Articles | Volume 20, issue 3
Atmos. Chem. Phys., 20, 1565–1590, 2020
https://doi.org/10.5194/acp-20-1565-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue: New observations and related modelling studies of the aerosol–cloud–climate...
Research article 07 Feb 2020
Research article | 07 Feb 2020
Above-cloud aerosol optical depth from airborne observations in the southeast Atlantic
Samuel E. LeBlanc et al.
Related authors
Siddhant Gupta, Greg M. McFarquhar, Joseph R. O'Brien, David J. Delene, Michael R. Poellot, Amie Dobracki, James R. Podolske, Jens Redemann, Samuel E. LeBlanc, Michal Segal-Rozenhaimer, and Kristina Pistone
Atmos. Chem. Phys., 21, 4615–4635, https://doi.org/10.5194/acp-21-4615-2021, https://doi.org/10.5194/acp-21-4615-2021, 2021
Short summary
Short summary
Observations from the 2016 NASA ObseRvations of Aerosols above CLouds and their intEractionS (ORACLES) field campaign examine how biomass burning aerosols from southern Africa affect marine stratocumulus cloud decks over the Southeast Atlantic. Instances of contact and separation between aerosols and clouds are examined to quantify the impact of aerosol mixing into cloud top on cloud drop numbers and sizes. This information is needed for improving Earth system models and satellite retrievals.
Jens Redemann, Robert Wood, Paquita Zuidema, Sarah J. Doherty, Bernadette Luna, Samuel E. LeBlanc, Michael S. Diamond, Yohei Shinozuka, Ian Y. Chang, Rei Ueyama, Leonhard Pfister, Ju-Mee Ryoo, Amie N. Dobracki, Arlindo M. da Silva, Karla M. Longo, Meloë S. Kacenelenbogen, Connor J. Flynn, Kristina Pistone, Nichola M. Knox, Stuart J. Piketh, James M. Haywood, Paola Formenti, Marc Mallet, Philip Stier, Andrew S. Ackerman, Susanne E. Bauer, Ann M. Fridlind, Gregory R. Carmichael, Pablo E. Saide, Gonzalo A. Ferrada, Steven G. Howell, Steffen Freitag, Brian Cairns, Brent N. Holben, Kirk D. Knobelspiesse, Simone Tanelli, Tristan S. L'Ecuyer, Andrew M. Dzambo, Ousmane O. Sy, Greg M. McFarquhar, Michael R. Poellot, Siddhant Gupta, Joseph R. O'Brien, Athanasios Nenes, Mary Kacarab, Jenny P. S. Wong, Jennifer D. Small-Griswold, Kenneth L. Thornhill, David Noone, James R. Podolske, K. Sebastian Schmidt, Peter Pilewskie, Hong Chen, Sabrina P. Cochrane, Arthur J. Sedlacek, Timothy J. Lang, Eric Stith, Michal Segal-Rozenhaimer, Richard A. Ferrare, Sharon P. Burton, Chris A. Hostetler, David J. Diner, Felix C. Seidel, Steven E. Platnick, Jeffrey S. Myers, Kerry G. Meyer, Douglas A. Spangenberg, Hal Maring, and Lan Gao
Atmos. Chem. Phys., 21, 1507–1563, https://doi.org/10.5194/acp-21-1507-2021, https://doi.org/10.5194/acp-21-1507-2021, 2021
Short summary
Short summary
Southern Africa produces significant biomass burning emissions whose impacts on regional and global climate are poorly understood. ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) is a 5-year NASA investigation designed to study the key processes that determine these climate impacts. The main purpose of this paper is to familiarize the broader scientific community with the ORACLES project, the dataset it produced, and the most important initial findings.
Sabrina P. Cochrane, K. Sebastian Schmidt, Hong Chen, Peter Pilewskie, Scott Kittelman, Jens Redemann, Samuel LeBlanc, Kristina Pistone, Meloë Kacenelenbogen, Michal Segal Rozenhaimer, Yohei Shinozuka, Connor Flynn, Amie Dobracki, Paquita Zuidema, Steven Howell, Steffen Freitag, and Sarah Doherty
Atmos. Meas. Tech., 14, 567–593, https://doi.org/10.5194/amt-14-567-2021, https://doi.org/10.5194/amt-14-567-2021, 2021
Short summary
Short summary
Based on observations from the 2016 and 2017 field campaigns of ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS), this work establishes an observationally driven link from mid-visible aerosol optical depth (AOD) and other scene parameters to broadband shortwave irradiance (and by extension the direct aerosol radiative effect, DARE). The majority of the case-to-case DARE variability within the ORACLES dataset is attributable to the dependence on AOD and scene albedo.
Kristina Pistone, Paquita Zuidema, Robert Wood, Michael Diamond, Arlindo M. da Silva, Gonzalo Ferrada, Pablo Saide, Rei Ueyama, Ju-Mee Ryoo, Leonhard Pfister, James Podolske, David Noone, Ryan Bennett, Eric Stith, Gregory Carmichael, Jens Redemann, Connor Flynn, Samuel LeBlanc, Michal Segal-Rozenhaimer, and Yohei Shinozuka
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1322, https://doi.org/10.5194/acp-2020-1322, 2021
Preprint under review for ACP
Short summary
Short summary
Using aircraft-based measurements off the Atlantic coast of Africa, we found that the springtime smoke plume there was strongly linearly correlated with the amount of water vapor in the atmosphere (where there is more smoke, there is more humidity). We see the same general feature in satellite-assimilated (reanalyses) and free-running models, which suggests that the humidity-smoke relationship is not a product of burning but originates over the continent and is transported without mixing.
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. Discuss., https://doi.org/10.5194/acp-2020-1218, https://doi.org/10.5194/acp-2020-1218, 2020
Preprint under review for ACP
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.
Yohei Shinozuka, Pablo E. Saide, Gonzalo A. Ferrada, Sharon P. Burton, Richard Ferrare, Sarah J. Doherty, Hamish Gordon, Karla Longo, Marc Mallet, Yan Feng, Qiaoqiao Wang, Yafang Cheng, Amie Dobracki, Steffen Freitag, Steven G. Howell, Samuel LeBlanc, Connor Flynn, Michal Segal-Rosenhaimer, Kristina Pistone, James R. Podolske, Eric J. Stith, Joseph Ryan Bennett, Gregory R. Carmichael, Arlindo da Silva, Ravi Govindaraju, Ruby Leung, Yang Zhang, Leonhard Pfister, Ju-Mee Ryoo, Jens Redemann, Robert Wood, and Paquita Zuidema
Atmos. Chem. Phys., 20, 11491–11526, https://doi.org/10.5194/acp-20-11491-2020, https://doi.org/10.5194/acp-20-11491-2020, 2020
Short summary
Short summary
In the southeast Atlantic, well-defined smoke plumes from Africa advect over marine boundary layer cloud decks; both are most extensive around September, when most of the smoke resides in the free troposphere. A framework is put forth for evaluating the performance of a range of global and regional atmospheric composition models against observations made during the NASA ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) airborne mission in September 2016.
Yohei Shinozuka, Meloë S. Kacenelenbogen, Sharon P. Burton, Steven G. Howell, Paquita Zuidema, Richard A. Ferrare, Samuel E. LeBlanc, Kristina Pistone, Stephen Broccardo, Jens Redemann, K. Sebastian Schmidt, Sabrina P. Cochrane, Marta Fenn, Steffen Freitag, Amie Dobracki, Michal Segal-Rosenheimer, and Connor J. Flynn
Atmos. Chem. Phys., 20, 11275–11285, https://doi.org/10.5194/acp-20-11275-2020, https://doi.org/10.5194/acp-20-11275-2020, 2020
Short summary
Short summary
To help satellite retrieval of aerosols and studies of their radiative effects, we demonstrate that daytime aerosol optical depth over low-level clouds is similar to that in neighboring clear skies at the same heights. Based on recent airborne lidar and sun photometer observations above the southeast Atlantic, the mean AOD difference at 532 nm is between 0 and -0.01, when comparing the cloudy and clear sides of cloud edges, with each up to 20 km wide.
Sabrina P. Cochrane, K. Sebastian Schmidt, Hong Chen, Peter Pilewskie, Scott Kittelman, Jens Redemann, Samuel LeBlanc, Kristina Pistone, Meloë Kacenelenbogen, Michal Segal Rozenhaimer, Yohei Shinozuka, Connor Flynn, Steven Platnick, Kerry Meyer, Rich Ferrare, Sharon Burton, Chris Hostetler, Steven Howell, Steffen Freitag, Amie Dobracki, and Sarah Doherty
Atmos. Meas. Tech., 12, 6505–6528, https://doi.org/10.5194/amt-12-6505-2019, https://doi.org/10.5194/amt-12-6505-2019, 2019
Short summary
Short summary
For two cases from the NASA ORACLES experiments, we retrieve aerosol and cloud properties and calculate a direct aerosol radiative effect (DARE). We investigate the relationship between DARE and the cloud albedo by specifying the albedo for which DARE transitions from a cooling to warming radiative effect. Our new aerosol retrieval algorithm is successful despite complexities associated with scenes that contain aerosols above clouds and decreases the uncertainty on retrieved aerosol parameters.
Kristina Pistone, Jens Redemann, Sarah Doherty, Paquita Zuidema, Sharon Burton, Brian Cairns, Sabrina Cochrane, Richard Ferrare, Connor Flynn, Steffen Freitag, Steven G. Howell, Meloë Kacenelenbogen, Samuel LeBlanc, Xu Liu, K. Sebastian Schmidt, Arthur J. Sedlacek III, Michal Segal-Rozenhaimer, Yohei Shinozuka, Snorre Stamnes, Bastiaan van Diedenhoven, Gerard Van Harten, and Feng Xu
Atmos. Chem. Phys., 19, 9181–9208, https://doi.org/10.5194/acp-19-9181-2019, https://doi.org/10.5194/acp-19-9181-2019, 2019
Short summary
Short summary
Understanding how smoke particles interact with sunlight is important in calculating their effects on climate, since some smoke is more scattering (cooling) and some is more absorbing (heating). Knowing this proportion is important for both satellite observations and climate models. We measured smoke properties in a recent aircraft-based field campaign off the west coast of Africa and present a comparison of these properties as measured using the six different, independent techniques available.
Andrew M. Sayer, N. Christina Hsu, Jaehwa Lee, Woogyung V. Kim, Sharon Burton, Marta A. Fenn, Richard A. Ferrare, Meloë Kacenelenbogen, Samuel LeBlanc, Kristina Pistone, Jens Redemann, Michal Segal-Rozenhaimer, Yohei Shinozuka, and Si-Chee Tsay
Atmos. Meas. Tech., 12, 3595–3627, https://doi.org/10.5194/amt-12-3595-2019, https://doi.org/10.5194/amt-12-3595-2019, 2019
Short summary
Short summary
Aerosols are small particles in the atmosphere such as dust or smoke. They are routinely monitored by satellites due to their importance for climate and air quality. However aerosols above clouds are more difficult to monitor. This study describes an improvement to a technique to monitor light-absorbing aerosols above clouds from four Earth-orbiting satellite instruments. The improved method is evaluated using data from the ORACLES field campaign, which measured these aerosols from aircraft.
Meloë S. Kacenelenbogen, Mark A. Vaughan, Jens Redemann, Stuart A. Young, Zhaoyan Liu, Yongxiang Hu, Ali H. Omar, Samuel LeBlanc, Yohei Shinozuka, John Livingston, Qin Zhang, and Kathleen A. Powell
Atmos. Chem. Phys., 19, 4933–4962, https://doi.org/10.5194/acp-19-4933-2019, https://doi.org/10.5194/acp-19-4933-2019, 2019
Short summary
Short summary
Significant efforts are required to estimate the direct radiative effects of aerosols above clouds (DAREcloudy). We have used a combination of passive and active A-Train satellite sensors and derive mainly positive global and regional DAREcloudy values (e.g., global seasonal values between 0.13 and 0.26 W m-2). Despite differences in methods and sensors, the DAREcloudy values in this study are generally higher than previously reported. We discuss the primary reasons for these higher estimates.
S. E. LeBlanc, P. Pilewskie, K. S. Schmidt, and O. Coddington
Atmos. Meas. Tech., 8, 1361–1383, https://doi.org/10.5194/amt-8-1361-2015, https://doi.org/10.5194/amt-8-1361-2015, 2015
Short summary
Short summary
Cloud properties are obtained via transmitted light that has interacted with cloud particles throughout its vertical extent. To achieve this, we introduce a new retrieval based on spectrally resolved measurements. We used 15 parameters to quantify spectral features in transmitted light modulated by cloud optical thickness, effective radius, and thermodynamic phase. When applied to ground-based measurements, this method results in a closer match to measured spectra than two other methods.
Xinxin Ye, Pargoal Arab, Ravan Ahmadov, Eric James, Georg A. Grell, Bradley Pierce, Aditya Kumar, Paul Makar, Jack Chen, Didier Davignon, Greg Carmichael, Gonzalo Ferrada, Jeff McQueen, Jianping Huang, Rajesh Kumar, Louisa Emmons, Farren L. Herron-Thorpe, Mark Parrington, Richard Engelen, Vincent-Henri Peuch, Arlindo da Silva, Amber Soja, Emily Gargulinski, Elizabeth Wiggins, Johnathan W. Hair, Marta Fenn, Taylor Shingler, Shobha Kondragunta, Alexei Lyapustin, Yujie Wang, Brent Holben, David Giles, and Pablo E. Saide
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-223, https://doi.org/10.5194/acp-2021-223, 2021
Preprint under review for ACP
Short summary
Short summary
Wildfire smoke has crucial impacts on air quality, while uncertainties in the numerical forecasts remain significant. We present an evaluation of twelve real-time forecasting systems. Comparison of predicted smoke emissions suggests a large spread in magnitudes with temporal patterns deviating from satellite detections. The performance for AOD and surface PM2.5 and their discrepancies highlighted the role of accurately represented spatiotemporal emission profiles, for improving smoke forecasts.
Yang Wang, Guangjie Zheng, Michael Jensen, Daniel Knopf, Alexander Laskin, Alyssa Matthews, David Mechem, Fan Mei, Ryan Moffet, Arthur Sedlacek, John Shilling, Stephen Springston, Amy Sullivan, Jason Tomlinson, Daniel Veghte, Rodney Weber, Robert Wood, Maria Zawadowicz, and Jian Wang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-300, https://doi.org/10.5194/acp-2021-300, 2021
Preprint under review for ACP
Short summary
Short summary
This manuscript reports the vertical profiles of trace gas and aerosol properties over the Eastern North Atlantic, a region of persistent but diverse subtropical marine boundary layer (MBL) clouds. We examined the key processes that drive the cloud condensation nuclei (CCN) population and how it varies with season and synoptic conditions. This study helps improve the model representation of the aerosol processes in the remote MBL, reducing the simulated aerosol indirect effects.
Hong Chen, Sebastian Schmidt, Michael D. King, Galina Wind, Anthony Bucholtz, Elizabeth A. Reid, Michal Segal-Rozenhaimer, William L. Smith, Patrick C. Taylor, Seiji Kato, and Peter Pilewskie
Atmos. Meas. Tech., 14, 2673–2697, https://doi.org/10.5194/amt-14-2673-2021, https://doi.org/10.5194/amt-14-2673-2021, 2021
Short summary
Short summary
In this paper, we accessed the shortwave irradiance derived from MODIS cloud optical properties by using aircraft measurements. We developed a data aggregation technique to parameterize spectral surface albedo by snow fraction in the Arctic. We found that undetected clouds have the most significant impact on the imagery-derived irradiance. This study suggests that passive imagery cloud detection could be improved through a multi-pixel approach that would make it more dependable in the Arctic.
Ju-Mee Ryoo, Leonhard Pfister, Rei Ueyama, Paquita Zuidema, Robert Wood, Ian Chang, and Jens Redemann
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-274, https://doi.org/10.5194/acp-2021-274, 2021
Preprint under review for ACP
Short summary
Short summary
Meteorology influences the aerosol-cloud interaction. Thus, it is critical to understand the meteorological characteristics during the deployment to better interpret the airborne measurement. Furthermore, it is crucial to know how different they are compared to the climatological mean in various temporal and spatial scales. This paper provides a thorough overview of the meteorology reflecting the coupled land-ocean-atmosphere system and the representativeness of the deployment months.
Siddhant Gupta, Greg M. McFarquhar, Joseph R. O'Brien, David J. Delene, Michael R. Poellot, Amie Dobracki, James R. Podolske, Jens Redemann, Samuel E. LeBlanc, Michal Segal-Rozenhaimer, and Kristina Pistone
Atmos. Chem. Phys., 21, 4615–4635, https://doi.org/10.5194/acp-21-4615-2021, https://doi.org/10.5194/acp-21-4615-2021, 2021
Short summary
Short summary
Observations from the 2016 NASA ObseRvations of Aerosols above CLouds and their intEractionS (ORACLES) field campaign examine how biomass burning aerosols from southern Africa affect marine stratocumulus cloud decks over the Southeast Atlantic. Instances of contact and separation between aerosols and clouds are examined to quantify the impact of aerosol mixing into cloud top on cloud drop numbers and sizes. This information is needed for improving Earth system models and satellite retrievals.
Isabelle Chiapello, Paola Formenti, Lydie Mbemba Kabuiku, Fabrice Ducos, Didier Tanré, and François Dulac
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1155, https://doi.org/10.5194/acp-2020-1155, 2021
Preprint under review for ACP
Hongbin Yu, Qian Tan, Lillian Zhou, Yaping Zhou, Huisheng Bian, Mian Chin, Claire L. Ryder, Robert C. Levy, Yaswant Pradhan, Yingxi Shi, Qianqian Song, Zhibo Zhang, Peter R. Colarco, Dongchul Kim, Lorraine A. Remer, Tianle Yuan, Olga Mayol-Bracero, and Brent N. Holben
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-73, https://doi.org/10.5194/acp-2021-73, 2021
Preprint under review for ACP
Short summary
Short summary
This study characterizes a historic African dust intrusion into the Caribbean Basin in June 2020 using satellites and NASA GEOS model. Dust emissions in West Africa were large albeit not extreme. However, a unique synoptic system accumulated the dust near the coast for about four days before it was ventilated. Although GEOS well reproduced satellite observed plume tracks, it substantially underestimated dust emissions and did not lift up dust high enough for ensuing long-range transport.
Dillon S. Dodson and Jennifer D. Small Griswold
Atmos. Chem. Phys., 21, 1937–1961, https://doi.org/10.5194/acp-21-1937-2021, https://doi.org/10.5194/acp-21-1937-2021, 2021
Short summary
Short summary
The results here reinforce findings from previous in situ studies of the marine boundary layer. It is found that turbulence is maximized in the middle of the stratocumulus layer from latent heating effects. Precipitation acts to increase turbulence in the sub-cloud layer, while acting to stabilize the entire boundary layer after the evaporation of precipitation in the sub-cloud has stopped. A negative correlation is present between the boundary layer height and turbulence.
Jens Redemann, Robert Wood, Paquita Zuidema, Sarah J. Doherty, Bernadette Luna, Samuel E. LeBlanc, Michael S. Diamond, Yohei Shinozuka, Ian Y. Chang, Rei Ueyama, Leonhard Pfister, Ju-Mee Ryoo, Amie N. Dobracki, Arlindo M. da Silva, Karla M. Longo, Meloë S. Kacenelenbogen, Connor J. Flynn, Kristina Pistone, Nichola M. Knox, Stuart J. Piketh, James M. Haywood, Paola Formenti, Marc Mallet, Philip Stier, Andrew S. Ackerman, Susanne E. Bauer, Ann M. Fridlind, Gregory R. Carmichael, Pablo E. Saide, Gonzalo A. Ferrada, Steven G. Howell, Steffen Freitag, Brian Cairns, Brent N. Holben, Kirk D. Knobelspiesse, Simone Tanelli, Tristan S. L'Ecuyer, Andrew M. Dzambo, Ousmane O. Sy, Greg M. McFarquhar, Michael R. Poellot, Siddhant Gupta, Joseph R. O'Brien, Athanasios Nenes, Mary Kacarab, Jenny P. S. Wong, Jennifer D. Small-Griswold, Kenneth L. Thornhill, David Noone, James R. Podolske, K. Sebastian Schmidt, Peter Pilewskie, Hong Chen, Sabrina P. Cochrane, Arthur J. Sedlacek, Timothy J. Lang, Eric Stith, Michal Segal-Rozenhaimer, Richard A. Ferrare, Sharon P. Burton, Chris A. Hostetler, David J. Diner, Felix C. Seidel, Steven E. Platnick, Jeffrey S. Myers, Kerry G. Meyer, Douglas A. Spangenberg, Hal Maring, and Lan Gao
Atmos. Chem. Phys., 21, 1507–1563, https://doi.org/10.5194/acp-21-1507-2021, https://doi.org/10.5194/acp-21-1507-2021, 2021
Short summary
Short summary
Southern Africa produces significant biomass burning emissions whose impacts on regional and global climate are poorly understood. ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) is a 5-year NASA investigation designed to study the key processes that determine these climate impacts. The main purpose of this paper is to familiarize the broader scientific community with the ORACLES project, the dataset it produced, and the most important initial findings.
Sabrina P. Cochrane, K. Sebastian Schmidt, Hong Chen, Peter Pilewskie, Scott Kittelman, Jens Redemann, Samuel LeBlanc, Kristina Pistone, Meloë Kacenelenbogen, Michal Segal Rozenhaimer, Yohei Shinozuka, Connor Flynn, Amie Dobracki, Paquita Zuidema, Steven Howell, Steffen Freitag, and Sarah Doherty
Atmos. Meas. Tech., 14, 567–593, https://doi.org/10.5194/amt-14-567-2021, https://doi.org/10.5194/amt-14-567-2021, 2021
Short summary
Short summary
Based on observations from the 2016 and 2017 field campaigns of ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS), this work establishes an observationally driven link from mid-visible aerosol optical depth (AOD) and other scene parameters to broadband shortwave irradiance (and by extension the direct aerosol radiative effect, DARE). The majority of the case-to-case DARE variability within the ORACLES dataset is attributable to the dependence on AOD and scene albedo.
