Schofield, Simon P. Alexander, Joel Alroe, Scott D. Chambers, Zhenyi Chen, Luke Cravigan, Erin Dunne, Ruhi S. Humphries, Graham Johnson, Melita D. Keywood, Todd P. Lane, Branka Miljevic, Yuko Omori, Alain Protat, Zoran Ristovski, Paul Selleck, Hilton B. Swan, Hiroshi Tanimoto, Jason P. Ward, and Alastair G. Williams
Atmos. Chem. Phys., 22, 2419–2445, https://doi.org/10.5194/acp-22-2419-2022, https://doi.org/10.5194/acp-22-2419-2022, 2022
Short summary
Short summary
Coral reefs have been found to produce the climatically relevant chemical compound dimethyl sulfide (DMS). It has been suggested that corals can modify their environment via the production of DMS. We use an atmospheric chemistry model to test this theory at a regional scale for the first time. We find that it is unlikely that coral-reef-derived DMS has an influence over local climate, in part due to the proximity to terrestrial and anthropogenic aerosol sources.
Alain Protat, Valentin Louf, Joshua Soderholm, Jordan Brook, and William Ponsonby
Atmos. Meas. Tech., 15, 915–926, https://doi.org/10.5194/amt-15-915-2022, https://doi.org/10.5194/amt-15-915-2022, 2022
Short summary
Short summary
This study uses collocated ship-based, ground-based, and spaceborne radar observations to validate the concept of using the GPM spaceborne radar observations to calibrate national weather radar networks to the accuracy required for operational severe weather applications such as rainfall and hail nowcasting.
Matthew W. Christensen, Andrew Gettelman, Jan Cermak, Guy Dagan, Michael Diamond, Alyson Douglas, Graham Feingold, Franziska Glassmeier, Tom Goren, Daniel P. Grosvenor, Edward Gryspeerdt, Ralph Kahn, Zhanqing Li, Po-Lun Ma, Florent Malavelle, Isabel L. McCoy, Daniel T. McCoy, Greg McFarquhar, Johannes Mülmenstädt, Sandip Pal, Anna Possner, Adam Povey, Johannes Quaas, Daniel Rosenfeld, Anja Schmidt, Roland Schrödner, Armin Sorooshian, Philip Stier, Velle Toll, Duncan Watson-Parris, Robert Wood, Mingxi Yang, and Tianle Yuan
Atmos. Chem. Phys., 22, 641–674, https://doi.org/10.5194/acp-22-641-2022, https://doi.org/10.5194/acp-22-641-2022, 2022
Short summary
Short summary
Trace gases and aerosols (tiny airborne particles) are released from a variety of point sources around the globe. Examples include volcanoes, industrial chimneys, forest fires, and ship stacks. These sources provide opportunistic experiments with which to quantify the role of aerosols in modifying cloud properties. We review the current state of understanding on the influence of aerosol on climate built from the wide range of natural and anthropogenic laboratories investigated in recent decades.
Sabrina P. Cochrane, K. Sebastian Schmidt, Hong Chen, Peter Pilewskie, Scott Kittelman, Jens Redemann, Samuel LeBlanc, Kristina Pistone, Michal Segal Rozenhaimer, Meloë Kacenelenbogen, Yohei Shinozuka, Connor Flynn, Rich Ferrare, Sharon Burton, Chris Hostetler, Marc Mallet, and Paquita Zuidema
Atmos. Meas. Tech., 15, 61–77, https://doi.org/10.5194/amt-15-61-2022, https://doi.org/10.5194/amt-15-61-2022, 2022
Short summary
Short summary
This work presents heating rates derived from aircraft observations from the 2016 and 2017 field campaigns of ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS). We separate the total heating rates into aerosol and gas (primarily water vapor) absorption and explore some of the co-variability of heating rate profiles and their primary drivers, leading to the development of a new concept: the heating rate efficiency (HRE; the heating rate per unit aerosol extinction).
Clémence Rose, Martine Collaud Coen, Elisabeth Andrews, Yong Lin, Isaline Bossert, Cathrine Lund Myhre, Thomas Tuch, Alfred Wiedensohler, Markus Fiebig, Pasi Aalto, Andrés Alastuey, Elisabeth Alonso-Blanco, Marcos Andrade, Begoña Artíñano, Todor Arsov, Urs Baltensperger, Susanne Bastian, Olaf Bath, Johan Paul Beukes, Benjamin T. Brem, Nicolas Bukowiecki, Juan Andrés Casquero-Vera, Sébastien Conil, Konstantinos Eleftheriadis, Olivier Favez, Harald Flentje, Maria I. Gini, Francisco Javier Gómez-Moreno, Martin Gysel-Beer, Anna Gannet Hallar, Ivo Kalapov, Nikos Kalivitis, Anne Kasper-Giebl, Melita Keywood, Jeong Eun Kim, Sang-Woo Kim, Adam Kristensson, Markku Kulmala, Heikki Lihavainen, Neng-Huei Lin, Hassan Lyamani, Angela Marinoni, Sebastiao Martins Dos Santos, Olga L. Mayol-Bracero, Frank Meinhardt, Maik Merkel, Jean-Marc Metzger, Nikolaos Mihalopoulos, Jakub Ondracek, Marco Pandolfi, Noemi Pérez, Tuukka Petäjä, Jean-Eudes Petit, David Picard, Jean-Marc Pichon, Veronique Pont, Jean-Philippe Putaud, Fabienne Reisen, Karine Sellegri, Sangeeta Sharma, Gerhard Schauer, Patrick Sheridan, James Patrick Sherman, Andreas Schwerin, Ralf Sohmer, Mar Sorribas, Junying Sun, Pierre Tulet, Ville Vakkari, Pieter Gideon van Zyl, Fernando Velarde, Paolo Villani, Stergios Vratolis, Zdenek Wagner, Sheng-Hsiang Wang, Kay Weinhold, Rolf Weller, Margarita Yela, Vladimir Zdimal, and Paolo Laj
Atmos. Chem. Phys., 21, 17185–17223, https://doi.org/10.5194/acp-21-17185-2021, https://doi.org/10.5194/acp-21-17185-2021, 2021
Short summary
Short summary
Aerosol particles are a complex component of the atmospheric system the effects of which are among the most uncertain in climate change projections. Using data collected at 62 stations, this study provides the most up-to-date picture of the spatial distribution of particle number concentration and size distribution worldwide, with the aim of contributing to better representation of aerosols and their interactions with clouds in models and, therefore, better evaluation of their impact on climate.
Kamil Mroz, Alessandro Battaglia, Cuong Nguyen, Andrew Heymsfield, Alain Protat, and Mengistu Wolde
Atmos. Meas. Tech., 14, 7243–7254, https://doi.org/10.5194/amt-14-7243-2021, https://doi.org/10.5194/amt-14-7243-2021, 2021
Short summary
Short summary
A method for estimating microphysical properties of ice clouds based on radar measurements is presented. The algorithm exploits the information provided by differences in the radar response at different frequency bands in relation to changes in the snow morphology. The inversion scheme is based on a statistical relation between the radar simulations and the properties of snow calculated from in-cloud sampling.
Rose M. Miller, Greg M. McFarquhar, Robert M. Rauber, Joseph R. O'Brien, Siddhant Gupta, Michal Segal-Rozenhaimer, Amie N. Dobracki, Arthur J. Sedlacek, Sharon P. Burton, Steven G. Howell, Steffen Freitag, and Caroline Dang
Atmos. Chem. Phys., 21, 14815–14831, https://doi.org/10.5194/acp-21-14815-2021, https://doi.org/10.5194/acp-21-14815-2021, 2021
Short summary
Short summary
A large stratocumulus cloud deck resides off the west coast of central Africa. Biomass burning in Africa produces a large plume of aerosol that is carried by the wind over this stratocumulus cloud deck. This paper shows that particles with sizes from 0.01 to 1 mm reside within this plume. Past studies have shown that biomass burning produces such particles, but this is the first study to show that they can be transported westward, over long distances, to the Atlantic stratocumulus cloud deck.
Konstantin Baibakov, Samuel LeBlanc, Keyvan Ranjbar, Norman T. O'Neill, Mengistu Wolde, Jens Redemann, Kristina Pistone, Shao-Meng Li, John Liggio, Katherine Hayden, Tak W. Chan, Michael J. Wheeler, Leonid Nichman, Connor Flynn, and Roy Johnson
Atmos. Chem. Phys., 21, 10671–10687, https://doi.org/10.5194/acp-21-10671-2021, https://doi.org/10.5194/acp-21-10671-2021, 2021
Short summary
Short summary
We find that the airborne measurements of the vertical extinction due to aerosols (aerosol optical depth, AOD) obtained in the Athabasca Oil Sands Region (AOSR) can significantly exceed ground-based values. This can have an effect on estimating the AOSR radiative impact and is relevant to satellite validation based on ground-based measurements. We also show that the AOD can marginally increase as the plumes are being transported away from the source and the new particles are being formed.
Stefanie Kremser, Mike Harvey, Peter Kuma, Sean Hartery, Alexia Saint-Macary, John McGregor, Alex Schuddeboom, Marc von Hobe, Sinikka T. Lennartz, Alex Geddes, Richard Querel, Adrian McDonald, Maija Peltola, Karine Sellegri, Israel Silber, Cliff S. Law, Connor J. Flynn, Andrew Marriner, Thomas C. J. Hill, Paul J. DeMott, Carson C. Hume, Graeme Plank, Geoffrey Graham, and Simon Parsons
Earth Syst. Sci. Data, 13, 3115–3153, https://doi.org/10.5194/essd-13-3115-2021, https://doi.org/10.5194/essd-13-3115-2021, 2021
Short summary
Short summary
Aerosol–cloud interactions over the Southern Ocean are poorly understood and remain a major source of uncertainty in climate models. This study presents ship-borne measurements, collected during a 6-week voyage into the Southern Ocean in 2018, that are an important supplement to satellite-based measurements. For example, these measurements include data on low-level clouds and aerosol composition in the marine boundary layer, which can be used in climate model evaluation efforts.