Jim M. Haywood, Steven J. Abel, Paul A. Barrett, Nicolas Bellouin, Alan Blyth, Keith N. Bower, Melissa Brooks, Ken Carslaw, Haochi Che, Hugh Coe, Michael I. Cotterell, Ian Crawford, Zhiqiang Cui, Nicholas Davies, Beth Dingley, Paul Field, Paola Formenti, Hamish Gordon, Martin de Graaf, Ross Herbert, Ben Johnson, Anthony C. Jones, Justin M. Langridge, Florent Malavelle, Daniel G. Partridge, Fanny Peers, Jens Redemann, Philip Stier, Kate Szpek, Jonathan W. Taylor, Duncan Watson-Parris, Robert Wood, Huihui Wu, and Paquita Zuidema
Atmos. Chem. Phys., 21, 1049–1084, https://doi.org/10.5194/acp-21-1049-2021, https://doi.org/10.5194/acp-21-1049-2021, 2021
Short summary
Short summary
Every year, the seasonal cycle of biomass burning from agricultural practices in Africa creates a huge plume of smoke that travels many thousands of kilometres over the Atlantic Ocean. This study provides an overview of a measurement campaign called the cloud–aerosol–radiation interaction and forcing for year 2017 (CLARIFY-2017) and documents the rationale, deployment strategy, observations, and key results from the campaign which utilized the heavily equipped FAAM atmospheric research aircraft.
Kristina Pistone, Paquita Zuidema, Robert Wood, Michael Diamond, Arlindo M. da Silva, Gonzalo Ferrada, Pablo Saide, Rei Ueyama, Ju-Mee Ryoo, Leonhard Pfister, James Podolske, David Noone, Ryan Bennett, Eric Stith, Gregory Carmichael, Jens Redemann, Connor Flynn, Samuel LeBlanc, Michal Segal-Rozenhaimer, and Yohei Shinozuka
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1322, https://doi.org/10.5194/acp-2020-1322, 2021
Preprint under review for ACP
Short summary
Short summary
Using aircraft-based measurements off the Atlantic coast of Africa, we found that the springtime smoke plume there was strongly linearly correlated with the amount of water vapor in the atmosphere (where there is more smoke, there is more humidity). We see the same general feature in satellite-assimilated (reanalyses) and free-running models, which suggests that the humidity-smoke relationship is not a product of burning but originates over the continent and is transported without mixing.
Tianle Yuan, Hua Song, Robert Wood, Johannes Mohrmann, Kerry Meyer, Lazaros Oreopoulos, and Steven Platnick
Atmos. Meas. Tech., 13, 6989–6997, https://doi.org/10.5194/amt-13-6989-2020, https://doi.org/10.5194/amt-13-6989-2020, 2020
Short summary
Short summary
We use deep transfer learning techniques to classify satellite cloud images into different morphology types. It achieves the state-of-the-art results and can automatically process a large amount of satellite data. The algorithm will help low-cloud researchers to better understand their mesoscale organizations.
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. Discuss., https://doi.org/10.5194/acp-2020-1218, https://doi.org/10.5194/acp-2020-1218, 2020
Preprint under review for ACP
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.
Danitza Klopper, Paola Formenti, Andreas Namwoonde, Mathieu Cazaunau, Servanne Chevaillier, Anaïs Feron, Cécile Gaimoz, Patrick Hease, Fadi Lahmidi, Cécile Mirande-Bret, Sylvain Triquet, Zirui Zeng, and Stuart J. Piketh
Atmos. Chem. Phys., 20, 15811–15833, https://doi.org/10.5194/acp-20-15811-2020, https://doi.org/10.5194/acp-20-15811-2020, 2020
Short summary
Short summary
The chemical composition of aerosol particles is very important as it determines to which extent they can affect the Earth's climate by acting with solar light and modifying the properties of clouds. The South Atlantic region is a remote and under-explored region to date where these effects could be important. The measurements presented in this paper consist in the analysis of samples collected at a coastal site in Namibia. The first long-term source apportionment is presented and discussed.
Stefan Noël, Maximilian Reuter, Michael Buchwitz, Jakob Borchardt, Michael Hilker, Heinrich Bovensmann, John P. Burrows, Antonio Di Noia, Hiroshi Suto, Yukio Yoshida, Matthias Buschmann, Nicholas M. Deutscher, Dietrich G. Feist, David W. T. Griffith, Frank Hase, Rigel Kivi, Isamu Morino, Justus Notholt, Hirofumi Ohyama, Christof Petri, James R. Podolske, David F. Pollard, Mahesh Kumar Sha, Kei Shiomi, Ralf Sussmann, Yao Té, Voltaire A. Velazco, and Thorsten Warneke
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-453, https://doi.org/10.5194/amt-2020-453, 2020
Revised manuscript accepted for AMT
Short summary
Short summary
We present first GOSAT and GOSAT-2 XCO2 data derived with the FOCAL retrieval algorithm.
Comparisons of the GOSAT FOCAL product with other data reveal a long-term agreement within about 1 ppm over one decade, differences in seasonal variations of about 0.5 ppm and a mean regional bias to ground based TCCON data of 0.56 ppm with a mean scatter of 1.89 ppm.
GOSAT-2 FOCAL data are considered to be preliminary only, but first comparisons show that they compare well with the GOSAT FOCAL results.
Nick Schutgens, Oleg Dubovik, Otto Hasekamp, Omar Torres, Hiren Jethva, Peter J. T. Leonard, Pavel Litvinov, Jens Redemann, Yohei Shinozuka, Gerrit de Leeuw, Stefan Kinne, Thomas Popp, Michael Schulz, and Philip Stier
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1207, https://doi.org/10.5194/acp-2020-1207, 2020
Revised manuscript accepted for ACP
Short summary
Short summary
Absorptive aerosol has a potentially large impact on climate change. We evaluate and intercompare four global satellite datasets of Absorptive Aerosol Optical Depth (AAOD) and Single Scattering Albedo (SSA). We show that these datasets show reasonable correlations with the AERONET reference although significant biases remain. In a follow-up paper we show that these observations nevertheless can be used for model evaluation.
Clarissa Baldo, Paola Formenti, Sophie Nowak, Servanne Chevaillier, Mathieu Cazaunau, Edouard Pangui, Claudia Di Biagio, Jean-Francois Doussin, Konstantin Ignatyev, Pavla Dagsson-Waldhauserova, Olafur Arnalds, A. Robert MacKenzie, and Zongbo Shi
Atmos. Chem. Phys., 20, 13521–13539, https://doi.org/10.5194/acp-20-13521-2020, https://doi.org/10.5194/acp-20-13521-2020, 2020
Short summary
Short summary
We showed that Icelandic dust has a fundamentally different chemical and mineralogical composition from low-latitude dust. In particular, magnetite is as high as 1 %–2 % of the total dust mass. Our results suggest that Icelandic dust may have an important impact on the radiation balance in the subpolar and polar regions.
Augustin Mortier, Jonas Gliß, Michael Schulz, Wenche Aas, Elisabeth Andrews, Huisheng Bian, Mian Chin, Paul Ginoux, Jenny Hand, Brent Holben, Hua Zhang, Zak Kipling, Alf Kirkevåg, Paolo Laj, Thibault Lurton, Gunnar Myhre, David Neubauer, Dirk Olivié, Knut von Salzen, Ragnhild Bieltvedt Skeie, Toshihiko Takemura, and Simone Tilmes
Atmos. Chem. Phys., 20, 13355–13378, https://doi.org/10.5194/acp-20-13355-2020, https://doi.org/10.5194/acp-20-13355-2020, 2020
Short summary
Short summary
We present a multiparameter analysis of the aerosol trends over the last 2 decades in the different regions of the world. In most of the regions, ground-based observations show a decrease in aerosol content in both the total atmospheric column and at the surface. The use of climate models, assessed against these observations, reveals however an increase in the total aerosol load, which is not seen with the sole use of observation due to partial coverage in space and time.
Marc Mallet, Fabien Solmon, Pierre Nabat, Nellie Elguindi, Fabien Waquet, Dominique Bouniol, Andrew Mark Sayer, Kerry Meyer, Romain Roehrig, Martine Michou, Paquita Zuidema, Cyrille Flamant, Jens Redemann, and Paola Formenti
Atmos. Chem. Phys., 20, 13191–13216, https://doi.org/10.5194/acp-20-13191-2020, https://doi.org/10.5194/acp-20-13191-2020, 2020
Short summary
Short summary
This paper presents numerical simulations using two regional climate models to study the impact of biomass fire plumes from central Africa on the radiative balance of this region. The results indicate that biomass fires can either warm the regional climate when they are located above low clouds or cool it when they are located above land. They can also alter sea and land surface temperatures by decreasing solar radiation at the surface. Finally, they can also modify the atmospheric dynamics.
Maria A. Zawadowicz, Kaitlyn Suski, Jiumeng Liu, Mikhail Pekour, Jerome Fast, Fan Mei, Arthur Sedlacek, Stephen Springston, Yang Wang, Rahul A. Zaveri, Robert Wood, Jian Wang, and John E. Shilling
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-887, https://doi.org/10.5194/acp-2020-887, 2020
Revised manuscript accepted for ACP
Short summary
Short summary
This paper describes the results of a recent field campaign in the Eastern North Atlantic, where two mass spectrometers were deployed aboard a research aircraft to measure the chemistry of aerosols and trace gases. Very clean conditions were found, dominated by local sulfate-rich acidic aerosol and very aged organics. Evidence of long-range transport of aerosols from the continents has also been identified.
Johannes Mohrmann, Robert Wood, Tianle Yuan, Hua Song, Ryan Eastman, and Lazaros Oreopoulos
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1026, https://doi.org/10.5194/acp-2020-1026, 2020
Revised manuscript under review for ACP
Short summary
Short summary
Observations of marine boundary layer conditions are composited by cloud type, based on a new classification dataset. It is found that two cloud types, representing regions of clustered and suppressed low-level clouds, occur in very similar large-scale conditions, but are distinguished from each other by considering low-level circulation and surface wind fields, validating prior results from modelling.
Steven G. Howell, Steffen Freitag, Amie Dobracki, Nikolai Smirnow, and Arthur J. Sedlacek III
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-416, https://doi.org/10.5194/amt-2020-416, 2020
Preprint under review for AMT
Short summary
Short summary
Small particles in the air play have important effects on visibility, clouds, and human health. For the ORACLES project we got a new particle sizing instrument that is fast, works over the most important particle sizes, and avoids some of the issues that plague other optical particle sizers. Unfortunately it sees particles much smaller than they really are, probably because they heat up and evaporate. We show a crude correction and speculate why these particles heat so much more than expected.
Katta Vijayakumar, Panuganti C. S. Devara, Sunil M. Sonbawne, David M. Giles, Brent N. Holben, Sarangam Vijaya Bhaskara Rao, and Chalicheemalapalli K. Jayasankar
Atmos. Meas. Tech., 13, 5569–5593, https://doi.org/10.5194/amt-13-5569-2020, https://doi.org/10.5194/amt-13-5569-2020, 2020
Short summary
Short summary
The direct-Sun and inversion products of urban atmospheric aerosols, obtained from a Cimel Sun–sky radiometer in Pune, India, under the AERONET program since October 2004, have been reported in this paper. The mean seasonal variations in AOD from cloud-free days indicated greater values during the monsoon season, revealing dominance of hygroscopic aerosols over the station. Such results are sparse in India and are important for estimating aerosol radiative forcing and validating climate models.
Aurélien Chauvigné, Fabien Waquet, Frédérique Auriol, Luc Blarel, Cyril Delegove, Oleg Dubovik, Cyrille Flamant, Marco Gaetani, Philippe Goloub, Rodrigue Loisil, Marc Mallet, Jean-Marc Nicolas, Frédéric Parol, Fanny Peers, Benjamin Torres, and Paola Formenti
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-992, https://doi.org/10.5194/acp-2020-992, 2020
Revised manuscript accepted for ACP
Short summary
Short summary
The work presents aerosol above cloud properties close to the Namibian coast from a combination of airborne passive remote sensings. The complete analyse of aerosol and cloud optical properties as well as their microphysical and radiative properties allow us to better identify impacts of biomass burning emissions. This work also give a complete view of key-parameters to constrain climat models in case aerosol and cloud coexist in the troposphere.
Yohei Shinozuka, Pablo E. Saide, Gonzalo A. Ferrada, Sharon P. Burton, Richard Ferrare, Sarah J. Doherty, Hamish Gordon, Karla Longo, Marc Mallet, Yan Feng, Qiaoqiao Wang, Yafang Cheng, Amie Dobracki, Steffen Freitag, Steven G. Howell, Samuel LeBlanc, Connor Flynn, Michal Segal-Rosenhaimer, Kristina Pistone, James R. Podolske, Eric J. Stith, Joseph Ryan Bennett, Gregory R. Carmichael, Arlindo da Silva, Ravi Govindaraju, Ruby Leung, Yang Zhang, Leonhard Pfister, Ju-Mee Ryoo, Jens Redemann, Robert Wood, and Paquita Zuidema
Atmos. Chem. Phys., 20, 11491–11526, https://doi.org/10.5194/acp-20-11491-2020, https://doi.org/10.5194/acp-20-11491-2020, 2020
Short summary
Short summary
In the southeast Atlantic, well-defined smoke plumes from Africa advect over marine boundary layer cloud decks; both are most extensive around September, when most of the smoke resides in the free troposphere. A framework is put forth for evaluating the performance of a range of global and regional atmospheric composition models against observations made during the NASA ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) airborne mission in September 2016.
Yohei Shinozuka, Meloë S. Kacenelenbogen, Sharon P. Burton, Steven G. Howell, Paquita Zuidema, Richard A. Ferrare, Samuel E. LeBlanc, Kristina Pistone, Stephen Broccardo, Jens Redemann, K. Sebastian Schmidt, Sabrina P. Cochrane, Marta Fenn, Steffen Freitag, Amie Dobracki, Michal Segal-Rosenheimer, and Connor J. Flynn
Atmos. Chem. Phys., 20, 11275–11285, https://doi.org/10.5194/acp-20-11275-2020, https://doi.org/10.5194/acp-20-11275-2020, 2020
Short summary
Short summary
To help satellite retrieval of aerosols and studies of their radiative effects, we demonstrate that daytime aerosol optical depth over low-level clouds is similar to that in neighboring clear skies at the same heights. Based on recent airborne lidar and sun photometer observations above the southeast Atlantic, the mean AOD difference at 532 nm is between 0 and -0.01, when comparing the cloudy and clear sides of cloud edges, with each up to 20 km wide.
David O. De Haan, Lelia N. Hawkins, Kevin Jansen, Hannah G. Welsh, Raunak Pednekar, Alexia de Loera, Natalie G. Jimenez, Margaret A. Tolbert, Mathieu Cazaunau, Aline Gratien, Antonin Bergé, Edouard Pangui, Paola Formenti, and Jean-François Doussin
Atmos. Chem. Phys., 20, 9581–9590, https://doi.org/10.5194/acp-20-9581-2020, https://doi.org/10.5194/acp-20-9581-2020, 2020
Short summary
Short summary
When exposed to glyoxal in chamber experiments, dry ammonium or methylammonium sulfate particles turn brown immediately and reversibly without increasing in size. Much less browning was observed on wet aerosol particles, and no browning was observed with sodium sulfate aerosol. While estimated dry aerosol light absorption caused by background glyoxal (70 ppt) is insignificant compared to that of secondary brown carbon overall, in polluted regions this process could be a source of brown carbon.
Francesca Gallo, Janek Uin, Stephen Springston, Jian Wang, Guangjie Zheng, Chongai Kuang, Robert Wood, Eduardo B. Azevedo, Allison McComiskey, Fan Mei, Adam Theisen, Jenni Kyrouac, and Allison C. Aiken
Atmos. Chem. Phys., 20, 7553–7573, https://doi.org/10.5194/acp-20-7553-2020, https://doi.org/10.5194/acp-20-7553-2020, 2020
Short summary
Short summary
Continuous high-time-resolution ambient data can include periods when aerosol properties do not represent regional aerosol processes due to high-concentration local events. We develop a novel aerosol mask at the U.S. Department of Energy’s Atmospheric Radiation Measurement (ARM) facility in the eastern North Atlantic (ENA). We use two ground sites to validate the mask, include a comparison with aircraft overflights, and provide guidance to increase data quality at ENA and other locations.
Daniel J. Miller, Michal Segal-Rozenhaimer, Kirk Knobelspiesse, Jens Redemann, Brian Cairns, Mikhail Alexandrov, Bastiaan van Diedenhoven, and Andrzej Wasilewski
Atmos. Meas. Tech., 13, 3447–3470, https://doi.org/10.5194/amt-13-3447-2020, https://doi.org/10.5194/amt-13-3447-2020, 2020
Short summary
Short summary
A neural network (NN) is developed and used to retrieve cloud microphysical properties from multiangular and multispectral polarimetric remote sensing observations. The NN is applied to research scanning polarimeter (RSP) observations obtained during the ORACLES field campaign and compared to other co-located remote sensing retrievals of cloud effective radius and optical thickness. A NN approach can advance more complex iterative search retrieval algorithms by providing a quick initial guess.
Alexander Sinyuk, Brent N. Holben, Thomas F. Eck, David M. Giles, Ilya Slutsker, Sergey Korkin, Joel S. Schafer, Alexander Smirnov, Mikhail Sorokin, and Alexei Lyapustin
Atmos. Meas. Tech., 13, 3375–3411, https://doi.org/10.5194/amt-13-3375-2020, https://doi.org/10.5194/amt-13-3375-2020, 2020
Benjamin Marchant, Steven Platnick, Kerry Meyer, and Galina Wind
Atmos. Meas. Tech., 13, 3263–3275, https://doi.org/10.5194/amt-13-3263-2020, https://doi.org/10.5194/amt-13-3263-2020, 2020
Short summary
Short summary
Multilayer cloud scenes (such as an ice cloud overlapping a liquid cloud) are common in the Earth's atmosphere and are quite difficult to detect from space. The detection of multilayer clouds is important to better understand how they interact with the light and their impact on the climate. So, for the instrument MODIS an algorithm has been developed to detect those clouds, and this paper presents an evaluation of this algorithm by comparing it with
other instruments.
Pablo E. Saide, Meng Gao, Zifeng Lu, Daniel L. Goldberg, David G. Streets, Jung-Hun Woo, Andreas Beyersdorf, Chelsea A. Corr, Kenneth L. Thornhill, Bruce Anderson, Johnathan W. Hair, Amin R. Nehrir, Glenn S. Diskin, Jose L. Jimenez, Benjamin A. Nault, Pedro Campuzano-Jost, Jack Dibb, Eric Heim, Kara D. Lamb, Joshua P. Schwarz, Anne E. Perring, Jhoon Kim, Myungje Choi, Brent Holben, Gabriele Pfister, Alma Hodzic, Gregory R. Carmichael, Louisa Emmons, and James H. Crawford
Atmos. Chem. Phys., 20, 6455–6478, https://doi.org/10.5194/acp-20-6455-2020, https://doi.org/10.5194/acp-20-6455-2020, 2020
Short summary
Short summary
Air quality forecasts over the Korean Peninsula captured aerosol optical depth but largely overpredicted surface PM during a Chinese haze transport event. Model deficiency was related to the calculation of optical properties. In order to improve it, aerosol size representation needs to be refined in the calculations, and the representation of aerosol properties, such as size distribution, chemical composition, refractive index, hygroscopicity parameter, and density, needs to be improved.
Chenxi Wang, Steven Platnick, Kerry Meyer, Zhibo Zhang, and Yaping Zhou
Atmos. Meas. Tech., 13, 2257–2277, https://doi.org/10.5194/amt-13-2257-2020, https://doi.org/10.5194/amt-13-2257-2020, 2020
Short summary
Short summary
A machine-learning (ML)-based approach that can be used for cloud mask and phase detection is developed. An all-day model that uses infrared (IR) observations and a daytime model that uses shortwave and IR observations from a passive instrument are trained separately for different surface types. The training datasets are selected by using reference pixel types from collocated space lidar. The ML approach is validated carefully and the overall performance is better than traditional methods.
Nelson Bègue, Lerato Shikwambana, Hassan Bencherif, Juan Pallotta, Venkataraman Sivakumar, Elian Wolfram, Nkanyiso Mbatha, Facundo Orte, David Jean Du Preez, Marion Ranaivombola, Stuart Piketh, and Paola Formenti
Ann. Geophys., 38, 395–420, https://doi.org/10.5194/angeo-38-395-2020, https://doi.org/10.5194/angeo-38-395-2020, 2020
Short summary
Short summary
This study investigates the influence of the 2015 Calbuco eruption (41.2°S, 72.4°W; Chile) on the total columnar aerosol optical properties in the Southern Hemisphere. The well-known technique of sun photometry was applied to the investigation of the transport and the spatio-temporal evolution of the optical properties of the volcanic plume. The CIMEL sun photometer measurements performed over six South American and three African sites were statistically analyzed.
Mary Kacarab, K. Lee Thornhill, Amie Dobracki, Steven G. Howell, Joseph R. O'Brien, Steffen Freitag, Michael R. Poellot, Robert Wood, Paquita Zuidema, Jens Redemann, and Athanasios Nenes
Atmos. Chem. Phys., 20, 3029–3040, https://doi.org/10.5194/acp-20-3029-2020, https://doi.org/10.5194/acp-20-3029-2020, 2020
Short summary
Short summary
We find that extensive biomass burning aerosol plumes from southern Africa can profoundly influence clouds in the southeastern Atlantic. Concurrent variations in vertical velocity, however, are found to magnify the relationship between boundary layer aerosol and the cloud droplet number. Neglecting these covariances may strongly bias the sign and magnitude of aerosol impacts on the cloud droplet number.
Sam Pennypacker, Michael Diamond, and Robert Wood
Atmos. Chem. Phys., 20, 2341–2351, https://doi.org/10.5194/acp-20-2341-2020, https://doi.org/10.5194/acp-20-2341-2020, 2020
Short summary
Short summary
Using observations from instruments deployed to a small island in the southeast Atlantic, we study days when the atmospheric concentrations of particles near the surface are exceptionally low. Interestingly, these ultra-clean boundary layers occur in the same months as the smokiest boundary layers associated with biomass burning in Africa. We find evidence that enhancements in drizzle scavenging, on top of a seasonal maximum in cloudiness and precipitation, likely drive these conditions.
Claudia Di Biagio, Paola Formenti, Yves Balkanski, Lorenzo Caponi, Mathieu Cazaunau, Edouard Pangui, Emilie Journet, Sophie Nowak, Meinrat O. Andreae, Konrad Kandler, Thuraya Saeed, Stuart Piketh, David Seibert, Earle Williams, and Jean-François Doussin
Atmos. Chem. Phys., 19, 15503–15531, https://doi.org/10.5194/acp-19-15503-2019, https://doi.org/10.5194/acp-19-15503-2019, 2019
Short summary
Short summary
This paper presents a new dataset of laboratory measurements of the shortwave (SW) spectral complex refractive index and single-scattering albedo (SSA) for global mineral dust aerosols of varying origin and composition. Our results show that the dust refractive index and SSA vary strongly from source to source, mostly due to particle iron content changes. We recommend that source-dependent values of the SW spectral refractive index and SSA be used in models and remote sensing applications.
Patrick Chazette, Cyrille Flamant, Julien Totems, Marco Gaetani, Gwendoline Smith, Alexandre Baron, Xavier Landsheere, Karine Desboeufs, Jean-François Doussin, and Paola Formenti
Atmos. Chem. Phys., 19, 14979–15005, https://doi.org/10.5194/acp-19-14979-2019, https://doi.org/10.5194/acp-19-14979-2019, 2019
Short summary
Short summary
Evolution of the vertical distribution and optical properties of aerosols in the free troposphere is analysed for the first time over the Namibian coast, a region where uncertainties on aerosol–cloud coupling in climate simulations are significant. The high variability of atmospheric aerosol composition is highlighted using a combination of ground-based, airborne and space-borne lidar. Aerosols are mainly transported from Angola, but part of the highest aerosol layer may come from South America.
Sabrina P. Cochrane, K. Sebastian Schmidt, Hong Chen, Peter Pilewskie, Scott Kittelman, Jens Redemann, Samuel LeBlanc, Kristina Pistone, Meloë Kacenelenbogen, Michal Segal Rozenhaimer, Yohei Shinozuka, Connor Flynn, Steven Platnick, Kerry Meyer, Rich Ferrare, Sharon Burton, Chris Hostetler, Steven Howell, Steffen Freitag, Amie Dobracki, and Sarah Doherty
Atmos. Meas. Tech., 12, 6505–6528, https://doi.org/10.5194/amt-12-6505-2019, https://doi.org/10.5194/amt-12-6505-2019, 2019
Short summary
Short summary
For two cases from the NASA ORACLES experiments, we retrieve aerosol and cloud properties and calculate a direct aerosol radiative effect (DARE). We investigate the relationship between DARE and the cloud albedo by specifying the albedo for which DARE transitions from a cooling to warming radiative effect. Our new aerosol retrieval algorithm is successful despite complexities associated with scenes that contain aerosols above clouds and decreases the uncertainty on retrieved aerosol parameters.
Joel S. Schafer, Tom F. Eck, Brent N. Holben, Kenneth L. Thornhill, Luke D. Ziemba, Patricia Sawamura, Richard H. Moore, Ilya Slutsker, Bruce E. Anderson, Alexander Sinyuk, David M. Giles, Alexander Smirnov, Andreas J. Beyersdorf, and Edward L. Winstead
Atmos. Meas. Tech., 12, 5289–5301, https://doi.org/10.5194/amt-12-5289-2019, https://doi.org/10.5194/amt-12-5289-2019, 2019
Short summary
Short summary
Two independent datasets of column-integrated size distributions of atmospheric aerosols were compared during four 1-month regional campaigns from 2011 to 2014 in four US states. One set of measurements was from observations at multiple locations at the surface using retrievals from sun photometers, while the other relied on in situ aircraft sampling. These campaigns represent the most extensive comparison of AERONET size distributions with aircraft sampling of particle size on record.
Jonathan K. P. Shonk, Jui-Yuan Christine Chiu, Alexander Marshak, David M. Giles, Chiung-Huei Huang, Gerald G. Mace, Sally Benson, Ilya Slutsker, and Brent N. Holben
Atmos. Meas. Tech., 12, 5087–5099, https://doi.org/10.5194/amt-12-5087-2019, https://doi.org/10.5194/amt-12-5087-2019, 2019
Short summary
Short summary
Retrievals of cloud optical depth made using AERONET radiometers in “cloud mode” rely on the assumption that all cloud is liquid. The presence of ice cloud therefore introduces errors in the retrieved optical depth, which can be over 25 in optically thick ice clouds. However, such clouds are not frequent and the long-term mean optical depth error is about 3 for a sample of real clouds. A correction equation could improve the retrieval further, although this would require extra instrumentation.
Marc D. Mallet, Barbara D'Anna, Aurélie Même, Maria Chiara Bove, Federico Cassola, Giandomenico Pace, Karine Desboeufs, Claudia Di Biagio, Jean-Francois Doussin, Michel Maille, Dario Massabò, Jean Sciare, Pascal Zapf, Alcide Giorgio di Sarra, and Paola Formenti
Atmos. Chem. Phys., 19, 11123–11142, https://doi.org/10.5194/acp-19-11123-2019, https://doi.org/10.5194/acp-19-11123-2019, 2019
Short summary
Short summary
We present findings from a summertime field campaign at the remote island of Lampedusa in the central Mediterranean Sea. We show that the aerosol loading is similar to coastal sites around the Mediterranean. We observe higher loadings of sulfate and aged organic aerosol from air masses transported over the central and eastern Mediterranean in comparison to those from the western Mediterranean. These results highlight the rarity of pristine air masses, even in remote marine environments.
Myungje Choi, Hyunkwang Lim, Jhoon Kim, Seoyoung Lee, Thomas F. Eck, Brent N. Holben, Michael J. Garay, Edward J. Hyer, Pablo E. Saide, and Hongqing Liu
Atmos. Meas. Tech., 12, 4619–4641, https://doi.org/10.5194/amt-12-4619-2019, https://doi.org/10.5194/amt-12-4619-2019, 2019
Short summary
Short summary
Satellite-based aerosol optical depth (AOD) products have been improved continuously and available from multiple low Earth orbit sensors, such as MODIS, MISR, and VIIRS, and geostationary sensors, such as GOCI and AHI, over East Asia. These multi-satellite AOD products are validated, intercompared, analyzed, and integrated to understand different characteristics, such as quality and spatio-temporal coverage, focused on several aerosol transportation cases during the 2016 KORUS-AQ campaign.
Huizheng Che, Ke Gui, Xiangao Xia, Yaqiang Wang, Brent N. Holben, Philippe Goloub, Emilio Cuevas-Agulló, Hong Wang, Yu Zheng, Hujia Zhao, and Xiaoye Zhang
Atmos. Chem. Phys., 19, 10497–10523, https://doi.org/10.5194/acp-19-10497-2019, https://doi.org/10.5194/acp-19-10497-2019, 2019
Short summary
Short summary
A comprehensive assessment of the global and regional AOD trends over the past 37 years (1980–2016) is presented. AOD observations from both AERONET and CARSNET were used for the first time to assess the performance of the MERRA-2 AOD dataset on a global scale. Based on statistical models, we found the meteorological parameters explained a larger proportion of the regional AOD variability (20.4 %–2.8 %) when compared with emission factors (0 %%–56 %).
Fanny Peers, Peter Francis, Cathryn Fox, Steven J. Abel, Kate Szpek, Michael I. Cotterell, Nicholas W. Davies, Justin M. Langridge, Kerry G. Meyer, Steven E. Platnick, and Jim M. Haywood
Atmos. Chem. Phys., 19, 9595–9611, https://doi.org/10.5194/acp-19-9595-2019, https://doi.org/10.5194/acp-19-9595-2019, 2019
Short summary
Short summary
The measurements from the geostationary satellite MSG/SEVIRI are used to retrieve the cloud and above-cloud aerosol properties over the South Atlantic. The technique relies on the spectral contrast and the magnitude of the signal in the visible to shortwave infrared region as well as the atmospheric correction based on forecasted water vapour profiles. The sensitivity analysis and the stability of the retrieval over time show great potential of the high-temporal-resolution observations.
Kristina Pistone, Jens Redemann, Sarah Doherty, Paquita Zuidema, Sharon Burton, Brian Cairns, Sabrina Cochrane, Richard Ferrare, Connor Flynn, Steffen Freitag, Steven G. Howell, Meloë Kacenelenbogen, Samuel LeBlanc, Xu Liu, K. Sebastian Schmidt, Arthur J. Sedlacek III, Michal Segal-Rozenhaimer, Yohei Shinozuka, Snorre Stamnes, Bastiaan van Diedenhoven, Gerard Van Harten, and Feng Xu
Atmos. Chem. Phys., 19, 9181–9208, https://doi.org/10.5194/acp-19-9181-2019, https://doi.org/10.5194/acp-19-9181-2019, 2019
Short summary
Short summary
Understanding how smoke particles interact with sunlight is important in calculating their effects on climate, since some smoke is more scattering (cooling) and some is more absorbing (heating). Knowing this proportion is important for both satellite observations and climate models. We measured smoke properties in a recent aircraft-based field campaign off the west coast of Africa and present a comparison of these properties as measured using the six different, independent techniques available.
Andrew M. Sayer, N. Christina Hsu, Jaehwa Lee, Woogyung V. Kim, Sharon Burton, Marta A. Fenn, Richard A. Ferrare, Meloë Kacenelenbogen, Samuel LeBlanc, Kristina Pistone, Jens Redemann, Michal Segal-Rozenhaimer, Yohei Shinozuka, and Si-Chee Tsay
Atmos. Meas. Tech., 12, 3595–3627, https://doi.org/10.5194/amt-12-3595-2019, https://doi.org/10.5194/amt-12-3595-2019, 2019
Short summary
Short summary
Aerosols are small particles in the atmosphere such as dust or smoke. They are routinely monitored by satellites due to their importance for climate and air quality. However aerosols above clouds are more difficult to monitor. This study describes an improvement to a technique to monitor light-absorbing aerosols above clouds from four Earth-orbiting satellite instruments. The improved method is evaluated using data from the ORACLES field campaign, which measured these aerosols from aircraft.
Dillon S. Dodson and Jennifer D. Small Griswold
Atmos. Chem. Phys., 19, 7297–7317, https://doi.org/10.5194/acp-19-7297-2019, https://doi.org/10.5194/acp-19-7297-2019, 2019
Short summary
Short summary
This work looks at how the amount of aerosols contained in cloud affects the spatial orientation of the cloud droplets. Droplet orientation is important because it can lead to changes in the amount of time it takes precipitation to form. The results show that the aerosol amount does not have any effect on the droplet orientation. It is found however that the droplets are spaced closer together (there is increased droplet clustering) at cloud edge and top, as compared to center and bottom.
Meloë S. Kacenelenbogen, Mark A. Vaughan, Jens Redemann, Stuart A. Young, Zhaoyan Liu, Yongxiang Hu, Ali H. Omar, Samuel LeBlanc, Yohei Shinozuka, John Livingston, Qin Zhang, and Kathleen A. Powell
Atmos. Chem. Phys., 19, 4933–4962, https://doi.org/10.5194/acp-19-4933-2019, https://doi.org/10.5194/acp-19-4933-2019, 2019
Short summary
Short summary
Significant efforts are required to estimate the direct radiative effects of aerosols above clouds (DAREcloudy). We have used a combination of passive and active A-Train satellite sensors and derive mainly positive global and regional DAREcloudy values (e.g., global seasonal values between 0.13 and 0.26 W m-2). Despite differences in methods and sensors, the DAREcloudy values in this study are generally higher than previously reported. We discuss the primary reasons for these higher estimates.
Marc Mallet, Pierre Nabat, Paquita Zuidema, Jens Redemann, Andrew Mark Sayer, Martin Stengel, Sebastian Schmidt, Sabrina Cochrane, Sharon Burton, Richard Ferrare, Kerry Meyer, Pablo Saide, Hiren Jethva, Omar Torres, Robert Wood, David Saint Martin, Romain Roehrig, Christina Hsu, and Paola Formenti
Atmos. Chem. Phys., 19, 4963–4990, https://doi.org/10.5194/acp-19-4963-2019, https://doi.org/10.5194/acp-19-4963-2019, 2019
Short summary
Short summary
The model is able to represent LWP but not the LCF. AOD is consistent over the continent but also over ocean (ACAOD). Differences are observed in SSA due to the absence of internal mixing in ALADIN-Climate. A significant regional gradient of the forcing at TOA is observed. An intense positive forcing is simulated over Gabon. Results highlight the significant effect of enhanced moisture on BBA extinction. The surface dimming modifies the energy budget.
Yuekui Yang, Kerry Meyer, Galina Wind, Yaping Zhou, Alexander Marshak, Steven Platnick, Qilong Min, Anthony B. Davis, Joanna Joiner, Alexander Vasilkov, David Duda, and Wenying Su
Atmos. Meas. Tech., 12, 2019–2031, https://doi.org/10.5194/amt-12-2019-2019, https://doi.org/10.5194/amt-12-2019-2019, 2019
Short summary
Short summary
The physical basis of the EPIC cloud product algorithms and an initial evaluation of their performance are presented. EPIC cloud products include cloud mask, effective height, and optical depth. Comparison with co-located retrievals from geosynchronous earth orbit (GEO) and low earth orbit (LEO) satellites shows that the algorithms are performing well and are consistent with theoretical expectations. These products are publicly available at the NASA Langley Atmospheric Sciences Data Center.
María José Granados-Muñoz, Michael Sicard, Roberto Román, Jose Antonio Benavent-Oltra, Rubén Barragán, Gerard Brogniez, Cyrielle Denjean, Marc Mallet, Paola Formenti, Benjamín Torres, and Lucas Alados-Arboledas
Atmos. Chem. Phys., 19, 523–542, https://doi.org/10.5194/acp-19-523-2019, https://doi.org/10.5194/acp-19-523-2019, 2019
Short summary
Short summary
The influence of mineral dust in the direct radiative effect is affected by a large uncertainty. This study investigates mineral dust radiative properties during an episode affecting southern Spain in June 2013 by using remote sensors and data collected on board an aircraft to feed a radiative transfer model. The study reveals the complexity of parameterizing these models, as characterizing mineral dust is still quite challenging, and the need for accurate mineral dust measurements.
David M. Giles, Alexander Sinyuk, Mikhail G. Sorokin, Joel S. Schafer, Alexander Smirnov, Ilya Slutsker, Thomas F. Eck, Brent N. Holben, Jasper R. Lewis, James R. Campbell, Ellsworth J. Welton, Sergey V. Korkin, and Alexei I. Lyapustin
Atmos. Meas. Tech., 12, 169–209, https://doi.org/10.5194/amt-12-169-2019, https://doi.org/10.5194/amt-12-169-2019, 2019
Short summary
Short summary
Clouds or instrumental anomalies may perturb ground-based solar measurements used to calculate aerosol optical depth (AOD). This study presents a new algorithm of automated near-real-time (NRT) quality controls with improved cloud screening for AERONET AOD measurements. Results from the new and old algorithms have excellent agreement for the highest-quality AOD level, while the new algorithm provides higher-quality NRT AOD for applications such as data assimilation and satellite evaluation.
Paola Formenti, Lydie Mbemba Kabuiku, Isabelle Chiapello, Fabrice Ducos, François Dulac, and Didier Tanré
Atmos. Meas. Tech., 11, 6761–6784, https://doi.org/10.5194/amt-11-6761-2018, https://doi.org/10.5194/amt-11-6761-2018, 2018
Short summary
Short summary
Aerosol particles from natural and anthropogenic sources are climate regulators as they can counteract or amplify the warming effect of greenhouse gases, but are difficult to observe due to their temporal and spatial variability. Satellite sensors can provide the needed global coverage but need validation. In this paper we explore the capability of the POLDER-3 advanced space-borne sensor to observe aerosols over the western Mediterranean region.
Guangjie Zheng, Yang Wang, Allison C. Aiken, Francesca Gallo, Michael P. Jensen, Pavlos Kollias, Chongai Kuang, Edward Luke, Stephen Springston, Janek Uin, Robert Wood, and Jian Wang
Atmos. Chem. Phys., 18, 17615–17635, https://doi.org/10.5194/acp-18-17615-2018, https://doi.org/10.5194/acp-18-17615-2018, 2018
Short summary
Short summary
Here, we elucidate the key processes that drive marine boundary layer (MBL) aerosol size distribution in the eastern North Atlantic (ENA) using long-term measurements. The governing equations of particle concentration are established for different modes. Particles entrained from the free troposphere represent the major source of MBL cloud condensation nuclei (CCN), contributing both directly to CCN population and indirectly by supplying Aitken-mode particles that grow to CCN in the MBL.
Anna Possner, Hailong Wang, Robert Wood, Ken Caldeira, and Thomas P. Ackerman
Atmos. Chem. Phys., 18, 17475–17488, https://doi.org/10.5194/acp-18-17475-2018, https://doi.org/10.5194/acp-18-17475-2018, 2018
Short summary
Short summary
We quantify aerosol–cloud radiative interactions in a regime of deep open-cell stratocumuli (boundary layer depth 1.5 km), a regime which remains largely unexplored within this context and yet is more dominant than cases of shallow stratocumuli previously studied. We simulate substantial increases in albedo in a regime where ship tracks are not found and argue that such changes may escape detection and attribution through remote sensing due to the large natural variability in the system.
Claire L. Ryder, Franco Marenco, Jennifer K. Brooke, Victor Estelles, Richard Cotton, Paola Formenti, James B. McQuaid, Hannah C. Price, Dantong Liu, Patrick Ausset, Phil D. Rosenberg, Jonathan W. Taylor, Tom Choularton, Keith Bower, Hugh Coe, Martin Gallagher, Jonathan Crosier, Gary Lloyd, Eleanor J. Highwood, and Benjamin J. Murray
Atmos. Chem. Phys., 18, 17225–17257, https://doi.org/10.5194/acp-18-17225-2018, https://doi.org/10.5194/acp-18-17225-2018, 2018
Short summary
Short summary
Every year, millions of tons of Saharan dust particles are carried across the Atlantic by the wind, where they can affect weather patterns and climate. Their sizes span orders of magnitude, but the largest (over 10 microns – around the width of a human hair) are difficult to measure and few observations exist. Here we show new aircraft observations of large dust particles, finding more than we would expect, and we quantify their properties which allow them to interact with atmospheric radiation.
Paola Formenti, Stuart John Piketh, Andreas Namwoonde, Danitza Klopper, Roelof Burger, Mathieu Cazaunau, Anaïs Feron, Cécile Gaimoz, Stephen Broccardo, Nicola Walton, Karine Desboeufs, Guillaume Siour, Mattheus Hanghome, Samuel Mafwila, Edosa Omoregie, Wolfgang Junkermann, and Willy Maenhaut
Atmos. Chem. Phys., 18, 17003–17016, https://doi.org/10.5194/acp-18-17003-2018, https://doi.org/10.5194/acp-18-17003-2018, 2018
Short summary
Short summary
Three-years of continuous measurements at the Henties Bay Aerosol Observatory (HBAO; 22°S, 14°05’E), Namibia, show that during the austral wintertime, long- and medium-range transport of pollution from biomass and fossil fuel burning give rise to peaks of light-absorbing black carbon aerosols into the marine boundary layer ahead of the main biomass burning season. This could affect the cloud properties.
Jacob K. Hedelius, Junjie Liu, Tomohiro Oda, Shamil Maksyutov, Coleen M. Roehl, Laura T. Iraci, James R. Podolske, Patrick W. Hillyard, Jianming Liang, Kevin R. Gurney, Debra Wunch, and Paul O. Wennberg
Atmos. Chem. Phys., 18, 16271–16291, https://doi.org/10.5194/acp-18-16271-2018, https://doi.org/10.5194/acp-18-16271-2018, 2018
Short summary
Short summary
Human activities can cause concentrated emissions of greenhouse gases and other pollutants from cities. There is ongoing effort to convert new satellite observations of pollutants into fluxes for many cities. Here we present a method for determining the flux of three species (CO2, CH4, and CO) from the greater LA area using satellite (CO2 only) and ground-based (all three species) observations. We run tests to estimate uncertainty and find the direct net CO2 flux is 104 ± 26 Tg CO2 yr−1.
Dario Massabò, Silvia Giulia Danelli, Paolo Brotto, Antonio Comite, Camilla Costa, Andrea Di Cesare, Jean François Doussin, Federico Ferraro, Paola Formenti, Elena Gatta, Laura Negretti, Maddalena Oliva, Franco Parodi, Luigi Vezzulli, and Paolo Prati
Atmos. Meas. Tech., 11, 5885–5900, https://doi.org/10.5194/amt-11-5885-2018, https://doi.org/10.5194/amt-11-5885-2018, 2018
Michael S. Diamond, Amie Dobracki, Steffen Freitag, Jennifer D. Small Griswold, Ashley Heikkila, Steven G. Howell, Mary E. Kacarab, James R. Podolske, Pablo E. Saide, and Robert Wood
Atmos. Chem. Phys., 18, 14623–14636, https://doi.org/10.5194/acp-18-14623-2018, https://doi.org/10.5194/acp-18-14623-2018, 2018
Short summary
Short summary
Smoke from Africa can mix into clouds over the southeast Atlantic and create new droplets, which brightens the clouds, reflects more sunlight, and thus cools the region. Using aircraft data from a NASA field campaign, we find that cloud properties are correlated with smoke as expected when the smoke is below the clouds but not when smoke is above the clouds because it takes several days for clouds to mix smoke downward. We recommend methods that can track clouds as they move for future studies.
Carlos Toledano, Ramiro González, David Fuertes, Emilio Cuevas, Thomas F. Eck, Stelios Kazadzis, Natalia Kouremeti, Julian Gröbner, Philippe Goloub, Luc Blarel, Roberto Román, África Barreto, Alberto Berjón, Brent N. Holben, and Victoria E. Cachorro
Atmos. Chem. Phys., 18, 14555–14567, https://doi.org/10.5194/acp-18-14555-2018, https://doi.org/10.5194/acp-18-14555-2018, 2018
Short summary
Short summary
Most of the ground-based radiometric networks have their reference instruments and/or calibrate them at Mauna Loa or Izaña. The suitability of these high-mountain stations for absolute radiometric calibrations is investigated with the support of 20 years of first-class Sun photometer data from the AERONET and GAW-PFR networks. We analyze the number of calibration days at each site in a climatological sense and investigate the uncertainty of the calibrations based on long-term statistics.