Cited articles
Alexander, S. P. and Protat, A.: Vertical Profiling of Aerosols With a
Combined Raman-Elastic Backscatter Lidar in the Remote Southern
Ocean Marine Boundary Layer (43–66∘S,
132–150∘E), J. Geophys. Res.-Atmos., 124, 12107–12125, https://doi.org/10.1029/2019JD030628, 2019. a
Alroe, J., Cravigan, L. T., Miljevic, B., Johnson, G. R., Selleck, P., Humphries, R. S., Keywood, M. D., Chambers, S. D., Williams, A. G., and Ristovski, Z. D.: Marine productivity and synoptic meteorology drive summer-time variability in Southern Ocean aerosols, Atmos. Chem. Phys., 20, 8047–8062, https://doi.org/10.5194/acp-20-8047-2020, 2020. a, b, c, d, e, f, g
Andreae, M. O.: Correlation between cloud condensation nuclei concentration and aerosol optical thickness in remote and polluted regions, Atmos. Chem. Phys., 9, 543–556, https://doi.org/10.5194/acp-9-543-2009, 2009. a
Asmi, E., Frey, A., Virkkula, A., Ehn, M., Manninen, H. E., Timonen, H., Tolonen-Kivimäki, O., Aurela, M., Hillamo, R., and Kulmala, M.: Hygroscopicity and chemical composition of Antarctic sub-micrometre aerosol particles and observations of new particle formation, Atmos. Chem. Phys., 10, 4253–4271, https://doi.org/10.5194/acp-10-4253-2010, 2010. a
Ayers, G. P. and Cainey, J. M.: The CLAW Hypothesis: A Review of the
Major Developments, Environ. Chem., 4, 366–374, 2007. a
Ayers, G. P. and Gras, J. L.: Seasonal Relationship between Cloud Condensation
Nuclei and Aerosol Methanesulphonate in Marine Air, Nature, 353, 834–835,
https://doi.org/10.1038/353834a0, 1991. a
Ayers, G. P., Ivey, J. P., and Gillett, R. W.: Coherence between Seasonal
Cycles of Dimethyl Sulphide, Methanesulphonate and Sulphate in Marine Air,
Nature, 349, 404–406, https://doi.org/10.1038/349404a0, 1991. a
Ayers, G. P., Cainey, J. M., Gillett, R. W., Saltzman, E. S., and Hooper, M.:
Sulfur Dioxide and Dimethyl Sulphide in Marine Air at Cape Grim,
Tasmania, Tellus B, 49, 292–299, https://doi.org/10.3402/tellusb.v49i3.15968, 1997. a
Bates, T. S., Huebert, B. J., Gras, J. L., Griffiths, F. B., and Durkee, P. A.:
International Global Atmospheric Chemistry (IGAC) Project's
First Aerosol Characterization Experiment (ACE 1): Overview,
J. Geophys. Res., 103, 16297–16297,
https://doi.org/10.1029/97JD03741, 1998. a, b
Bigg, E. K.: Aerosol over the Southern Ocean, Atmos. Res., 25,
583–600, https://doi.org/10.1016/0169-8095(90)90039-F, 1990. a
Boers, R.: Influence of Seasonal Variation in Cloud Condensation Nuclei,
Drizzle, and Solar Radiation, on Marine Stratocumulus Optical Depth, Tellus,
47B, 578–586, https://doi.org/10.3402/tellusb.v47i5.16073, 1995. a
Brock, C. A., Williamson, C., Kupc, A., Froyd, K. D., Erdesz, F., Wagner, N., Richardson, M., Schwarz, J. P., Gao, R.-S., Katich, J. M., Campuzano-Jost, P., Nault, B. A., Schroder, J. C., Jimenez, J. L., Weinzierl, B., Dollner, M., Bui, T., and Murphy, D. M.: Aerosol size distributions during the Atmospheric Tomography Mission (ATom): methods, uncertainties, and data products, Atmos. Meas. Tech., 12, 3081–3099, https://doi.org/10.5194/amt-12-3081-2019, 2019. a
Carslaw, K. S., Lee, L. A., Reddington, C. L., Pringle, K. J., Rap, A.,
Forster, P. M., Mann, G. W., Spracklen, D. V., Woodhouse, M. T., Regayre,
L. A., and Pierce, J. R.: Large Contribution of Natural Aerosols to
Uncertainty in Indirect Forcing, Nature, 503, 67–71,
https://doi.org/10.1038/nature12674, 2013. a
Covert, D. S., Gras, J. L., Wiedensohler, A., and Stratmann, F.: Comparison of
Directly Measured CCN with CCN Modeled from the Number-Size
Distribution in the Marine Boundary Layer during ACE 1 at Cape Grim,
Tasmania, J. Geophys. Res.-Atmos., 103,
16597–16608, https://doi.org/10.1029/98JD01093, 1998. a
Dall'Osto, M., Ovadnevaite, J., Paglione, M., Beddows, D. C. S., Ceburnis, D.,
Cree, C., Cortés, P., Zamanillo, M., Nunes, S. O., Pérez, G. L.,
Ortega-Retuerta, E., Emelianov, M., Vaqué, D., Marrasé, C.,
Estrada, M., Sala, M. M., Vidal, M., Fitzsimons, M. F., Beale, R., Airs, R.,
Rinaldi, M., Decesari, S., Cristina Facchini, M., Harrison, R. M., O'Dowd,
C., and Simó, R.: Antarctic Sea Ice Region as a Source of Biogenic
Organic Nitrogen in Aerosols, Sci. Rep., 7, 6047–6047,
https://doi.org/10.1038/s41598-017-06188-x, 2017. a
Davison, B., Hewitt, C. N., O'Dowd, C. D., Lowe, J. A., Smith, M. H.,
Schwikowski, M., Baltensperger, U., and Harrison, R. M.: Dimethyl Sulfide,
Methane Sulfonic Acid and Physicochemical Aerosol Properties in Atlantic
Air from the United Kingdom to Halley Bay, J. Geophys.
Res., 101, 22855–22867, https://doi.org/10.1029/96jd01166, 1996. a
Deppeler, S. L. and Davidson, A. T.: Southern Ocean Phytoplankton in a
Changing Climate, Front. Mar. Sci., 4, 40,
https://doi.org/10.3389/fmars.2017.00040, 2017. a
Draxler, R. R. and Hess, G. D.: An Overview of the HYSPLIT_4
Modelling System for Trajectories, Dispersion, and
Deposition, Aust. Meteorol. Mag., 47, 295–308, 1998. a
ECMWF: ERA5 Hourly Data on Single Levels from 1979 to Present, Copernicus Climate Data Store [data set],
https://doi.org/10.24381/cds.adbb2d47, 2018. a
Marine National Facility: RV Investigator Voyage IN2018_V01 Underway UWY Data, available at:
https://marlin.csiro.au/geonetwork/srv/eng/catalog.search;jsessionid=13htmz0h4h8wcjui4ojzvg3sy#/metadata/eb348f53-514c-4edd-9e54-61bbcb86ed83 (last access: 3 October 2020),
2018. a
Fossum, K. N., Ovadnevaite, J., Ceburnis, D., Dall'Osto, M., Marullo, S.,
Bellacicco, M., Simó, R., Liu, D., Flynn, M., Zuend, A., and O'Dowd, C.:
Summertime Primary and Secondary Contributions to Southern Ocean
Cloud Condensation Nuclei, Sci. Rep., 8, 13844,
https://doi.org/10.1038/s41598-018-32047-4, 2018. a, b, c, d, e, f
Fossum, K. N., Ovadnevaite, J., Ceburnis, D., Preißler, J., Snider, J. R.,
Huang, R.-J., Zuend, A., and O'Dowd, C.: Sea-Spray Regulates Sulfate Cloud
Droplet Activation over Oceans, Clim. Atmos. Sci., 3, 1–6,
https://doi.org/10.1038/s41612-020-0116-2, 2020. a
Frey, W. R. and Kay, J. E.: The Influence of Extratropical Cloud Phase and
Amount Feedbacks on Climate Sensitivity, Clim. Dynam., 50, 3097–3116,
https://doi.org/10.1007/s00382-017-3796-5, 2018. a
Fröhlich, R., Cubison, M. J., Slowik, J. G., Bukowiecki, N., Prévôt, A. S. H., Baltensperger, U., Schneider, J., Kimmel, J. R., Gonin, M., Rohner, U., Worsnop, D. R., and Jayne, J. T.: The ToF-ACSM: a portable aerosol chemical speciation monitor with TOFMS detection, Atmos. Meas. Tech., 6, 3225–3241, https://doi.org/10.5194/amt-6-3225-2013, 2013. a
Frossard, A. A., Russell, L. M., Burrows, S. M., Elliott, S. M., Bates, T. S.,
and Quinn, P. K.: Sources and Composition of Submicron Organic Mass in Marine
Aerosol Particles, J. Geophys. Res.-Atmos., 119,
12977–13003, https://doi.org/10.1002/2014JD021913, 2014. a
Gettelman, A., Lin, L., Medeiros, B., and Olson, J.: Climate Feedback
Variance and the Interaction of Aerosol Forcing and Feedbacks,
J. Climate, 29, 6659–6675, https://doi.org/10.1175/JCLI-D-16-0151.1, 2016. a
Gras, J. L.: Cloud Condensation Nuclei over the Southern Ocean, Geophys.
Res. Lett., 17, 1565–1567, https://doi.org/10.1029/GL017i010p01565, 1990. a, b
Gras, J. L. and Keywood, M.: Cloud condensation nuclei over the Southern Ocean: wind dependence and seasonal cycles, Atmos. Chem. Phys., 17, 4419–4432, https://doi.org/10.5194/acp-17-4419-2017, 2017. a, b, c, d
Hansen, G., Aspmo, K., Berg, T., Edvardsen, K., Fiebig, M., Kallenborn, R.,
Krognes, T., Lunder, C., Stebel, K., Schmidbauer, N., Solberg, S., and Yttri,
K. E.: Atmospheric Monitoring at the Norwegian Antarctic Station
Troll: Measurement Programme and First Results, Polar Res., 28,
353–363, https://doi.org/10.3402/polar.v28i3.6142, 2009. a
Hara, K., Osada, K., Nishita-Hara, C., and Yamanouchi, T.: Seasonal variations and vertical features of aerosol particles in the Antarctic troposphere, Atmos. Chem. Phys., 11, 5471–5484, https://doi.org/10.5194/acp-11-5471-2011, 2011. a
Hara, K., Osada, K., Yabuki, M., Matoba, S., Hirabayashi, M., Fujita, S.,
Nakazawa, F., and Yamanouchi, T.: Atmospheric Sea-Salt and Halogen Cycles in
the Antarctic, Environ. Sci. Processes Impacts, 22, 2003–2022,
https://doi.org/10.1039/D0EM00092B, 2020. a
Humphries, R. S., Schofield, R., Keywood, M. D., Ward, J., Pierce, J. R., Gionfriddo, C. M., Tate, M. T., Krabbenhoft, D. P., Galbally, I. E., Molloy, S. B., Klekociuk, A. R., Johnston, P. V., Kreher, K., Thomas, A. J., Robinson, A. D., Harris, N. R. P., Johnson, R., and Wilson, S. R.: Boundary layer new particle formation over East Antarctic sea ice – possible Hg-driven nucleation?, Atmos. Chem. Phys., 15, 13339–13364, https://doi.org/10.5194/acp-15-13339-2015, 2015. a