Jay Herman, Elena Spinei, Alan Fried, Jhoon Kim, Jae Kim, Woogyung Kim, Alexander Cede, Nader Abuhassan, and Michal Segal-Rozenhaimer
Atmos. Meas. Tech., 11, 4583–4603, https://doi.org/10.5194/amt-11-4583-2018, https://doi.org/10.5194/amt-11-4583-2018, 2018
Short summary
Short summary
Nine Pandora Spectrometer Instruments were installed at 8 sites for KORUS-AQ (Korea U.S.-Air Quality) field study from ground, aircraft, and satellite measurements. The quantities retrieved were total column measurements of ozone, nitrogen dioxide, and formaldehyde. We show the distribution of NO2 and HCHO air pollutants vs location and time of day and comparisons with aircraft and satellite data. For some of the sites, long-term time series are available to asses changes.
Daniel P. Grosvenor, Odran Sourdeval, and Robert Wood
Atmos. Meas. Tech., 11, 4273–4289, https://doi.org/10.5194/amt-11-4273-2018, https://doi.org/10.5194/amt-11-4273-2018, 2018
Short summary
Short summary
We provide a parameterized correction to the retrieval of cloud effective radius from satellite instruments to account for the assumption that the retrieved value is representative of that at cloud top, whereas in reality it is representative of that lower down. The error leads to errors (which we quantify) in the retrieved cloud droplet concentrations of up to 38 % for stratocumulus regions and also to liquid water path errors, both of which can be corrected using our parameterizations.
Stephen Broccardo, Klaus-Peter Heue, David Walter, Christian Meyer, Alexander Kokhanovsky, Ronald van der A, Stuart Piketh, Kristy Langerman, and Ulrich Platt
Atmos. Meas. Tech., 11, 2797–2819, https://doi.org/10.5194/amt-11-2797-2018, https://doi.org/10.5194/amt-11-2797-2018, 2018
Short summary
Short summary
Measurements of nitrogen dioxide, known to originate from industrial and automotive combustion sources, have been made from space for two decades. Successive generations of instrument bring improvements in ground-pixel resolution; however features in the atmosphere are known to be smaller than what the satellites can resolve. Measurements of urban and industrial areas using a high-resolution airborne instrument allow the impact of the satellite's relatively low resolution to be evaluated.
Jungbin Mok, Nickolay A. Krotkov, Omar Torres, Hiren Jethva, Zhanqing Li, Jhoon Kim, Ja-Ho Koo, Sujung Go, Hitoshi Irie, Gordon Labow, Thomas F. Eck, Brent N. Holben, Jay Herman, Robert P. Loughman, Elena Spinei, Seoung Soo Lee, Pradeep Khatri, and Monica Campanelli
Atmos. Meas. Tech., 11, 2295–2311, https://doi.org/10.5194/amt-11-2295-2018, https://doi.org/10.5194/amt-11-2295-2018, 2018
Short summary
Short summary
Measuring aerosol absorption from the shortest ultraviolet (UV) to the near-infrared (NIR) wavelengths is important for studies of climate, tropospheric photochemistry, human health, and agricultural productivity. We estimate the accuracy and demonstrate consistency of aerosol absorption retrievals from different instruments, after accounting for spectrally varying surface albedo and gaseous absorption.
Daniela Meloni, Alcide di Sarra, Gérard Brogniez, Cyrielle Denjean, Lorenzo De Silvestri, Tatiana Di Iorio, Paola Formenti, José L. Gómez-Amo, Julian Gröbner, Natalia Kouremeti, Giuliano Liuzzi, Marc Mallet, Giandomenico Pace, and Damiano M. Sferlazzo
Atmos. Chem. Phys., 18, 4377–4401, https://doi.org/10.5194/acp-18-4377-2018, https://doi.org/10.5194/acp-18-4377-2018, 2018
Short summary
Short summary
This study examines how different aerosol optical properties determine the dust longwave radiative effects at the surface, in the atmosphere and at the top of the atmosphere, based on the combination of remote sensing and in situ observations from the ground, from airborne sensors, and from space, by means of radiative transfer modelling. The closure experiment is based on longwave irradiances and spectral brightness temperatures measured during the 2013 ChArMEx–ADRIMED campaign at Lampedusa.
Daniel T. McCoy, Frida A.-M. Bender, Daniel P. Grosvenor, Johannes K. Mohrmann, Dennis L. Hartmann, Robert Wood, and Paul R. Field
Atmos. Chem. Phys., 18, 2035–2047, https://doi.org/10.5194/acp-18-2035-2018, https://doi.org/10.5194/acp-18-2035-2018, 2018
Short summary
Short summary
The interaction between clouds and aerosols represents the largest source of uncertainty in the anthropogenic radiative forcing. Cloud droplet number concentration (CDNC) is the state variable that moderates the interaction between aerosol and clouds. Here we show that CDNC decreases off the coasts of East Asia and North America due to controls on emissions. We support this analysis through an examination of volcanism in Hawaii and Vanuatu.
Brent N. Holben, Jhoon Kim, Itaru Sano, Sonoyo Mukai, Thomas F. Eck, David M. Giles, Joel S. Schafer, Aliaksandr Sinyuk, Ilya Slutsker, Alexander Smirnov, Mikhail Sorokin, Bruce E. Anderson, Huizheng Che, Myungje Choi, James H. Crawford, Richard A. Ferrare, Michael J. Garay, Ukkyo Jeong, Mijin Kim, Woogyung Kim, Nichola Knox, Zhengqiang Li, Hwee S. Lim, Yang Liu, Hal Maring, Makiko Nakata, Kenneth E. Pickering, Stuart Piketh, Jens Redemann, Jeffrey S. Reid, Santo Salinas, Sora Seo, Fuyi Tan, Sachchida N. Tripathi, Owen B. Toon, and Qingyang Xiao
Atmos. Chem. Phys., 18, 655–671, https://doi.org/10.5194/acp-18-655-2018, https://doi.org/10.5194/acp-18-655-2018, 2018
Short summary
Short summary
Aerosol particles, such as smoke, vary over space and time. This paper describes a series of very high-resolution ground-based aerosol measurement networks and associated studies that contributed new understanding of aerosol processes and detailed comparisons to satellite aerosol validation. Significantly, these networks also provide an opportunity to statistically relate grab samples of an aerosol parameter to companion satellite observations, a step toward air quality assessment from space.
Myungje Choi, Jhoon Kim, Jaehwa Lee, Mijin Kim, Young-Je Park, Brent Holben, Thomas F. Eck, Zhengqiang Li, and Chul H. Song
Atmos. Meas. Tech., 11, 385–408, https://doi.org/10.5194/amt-11-385-2018, https://doi.org/10.5194/amt-11-385-2018, 2018
Short summary
Short summary
This study is a major version upgrade of the aerosol product from GOCI, the first and unique ocean color imager in geostationary earth orbit. It describes the improvement of version 2 of the GOCI Yonsei aerosol retrieval algorithm for near-real-time processing with improved accuracy from the modification of cloud masking, surface reflectance, etc. The product is validated against AERONET/SONET over East Asia with analyses of various errors features, and a pixel-level uncertainty is calculated.
Xiaoli Zhou, Andrew S. Ackerman, Ann M. Fridlind, Robert Wood, and Pavlos Kollias
Atmos. Chem. Phys., 17, 12725–12742, https://doi.org/10.5194/acp-17-12725-2017, https://doi.org/10.5194/acp-17-12725-2017, 2017
Short summary
Short summary
Shallow maritime clouds make a well-known transition from stratocumulus to trade cumulus with flow from the subtropics equatorward. Three-day large-eddy simulations that investigate the potential influence of overlying African biomass burning plumes during that transition indicate that cloud-related impacts are likely substantially cooling to negligible at the top of the atmosphere, with magnitude sensitive to background and perturbation aerosol and cloud properties.
Chaeyoon Cho, Sang-Woo Kim, Maheswar Rupakheti, Jin-Soo Park, Arnico Panday, Soon-Chang Yoon, Ji-Hyoung Kim, Hyunjae Kim, Haeun Jeon, Minyoung Sung, Bong Mann Kim, Seungkyu K. Hong, Rokjin J. Park, Dipesh Rupakheti, Khadak Singh Mahata, Puppala Siva Praveen, Mark G. Lawrence, and Brent Holben
Atmos. Chem. Phys., 17, 12617–12632, https://doi.org/10.5194/acp-17-12617-2017, https://doi.org/10.5194/acp-17-12617-2017, 2017
Short summary
Short summary
We investigated the optical and chemical properties and direct radiative effects of aerosols in the Kathmandu Valley. We concluded that the ratio of light-absorbing to scattering aerosols as well as the concentration of light-absorbing aerosols is much higher at Kathmandu than other comparable regions, and it contributes to a great atmospheric absorption efficiency. This study provides unprecedented insights into aerosol optical properties and their radiative forcings in the Kathmandu Valley.
Claudia Di Biagio, Paola Formenti, Mathieu Cazaunau, Edouard Pangui, Nicolas Marchand, and Jean-François Doussin
Atmos. Meas. Tech., 10, 2923–2939, https://doi.org/10.5194/amt-10-2923-2017, https://doi.org/10.5194/amt-10-2923-2017, 2017
Short summary
Short summary
Mineral dust is one of the most abundant aerosol species at the global scale and an accurate estimation of its absorption at solar wavelengths is crucial to assess its impact on climate. In this work we provide an estimate of the Aethalometer multiple scattering correction for mineral dust aerosols at 450 and 660 nm. Our results suggest that the use of an optimized correction factor can lead to up to 11 % higher absorption coefficient and to 3 % higher single scattering albedo for mineral dust.
Thomas Fauchez, Steven Platnick, Kerry Meyer, Céline Cornet, Frédéric Szczap, and Tamás Várnai
Atmos. Chem. Phys., 17, 8489–8508, https://doi.org/10.5194/acp-17-8489-2017, https://doi.org/10.5194/acp-17-8489-2017, 2017
Short summary
Short summary
This study presents impact of cirrus cloud horizontal heterogeneity on simulated thermal infrared brightness temperatures at the top of the atmosphere for spatial resolutions ranging from 50 m to 10 km. The cirrus is generated by the 3DCLOUD code and the radiative transfer by the 3DMCPOL code. Brightness temperatures are mostly impacted by the horizontal transport effect and plane-parallel bias at high and coarse spatial resolutions, respectively, with a minimum around 100 m–250 m.
Lorenzo Caponi, Paola Formenti, Dario Massabó, Claudia Di Biagio, Mathieu Cazaunau, Edouard Pangui, Servanne Chevaillier, Gautier Landrot, Meinrat O. Andreae, Konrad Kandler, Stuart Piketh, Thuraya Saeed, Dave Seibert, Earle Williams, Yves Balkanski, Paolo Prati, and Jean-François Doussin
Atmos. Chem. Phys., 17, 7175–7191, https://doi.org/10.5194/acp-17-7175-2017, https://doi.org/10.5194/acp-17-7175-2017, 2017
Short summary
Short summary
This paper presents new laboratory measurements of the shortwave mass absorption efficiency (MAE) used by climate models for mineral dust of different origin and at different sizes. We found that small particles are more efficient, by given mass, in absorbing radiation, particularly at shorter wavelength. Because dust has high concentrations in the atmosphere, light absorption by mineral dust can be competitive to other absorbing atmospheric aerosols such as black and brown carbon.
Debra Wunch, Paul O. Wennberg, Gregory Osterman, Brendan Fisher, Bret Naylor, Coleen M. Roehl, Christopher O'Dell, Lukas Mandrake, Camille Viatte, Matthäus Kiel, David W. T. Griffith, Nicholas M. Deutscher, Voltaire A. Velazco, Justus Notholt, Thorsten Warneke, Christof Petri, Martine De Maziere, Mahesh K. Sha, Ralf Sussmann, Markus Rettinger, David Pollard, John Robinson, Isamu Morino, Osamu Uchino, Frank Hase, Thomas Blumenstock, Dietrich G. Feist, Sabrina G. Arnold, Kimberly Strong, Joseph Mendonca, Rigel Kivi, Pauli Heikkinen, Laura Iraci, James Podolske, Patrick W. Hillyard, Shuji Kawakami, Manvendra K. Dubey, Harrison A. Parker, Eliezer Sepulveda, Omaira E. García, Yao Te, Pascal Jeseck, Michael R. Gunson, David Crisp, and Annmarie Eldering
Atmos. Meas. Tech., 10, 2209–2238, https://doi.org/10.5194/amt-10-2209-2017, https://doi.org/10.5194/amt-10-2209-2017, 2017
Short summary
Short summary
This paper describes the comparisons between NASA's Orbiting Carbon Observatory (OCO-2) column-averaged dry-air mole fractions of CO2 with its primary ground-based validation network, the Total Carbon Column Observing Network (TCCON). The paper shows that while the standard bias correction reduces much of the spurious variability in the satellite measurements, residual biases remain.
John Rausch, Kerry Meyer, Ralf Bennartz, and Steven Platnick
Atmos. Meas. Tech., 10, 2105–2116, https://doi.org/10.5194/amt-10-2105-2017, https://doi.org/10.5194/amt-10-2105-2017, 2017
Short summary
Short summary
This paper documents the observed differences in the aggregated (Level-3) cloud droplet effective radius and droplet number concentration estimates inferred from the Aqua–MODIS cloud product collections 5.1 and 6 for warm oceanic cloud scenes over the year 2008. We note significant differences in effective radius and droplet concentration between the two products and discuss the algorithmic and calibration changes which may contribute to observed results.
Jacob K. Hedelius, Harrison Parker, Debra Wunch, Coleen M. Roehl, Camille Viatte, Sally Newman, Geoffrey C. Toon, James R. Podolske, Patrick W. Hillyard, Laura T. Iraci, Manvendra K. Dubey, and Paul O. Wennberg
Atmos. Meas. Tech., 10, 1481–1493, https://doi.org/10.5194/amt-10-1481-2017, https://doi.org/10.5194/amt-10-1481-2017, 2017
Short summary
Short summary
Two portable spectrometers, assumed to be internally precise, were taken to four different sites with (stationary) TCCON spectrometers. Biases of column averaged CO2 and CH4 measured among the TCCON sites were estimated experimentally. Results suggest that maximum (95 % confidence interval) bias among sites is less than what was estimated from a previous analytical error analysis.
Igor B. Konovalov, Matthias Beekmann, Evgeny V. Berezin, Paola Formenti, and Meinrat O. Andreae
Atmos. Chem. Phys., 17, 4513–4537, https://doi.org/10.5194/acp-17-4513-2017, https://doi.org/10.5194/acp-17-4513-2017, 2017
Short summary
Short summary
A shortage of consistent observational evidence on biomass burning (BB) aerosol aging processes hinders the development of their adequate representations in atmospheric models. Here we show that useful insights into the BB aerosol dynamics can be obtained from analysis of satellite measurements of aerosol optical depth and carbon dioxide. Our results indicate that aging processes strongly affect the evolution of BB aerosol in smoke plumes from wildfires in Siberia.
Giuliano Liuzzi, Guido Masiello, Carmine Serio, Daniela Meloni, Claudia Di Biagio, and Paola Formenti
Atmos. Meas. Tech., 10, 599–615, https://doi.org/10.5194/amt-10-599-2017, https://doi.org/10.5194/amt-10-599-2017, 2017
Short summary
Short summary
In this work we have given a contribution to better understand some of the properties of the desert dust plumes in the western Mediterranean, using both direct measurements and satellite observations. This study has mainly evidenced that satellite observations can provide information about the geographical provenance of dust. This is important because such variability is reflected in the way in which dust interacts with atmosphere and impacts over the observed infrared radiation from satellites.
Claudia Di Biagio, Paola Formenti, Yves Balkanski, Lorenzo Caponi, Mathieu Cazaunau, Edouard Pangui, Emilie Journet, Sophie Nowak, Sandrine Caquineau, Meinrat O. Andreae, Konrad Kandler, Thuraya Saeed, Stuart Piketh, David Seibert, Earle Williams, and Jean-François Doussin
Atmos. Chem. Phys., 17, 1901–1929, https://doi.org/10.5194/acp-17-1901-2017, https://doi.org/10.5194/acp-17-1901-2017, 2017
Short summary
Short summary
Modeling the interaction of dust with long-wave (LW) radiation is still a challenge due to the scarcity of information on their refractive index. In this paper, we present a unique dataset of dust refractive indices obtained from in situ measurements in a large smog chamber. Our results show that the dust LW refractive index varies strongly from source to source due to particle composition changes. We recommend taking this variability into account in climate and remote sensing applications.
Tatiana B. Zhuravleva, Dmitriy M. Kabanov, Ilmir M. Nasrtdinov, Tatiana V. Russkova, Sergey M. Sakerin, Alexander Smirnov, and Brent N. Holben
Atmos. Meas. Tech., 10, 179–198, https://doi.org/10.5194/amt-10-179-2017, https://doi.org/10.5194/amt-10-179-2017, 2017
Short summary
Short summary
Aerosol properties were studied during a mega-fire event in summer 2012 over Siberia using ground-based measurements of spectral solar radiation at the AERONET site in Tomsk and satellite observations. The data were analysed using multi-year measurements under background conditions and yearly observed wildfires. It is shown that the aerosol radiation characteristics during individual severe fires differ significantly from the ensemble smoke hazes which are typical for the Siberian region.
Itaru Sano, Sonoyo Mukai, Makiko Nakata, and Brent N. Holben
Atmos. Chem. Phys., 16, 14795–14803, https://doi.org/10.5194/acp-16-14795-2016, https://doi.org/10.5194/acp-16-14795-2016, 2016
Short summary
Short summary
We investigated the regional and local variation of aerosols based on large and small gridded sun photometer networks. The results show that long-range transboundary aerosols strongly affect aerosol condition over Japan even at a small island in the East China Sea. A dense instrument network (DRAGON) reveals the magnitude and variation of local aerosols.
Jeffrey S. Reid, Peng Xian, Brent N. Holben, Edward J. Hyer, Elizabeth A. Reid, Santo V. Salinas, Jianglong Zhang, James R. Campbell, Boon Ning Chew, Robert E. Holz, Arunas P. Kuciauskas, Nofel Lagrosas, Derek J. Posselt, Charles R. Sampson, Annette L. Walker, E. Judd Welton, and Chidong Zhang
Atmos. Chem. Phys., 16, 14041–14056, https://doi.org/10.5194/acp-16-14041-2016, https://doi.org/10.5194/acp-16-14041-2016, 2016
Short summary
Short summary
This paper describes aspects of the 2012 7 Southeast Asian Studies (7SEAS) operations period, the largest within the Maritime Continent. Included were an enhanced deployment of Aerosol Robotic Network (AERONET) sun photometers, multiple lidars, and a Singapore supersite. Simultaneously, a ship was dispatched to the Palawan Archipelago and Sulu Sea of the Philippines for September 2012 to observe transported smoke and pollution as it entered the southwest monsoon trough.
Jeffrey S. Reid, Nofel D. Lagrosas, Haflidi H. Jonsson, Elizabeth A. Reid, Samuel A. Atwood, Thomas J. Boyd, Virendra P. Ghate, Peng Xian, Derek J. Posselt, James B. Simpas, Sherdon N. Uy, Kimo Zaiger, Donald R. Blake, Anthony Bucholtz, James R. Campbell, Boon Ning Chew, Steven S. Cliff, Brent N. Holben, Robert E. Holz, Edward J. Hyer, Sonia M. Kreidenweis, Arunas P. Kuciauskas, Simone Lolli, Min Oo, Kevin D. Perry, Santo V. Salinas, Walter R. Sessions, Alexander Smirnov, Annette L. Walker, Qing Wang, Liya Yu, Jianglong Zhang, and Yongjing Zhao
Atmos. Chem. Phys., 16, 14057–14078, https://doi.org/10.5194/acp-16-14057-2016, https://doi.org/10.5194/acp-16-14057-2016, 2016
Short summary
Short summary
This paper describes aspects of the 2012 7 Southeast Asian Studies (7SEAS) operations period, the largest within the Maritime Continent. Included were an enhanced deployment of Aerosol Robotic Network (AERONET) sun photometers, multiple lidars, and a Singapore supersite. Simultaneously, a ship was dispatched to the Palawan Archipelago and Sulu Sea of the Philippines for September 2012 to observe transported smoke and pollution as it entered the southwest monsoon trough.
Hiren Jethva, Omar Torres, Lorraine Remer, Jens Redemann, John Livingston, Stephen Dunagan, Yohei Shinozuka, Meloe Kacenelenbogen, Michal Segal Rosenheimer, and Rob Spurr
Atmos. Meas. Tech., 9, 5053–5062, https://doi.org/10.5194/amt-9-5053-2016, https://doi.org/10.5194/amt-9-5053-2016, 2016
Short summary
Short summary
Validation of the above-cloud aerosol optical depth retrieved using the "color ratio" method applied to MODIS cloudy-sky
measurements against airborne direct measurements made by NASA’s AATS and 4STAR sun photometers during SAFARI-2000,
ACE-ASIA 2001, and SEAC4RS 2013 reveals a good level of agreement (difference < 0.1), in which most matchups are found
be constrained within the estimated uncertainties associated with the MODIS retrievals (-10 % to +50 %).
Claudia Di Biagio, Paola Formenti, Lionel Doppler, Cécile Gaimoz, Noel Grand, Gerard Ancellet, Jean-Luc Attié, Silvia Bucci, Philippe Dubuisson, Federico Fierli, Marc Mallet, and François Ravetta
Atmos. Chem. Phys., 16, 10591–10607, https://doi.org/10.5194/acp-16-10591-2016, https://doi.org/10.5194/acp-16-10591-2016, 2016
Short summary
Short summary
Pollution aerosols strongly influence the composition of the Western Mediterranean, but at present little is known on their optical properties. Here, we report observations of pollution aerosols measured during the TRAQA airborne campaign in summer 2012. Data from this study indicate a large variability of the absorption for pollution particles. This variability strongly influences their direct radiative effect, with possible consequences on the hydrological cycle in this part of the basin.