Humphries, R. S., McRobert, I. M., Ponsonby, W. A., Ward, J. P., Keywood, M. D., Loh, Z. M., Krummel, P. B., and Harnwell, J.: Identification of platform exhaust on the RV Investigator, Atmos. Meas. Tech., 12, 3019–3038, https://doi.org/10.5194/amt-12-3019-2019, 2019. a, b
Humphries, R. S., Ward, J., McRobert, I., Thomas, S., Harnwell, J., Marouchos,
A., Keywood, M., Molloy, S. B., Loh, Z. M., Krummel, P. B., Ponsonby, W., and
Crawford, H.: RV Investigator – the World's First Mobile GAW
Station, in preparation, 2021b. a
IPCC: Clouds and Aerosols, in: Climate Change 2013
– The Physical Science Basis: Working Group I
Contribution to the Fifth Assessment Report of the Intergovernmental
Panel on Climate Change, Cambridge University Press,
Cambridge, 571–658, https://doi.org/10.1017/CBO9781107415324.016, 2014. a
Ito, T.: Size Distribution of Antarctic Submicron Aerosols, Tellus
B, 45B, 145–159, 1993. a
Järvinen, E., Virkkula, A., Nieminen, T., Aalto, P. P., Asmi, E., Lanconelli, C., Busetto, M., Lupi, A., Schioppo, R., Vitale, V., Mazzola, M., Petäjä, T., Kerminen, V.-M., and Kulmala, M.: Seasonal cycle and modal structure of particle number size distribution at Dome C, Antarctica, Atmos. Chem. Phys., 13, 7473–7487, https://doi.org/10.5194/acp-13-7473-2013, 2013. a
Kanamitsu, M.: Description of the NMC Global Data Assimilation and
Forecast System, Weather Forecast., 4, 335–342,
https://doi.org/10.1175/1520-0434(1989)004<0335:DOTNGD>2.0.CO;2, 1989. a
Koponen, I. K., Virkkula, A., Hillamo, R., Kerminen, V.-M., and Kulmala, M.:
Number Size Distributions and Concentrations of the Continental Summer
Aerosols in Queen Maud Land, Antarctica, J. Geophys.
Res.-Atmos., 108, 4587–4587, https://doi.org/10.1029/2003jd003614, 2003. a
Kuang, C., Salwen, C., Boyer, M., and Singh, A.: Atmospheric Radiation
Measurement (ARM) User Facility, 2017, Updated Hourly, Condensation
Particle Counter (AOSCPCF), 2017-10-29 to 2018-03-26, ARM Mobile
Facility (MAR) Hobart, AUS to Antarctic Coast – Resupply
Ship Aurora Australis, AMF2 (M1) [data set], https://doi.org/10.5439/1046184, 2018. a, b
Kulkarni, G. R., Flynn, C., and Koontz, A.: Atmospheric Radiation
Measurement (ARM) User Facility, 2017, Updated Hourly, Cloud
Condensation Nuclei Particle Counter (AOSCCN100), 2017-10-29 to
2018-03-24, ARM Mobile Facility (MAR) Hobart, AUS to
Antarctic Coast – Resupply Ship Aurora Australis, AMF2 (M1) [data set], https://doi.org/10.5439/1227964,
2018. a, b
Labuschagne, C., Kuyper, B., Brunke, E.-G., Mokolo, T., van der Spuy, D.,
Martin, L., Mbambalala, E., Parker, B., Khan, M. A. H., Davies-Coleman,
M. T., Shallcross, D. E., and Joubert, W.: A Review of Four Decades of
Atmospheric Trace Gas Measurements at Cape Point, South Africa,
T. Roy. Soc. S. Afr., 73, 113–132,
https://doi.org/10.1080/0035919X.2018.1477854, 2018. a
Lana, A., Bell, T. G., Simó, R., Vallina, S. M., Ballabrera-Poy, J.,
Kettle, A. J., Dachs, J., Bopp, L., Saltzman, E. S., Stefels, J., Johnson,
J. E., and Liss, P. S.: An Updated Climatology of Surface Dimethlysulfide
Concentrations and Emission Fluxes in the Global Ocean, Global Biogeochem.
Cy., 25, GB1004–GB1004, https://doi.org/10.1029/2010gb003850, 2011. a
Law, C. S., Smith, M. J., Harvey, M. J., Bell, T. G., Cravigan, L. T., Elliott, F. C., Lawson, S. J., Lizotte, M., Marriner, A., McGregor, J., Ristovski, Z., Safi, K. A., Saltzman, E. S., Vaattovaara, P., and Walker, C. F.: Overview and preliminary results of the Surface Ocean Aerosol Production (SOAP) campaign, Atmos. Chem. Phys., 17, 13645–13667, https://doi.org/10.5194/acp-17-13645-2017, 2017. a
Liu, P. S. K., Deng, R., Smith, K. A., Williams, L. R., Jayne, J. T.,
Canagaratna, M. R., Moore, K., Onasch, T. B., Worsnop, D. R., and Deshler,
T.: Transmission Efficiency of an Aerodynamic Focusing Lens System:
Comparison of Model Calculations and Laboratory Measurements for
the Aerodyne Aerosol Mass Spectrometer, Aerosol Sci. Technol.,
41, 721–733, https://doi.org/10.1080/02786820701422278, 2007. a
Mace, G. G. and Protat, A.: Clouds over the Southern Ocean as Observed
from the R/V Investigator during CAPRICORN. Part I: Cloud
Occurrence and Phase Partitioning, J. Applied Meteorol.
Clim., 57, 1783–1803, https://doi.org/10.1175/JAMC-D-17-0194.1, 2018. a
Mace, G. G., Protat, A., Humphries, R. S., Alexander, S. P., McRobert, I. M.,
Ward, J., Selleck, P., Keywood, M., and McFarquhar, G. M.: Southern Ocean
Cloud Properties Derived From CAPRICORN and MARCUS Data, J.
Geophys. Res.-Atmos., 126, e2020JD033368,
https://doi.org/10.1029/2020JD033368, 2021. a, b, c, d
Marchand, R., Wood, R., Bretherton, C., McFarquhar, G., Protat, A., Quinn, P.,
Siems, S., Jakob, C., Alexander, S., and Weller, B.: Southern Ocean
Clouds, Radiation, Aerosol Transport Experimental Study – White
Paper, available at: https://atmos.uw.edu/~roj/nobackup/Southern_Ocean_Workshop_2014/Southern_Ocean_Workshop_2014_White_Paper.pdf (last access: 18 August 2021), 2014. a
McCoy, I. L., McCoy, D. T., Wood, R., Regayre, L., Watson-Parris, D.,
Grosvenor, D. P., Mulcahy, J. P., Hu, Y., Bender, F. A.-M., Field, P. R.,
Carslaw, K. S., and Gordon, H.: The Hemispheric Contrast in Cloud
Microphysical Properties Constrains Aerosol Forcing, P.
Natl. Acad. Sci. USA, 117, 18998–19006, https://doi.org/10.1073/pnas.1922502117, 2020. a
McFarquhar, G. M., Bretherton, C. S., Marchand, R., Protat, A., DeMott, P. J.,
Alexander, S. P., Roberts, G. C., Twohy, C. H., Toohey, D., Siems, S., Huang,
Y., Wood, R., Rauber, R. M., Lasher-Trapp, S., Jensen, J., Stith, J. L.,
Mace, J., Um, J., Järvinen, E., Schnaiter, M., Gettelman, A., Sanchez,
K. J., McCluskey, C. S., Russell, L. M., McCoy, I. L., Atlas, R. L., Bardeen,
C. G., Moore, K. A., Hill, T. C. J., Humphries, R. S., Keywood, M. D.,
Ristovski, Z., Cravigan, L., Schofield, R., Fairall, C., Mallet, M. D.,
Kreidenweis, S. M., Rainwater, B., D'Alessandro, J., Wang, Y., Wu, W.,
Saliba, G., Levin, E. J. T., Ding, S., Lang, F., Truong, S. C. H., Wolff, C.,
Haggerty, J., Harvey, M. J., Klekociuk, A. R., and McDonald, A.: Observations
of Clouds, Aerosols, Precipitation, and Surface Radiation
over the Southern Ocean: An Overview of CAPRICORN, MARCUS,
MICRE, and SOCRATES, B. Am. Meteorol. Soc. USA,
102, E894–E928, https://doi.org/10.1175/BAMS-D-20-0132.1, 2021. a, b
O'Dowd, C. D., Lowe, J. A., Smith, M. H., Davison, B., Hewitt, C. N., and
Harrison, R. M.: Biogenic Sulphur Emissions and Inferred
Non-Sea-Salt-Sulphate Cloud Condensation Nuclei in and around Antarctica,
J. Geophys. Res.-Atmos., 102, 12839–12854,
https://doi.org/10.1029/96jd02749, 1997. a
Pant, V., Siingh, D., and Kamra, A. K.: Size Distribution of Atmospheric
Aerosols at Maitri, Antarctica, Atmos. Environ., 45,
5138–5149, https://doi.org/10.1016/j.atmosenv.2011.06.028, 2011. a
Pierce, J. R. and Adams, P. J.: Uncertainty in global CCN concentrations from uncertain aerosol nucleation and primary emission rates, Atmos. Chem. Phys., 9, 1339–1356, https://doi.org/10.5194/acp-9-1339-2009, 2009. a
Protat, A., Schulz, E., Rikus, L., Sun, Z., Xiao, Y., and Keywood, M.:
Shipborne Observations of the Radiative Effect of Southern Ocean Clouds,
J. Geophys. Res.-Atmos., 122, 318–328,
https://doi.org/10.1002/2016JD026061, 2017. a
Quinn, P. K., Bates, T. S., Coffman, D. J., Miller, T. L., Johnson, J. E.,
Covert, D. S., Putaud, J.-P., Neusüß, C., and Novakov, T.: A
Comparison of Aerosol Chemical and Optical Properties from the 1st and 2nd
Aerosol Characterization Experiments, Tellus B, 52, 239–257,
https://doi.org/10.3402/tellusb.v52i2.16103, 2000. a
Rinaldi, M., Decesari, S., Finessi, E., Giulianelli, L., Carbone, C., Fuzzi,
S., O'Dowd, C. D., Ceburnis, D., and Facchini, M. C.: Primary and Secondary
Organic Marine Aerosol and Oceanic Biological Activity: Recent
Results and New Perspectives for Future Studies, Adv.