Graydon Snider, Crystal L. Weagle, Kalaivani K. Murdymootoo, Amanda Ring, Yvonne Ritchie, Emily Stone, Ainsley Walsh, Clement Akoshile, Nguyen Xuan Anh, Rajasekhar Balasubramanian, Jeff Brook, Fatimah D. Qonitan, Jinlu Dong, Derek Griffith, Kebin He, Brent N. Holben, Ralph Kahn, Nofel Lagrosas, Puji Lestari, Zongwei Ma, Amit Misra, Leslie K. Norford, Eduardo J. Quel, Abdus Salam, Bret Schichtel, Lior Segev, Sachchida Tripathi, Chien Wang, Chao Yu, Qiang Zhang, Yuxuan Zhang, Michael Brauer, Aaron Cohen, Mark D. Gibson, Yang Liu, J. Vanderlei Martins, Yinon Rudich, and Randall V. Martin
Atmos. Chem. Phys., 16, 9629–9653, https://doi.org/10.5194/acp-16-9629-2016, https://doi.org/10.5194/acp-16-9629-2016, 2016
Short summary
Short summary
We examine the chemical composition of fine particulate matter (PM2.5) collected on filters at traditionally undersampled, globally dispersed urban locations. Several PM2.5 chemical components (e.g. ammonium sulfate, ammonium nitrate, and black carbon) vary by more than an order of magnitude between sites while aerosol hygroscopicity varies by a factor of 2. Enhanced anthropogenic dust fractions in large urban areas are apparent from high Zn : Al ratios.
Makoto Inoue, Isamu Morino, Osamu Uchino, Takahiro Nakatsuru, Yukio Yoshida, Tatsuya Yokota, Debra Wunch, Paul O. Wennberg, Coleen M. Roehl, David W. T. Griffith, Voltaire A. Velazco, Nicholas M. Deutscher, Thorsten Warneke, Justus Notholt, John Robinson, Vanessa Sherlock, Frank Hase, Thomas Blumenstock, Markus Rettinger, Ralf Sussmann, Esko Kyrö, Rigel Kivi, Kei Shiomi, Shuji Kawakami, Martine De Mazière, Sabrina G. Arnold, Dietrich G. Feist, Erica A. Barrow, James Barney, Manvendra Dubey, Matthias Schneider, Laura T. Iraci, James R. Podolske, Patrick W. Hillyard, Toshinobu Machida, Yousuke Sawa, Kazuhiro Tsuboi, Hidekazu Matsueda, Colm Sweeney, Pieter P. Tans, Arlyn E. Andrews, Sebastien C. Biraud, Yukio Fukuyama, Jasna V. Pittman, Eric A. Kort, and Tomoaki Tanaka
Atmos. Meas. Tech., 9, 3491–3512, https://doi.org/10.5194/amt-9-3491-2016, https://doi.org/10.5194/amt-9-3491-2016, 2016
Short summary
Short summary
In this study, we correct the biases of GOSAT XCO2 and XCH4 using TCCON data. To evaluate the effectiveness of our correction method, uncorrected/corrected GOSAT data are compared to independent XCO2 and XCH4 data derived from aircraft measurements. Consequently, we suggest that this method is effective for reducing the biases of the GOSAT data. We consider that our work provides GOSAT data users with valuable information and contributes to the further development of studies on greenhouse gases.
Kuan-Ting O and Robert Wood
Atmos. Chem. Phys., 16, 7239–7249, https://doi.org/10.5194/acp-16-7239-2016, https://doi.org/10.5194/acp-16-7239-2016, 2016
Short summary
Short summary
In this work, based on the well-known formulae of classical nucleation theory (CNT), the temperature at which the mean number of critical embryos inside a droplet is unity is derived from the Boltzmann distribution function and explored as a new simplified approximation for homogeneous freezing temperature. It thus appears that the simplicity of this approximation makes it potentially useful for predicting homogeneous freezing temperatures of water droplets in the atmosphere.
Kristina Pistone, Puppala S. Praveen, Rick M. Thomas, Veerabhadran Ramanathan, Eric M. Wilcox, and Frida A.-M. Bender
Atmos. Chem. Phys., 16, 5203–5227, https://doi.org/10.5194/acp-16-5203-2016, https://doi.org/10.5194/acp-16-5203-2016, 2016
Short summary
Short summary
A recent field campaign (CARDEX) in the northern Indian Ocean concurrently measured cloud and aerosol properties and atmospheric structure and dynamics from a ground-based observatory and unmanned aerial vehicles (UAVs). These new measurements show a correlation between highly polluted conditions and increased cloud water content, concurrent with higher atmospheric temperature and humidity. Such correlations may be of interest in future studies of the effects of pollution on cloud properties.
Kerry Meyer, Yuekui Yang, and Steven Platnick
Atmos. Meas. Tech., 9, 1785–1797, https://doi.org/10.5194/amt-9-1785-2016, https://doi.org/10.5194/amt-9-1785-2016, 2016
Short summary
Short summary
This paper presents the expected uncertainties of a single-channel cloud opacity retrieval technique and a temperature-based cloud phase approach in support of the Deep Space Climate Observatory (DSCOVR) mission; DSCOVR cloud products will be derived from Earth Polychromatic Imaging Camera (EPIC) observations. Results show that, for ice clouds, retrieval errors are minimal (< 2 %), while for liquid clouds the error is limited to within 10 %, although for thin clouds the error can be higher.
Kerry Meyer, Steven Platnick, G. Thomas Arnold, Robert E. Holz, Paolo Veglio, John Yorks, and Chenxi Wang
Atmos. Meas. Tech., 9, 1743–1753, https://doi.org/10.5194/amt-9-1743-2016, https://doi.org/10.5194/amt-9-1743-2016, 2016
Short summary
Short summary
Cirrus cloud optical and microphysical properties are retrieved from remote sensing solar reflectance measurements at two narrow wavelength channels within the broader water vapor absorption band at 1.88 µm. Results from this technique compare well with other solar reflectance, IR, and lidar-based retrievals. This approach is complementary to traditional remote sensing techniques and can extend cloud retrieval capabilities for thin cirrus clouds.
Makiko Nakata, Itaru Sano, Sonoyo Mukai, and Brent N. Holben
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-182, https://doi.org/10.5194/acp-2016-182, 2016
Revised manuscript not accepted
Short summary
Short summary
We document the spatial and temporal variations of atmospheric aerosols in East Asia, specifically focusing on the NASA/AERONET-Osaka site in March 2012 during the AERONET “DRAGON-Japan” campaign. It has been shown that airborne pollutants can influence both the local atmosphere near to their source and relatively remote locations due to long-range transportation.
Myungje Choi, Jhoon Kim, Jaehwa Lee, Mijin Kim, Young-Je Park, Ukkyo Jeong, Woogyung Kim, Hyunkee Hong, Brent Holben, Thomas F. Eck, Chul H. Song, Jae-Hyun Lim, and Chang-Keun Song
Atmos. Meas. Tech., 9, 1377–1398, https://doi.org/10.5194/amt-9-1377-2016, https://doi.org/10.5194/amt-9-1377-2016, 2016
Short summary
Short summary
The Geostationary Ocean Color Imager (GOCI) is the first ocean color sensor in geostationary orbit. It enables hourly aerosol optical properties to be observed in high spatial resolution. This study presents improvements of the GOCI Yonsei Aerosol Retrieval (YAER) algorithm and its validation results using ground-based and other satellite-based observation products during DRAGON-NE Asia 2012 Campaign. Retrieval errors are also analyzed according to various factors through the validation studies.
Anatoli Chaikovsky, Oleg Dubovik, Brent Holben, Andrey Bril, Philippe Goloub, Didier Tanré, Gelsomina Pappalardo, Ulla Wandinger, Ludmila Chaikovskaya, Sergey Denisov, Jan Grudo, Anton Lopatin, Yana Karol, Tatsiana Lapyonok, Vassilis Amiridis, Albert Ansmann, Arnoud Apituley, Lucas Allados-Arboledas, Ioannis Binietoglou, Antonella Boselli, Giuseppe D'Amico, Volker Freudenthaler, David Giles, María José Granados-Muñoz, Panayotis Kokkalis, Doina Nicolae, Sergey Oshchepkov, Alex Papayannis, Maria Rita Perrone, Alexander Pietruczuk, Francesc Rocadenbosch, Michaël Sicard, Ilya Slutsker, Camelia Talianu, Ferdinando De Tomasi, Alexandra Tsekeri, Janet Wagner, and Xuan Wang
Atmos. Meas. Tech., 9, 1181–1205, https://doi.org/10.5194/amt-9-1181-2016, https://doi.org/10.5194/amt-9-1181-2016, 2016
Short summary
Short summary
This paper presents a detailed description of LIRIC (LIdar-Radiometer Inversion Code) algorithm for simultaneous processing of coincident lidar and radiometric observations for the retrieval of the aerosol concentrations. As the lidar/radiometric input data we use measurements from European Aerosol Research Lidar Network (EARLINET) lidars and collocated sun-photometers of Aerosol Robotic Network (AERONET). The LIRIC software package was implemented and tested at a number of EARLINET stations.
Zhibo Zhang, Kerry Meyer, Hongbin Yu, Steven Platnick, Peter Colarco, Zhaoyan Liu, and Lazaros Oreopoulos
Atmos. Chem. Phys., 16, 2877–2900, https://doi.org/10.5194/acp-16-2877-2016, https://doi.org/10.5194/acp-16-2877-2016, 2016
Short summary
Short summary
The frequency of occurrence and shortwave direct radiative effects (DRE) of above-cloud aerosols (ACAs) over global oceans are investigated using 8 years of collocated CALIOP and MODIS observations. We estimated that ACAs have a global ocean annual mean diurnally averaged cloudy-sky DRE of 0.015 W m−2 (range of −0.03 to 0.06 W m−2) at TOA. The DREs at surface and within atmosphere are −0.15 W m−2 (range of −0.09 to −0.21 W m−2), and 0.17 W m−2 (range of 0.11 to 0.24 W m−2), respectively.
África Barreto, Emilio Cuevas, María-José Granados-Muñoz, Lucas Alados-Arboledas, Pedro M. Romero, Julian Gröbner, Natalia Kouremeti, Antonio F. Almansa, Tom Stone, Carlos Toledano, Roberto Román, Mikhail Sorokin, Brent Holben, Marius Canini, and Margarita Yela
Atmos. Meas. Tech., 9, 631–654, https://doi.org/10.5194/amt-9-631-2016, https://doi.org/10.5194/amt-9-631-2016, 2016
Short summary
Short summary
This paper presents the new photometer CE318-T, able to perform daytime and
night-time photometric measurements using the sun and the moon as light
sources. This new device permits a complete cycle of diurnal aerosol and water vapour measurements to be extracted, valuable to enhance atmospheric monitoring. We have also highlighted the ability of this new device to capture short-term atmospheric variations, critical for climate studies.
M. Kim, J. Kim, U. Jeong, W. Kim, H. Hong, B. Holben, T. F. Eck, J. H. Lim, C. K. Song, S. Lee, and C.-Y. Chung
Atmos. Chem. Phys., 16, 1789–1808, https://doi.org/10.5194/acp-16-1789-2016, https://doi.org/10.5194/acp-16-1789-2016, 2016
Short summary
Short summary
An aerosol model optimized for East Asia is improved by applying inversion data from the DRAGON-NE Asia 2012 campaign, and is applied to an AOD retrieval algorithm using single visible measurements from a GEO satellite. In sensitivity tests, a 4 % overestimation in SSA can cause an underestimation in AOD of over 20 %. In accordance with the test, the overestimating tendency of AOD was improved by 8 % after the modification of the aerosol model.
G. L. Schuster, O. Dubovik, A. Arola, T. F. Eck, and B. N. Holben
Atmos. Chem. Phys., 16, 1587–1602, https://doi.org/10.5194/acp-16-1587-2016, https://doi.org/10.5194/acp-16-1587-2016, 2016
Short summary
Short summary
Some authors have recently suggested that the spectral dependence of aerosol absorption may be used to separate soot carbon absorption from the aerosol absorption associated with organic carbon and dust. We demonstrate that this approach is inconsistent with the underlying assumptions that are required to infer aerosol absorption through remote sensing techniques, and that carbonaceous aerosols can not be differentiated from dust by exclusively using spectral absorption signatures.
S. Mailler, L. Menut, A. G. di Sarra, S. Becagli, T. Di Iorio, B. Bessagnet, R. Briant, P. Formenti, J.-F. Doussin, J. L. Gómez-Amo, M. Mallet, G. Rea, G. Siour, D. M. Sferlazzo, R. Traversi, R. Udisti, and S. Turquety
Atmos. Chem. Phys., 16, 1219–1244, https://doi.org/10.5194/acp-16-1219-2016, https://doi.org/10.5194/acp-16-1219-2016, 2016
Short summary
Short summary
We studied the impact of aerosols on tropospheric photolysis rates at Lampedusa during the CharMEx/ADRIMED campaign in June 2013. It is shown by using the CHIMERE chemistry-transport model (CTM) as well as in situ and remote-sensing measurements that taking into account the radiative effect of the tropospheric aerosols improves the ability of the model to reproduce the observed photolysis rates. It is hence important for CTMs to include the radiative effect of aerosols on photochemistry.
Q. Xiao, H. Zhang, M. Choi, S. Li, S. Kondragunta, J. Kim, B. Holben, R. C. Levy, and Y. Liu
Atmos. Chem. Phys., 16, 1255–1269, https://doi.org/10.5194/acp-16-1255-2016, https://doi.org/10.5194/acp-16-1255-2016, 2016
Short summary
Short summary
Using ground AOD measurements from AERONET, DRAGON-Asia Campaign, and handheld sunphotometers, we evaluated emerging aerosol products from VIIRS, GOCI, and Terra and Aqua MODIS (Collection 6) in East Asia in 2012–2013. We found that satellite aerosol products performed better in tracking the day-to-day variability than the high-resolution spatial variability. VIIRS EDR and GOCI products provided the most accurate AOD retrievals, while VIIRS IP and MODIS C6 3 km products had positive biases.
C. Denjean, F. Cassola, A. Mazzino, S. Triquet, S. Chevaillier, N. Grand, T. Bourrianne, G. Momboisse, K. Sellegri, A. Schwarzenbock, E. Freney, M. Mallet, and P. Formenti
Atmos. Chem. Phys., 16, 1081–1104, https://doi.org/10.5194/acp-16-1081-2016, https://doi.org/10.5194/acp-16-1081-2016, 2016
Short summary
Short summary
This study investigates the size distribution, chemical composition, and optical properties of Saharan mineral dust transported over the western Mediterranean using in situ measurements collected from aircraft. Their variability due to altitude, time of transport, and mixing rate with pollution particles are discussed. We found moderate light absorption of the dust plumes even in the presence of pollution particles and the persistence of large dust particles after transport in the Mediterranean.
M. Mallet, F. Dulac, P. Formenti, P. Nabat, J. Sciare, G. Roberts, J. Pelon, G. Ancellet, D. Tanré, F. Parol, C. Denjean, G. Brogniez, A. di Sarra, L. Alados-Arboledas, J. Arndt, F. Auriol, L. Blarel, T. Bourrianne, P. Chazette, S. Chevaillier, M. Claeys, B. D'Anna, Y. Derimian, K. Desboeufs, T. Di Iorio, J.-F. Doussin, P. Durand, A. Féron, E. Freney, C. Gaimoz, P. Goloub, J. L. Gómez-Amo, M. J. Granados-Muñoz, N. Grand, E. Hamonou, I. Jankowiak, M. Jeannot, J.-F. Léon, M. Maillé, S. Mailler, D. Meloni, L. Menut, G. Momboisse, J. Nicolas, T. Podvin, V. Pont, G. Rea, J.-B. Renard, L. Roblou, K. Schepanski, A. Schwarzenboeck, K. Sellegri, M. Sicard, F. Solmon, S. Somot, B Torres, J. Totems, S. Triquet, N. Verdier, C. Verwaerde, F. Waquet, J. Wenger, and P. Zapf
Atmos. Chem. Phys., 16, 455–504, https://doi.org/10.5194/acp-16-455-2016, https://doi.org/10.5194/acp-16-455-2016, 2016
Short summary
Short summary
The aim of this article is to present an experimental campaign over the Mediterranean focused on aerosol-radiation measurements and modeling. Results indicate an important atmospheric loading associated with a moderate absorbing ability of mineral dust. Observations suggest a complex vertical structure and size distributions characterized by large aerosols within dust plumes. The radiative effect is highly variable, with negative forcing over the Mediterranean and positive over northern Africa.
M. S. Norgren, J. D. Small, H. H. Jonsson, and P. Y. Chuang
Atmos. Chem. Phys., 16, 21–33, https://doi.org/10.5194/acp-16-21-2016, https://doi.org/10.5194/acp-16-21-2016, 2016
Short summary
Short summary
Clouds transport air from near the surface to higher altitudes. However, the amount of air transported in this way is poorly understood. In this study, measurements from aircraft of small clouds over Texas show that the amount is limited to the volume of the visible cloud and not more. This means that these clouds are not very effective at transporting pollution and moisture to upper reaches of the atmosphere, which in turn affects their redistribution and wider impact.
C. Di Biagio, L. Doppler, C. Gaimoz, N. Grand, G. Ancellet, J.-C. Raut, M. Beekmann, A. Borbon, K. Sartelet, J.-L. Attié, F. Ravetta, and P. Formenti
Atmos. Chem. Phys., 15, 9611–9630, https://doi.org/10.5194/acp-15-9611-2015, https://doi.org/10.5194/acp-15-9611-2015, 2015
Short summary
Short summary
Observations from this study indicate that continental pollution largely affects the atmospheric composition and structure of the western Mediterranean basin. Pollution plumes reach 3000-4000 m in altitude and present a very complex and highly stratified structure, characterized by fresh and aged layers both in the boundary layer and in the free troposphere. Also we report the observations of high levels of ultrafine particles over the basin, possibly linked to new particle formation events.
C. L. Ryder, J. B. McQuaid, C. Flamant, P. D. Rosenberg, R. Washington, H. E. Brindley, E. J. Highwood, J. H. Marsham, D. J. Parker, M. C. Todd, J. R. Banks, J. K. Brooke, S. Engelstaedter, V. Estelles, P. Formenti, L. Garcia-Carreras, C. Kocha, F. Marenco, H. Sodemann, C. J. T. Allen, A. Bourdon, M. Bart, C. Cavazos-Guerra, S. Chevaillier, J. Crosier, E. Darbyshire, A. R. Dean, J. R. Dorsey, J. Kent, D. O'Sullivan, K. Schepanski, K. Szpek, J. Trembath, and A. Woolley
Atmos. Chem. Phys., 15, 8479–8520, https://doi.org/10.5194/acp-15-8479-2015, https://doi.org/10.5194/acp-15-8479-2015, 2015
Short summary
Short summary
Measurements of the Saharan atmosphere and of atmospheric mineral dust are lacking but are vital to our understanding of the climate of this region and their impacts further afield. Novel observations were made by the Fennec climate programme during June 2011 and 2012 using ground-based, remote sensing and airborne platforms. Here we describe the airborne observations and the contributions they have made to furthering our understanding of the Saharan climate system.
Y. Shinozuka, A. D. Clarke, A. Nenes, A. Jefferson, R. Wood, C. S. McNaughton, J. Ström, P. Tunved, J. Redemann, K. L. Thornhill, R. H. Moore, T. L. Lathem, J. J. Lin, and Y. J. Yoon
Atmos. Chem. Phys., 15, 7585–7604, https://doi.org/10.5194/acp-15-7585-2015, https://doi.org/10.5194/acp-15-7585-2015, 2015
L. Menut, S. Mailler, G. Siour, B. Bessagnet, S. Turquety, G. Rea, R. Briant, M. Mallet, J. Sciare, P. Formenti, and F. Meleux
Atmos. Chem. Phys., 15, 6159–6182, https://doi.org/10.5194/acp-15-6159-2015, https://doi.org/10.5194/acp-15-6159-2015, 2015
Short summary
Short summary
The ozone and aerosol concentration variability is studied over the Euro-Mediterranean area during the months of June and July 2013 and in the framework of the ADRIMED project. A first analysis is performed using meteorological variables, ozone and aerosol concentrations using routine network station, satellite and specific ADRIMED project airborne measurements. This analysis is complemented by modeling using the WRF and CHIMERE regional models.
C. Denjean, P. Formenti, B. Picquet-Varrault, E. Pangui, P. Zapf, Y. Katrib, C. Giorio, A. Tapparo, A. Monod, B. Temime-Roussel, P. Decorse, C. Mangeney, and J. F. Doussin
Atmos. Chem. Phys., 15, 3339–3358, https://doi.org/10.5194/acp-15-3339-2015, https://doi.org/10.5194/acp-15-3339-2015, 2015
P. Nabat, S. Somot, M. Mallet, M. Michou, F. Sevault, F. Driouech, D. Meloni, A. di Sarra, C. Di Biagio, P. Formenti, M. Sicard, J.-F. Léon, and M.-N. Bouin
Atmos. Chem. Phys., 15, 3303–3326, https://doi.org/10.5194/acp-15-3303-2015, https://doi.org/10.5194/acp-15-3303-2015, 2015
Short summary
Short summary
This paper uses an original approach based on a coupled regional aerosol--atmosphere--ocean model to study the dust radiative effects over the Mediterranean in summer 2012. After an evaluation of the prognostic aerosol scheme, the dust aerosol daily variability is shown to improve the simulated surface radiation and temperature at the daily scale. It has also a significant impact on the summer average, thus highlighting the importance of a relevant representation of aerosols in climate models.
K. Knobelspiesse, B. van Diedenhoven, A. Marshak, S. Dunagan, B. Holben, and I. Slutsker
Atmos. Meas. Tech., 8, 1537–1554, https://doi.org/10.5194/amt-8-1537-2015, https://doi.org/10.5194/amt-8-1537-2015, 2015
Short summary
Short summary
We test if ground-based sun photometers/radiometers like those in the Aerosol Robotic Network (AERONET) can use the polarization sensitivity of some instruments for improved cloud optical property retrieval. Our radiative transfer simulations show that the direction of linear polarization indicates cloud thermodynamic phase for optically thin clouds. In practice, data analysis shows a weak response with AERONET instruments, most likely due to noise and orientation/calibration ambiguity.