Meteorol., 2010, e310682, https://doi.org/10.1155/2010/310682, 2010. a
Rinaldi, M., Paglione, M., Decesari, S., Harrison, R. M., Beddows, D. C.,
Ovadnevaite, J., Ceburnis, D., O'Dowd, C. D., Simó, R., and Dall'Osto,
M.: Contribution of Water-Soluble Organic Matter from Multiple
Marine Geographic Eco-Regions to Aerosols around Antarctica,
Environ. Sci. Technol., 54, 7807–7817,
https://doi.org/10.1021/acs.est.0c00695, 2020. a
Samson, J. A., Barnard, S. C., Obremski, J. S., Riley, D. C., Black, J. J., and
Hogan, A. W.: On the Systematic Variation in Surface Aerosol Concentration at
the South Pole, Atmos. Res., 25, 385–396,
https://doi.org/10.1016/0169-8095(90)90023-6, 1990. a
Sanchez, K. J., Chen, C.-L., Russell, L. M., Betha, R., Liu, J., Price, D. J.,
Massoli, P., Ziemba, L. D., Crosbie, E. C., Moore, R. H., Müller, M.,
Schiller, S. A., Wisthaler, A., Lee, A. K. Y., Quinn, P. K., Bates, T. S.,
Porter, J., Bell, T. G., Saltzman, E. S., Vaillancourt, R. D., and
Behrenfeld, M. J.: Substantial Seasonal Contribution of Observed
Biogenic Sulfate Particles to Cloud Condensation Nuclei, Sci.
Rep., 8, 3235, https://doi.org/10.1038/s41598-018-21590-9, 2018. a
Sanchez, K. J., Roberts, G. C., Saliba, G., Russell, L. M., Twohy, C., Reeves, J. M., Humphries, R. S., Keywood, M. D., Ward, J. P., and McRobert, I. M.: Measurement report: Cloud processes and the transport of biological emissions affect southern ocean particle and cloud condensation nuclei concentrations, Atmos. Chem. Phys., 21, 3427–3446, https://doi.org/10.5194/acp-21-3427-2021, 2021. a, b, c
Sato, K., Inoue, J., Alexander, S. P., McFarquhar, G., and Yamazaki, A.:
Improved Reanalysis and Prediction of Atmospheric Fields Over the
Southern Ocean Using Campaign-Based Radiosonde Observations,
Geophys. Res. Lett., 45, 11406–11413, https://doi.org/10.1029/2018GL079037, 2018. a
Schmale, J., Baccarini, A., Thurnherr, I., Henning, S., Efraim, A., Regayre,
L., Bolas, C., Hartmann, M., Welti, A., Lehtipalo, K., Aemisegger, F.,
Tatzelt, C., Landwehr, S., Modini, R. L., Tummon, F., Johnson, J. S., Harris,
N., Schnaiter, M., Toffoli, A., Derkani, M., Bukowiecki, N., Stratmann, F.,
Dommen, J., Baltensperger, U., Wernli, H., Rosenfeld, D., Gysel-Beer, M.,
and Carslaw, K. S.: Overview of the Antarctic Circumnavigation
Expedition: Study of Preindustrial-like Aerosols and Their
Climate Effects (ACE-SPACE), B. Am.
Meteorol. Soc., 100, 2260–2283, https://doi.org/10.1175/BAMS-D-18-0187.1,
2019. a, b, c, d, e, f, g
Scott, D. W.: Multivariate Density Estimation: Theory, Practice,
and Visualization, 3nd Edn., Wiley Series in
Probability and Statistics, John Wiley & Sons, Inc., 2015. a
Shaw, G. E.: Antarctic Aerosols: A Review, Rev. Geophys., 26,
89–112, https://doi.org/10.1029/RG026i001p00089, 1988. a
Shindell, D. T., Lamarque, J.-F., Schulz, M., Flanner, M., Jiao, C., Chin, M., Young, P. J., Lee, Y. H., Rotstayn, L., Mahowald, N., Milly, G., Faluvegi, G., Balkanski, Y., Collins, W. J., Conley, A. J., Dalsoren, S., Easter, R., Ghan, S., Horowitz, L., Liu, X., Myhre, G., Nagashima, T., Naik, V., Rumbold, S. T., Skeie, R., Sudo, K., Szopa, S., Takemura, T., Voulgarakis, A., Yoon, J.-H., and Lo, F.: Radiative forcing in the ACCMIP historical and future climate simulations, Atmos. Chem. Phys., 13, 2939–2974, https://doi.org/10.5194/acp-13-2939-2013, 2013. a
Simmons, J. B., Humphries, R. S., Wilson, S. R., Chambers, S. D., Williams, A. G., Griffiths, A. D., McRobert, I. M., Ward, J. P., Keywood, M. D., and Gribben, S.: Summer aerosol measurements over the East Antarctic seasonal ice zone, Atmos. Chem. Phys., 21, 9497–9513, https://doi.org/10.5194/acp-21-9497-2021, 2021. a, b, c, d
Stephens, B. B., Long, M. C., Keeling, R. F., Kort, E. A., Sweeney, C., Apel,
E. C., Atlas, E. L., Beaton, S., Bent, J. D., Blake, N. J., Bresch, J. F.,
Casey, J., Daube, B. C., Diao, M., Diaz, E., Dierssen, H., Donets, V., Gao,
B.-C., Gierach, M., Green, R., Haag, J., Hayman, M., Hills, A. J.,
Hoecker-Martínez, M. S., Honomichl, S. B., Hornbrook, R. S., Jensen,
J. B., Li, R.-R., McCubbin, I., McKain, K., Morgan, E. J., Nolte, S., Powers,
J. G., Rainwater, B., Randolph, K., Reeves, M., Schauffler, S. M., Smith, K.,
Smith, M., Stith, J., Stossmeister, G., Toohey, D. W., and Watt, A. S.: The
O2/N2 Ratio and CO2 Airborne Southern Ocean Study, B.