S. E. LeBlanc, P. Pilewskie, K. S. Schmidt, and O. Coddington
Atmos. Meas. Tech., 8, 1361–1383, https://doi.org/10.5194/amt-8-1361-2015, https://doi.org/10.5194/amt-8-1361-2015, 2015
Short summary
Short summary
Cloud properties are obtained via transmitted light that has interacted with cloud particles throughout its vertical extent. To achieve this, we introduce a new retrieval based on spectrally resolved measurements. We used 15 parameters to quantify spectral features in transmitted light modulated by cloud optical thickness, effective radius, and thermodynamic phase. When applied to ground-based measurements, this method results in a closer match to measured spectra than two other methods.
T. Fauchez, P. Dubuisson, C. Cornet, F. Szczap, A. Garnier, J. Pelon, and K. Meyer
Atmos. Meas. Tech., 8, 633–647, https://doi.org/10.5194/amt-8-633-2015, https://doi.org/10.5194/amt-8-633-2015, 2015
C. Denjean, P. Formenti, B. Picquet-Varrault, M. Camredon, E. Pangui, P. Zapf, Y. Katrib, C. Giorio, A. Tapparo, B. Temime-Roussel, A. Monod, B. Aumont, and J. F. Doussin
Atmos. Chem. Phys., 15, 883–897, https://doi.org/10.5194/acp-15-883-2015, https://doi.org/10.5194/acp-15-883-2015, 2015
C. Di Biagio, H. Boucher, S. Caquineau, S. Chevaillier, J. Cuesta, and P. Formenti
Atmos. Chem. Phys., 14, 11093–11116, https://doi.org/10.5194/acp-14-11093-2014, https://doi.org/10.5194/acp-14-11093-2014, 2014
P. Formenti, S. Caquineau, K. Desboeufs, A. Klaver, S. Chevaillier, E. Journet, and J. L. Rajot
Atmos. Chem. Phys., 14, 10663–10686, https://doi.org/10.5194/acp-14-10663-2014, https://doi.org/10.5194/acp-14-10663-2014, 2014
E. Kassianov, J. Barnard, M. Pekour, L. K. Berg, J. Shilling, C. Flynn, F. Mei, and A. Jefferson
Atmos. Meas. Tech., 7, 3247–3261, https://doi.org/10.5194/amt-7-3247-2014, https://doi.org/10.5194/amt-7-3247-2014, 2014
L. Menut, S. Mailler, G. Siour, B. Bessagnet, S. Turquety, G. Rea, R. Briant, M. Mallet, J. Sciare, and P. Formenti
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-14-23075-2014, https://doi.org/10.5194/acpd-14-23075-2014, 2014
Revised manuscript not accepted
C. R. Terai, C. S. Bretherton, R. Wood, and G. Painter
Atmos. Chem. Phys., 14, 8071–8088, https://doi.org/10.5194/acp-14-8071-2014, https://doi.org/10.5194/acp-14-8071-2014, 2014
D. P. Grosvenor and R. Wood
Atmos. Chem. Phys., 14, 7291–7321, https://doi.org/10.5194/acp-14-7291-2014, https://doi.org/10.5194/acp-14-7291-2014, 2014
A. Muhlbauer, I. L. McCoy, and R. Wood
Atmos. Chem. Phys., 14, 6695–6716, https://doi.org/10.5194/acp-14-6695-2014, https://doi.org/10.5194/acp-14-6695-2014, 2014
S. G. Howell, A. D. Clarke, S. Freitag, C. S. McNaughton, V. Kapustin, V. Brekovskikh, J.-L. Jimenez, and M. J. Cubison
Atmos. Chem. Phys., 14, 5073–5087, https://doi.org/10.5194/acp-14-5073-2014, https://doi.org/10.5194/acp-14-5073-2014, 2014
J. M. Livingston, J. Redemann, Y. Shinozuka, R. Johnson, P. B. Russell, Q. Zhang, S. Mattoo, L. Remer, R. Levy, L. Munchak, and S. Ramachandran
Atmos. Chem. Phys., 14, 2015–2038, https://doi.org/10.5194/acp-14-2015-2014, https://doi.org/10.5194/acp-14-2015-2014, 2014
C. Denjean, P. Formenti, B. Picquet-Varrault, Y. Katrib, E. Pangui, P. Zapf, and J. F. Doussin
Atmos. Meas. Tech., 7, 183–197, https://doi.org/10.5194/amt-7-183-2014, https://doi.org/10.5194/amt-7-183-2014, 2014
S. Freitag, A. D. Clarke, S. G. Howell, V. N. Kapustin, T. Campos, V. L. Brekhovskikh, and J. Zhou
Atmos. Meas. Tech., 7, 107–128, https://doi.org/10.5194/amt-7-107-2014, https://doi.org/10.5194/amt-7-107-2014, 2014
A. H. Berner, C. S. Bretherton, R. Wood, and A. Muhlbauer
Atmos. Chem. Phys., 13, 12549–12572, https://doi.org/10.5194/acp-13-12549-2013, https://doi.org/10.5194/acp-13-12549-2013, 2013
C. R. Terai and R. Wood
Atmos. Chem. Phys., 13, 9899–9914, https://doi.org/10.5194/acp-13-9899-2013, https://doi.org/10.5194/acp-13-9899-2013, 2013
A. Gettelman, H. Morrison, C. R. Terai, and R. Wood
Atmos. Chem. Phys., 13, 9855–9867, https://doi.org/10.5194/acp-13-9855-2013, https://doi.org/10.5194/acp-13-9855-2013, 2013
A. D. Clarke, S. Freitag, R. M. C. Simpson, J. G. Hudson, S. G. Howell, V. L. Brekhovskikh, T. Campos, V. N. Kapustin, and J. Zhou
Atmos. Chem. Phys., 13, 7511–7529, https://doi.org/10.5194/acp-13-7511-2013, https://doi.org/10.5194/acp-13-7511-2013, 2013
R. Blot, A. D. Clarke, S. Freitag, V. Kapustin, S. G. Howell, J. B. Jensen, L. M. Shank, C. S. McNaughton, and V. Brekhovskikh
Atmos. Chem. Phys., 13, 7263–7278, https://doi.org/10.5194/acp-13-7263-2013, https://doi.org/10.5194/acp-13-7263-2013, 2013
R. C. George, R. Wood, C. S. Bretherton, and G. Painter
Atmos. Chem. Phys., 13, 6305–6328, https://doi.org/10.5194/acp-13-6305-2013, https://doi.org/10.5194/acp-13-6305-2013, 2013
A. Waked, C. Seigneur, F. Couvidat, Y. Kim, K. Sartelet, C. Afif, A. Borbon, P. Formenti, and S. Sauvage
Atmos. Chem. Phys., 13, 5873–5886, https://doi.org/10.5194/acp-13-5873-2013, https://doi.org/10.5194/acp-13-5873-2013, 2013
C. H. Twohy, J. R. Anderson, D. W. Toohey, M. Andrejczuk, A. Adams, M. Lytle, R. C. George, R. Wood, P. Saide, S. Spak, P. Zuidema, and D. Leon
Atmos. Chem. Phys., 13, 2541–2562, https://doi.org/10.5194/acp-13-2541-2013, https://doi.org/10.5194/acp-13-2541-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
The impact of cloudiness and cloud type on the atmospheric heating rate of black and brown carbon in the Po Valley
Meteorology-driven variability of air pollution (PM1) revealed with explainable machine learning
The seasonal cycle of ice-nucleating particles linked to the abundance of biogenic aerosol in boreal forests
Measurement report: Cloud processes and the transport of biological emissions affect southern ocean particle and cloud condensation nuclei concentrations
Effects of marine fuel sulfur restrictions on particle number concentrations and size distributions in ship plumes in the Baltic Sea
Elemental and water-insoluble organic carbon in Svalbard snow: a synthesis of observations during 2007–2018
Deposition of light-absorbing particles in glacier snow of the Sunderdhunga Valley, the southern forefront of the central Himalayas
Influence of vegetation on occurrence and time distributions of regional new aerosol particle formation and growth
Dominant synoptic patterns associated with the decay process of PM2.5 pollution episodes around Beijing
Validation of aerosol backscatter profiles from Raman lidar and ceilometer using balloon-borne measurements
Impacts of coagulation on the appearance time method for new particle growth rate evaluation and their corrections
PM2.5 surface concentrations in southern West African urban areas based on sun photometer and satellite observations
Observations on aerosol optical properties and scavenging during cloud events
Assessing the vertical structure of Arctic aerosols using balloon-borne measurements
An overview of the ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) project: aerosol–cloud–radiation interactions in the southeast Atlantic basin
Measurement report: aerosol hygroscopic properties extended to 600 nm in the urban environment
Spatiotemporal variation and trends in equivalent black carbon in the Helsinki metropolitan area in Finland
Characteristics of sub-10 nm particle emissions from in-use commercial aircraft observed at Narita International Airport
The CLoud–Aerosol–Radiation Interaction and Forcing: Year 2017 (CLARIFY-2017) measurement campaign
Measurement report: quantifying source contribution of fossil fuels and biomass-burning black carbon aerosol in the southeastern margin of the Tibetan Plateau
The electrical activity of Saharan dust as perceived from surface electric field observations
Long-term measurement of sub-3 nm particles and their precursor gases in the boreal forest
Variability in the mass absorption cross section of black carbon (BC) aerosols is driven by BC internal mixing state at a central European background site (Melpitz, Germany) in winter
Optical and hygroscopic properties of black carbon influenced by particle microphysics at the top of the anthropogenically polluted boundary layer
Measurement report: Properties of aerosol and gases in the vertical profile during the LAPSE-RATE campaign
Aircraft vertical profiles during summertime regional and Saharan dust scenarios over the north-western Mediterranean basin: aerosol optical and physical properties
African dust particles over the western Caribbean – Part I: Impact on air quality over the Yucatán Peninsula
Direct measurements of black carbon fluxes in central Beijing using the eddy covariance method
Measurements to determine the mixing state of black carbon emitted from the 2017–2018 California wildfires and urban Los Angeles
What can we learn about urban air quality with regard to the first outbreak of the COVID-19 pandemic? A case study from central Europe
The important roles of surface tension and growth rate in the contribution of new particle formation (NPF) to cloud condensation nuclei (CCN) number concentration: evidence from field measurements in southern China
Measurement report: Source and mixing state of black carbon aerosol in the North China Plain: implications for radiative effect
The potential role of organics in new particle formation and initial growth in the remote tropical upper troposphere
Impacts of long-range transport of aerosols on marine-boundary-layer clouds in the eastern North Atlantic
Quantifying bioaerosol concentrations in dust clouds through online UV-LIF and mass spectrometry measurements at the Cape Verde Atmospheric Observatory
New particle formation at urban and high-altitude remote sites in the south-eastern Iberian Peninsula
Complex refractive indices in the ultraviolet and visible spectral region for highly absorbing non-spherical biomass burning aerosol
Characterization of submicron organic particles in Beijing during summertime: comparison between SP-AMS and HR-AMS
The characterization of Taklamakan dust properties using a multiwavelength Raman polarization lidar in Kashi, China
From a polar to a marine environment: has the changing Arctic led to a shift in aerosol light scattering properties?
Atmospheric new particle formation characteristics in the Arctic as measured at Mount Zeppelin, Svalbard, from 2016 to 2018
Rapid evolution of aerosol particles and their optical properties downwind of wildfires in the western US
Distinct aerosol effects on cloud-to-ground lightning in the plateau and basin regions of Sichuan, Southwest China
Spatial and temporal representativeness of point measurements for nitrogen dioxide pollution levels in cities
Measurement report: Balloon-borne in-situ profiling of Saharan dust over Cyprus with the UCASS optical particle counter
Vertical variability of the properties of highly aged biomass burning aerosol transported over the southeast Atlantic during CLARIFY-2017
Large contribution of organics to condensational growth and formation of cloud condensation nuclei (CCN) in the remote marine boundary layer
ENSO Effect on Interannual Variability of Spring Aerosols over East Asia
Decennial time trends and diurnal patterns of particle number concentrations in a central European city between 2008 and 2018
Roles of climate variability on the rapid increases of early winter haze pollution in North China after 2010
Luca Ferrero, Asta Gregorič, Griša Močnik, Martin Rigler, Sergio Cogliati, Francesca Barnaba, Luca Di Liberto, Gian Paolo Gobbi, Niccolò Losi, and Ezio Bolzacchini
Atmos. Chem. Phys., 21, 4869–4897, https://doi.org/10.5194/acp-21-4869-2021, https://doi.org/10.5194/acp-21-4869-2021, 2021
Short summary
Short summary
The work experimentally quantifies the impact of cloudiness and cloud type on the atmospheric heating rate of black and brown carbon. The most impacting clouds were stratocumulus, altostratus and stratus. Clouds caused a decrease of the heating rate of about 12 % per okta. The black carbon decease was slightly higher with respect to that of brown carbon. This study highlights the need to take into account the role of cloudiness when modelling light-absorbing aerosol climate forcing.
Roland Stirnberg, Jan Cermak, Simone Kotthaus, Martial Haeffelin, Hendrik Andersen, Julia Fuchs, Miae Kim, Jean-Eudes Petit, and Olivier Favez
Atmos. Chem. Phys., 21, 3919–3948, https://doi.org/10.5194/acp-21-3919-2021, https://doi.org/10.5194/acp-21-3919-2021, 2021
Short summary
Short summary
Air pollution endangers human health and poses a problem particularly in densely populated areas. Here, an explainable machine learning approach is used to analyse periods of high particle concentrations for a suburban site southwest of Paris to better understand its atmospheric drivers. Air pollution is particularly excaberated by low temperatures and low mixed layer heights, but processes vary substantially between and within seasons.
Julia Schneider, Kristina Höhler, Paavo Heikkilä, Jorma Keskinen, Barbara Bertozzi, Pia Bogert, Tobias Schorr, Nsikanabasi Silas Umo, Franziska Vogel, Zoé Brasseur, Yusheng Wu, Simo Hakala, Jonathan Duplissy, Dmitri Moisseev, Markku Kulmala, Michael P. Adams, Benjamin J. Murray, Kimmo Korhonen, Liqing Hao, Erik S. Thomson, Dimitri Castarède, Thomas Leisner, Tuukka Petäjä, and Ottmar Möhler
Atmos. Chem. Phys., 21, 3899–3918, https://doi.org/10.5194/acp-21-3899-2021, https://doi.org/10.5194/acp-21-3899-2021, 2021
Short summary
Short summary
By triggering the formation of ice crystals, ice-nucleating particles (INP) strongly influence cloud formation. Continuous, long-term measurements are needed to characterize the atmospheric INP variability. Here, a first long-term time series of INP spectra measured in the boreal forest for more than 1 year is presented, showing a clear seasonal cycle. It is shown that the seasonal dependency of INP concentrations and prevalent INP types is driven by the abundance of biogenic aerosol.
Kevin J. Sanchez, Gregory C. Roberts, Georges Saliba, Lynn M. Russell, Cynthia Twohy, J. Michael Reeves, Ruhi S. Humphries, Melita D. Keywood, Jason P. Ward, and Ian M. McRobert
Atmos. Chem. Phys., 21, 3427–3446, https://doi.org/10.5194/acp-21-3427-2021, https://doi.org/10.5194/acp-21-3427-2021, 2021
Short summary
Short summary
Measurements of particles and their properties were made from aircraft over the Southern Ocean. Aerosol transported from the Antarctic coast is shown to greatly enhance particle concentrations over the Southern Ocean. The occurrence of precipitation was shown to be associated with the lowest particle concentrations over the Southern Ocean. These particles are important due to their ability to enhance cloud droplet concentrations, resulting in more sunlight being reflected by the clouds.
Sami D. Seppälä, Joel Kuula, Antti-Pekka Hyvärinen, Sanna Saarikoski, Topi Rönkkö, Jorma Keskinen, Jukka-Pekka Jalkanen, and Hilkka Timonen
Atmos. Chem. Phys., 21, 3215–3234, https://doi.org/10.5194/acp-21-3215-2021, https://doi.org/10.5194/acp-21-3215-2021, 2021
Short summary
Short summary
The effects of fuel sulfur content restrictions implemented by the International Maritime Organization in the Baltic Sea (in July 2010 and January 2015) on the particle properties of ship exhaust plumes and ambient aerosol were studied. The restrictions reduced the particle number concentrations and median particle size in plumes and number concentrations in ambient aerosol. These changes may improve human health in coastal areas and decrease the cooling effect of exhaust emissions from ships.
Christian Zdanowicz, Jean-Charles Gallet, Mats P. Björkman, Catherine Larose, Thomas Schuler, Bartłomiej Luks, Krystyna Koziol, Andrea Spolaor, Elena Barbaro, Tõnu Martma, Ward van Pelt, Ulla Wideqvist, and Johan Ström
Atmos. Chem. Phys., 21, 3035–3057, https://doi.org/10.5194/acp-21-3035-2021, https://doi.org/10.5194/acp-21-3035-2021, 2021
Short summary
Short summary
Black carbon (BC) aerosols are soot-like particles which, when transported to the Arctic, darken snow surfaces, thus indirectly affecting climate. Information on BC in Arctic snow is needed to measure their impact and monitor the efficacy of pollution-reduction policies. This paper presents a large new set of BC measurements in snow in Svalbard collected between 2007 and 2018. It describes how BC in snow varies across the archipelago and explores some factors controlling these variations.
Jonas Svensson, Johan Ström, Henri Honkanen, Eija Asmi, Nathaniel B. Dkhar, Shresth Tayal, Ved P. Sharma, Rakesh Hooda, Matti Leppäranta, Hans-Werner Jacobi, Heikki Lihavainen, and Antti Hyvärinen
Atmos. Chem. Phys., 21, 2931–2943, https://doi.org/10.5194/acp-21-2931-2021, https://doi.org/10.5194/acp-21-2931-2021, 2021
Short summary
Short summary
Light-absorbing particles specifically affect snowmelt in the Himalayas. Through measurements of the constituents in glacier snow pits from the Indian Himalayas our investigations show that different snow layers display striking similarities. These similarities can be characterized by a deposition constant. Our results further indicate that mineral dust can be responsible for the majority of light absorption in the snow in this part of the Himalayas.
Imre Salma, Wanda Thén, Pasi Aalto, Veli-Matti Kerminen, Anikó Kern, Zoltán Barcza, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 21, 2861–2880, https://doi.org/10.5194/acp-21-2861-2021, https://doi.org/10.5194/acp-21-2861-2021, 2021
Short summary
Short summary
The distribution of the monthly mean nucleation frequency possessed a characteristic pattern. Its shape was compared to those of environmental variables, including vegetation-derived properties. The spring maximum in the occurrence frequency often overlapped with the positive T anomaly. The link between the heat stress and the occurrence minimum in summer could not be proven, whereas an association between the occurrence frequency and vegetation growth dynamics was clearly identified in spring.
Xiaoyan Wang, Renhe Zhang, Yanke Tan, and Wei Yu
Atmos. Chem. Phys., 21, 2491–2508, https://doi.org/10.5194/acp-21-2491-2021, https://doi.org/10.5194/acp-21-2491-2021, 2021
Short summary
Short summary
The physical mechanisms of synoptic patterns affecting the decay process of air pollution episodes are investigated in this work. Three dominant circulation patterns are identified, which usually decrease the ambient PM2.5 concentrations by 27%–41% after they arrive around Beijing. Emission reductions led to a 4.3–5.7 μg (m3 yr-1)-1 decrease in PM2.5 concentrations around Beijing during 2014 to 2020.
Simone Brunamonti, Giovanni Martucci, Gonzague Romanens, Yann Poltera, Frank G. Wienhold, Maxime Hervo, Alexander Haefele, and Francisco Navas-Guzmán
Atmos. Chem. Phys., 21, 2267–2285, https://doi.org/10.5194/acp-21-2267-2021, https://doi.org/10.5194/acp-21-2267-2021, 2021
Short summary
Short summary
Lidar (light detection and ranging) is a class of remote-sensing instruments that are widely used for the monitoring of aerosol properties in the lower levels of the atmosphere, yet their measurements are affected by several sources of uncertainty. Here we present the first comparison of two lidar systems against a fully independent instrument carried by meteorological balloons. We show that both lidars achieve a good agreement with the high-precision balloon measurements up to 6 km altitude.
Runlong Cai, Chenxi Li, Xu-Cheng He, Chenjuan Deng, Yiqun Lu, Rujing Yin, Chao Yan, Lin Wang, Jingkun Jiang, Markku Kulmala, and Juha Kangasluoma
Atmos. Chem. Phys., 21, 2287–2304, https://doi.org/10.5194/acp-21-2287-2021, https://doi.org/10.5194/acp-21-2287-2021, 2021
Short summary
Short summary
Growth rate determines the survival probability of atmospheric new particles and hence their impacts. We clarify the impacts of coagulation on the values retrieved by the appearance time method, which is widely used for growth rate evaluation. A new formula with coagulation correction is proposed based on derivation and tested using both models and atmospheric data. We show that the sub-3 nm particle growth rate in polluted environments may be overestimated without the coagulation correction.
Jean-François Léon, Aristide Barthélémy Akpo, Mouhamadou Bedou, Julien Djossou, Marleine Bodjrenou, Véronique Yoboué, and Cathy Liousse
Atmos. Chem. Phys., 21, 1815–1834, https://doi.org/10.5194/acp-21-1815-2021, https://doi.org/10.5194/acp-21-1815-2021, 2021
Short summary
Short summary
We have investigated the aerosol optical depth (AOD) and its relation to PM2.5 surface concentrations in southern West Africa based on in situ observations (2015–2017 period) and MODIS satellite data (2003–2019). MODIS AODs are validated using a regional network of handheld and automatic sun photometers. Satellite-derived PM2.5 shows an increasing trend during the short dry period that is possibly linked to the increase in anthropogenic emission over this area.