Am. Meteorol. Soc., 99, 381–402,
https://doi.org/10.1175/BAMS-D-16-0206.1, 2018. a
Swietlicki, E., Hansson, H. C., Hämeri, K., Svenningsson, B., Massling, A.,
Mcfiggans, G., Mcmurry, P. H., Petäjä, T., Tunved, P., Gysel, M.,
Topping, D., Weingartner, E., Baltensperger, U., Rissler, J., Wiedensohler,
A., and Kulmala, M.: Hygroscopic Properties of Submicrometer Atmospheric
Aerosol Particles Measured with H-TDMA Instruments in Various
Environments – a Review, Tellus B, 60, 432–469, https://doi.org/10.1111/j.1600-0889.2008.00350.x, 2008. a
Symons, L.: Aurora Australis Voyage 4 2017/18 Track and Underway
Data, Australian Antarctic Data Centre [data set], available at: https://data.aad.gov.au/metadata/records/201718040 (last access: 3 October 2020),
2019a. a
Symons, L.: Aurora Australis Voyage 2 2017/18 Track and Underway
Data Australian Antarctic Data Centre [data set], available at: https://data.aad.gov.au/metadata/records/201718020 (last access: 3 October 2020),
2019b. a
Symons, L.: Aurora Australis Voyage 1 2017/18 Track and Underway
Data, Australian Antarctic Data Centre [data set], available at: https://data.aad.gov.au/metadata/records/201718010 (last access: 3 October 2020),
2019c. a
Symons, L.: Aurora Australis Voyage 3 2017/18 Track and Underway
Data, Australian Antarctic Data Centre [data set], available at: https://data.aad.gov.au/metadata/records/201718030 (last access: 3 October 2020),
2019d.
a
Trenberth, K. E. and Fasullo, J. T.: Simulation of Present-Day and
Twenty-First-Century Energy Budgets of the Southern Oceans,
J. Climate, 23, 440–454, https://doi.org/10.1175/2009JCLI3152.1, 2010. a
Twohy, C. H., DeMott, P. J., Russell, L. M., Toohey, D. W., Rainwater, B.,
Geiss, R., Sanchez, K. J., Lewis, S., Roberts, G. C., Humphries, R. S.,
McCluskey, C. S., Moore, K. A., Selleck, P. W., Keywood, M. D., Ward, J. P.,
and McRobert, I. M.: Cloud-Nucleating Particles Over the Southern
Ocean in a Changing Climate, Earth's Future, 9, e2020EF001673,
https://doi.org/10.1029/2020EF001673, 2021. a, b, c
Vallina, S. M., Simó, R., and Gassó, S.: What Controls CCN
Seasonality in the Southern Ocean? A Statistical Analysis Based on
Satellite-Derived Chlorophyll and CCN and Model-Estimated OH Radical
and Rainfall, Global Biogeochem. Cy., 20, GB1014, https://doi.org/10.1029/2005GB002597,
2006. a
Virkkula, A., Asmi, E., Teinilä, K., Frey, A., Aurela, M., Timonen, H.,
Mäkelä, T., Samuli, A., Hillamo, R., Aalto, P. P., Kirkwood, S., and
Kulmala, M.: Review of Aerosol Research at the Finnish Antarctic
Research Station Aboa and Its Surroundings in Queen Maud Land,
Antarctica, Geophysica, 45, 163–181, 2009. a
Weller, R., Minikin, A., Wagenbach, D., and Dreiling, V.: Characterization of the inter-annual, seasonal, and diurnal variations of condensation particle concentrations at Neumayer, Antarctica, Atmos. Chem. Phys., 11, 13243–13257, https://doi.org/10.5194/acp-11-13243-2011, 2011. a
Wofsy, S. C.: HIAPER Pole-to-Pole Observations (HIPPO):
Fine-Grained, Global-Scale Measurements of Climatically Important Atmospheric
Gases and Aerosols, Philos. T. R. Soc. A, 369, 2073–2086,
https://doi.org/10.1098/rsta.2010.0313, 2011. a
Short summary
The Southern Ocean region is one of the most pristine in the world and serves as an important proxy for the pre-industrial atmosphere. Improving our understanding of the natural processes in this region is likely to result in the largest reductions in the uncertainty of climate and earth system models. In this paper we present a statistical summary of the latitudinal gradient of aerosol and cloud condensation nuclei concentrations obtained from five voyages spanning the Southern Ocean.
The Southern Ocean region is one of the most pristine in the world and serves as an important...
Altmetrics
Final-revised paper
Preprint