Antti Ruuskanen, Sami Romakkaniemi, Harri Kokkola, Antti Arola, Santtu Mikkonen, Harri Portin, Annele Virtanen, Kari E. J. Lehtinen, Mika Komppula, and Ari Leskinen
Atmos. Chem. Phys., 21, 1683–1695, https://doi.org/10.5194/acp-21-1683-2021, https://doi.org/10.5194/acp-21-1683-2021, 2021
Short summary
Short summary
The study focuses mainly on cloud-scavenging efficiency of absorbing particulate matter (mainly black carbon) but additionally covers cloud-scavenging efficiency of scattering particles and statistics of cloud condensation nuclei. The main findings give insight into how black carbon is distributed in different particle sizes and the sensitivity to cloud scavenged. The main findings are useful for large-scale modelling for evaluating cloud scavenging.
Jessie M. Creamean, Gijs de Boer, Hagen Telg, Fan Mei, Darielle Dexheimer, Matthew D. Shupe, Amy Solomon, and Allison McComiskey
Atmos. Chem. Phys., 21, 1737–1757, https://doi.org/10.5194/acp-21-1737-2021, https://doi.org/10.5194/acp-21-1737-2021, 2021
Short summary
Short summary
Arctic clouds play a role in modulating sea ice extent. Importantly, aerosols facilitate cloud formation, and thus it is crucial to understand the interactions between aerosols and clouds. Vertical measurements of aerosols and clouds are needed to tackle this issue. We present results from balloon-borne measurements of aerosols and clouds over the course of 2 years in northern Alaska. These data shed light onto the vertical distributions of aerosols relative to clouds spanning multiple seasons.
Jens Redemann, Robert Wood, Paquita Zuidema, Sarah J. Doherty, Bernadette Luna, Samuel E. LeBlanc, Michael S. Diamond, Yohei Shinozuka, Ian Y. Chang, Rei Ueyama, Leonhard Pfister, Ju-Mee Ryoo, Amie N. Dobracki, Arlindo M. da Silva, Karla M. Longo, Meloë S. Kacenelenbogen, Connor J. Flynn, Kristina Pistone, Nichola M. Knox, Stuart J. Piketh, James M. Haywood, Paola Formenti, Marc Mallet, Philip Stier, Andrew S. Ackerman, Susanne E. Bauer, Ann M. Fridlind, Gregory R. Carmichael, Pablo E. Saide, Gonzalo A. Ferrada, Steven G. Howell, Steffen Freitag, Brian Cairns, Brent N. Holben, Kirk D. Knobelspiesse, Simone Tanelli, Tristan S. L'Ecuyer, Andrew M. Dzambo, Ousmane O. Sy, Greg M. McFarquhar, Michael R. Poellot, Siddhant Gupta, Joseph R. O'Brien, Athanasios Nenes, Mary Kacarab, Jenny P. S. Wong, Jennifer D. Small-Griswold, Kenneth L. Thornhill, David Noone, James R. Podolske, K. Sebastian Schmidt, Peter Pilewskie, Hong Chen, Sabrina P. Cochrane, Arthur J. Sedlacek, Timothy J. Lang, Eric Stith, Michal Segal-Rozenhaimer, Richard A. Ferrare, Sharon P. Burton, Chris A. Hostetler, David J. Diner, Felix C. Seidel, Steven E. Platnick, Jeffrey S. Myers, Kerry G. Meyer, Douglas A. Spangenberg, Hal Maring, and Lan Gao
Atmos. Chem. Phys., 21, 1507–1563, https://doi.org/10.5194/acp-21-1507-2021, https://doi.org/10.5194/acp-21-1507-2021, 2021
Short summary
Short summary
Southern Africa produces significant biomass burning emissions whose impacts on regional and global climate are poorly understood. ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) is a 5-year NASA investigation designed to study the key processes that determine these climate impacts. The main purpose of this paper is to familiarize the broader scientific community with the ORACLES project, the dataset it produced, and the most important initial findings.
Chuanyang Shen, Gang Zhao, Weilun Zhao, Ping Tian, and Chunsheng Zhao
Atmos. Chem. Phys., 21, 1375–1388, https://doi.org/10.5194/acp-21-1375-2021, https://doi.org/10.5194/acp-21-1375-2021, 2021
Short summary
Short summary
Submicron particles larger than 300 nm dominate the aerosol light extinction and mass concentration in the urban environment. Aerosol hygroscopic properties extended to 600 nm were investigated at an urban site. Our results find that there exists a large fraction of a less hygroscopic group above 300 nm, and the hygroscopicity in this size range is enhanced significantly with the development of pollution levels. The hygroscopicity variation contributes greatly to the low visibility.
Krista Luoma, Jarkko V. Niemi, Minna Aurela, Pak Lun Fung, Aku Helin, Tareq Hussein, Leena Kangas, Anu Kousa, Topi Rönkkö, Hilkka Timonen, Aki Virkkula, and Tuukka Petäjä
Atmos. Chem. Phys., 21, 1173–1189, https://doi.org/10.5194/acp-21-1173-2021, https://doi.org/10.5194/acp-21-1173-2021, 2021
Short summary
Short summary
This study combined black carbon measurements from 15 Finnish sites that represented different environments (traffic, detached housing area, urban background, and regional background). The seasonal and diurnal variations in the black carbon concentration were associated with local emissions from traffic and residential wood burning. The study observed decreasing trends in the black carbon concentration and associated them with decreases in traffic emissions.
Nobuyuki Takegawa, Yoshiko Murashima, Akihiro Fushimi, Kentaro Misawa, Yuji Fujitani, Katsumi Saitoh, and Hiromu Sakurai
Atmos. Chem. Phys., 21, 1085–1104, https://doi.org/10.5194/acp-21-1085-2021, https://doi.org/10.5194/acp-21-1085-2021, 2021
Short summary
Short summary
The characterization of particle emissions from aircraft is important for the assessment of the aviation impacts on climate and human health. We conducted field observations of aerosols near a runway at Narita International Airport in February 2018. We investigated particle number emissions from in-use commercial aircraft under real-world operating conditions, and we found the significance of sub-10 nm size ranges in take-off plumes for both total and non-volatile particles.
Jim M. Haywood, Steven J. Abel, Paul A. Barrett, Nicolas Bellouin, Alan Blyth, Keith N. Bower, Melissa Brooks, Ken Carslaw, Haochi Che, Hugh Coe, Michael I. Cotterell, Ian Crawford, Zhiqiang Cui, Nicholas Davies, Beth Dingley, Paul Field, Paola Formenti, Hamish Gordon, Martin de Graaf, Ross Herbert, Ben Johnson, Anthony C. Jones, Justin M. Langridge, Florent Malavelle, Daniel G. Partridge, Fanny Peers, Jens Redemann, Philip Stier, Kate Szpek, Jonathan W. Taylor, Duncan Watson-Parris, Robert Wood, Huihui Wu, and Paquita Zuidema
Atmos. Chem. Phys., 21, 1049–1084, https://doi.org/10.5194/acp-21-1049-2021, https://doi.org/10.5194/acp-21-1049-2021, 2021
Short summary
Short summary
Every year, the seasonal cycle of biomass burning from agricultural practices in Africa creates a huge plume of smoke that travels many thousands of kilometres over the Atlantic Ocean. This study provides an overview of a measurement campaign called the cloud–aerosol–radiation interaction and forcing for year 2017 (CLARIFY-2017) and documents the rationale, deployment strategy, observations, and key results from the campaign which utilized the heavily equipped FAAM atmospheric research aircraft.
Huikun Liu, Qiyuan Wang, Li Xing, Yong Zhang, Ting Zhang, Weikang Ran, and Junji Cao
Atmos. Chem. Phys., 21, 973–987, https://doi.org/10.5194/acp-21-973-2021, https://doi.org/10.5194/acp-21-973-2021, 2021
Short summary
Short summary
We conducted black carbon (BC) source apportionment on the southeastern Tibetan Plateau (TP) by an improved aethalometer model with the site-dependent Ångström exponent and BC mass absorption cross section (MAC). The result shows that the biomass-burning BC on the TP is slightly higher than fossil fuel BC, mainly from cross-border transportation instead of the local region, and the BC radiative effect is lower than that in the southwestern Himalaya but higher than that on the northeastern TP.
Vasiliki Daskalopoulou, Sotirios A. Mallios, Zbigniew Ulanowski, George Hloupis, Anna Gialitaki, Ioanna Tsikoudi, Konstantinos Tassis, and Vassilis Amiridis
Atmos. Chem. Phys., 21, 927–949, https://doi.org/10.5194/acp-21-927-2021, https://doi.org/10.5194/acp-21-927-2021, 2021
Short summary
Short summary
This research highlights the detection of charged Saharan dust in Greece and provides indications of charge separation in the plumes through the first-ever co-located ground electric field measurements and sophisticated lidar observations. We provide a robust methodology for the extraction of a fair-weather proxy field used to assess the effect of lofted dust particles to the electric field and insert a realistic modelling aspect to the charge accumulation areas within electrically active dust.
Juha Sulo, Nina Sarnela, Jenni Kontkanen, Lauri Ahonen, Pauli Paasonen, Tiia Laurila, Tuija Jokinen, Juha Kangasluoma, Heikki Junninen, Mikko Sipilä, Tuukka Petäjä, Markku Kulmala, and Katrianne Lehtipalo
Atmos. Chem. Phys., 21, 695–715, https://doi.org/10.5194/acp-21-695-2021, https://doi.org/10.5194/acp-21-695-2021, 2021
Short summary
Short summary
In this study, we analyzed over 5 years of sub-3 nm particle concentrations and their precursor vapors, identifying atmoshperic vapors important to the formation of these particles in the boreal forest. We also observed seasonal differences in both particle and precursor vapor concentrations and the formation pathways of these particles. Our results confirm the importance of organic vapors in atmospheric aerosol formation and highlight key seasonal differences that require further study.
Jinfeng Yuan, Robin Lewis Modini, Marco Zanatta, Andreas B. Herber, Thomas Müller, Birgit Wehner, Laurent Poulain, Thomas Tuch, Urs Baltensperger, and Martin Gysel-Beer
Atmos. Chem. Phys., 21, 635–655, https://doi.org/10.5194/acp-21-635-2021, https://doi.org/10.5194/acp-21-635-2021, 2021
Short summary
Short summary
Black carbon (BC) aerosols contribute substantially to climate warming due to their unique light absorption capabilities. We performed field measurements at a central European background site in winter and found that variability in the absorption efficiency of BC particles is driven mainly by their internal mixing state. Our results suggest that, at this site, knowing the BC mixing state is sufficient to describe BC light absorption enhancements due to the lensing effect in good approximation.
Shuo Ding, Dantong Liu, Kang Hu, Delong Zhao, Ping Tian, Fei Wang, Ruijie Li, Yichen Chen, Hui He, Mengyu Huang, and Deping Ding
Atmos. Chem. Phys., 21, 681–694, https://doi.org/10.5194/acp-21-681-2021, https://doi.org/10.5194/acp-21-681-2021, 2021
Short summary
Short summary
In this study, we for the first time characterized the detailed black carbon (BC) microphysics at a mountain site located at the top of the planetary boundary layer (PBL) influenced by surface emission over the North China Plain. We investigated the optical and hygroscopic properties of BC at this level as influenced by microphysical properties. Such information will constrain the impacts of BC in influencing the PBL dynamics and low-level cloud formation over anthropogenically polluted regions.
David Brus, Jani Gustafsson, Ville Vakkari, Osku Kemppinen, Gijs de Boer, and Anne Hirsikko
Atmos. Chem. Phys., 21, 517–533, https://doi.org/10.5194/acp-21-517-2021, https://doi.org/10.5194/acp-21-517-2021, 2021
Short summary
Short summary
This paper summarizes Finnish Meteorological Institute and Kansas State University unmanned aerial vehicle measurements during the summer 2018 Lower Atmospheric Process Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (LAPSE-RATE) campaign in the San Luis Valley, providing an overview of the rotorcraft deployed, payloads, scientific goals and flight strategies and presenting observations of atmospheric thermodynamics and aerosol and gas parameters in the vertical column.
Jesús Yus-Díez, Marina Ealo, Marco Pandolfi, Noemí Perez, Gloria Titos, Griša Močnik, Xavier Querol, and Andrés Alastuey
Atmos. Chem. Phys., 21, 431–455, https://doi.org/10.5194/acp-21-431-2021, https://doi.org/10.5194/acp-21-431-2021, 2021
Short summary
Short summary
Here we describe the vertical profiles of extensive (scattering and absorption) and intensive (e.g. albedo and asymmetry parameter) aerosol optical properties from coupling ground-based measurements from two sites in north-eastern Spain and airborne measurements performed with an aircraft. We analyse different aerosol layers along the vertical profile for a regional pollution episode and a Saharan dust intrusion. The results show a change with height depending on the different measured layers.
Carolina Ramírez-Romero, Alejandro Jaramillo, María F. Córdoba, Graciela B. Raga, Javier Miranda, Harry Alvarez-Ospina, Daniel Rosas, Talib Amador, Jong Sung Kim, Jacqueline Yakobi-Hancock, Darrel Baumgardner, and Luis A. Ladino
Atmos. Chem. Phys., 21, 239–253, https://doi.org/10.5194/acp-21-239-2021, https://doi.org/10.5194/acp-21-239-2021, 2021
Short summary
Short summary
Field measurements were conducted to confirm the arrival of African dust on the Yucatàn Peninsula. Aerosol particles were monitored at ground level by different online and off-line sensors. Several particulate matter peaks were observed with a relative increase in their levels of up to 500 % with respect to background conditions. Based on the chemical composition, back trajectories, vertical profiles, reanalysis, and satellite images, it was found that the peaks are linked to African dust.
Rutambhara Joshi, Dantong Liu, Eiko Nemitz, Ben Langford, Neil Mullinger, Freya Squires, James Lee, Yunfei Wu, Xiaole Pan, Pingqing Fu, Simone Kotthaus, Sue Grimmond, Qiang Zhang, Ruili Wu, Oliver Wild, Michael Flynn, Hugh Coe, and James Allan
Atmos. Chem. Phys., 21, 147–162, https://doi.org/10.5194/acp-21-147-2021, https://doi.org/10.5194/acp-21-147-2021, 2021
Short summary
Short summary
Black carbon (BC) is a component of particulate matter which has significant effects on climate and human health. Sources of BC include biomass burning, transport, industry and domestic cooking and heating. In this study, we measured BC emissions in Beijing, finding a dominance of traffic emissions over all other sources. The quantitative method presented here has benefits for revising widely used emissions inventories and for understanding BC sources with impacts on air quality and climate.
Joseph Ko, Trevor Krasowsky, and George Ban-Weiss
Atmos. Chem. Phys., 20, 15635–15664, https://doi.org/10.5194/acp-20-15635-2020, https://doi.org/10.5194/acp-20-15635-2020, 2020
Short summary
Short summary
Black carbon (BC) is the second strongest climate forcing pollutant in the atmosphere, after carbon dioxide. Here, we seek to understand how BC microphysical properties vary with atmospheric contexts, as these properties can influence its radiative forcing. Consistent with previous studies, we found that biomass burning BC had thicker coatings and larger core diameters than fossil fuel BC. We also present evidence to show that atmospheric aging also increases BC coating thickness.
Imre Salma, Máté Vörösmarty, András Zénó Gyöngyösi, Wanda Thén, and Tamás Weidinger
Atmos. Chem. Phys., 20, 15725–15742, https://doi.org/10.5194/acp-20-15725-2020, https://doi.org/10.5194/acp-20-15725-2020, 2020
Short summary
Short summary
Motor vehicle road traffic in Budapest was reduced by approximately 50% of its ordinary level due to COVID-19. In parallel, concentrations of most criteria air pollutants declined by 30–60%. Change rates of NO and NO2 with relative change in traffic intensity were the largest, total particle number concentration showed considerable dependency, while particulate matter mass concentrations did not appear to be related to urban traffic. Concentrations of O3 showed an increasing tendency.
Mingfu Cai, Baoling Liang, Qibin Sun, Li Liu, Bin Yuan, Min Shao, Shan Huang, Yuwen Peng, Zelong Wang, Haobo Tan, Fei Li, Hanbin Xu, and Jun Zhao
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1203, https://doi.org/10.5194/acp-2020-1203, 2020
Revised manuscript accepted for ACP
Short summary
Short summary
This study investigated the contribution of new particle formation (NPF) events to the number concentration of cloud condensation nuclei (NCCN) and its controlling factors in the Pearl River Delta region. The results show that the surfactant effect can decrease the critical diameter and significantly increase the NCCN during the NPF event. In addition, the growth rate is founded to be the most important controlling factor that affects NCCN for growth of newly-formed particles to the CCN sizes.
Qiyuan Wang, Li Li, Jiamao Zhou, Jianhuai Ye, Wenting Dai, Huikun Liu, Yong Zhang, Renjian Zhang, Jie Tian, Yang Chen, Yunfei Wu, Weikang Ran, and Junji Cao
Atmos. Chem. Phys., 20, 15427–15442, https://doi.org/10.5194/acp-20-15427-2020, https://doi.org/10.5194/acp-20-15427-2020, 2020
Short summary
Short summary
Recently, China has promulgated a series of regulations to reduce air pollutants. The decreased black carbon (BC) and co-emitted pollutants could affect the interactions between BC and other aerosols, which in turn results in changes in BC. Herein, we re-assessed the characteristics of BC of a representative pollution site in northern China in the final year of the Chinese
Action Plan for the Prevention and Control of Air Pollution.
Agnieszka Kupc, Christina J. Williamson, Anna L. Hodshire, Jan Kazil, Eric Ray, T. Paul Bui, Maximilian Dollner, Karl D. Froyd, Kathryn McKain, Andrew Rollins, Gregory P. Schill, Alexander Thames, Bernadett B. Weinzierl, Jeffrey R. Pierce, and Charles A. Brock
Atmos. Chem. Phys., 20, 15037–15060, https://doi.org/10.5194/acp-20-15037-2020, https://doi.org/10.5194/acp-20-15037-2020, 2020
Short summary
Short summary
Tropical upper troposphere over the Atlantic and Pacific oceans is a major source region of new particles. These particles are associated with the outflow from deep convection. We investigate the processes that govern the formation of these particles and their initial growth and show that none of the formation schemes commonly used in global models are consistent with observations. Using newer schemes indicates that organic compounds are likely important as nucleating and initial growth agents.
Yuan Wang, Xiaojian Zheng, Xiquan Dong, Baike Xi, Peng Wu, Timothy Logan, and Yuk L. Yung
Atmos. Chem. Phys., 20, 14741–14755, https://doi.org/10.5194/acp-20-14741-2020, https://doi.org/10.5194/acp-20-14741-2020, 2020
Short summary
Short summary
A recent aircraft field campaign near the Azores in the summer of 2017 provides ample observations of aerosols and clouds with detailed vertical information. This study utilizes those observational data in combination with the aerosol-aware large-eddy simulations and aerosol reanalysis data to examine the significance of the long-range-transported aerosol effect on marine-boundary-layer clouds. It is the first time that the ACE-ENA aircraft campaign data are used for this topic.
Douglas Morrison, Ian Crawford, Nicholas Marsden, Michael Flynn, Katie Read, Luis Neves, Virginia Foot, Paul Kaye, Warren Stanley, Hugh Coe, David Topping, and Martin Gallagher
Atmos. Chem. Phys., 20, 14473–14490, https://doi.org/10.5194/acp-20-14473-2020, https://doi.org/10.5194/acp-20-14473-2020, 2020
Short summary
Short summary
We provide conservative estimates of the concentrations of bacteria within transatlantic dust clouds, originating from the African continent. We observe significant seasonal differences in the overall concentrations of particles but no seasonal variation in the ratio between bacteria and dust. With bacteria contributing to ice formation at warmer temperatures than dust, our observations should improve the accuracy of climate models.
Juan Andrés Casquero-Vera, Hassan Lyamani, Lubna Dada, Simo Hakala, Pauli Paasonen, Roberto Román, Roberto Fraile, Tuukka Petäjä, Francisco José Olmo-Reyes, and Lucas Alados-Arboledas
Atmos. Chem. Phys., 20, 14253–14271, https://doi.org/10.5194/acp-20-14253-2020, https://doi.org/10.5194/acp-20-14253-2020, 2020
Short summary
Short summary
New particle formation was investigated at two stations located close to each other but at different altitudes: urban and high-altitude sites. Results show that sulfuric acid is able to explain a minimal fraction contribution to the observed growth rates and point to the availability of volatile organic compounds as the main factor controlling NPF events at both sites. A closer analysis of the NPF events that were observed at high-altitude sites during a Saharan dust episode was carried out.
Caroline C. Womack, Katherine M. Manfred, Nicholas L. Wagner, Gabriela Adler, Alessandro Franchin, Kara D. Lamb, Ann M. Middlebrook, Joshua P. Schwarz, Charles A. Brock, Steven S. Brown, and Rebecca A. Washenfelder
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1200, https://doi.org/10.5194/acp-2020-1200, 2020
Preprint under review for ACP
Short summary
Short summary
Microscopic particles interact with sunlight and affect the earth's climate in ways that are not fully understood. Aerosols from wildfire smoke present particular challenges due to their complexity in shape and composition. We demonstrate that we can experimentally measure aerosol optical properties for many types of smoke particles, using measurements of smoke from controlled burns, but that the method does not work well for smoke with high soot content.
Junfeng Wang, Jianhuai Ye, Dantong Liu, Yangzhou Wu, Jian Zhao, Weiqi Xu, Conghui Xie, Fuzhen Shen, Jie Zhang, Paul E. Ohno, Yiming Qin, Xiuyong Zhao, Scot T. Martin, Alex K. Y. Lee, Pingqing Fu, Daniel J. Jacob, Qi Zhang, Yele Sun, Mindong Chen, and Xinlei Ge
Atmos. Chem. Phys., 20, 14091–14102, https://doi.org/10.5194/acp-20-14091-2020, https://doi.org/10.5194/acp-20-14091-2020, 2020
Short summary
Short summary
We compared the organics in total submicron matter and those coated on BC cores during summertime in Beijing and found large differences between them. Traffic-related OA was associated significantly with BC, while cooking-related OA did not coat BC. In addition, a factor likely originated from primary biomass burning OA was only identified in BC-containing particles. Such a unique BBOA requires further field and laboratory studies to verify its presence and elucidate its properties and impacts.
Qiaoyun Hu, Haofei Wang, Philippe Goloub, Zhengqiang Li, Igor Veselovskii, Thierry Podvin, Kaitao Li, and Mikhail Korenskiy
Atmos. Chem. Phys., 20, 13817–13834, https://doi.org/10.5194/acp-20-13817-2020, https://doi.org/10.5194/acp-20-13817-2020, 2020
Short summary
Short summary
This study presents the characteristics of Taklamakan dust particles derived from lidar measurements collected in the dust aerosol observation field campaign. It provides comprehensive parameters for Taklamakan dust properties and vertical distributions of Taklamakan dust. This paper also points out the importance of polluted dust which was frequently observed in the field campaign. The results contribute to improving knowledge about dust and reducing uncertainties in the climatic model.
Dominic Heslin-Rees, Maria Burgos, Hans-Christen Hansson, Radovan Krejci, Johan Ström, Peter Tunved, and Paul Zieger
Atmos. Chem. Phys., 20, 13671–13686, https://doi.org/10.5194/acp-20-13671-2020, https://doi.org/10.5194/acp-20-13671-2020, 2020
Short summary
Short summary
Aerosol particles are one important key player in the Arctic climate. Using long-term measurements of particle light scattering from an observatory on Svalbard, this study investigates the reasons behind an observed shift towards larger particles seen in the last 2 decades. We find that increases in sea spray are the most likely cause. Air masses from the south-west have increased significantly, suggestive of a potential mechanism, whilst the retreat in sea ice has a marginal influence.
Haebum Lee, Kwangyul Lee, Chris Rene Lunder, Radovan Krejci, Wenche Aas, Jiyeon Park, Ki-Tae Park, Bang Yong Lee, Young Jun Yoon, and Kihong Park
Atmos. Chem. Phys., 20, 13425–13441, https://doi.org/10.5194/acp-20-13425-2020, https://doi.org/10.5194/acp-20-13425-2020, 2020
Short summary
Short summary
New particle formation (NPF) contributes to enhance the number of particles in the ambient atmosphere, affecting local air quality and cloud condensation nuclei (CCN) concentration. This study investigated NPF characteristics in the Arctic and showed that although formation and growth rates of nanoparticles were much lower than those in continental areas, NPF occurrence frequency was comparable and marine biogenic sources played important roles in production of condensing vapors for NPF.
Lawrence I. Kleinman, Arthur J. Sedlacek III, Kouji Adachi, Peter R. Buseck, Sonya Collier, Manvendra K. Dubey, Anna L. Hodshire, Ernie Lewis, Timothy B. Onasch, Jeffery R. Pierce, John Shilling, Stephen R. Springston, Jian Wang, Qi Zhang, Shan Zhou, and Robert J. Yokelson
Atmos. Chem. Phys., 20, 13319–13341, https://doi.org/10.5194/acp-20-13319-2020, https://doi.org/10.5194/acp-20-13319-2020, 2020
Short summary
Short summary
Aerosols from wildfires affect the Earth's temperature by absorbing light or reflecting it back into space. This study investigates time-dependent chemical, microphysical, and optical properties of aerosols generated by wildfires in the Pacific Northwest, USA. Wildfire smoke plumes were traversed by an instrumented aircraft at locations near the fire and up to 3.5 h travel time downwind. Although there was no net aerosol production, aerosol particles grew and became more efficient scatters.
Pengguo Zhao, Zhanqing Li, Hui Xiao, Fang Wu, Youtong Zheng, Maureen C. Cribb, Xiaoai Jin, and Yunjun Zhou
Atmos. Chem. Phys., 20, 13379–13397, https://doi.org/10.5194/acp-20-13379-2020, https://doi.org/10.5194/acp-20-13379-2020, 2020
Short summary
Short summary
We discussed the different aerosol effects on lightning in plateau and basin regions of Sichuan, southwestern China. In the plateau area, the aerosol concentration is low, and aerosols (via microphysical effects) inhibit the process of warm rain and stimulate convection and lightning activity. In the basin region, however, aerosols tend to show a significant radiative effect (reducing the solar radiation reaching the surface by absorbing and scattering) and inhibit the lightning.
Ying Zhu, Jia Chen, Xiao Bi, Gerrit Kuhlmann, Ka Lok Chan, Florian Dietrich, Dominik Brunner, Sheng Ye, and Mark Wenig
Atmos. Chem. Phys., 20, 13241–13251, https://doi.org/10.5194/acp-20-13241-2020, https://doi.org/10.5194/acp-20-13241-2020, 2020
Short summary
Short summary
Average NO2 concentration of on-street mobile measurements (MMs) near the monitoring stations (MSs) was found to be considerably higher than the MSs data. The common measurement height (H) and distance (D) of the MSs result in 27 % lower average concentrations in total than the concentration of our MMs. Another 21 % difference remained after correcting the influence of the measuring H and D. This result makes our city-wide measurements for capturing the full range of concentrations necessary.
Maria Kezoudi, Matthias Tesche, Helen Smith, Alexandra Tsekeri, Holger Baars, Maximilian Dollner, Víctor Estellés, Bernadett Weinzierl, Zbigniew Ulanowski, Detlef Müller, and Vassilis Amiridis
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-977, https://doi.org/10.5194/acp-2020-977, 2020
Revised manuscript accepted for ACP
Huihui Wu, Jonathan W. Taylor, Kate Szpek, Justin M. Langridge, Paul I. Williams, Michael Flynn, James D. Allan, Steven J. Abel, Joseph Pitt, Michael I. Cotterell, Cathryn Fox, Nicholas W. Davies, Jim Haywood, and Hugh Coe
Atmos. Chem. Phys., 20, 12697–12719, https://doi.org/10.5194/acp-20-12697-2020, https://doi.org/10.5194/acp-20-12697-2020, 2020
Short summary
Short summary
Airborne measurements of highly aged biomass burning aerosols (BBAs) over the remote southeast Atlantic provide unique aerosol parameters for climate models. Our observations demonstrate the persistence of strongly absorbing BBAs across wide regions of the South Atlantic. We also found significant vertical variation in the single-scattering albedo of these BBAs, as a function of relative chemical composition and size. Aerosol properties in the marine BL are suggested to be separated from the FT.
Guangjie Zheng, Chongai Kuang, Janek Uin, Thomas Watson, and Jian Wang
Atmos. Chem. Phys., 20, 12515–12525, https://doi.org/10.5194/acp-20-12515-2020, https://doi.org/10.5194/acp-20-12515-2020, 2020
Short summary
Short summary
Condensational growth of Aitken-mode particles is a major source of cloud condensation nuclei in the remote marine boundary layer. It has been long thought that over remote oceans, condensation growth is dominated by sulfate that derives from ocean-emitted dimethyl sulfide. In this study, we present the first long-term observational evidence that, contrary to conventional thinking, organics play an even more important role than sulfate in particle growth over remote oceans throughout the year.
Anbao Zhu, Haiming Xu, Jiechun Deng, Jing Ma, and Shuhui Li
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-859, https://doi.org/10.5194/acp-2020-859, 2020
Revised manuscript accepted for ACP
Santtu Mikkonen, Zoltán Németh, Veronika Varga, Tamás Weidinger, Ville Leinonen, Taina Yli-Juuti, and Imre Salma
Atmos. Chem. Phys., 20, 12247–12263, https://doi.org/10.5194/acp-20-12247-2020, https://doi.org/10.5194/acp-20-12247-2020, 2020
Short summary
Short summary
We determined decennial statistical time trends and diurnal statistical patterns of atmospheric particle number concentrations in various relevant size fractions in the city centre of Budapest in an interval of 2008–2018. The mean overall decrease rate of particles in different size fractions was approximately −5 % scaled for the 10-year measurement interval. The decline can be interpreted as a consequence of the decreased anthropogenic emissions in the city.
Yijia Zhang, Zhicong Yin, and Huijun Wang
Atmos. Chem. Phys., 20, 12211–12221, https://doi.org/10.5194/acp-20-12211-2020, https://doi.org/10.5194/acp-20-12211-2020, 2020
Short summary
Short summary
Haze events in early winter in North China exhibited rapid growth after 2010, which was completely different from the slow decline observed before 2010. However, global warming and anthropogenic emissions could not explain this trend reversal well, which was puzzling. Our study found that four climate factors, exhibiting completely opposite trends before and after 2010, effectively drove the trend reversal of the haze pollution in North China.
Cited articles
4STAR Team: LeBlanc, S., Flynn, C. J., Shinozuka, Y.,
Segal-Rozenhaimer, M., Pistone, K., Kacenelenbogen, M.,
Redemann, J., Schmid, B., Russell, P., Livingston, J., and Zhang, Q.:
4STAR_codes: 4STAR processing codes,
https://doi.org/10.5281/zenodo.1492912, 2018.
Adebiyi, A. A., Zuidema, P., and Abel, S. J.: The convolution of dynamics and
moisture with the presence of shortwave absorbing aerosols over the
southeast Atlantic, J. Climate, 28, 1997–2024,
https://doi.org/10.1175/JCLI-D-14-00352.1, 2015.
Ångström, A.: On the Atmospheric Transmission of Sun Radiation and
on Dust in the Air, Geogr. Ann., 11, 156–166,
https://doi.org/10.1080/20014422.1929.11880498, 1929.
Bergstrom, R., Pilewskie, P., Schmid, B., and Russell, P. B.: Estimates of
the spectral aerosol single scattering albedo and aerosol radiative effects
during SAFARI 2000, J. Geophys. Res., 108, 1–11,
https://doi.org/10.1029/2002JD002435, 2003.
Bond, T. C., Doherty, S. J., Fahey, D. W., Forster, P. M., Berntsen, T.,
Deangelo, B. J., Flanner, M. G., Ghan, S., Kärcher, B., Koch, D., Kinne,
S., Kondo, Y., Quinn, P. K., Sarofim, M. C., Schultz, M. G., Schulz, M.,
Venkataraman, C., Zhang, H., Zhang, S., Bellouin, N., Guttikunda, S. K.,
Hopke, P. K., Jacobson, M. Z., Kaiser, J. W., Klimont, Z., Lohmann, U.,
Schwarz, J. P., Shindell, D., Storelvmo, T., Warren, S. G., and Zender, C.
S.: Bounding the role of black carbon in the climate system: A scientific
assessment, J. Geophys. Res.-Atmos., 118, 5380–5552,
https://doi.org/10.1002/jgrd.50171, 2013.
Chang, I. and Christopher, S. A.: Identifying Absorbing Aerosols above Clouds from the Spinning Enhanced Visible and Infrared Imager Coupled with NASA A-Train Multiple Sensors, IEEE T. Geosci. Remote, 54, 3163–3173, https://doi.org/10.1109/TGRS.2015.2513015, 2016.
Chang, I. and Christopher, S. A.: The impact of seasonalities on direct radiative
effects and radiative heating rates of absorbing aerosols above clouds, Q.
J. Roy. Meteor. Soc., 143, 1395–1405, https://doi.org/10.1002/qj.3012, 2017.
Chuang, P. Y., Saw, E. W., Small, J. D., Shaw, R. A., Sipperley, C. M.,
Payne, G. A., and Bachalo, W. D.: Airborne Phase Doppler Interferometry for Cloud
Microphysical Measurements, Aerosol Sci. Tech., 42, 685–703,
https://doi.org/10.1080/02786820802232956, 2008.
Cornet, C., C.-Labonnote, L., Waquet, F., Szczap, F., Deaconu, L., Parol, F., Vanbauce, C., Thieuleux, F., and Riédi, J.: Cloud heterogeneity on cloud and aerosol above cloud properties retrieved from simulated total and polarized reflectances, Atmos. Meas. Tech., 11, 3627–3643, https://doi.org/10.5194/amt-11-3627-2018, 2018.
Deaconu, L. T., Waquet, F., Josset, D., Ferlay, N., Peers, F., Thieuleux, F., Ducos, F., Pascal, N., Tanré, D., Pelon, J., and Goloub, P.: Consistency of aerosols above clouds characterization from A-Train active and passive measurements, Atmos. Meas. Tech., 10, 3499–3523, https://doi.org/10.5194/amt-10-3499-2017, 2017.
Deaconu, L. T., Ferlay, N., Waquet, F., Peers, F., Thieuleux, F., and Goloub, P.: Satellite inference of water vapour and above-cloud aerosol combined effect on radiative budget and cloud-top processes in the southeastern Atlantic Ocean, Atmos. Chem. Phys., 19, 11613–11634, https://doi.org/10.5194/acp-19-11613-2019, 2019.
De Graaf, M., Tilstra, L. G., Wang, P., and Stammes, P.: Retrieval of the
aerosol direct radiative effect over clouds from spaceborne spectrometry, J.
Geophys. Res., 117, D07207, https://doi.org/10.1029/2011JD017160, 2012.
Devasthale, A. and Thomas, M. A.: A global survey of aerosol-liquid water cloud overlap based on four years of CALIPSO-CALIOP data, Atmos. Chem. Phys., 11, 1143–1154, https://doi.org/10.5194/acp-11-1143-2011, 2011.
Diamond, M. S., Dobracki, A., Freitag, S., Small Griswold, J. D., Heikkila, A., Howell, S. G., Kacarab, M. E., Podolske, J. R., Saide, P. E., and Wood, R.: Time-dependent entrainment of smoke presents an observational challenge for assessing aerosol–cloud interactions over the southeast Atlantic Ocean, Atmos. Chem. Phys., 18, 14623–14636, https://doi.org/10.5194/acp-18-14623-2018, 2018.
Dubovik, O., Holben, B., Eck, T. F., Smirnov, A., Kaufman, Y. J., King, M.
D., Tanré, D., and Slutsker, I.: Variability of Absorption and Optical
Properties of Key Aerosol Types Observed in Worldwide Locations, J. Atmos.
Sci., 59, 590–608, https://doi.org/10.1175/1520-0469(2002)059<0590:VOAAOP>2.0.CO;2, 2002.
Dunagan, S. E., Johnson, R., Zavaleta, J., Russell, P. B., Schmid, B.,
Flynn, C., Redemann, J., Shinozuka, Y., Livingston, J., and
Segal-Rosenhaimer, M.: Spectrometer for Sky-Scanning Sun-Tracking
Atmospheric Research (4STAR): Instrument technology, Remote Sens., 5,
3872–3895, https://doi.org/10.3390/rs5083872, 2013.
Eck, T., Holben, B., and Reid, J.: Wavelength dependence of the optical depth
of biomass burning, urban, and desert dust aerosols, J. Geophys. Res.-Atmos.,
104, 31333–31349, https://doi.org/10.1029/1999JD900923, 1999.
Eck, T. F., Holben, B. N., Ward, D. E., Mukelabai, M. M., Dubovik, O.,
Smirnov, A., Schafer, J. S., Hsu, N. C., Piketh, S. J., Queface, A., Roux,
J. Le, Swap, R. J., and Slutsker, I.: Variability of biomass burning aerosol
optical characteristics in southern Africa during the SAFARI 2000 dry season
campaign and a comparison of single scattering albedo estimates from
radiometric measurements, J. Geophys. Res.-Atmos., 108, 8477,
https://doi.org/10.1029/2002JD002321, 2003.
Feng, N. and Christopher, S. A.: Measurement-based estimates of direct
radiative effects of absorbing aerosols above clouds, J. Geophys. Res.-Atmos., 120, 6908–6921, https://doi.org/10.1002/2015JD023252, 2015.
Formenti, P., D'Anna, B., Flamant, C., Mallet, M., Piketh, S. J.,
Schepanski, K., Waquet, F., Auriol, F., Brogniez, G., Burnet, F.,
Chaboureau, J.-P., Chauvigné, A., Chazette, P., Denjean, C., Desboeufs,
K., Doussin, J.-F., Elguindi, N., Feuerstein, S., Gaetani, M., Giorio, C.,
Klopper, D., Mallet, M. D., Nabat, P., Monod, A., Solmon, F., Namwoonde, A.,
Chikwililwa, C., Mushi, R., Welton, E. J., and Holben, B.: The Aerosols,
Radiation and Clouds in southern Africa (AEROCLO-sA) field campaign in
Namibia: overview, illustrative observations and way forward, B. Am.
Meteorol. Soc., 100, 1277–1298, https://doi.org/10.1175/BAMS-D-17-0278.1, 2019.
Graßl, H.: Possible changes of planetary albedo due to aerosol
particles, in: Man's Impact on Climate, edited by: Bach, W., Pankrath, J., and
Kellogg, W., Elsevier, New York, 1979.
Haywood, J. M., Osborne, S. R., Francis, P. N., Keil, A., Formenti, P.,
Andreae, M. O., and Kaye, P. H.: The mean physical and optical properties of
regional haze dominated by biomass burning aerosol measured from the C-130
aircraft during SAFARI 2000, J. Geophys. Res., 108, 8473,
https://doi.org/10.1029/2002JD002226, 2003.
Hobbs, P. V.: Clean air slots amid dense atmospheric pollution in southern
Africa, J. Geophys. Res.-Atmos., 108, 8490, https://doi.org/10.1029/2002JD002156,
2003.
Holben, B. N., Eck, T. F., Slutsker, I., Tanre, D., Vermote, E., Reagan, J.
A., Kaufman, Y. J., Nakajima, T., Lavenu, F., Jankowiak, I., and Smirnov, A.:
AERONET – A Federated Instrument Network and Data Archive for Aerosol
Characterization, Remote Sens. Environ., 66, 1–16, https://doi.org/10.1016/S0034-4257(98)00031-5, 1998.
Holben, B. N., Kim, J., Sano, I., Mukai, S., Eck, T. F., Giles, D. M., Schafer, J. S., Sinyuk, A., Slutsker, I., Smirnov, A., Sorokin, M., Anderson, B. E., Che, H., Choi, M., Crawford, J. H., Ferrare, R. A., Garay, M. J., Jeong, U., Kim, M., Kim, W., Knox, N., Li, Z., Lim, H. S., Liu, Y., Maring, H., Nakata, M., Pickering, K. E., Piketh, S., Redemann, J., Reid, J. S., Salinas, S., Seo, S., Tan, F., Tripathi, S. N., Toon, O. B., and Xiao, Q.: An overview of mesoscale aerosol processes, comparisons, and validation studies from DRAGON networks, Atmos. Chem. Phys., 18, 655–671, https://doi.org/10.5194/acp-18-655-2018, 2018.
Howell, S. G., Clarke, A. D., Shinozuka, Y., Kapustin, V., McNaughton, C.
S., Huebert, B. J., Doherty, S. J., and Anderson, T. L.: Influence of
relative humidity upon pollution and dust during ACE-Asia: Size
distributions and implications for optical properties, J. Geophys. Res.-Atmos., 111, 1–11, https://doi.org/10.1029/2004JD005759, 2006.
Hu, Y., Vaughan, M., Liu, Z., Powell, K., and Rodier, S.: Retrieving Optical
Depths and Lidar Ratios for Transparent Layers Above Opaque Water Clouds
From CALIPSO Lidar Measurements, IEEE Geosci. Remote, 4, 523–526, 2007.
Jethva, H., Torres, O., Remer, L. A., and Bhartia, P. K.: A color ratio method
for simultaneous retrieval of aerosol and cloud optical thickness of
above-cloud absorbing aerosols from passive sensors: Application to MODIS
measurements, IEEE T. Geosci. Remote, 51, 3862–3870,
https://doi.org/10.1109/TGRS.2012.2230008, 2013.
Jethva, H., Torres, O., Waquet, F., Chand, D., and Hu, Y.: How do A-train
sensors intercompare in the retrieval of above cloud aerosol optical depth?
A case study-based assessment, Geophys. Res. Lett., 41, 1–7,
https://doi.org/10.1002/2013GL058405, 2014.
Kacenelenbogen, M. S., Vaughan, M. A., Redemann, J., Young, S. A., Liu, Z., Hu, Y., Omar, A. H., LeBlanc, S., Shinozuka, Y., Livingston, J., Zhang, Q., and Powell, K. A.: Estimations of global shortwave direct aerosol radiative effects above opaque water clouds using a combination of A-Train satellite sensors, Atmos. Chem. Phys., 19, 4933–4962, https://doi.org/10.5194/acp-19-4933-2019, 2019.
Kaskaoutis, D. G. and Kambezidis, H. D.: Comparison of the Ångström
parameters retrieval in different spectral ranges with the use of different
techniques, Meteorol. Atmos. Phys., 99, 233–246, https://doi.org/10.1007/s00703-007-0279-y, 2008.
Keil, A. and Haywood, J. M.: Solar radiative forcing by biomass burning
aerosol particles during SAFARI 2000: A case study based on measured aerosol
and cloud properties, J. Geophys. Res.-Atmos., 108, 8467,
https://doi.org/10.1029/2002JD002315, 2003.
LeBlanc, S. E.: samuelleblanc/fp: Moving Lines: NASA airborne research
flight planning tool release, https://doi.org/10.5281/zenodo.1478126, 2018.
LeBlanc, S. E., Schmidt, K. S., Pilewskie, P., Redemann, J., Hostetler, C.,
Ferrare, R., Hair, J., Langridge, J. M., and Lack, D. A.: Spectral aerosol
direct radiative forcing from airborne radiative measurements during CalNex
and ARCTAS, J. Geophys. Res., 117, D00V20, https://doi.org/10.1029/2012JD018106, 2012.
Levy, R. C., Remer, L. A., and Dubovik, O.: Global aerosol optical properties
and application to Moderate Resolution Imaging Spectroradiometer aerosol
retrieval over land, J. Geophys. Res., 112, 1–15,
https://doi.org/10.1029/2006JD007815, 2007.
Levy, R. C., Remer, L. A., Tanre, D., Mattoo, S., and Kaufman, Y. J.: Algorithm
for remote sensing of tropospheric aerosol over dark targets from MODIS,
ATBD Reference Number: ATBD-MOD-04, 2009.
Levy, R. C., Mattoo, S., Munchak, L. A., Remer, L. A., Sayer, A. M., Patadia, F., and Hsu, N. C.: The Collection 6 MODIS aerosol products over land and ocean, Atmos. Meas. Tech., 6, 2989–3034, https://doi.org/10.5194/amt-6-2989-2013, 2013.
Liu, X., Huey, G., Yokelson, R. J., Selimovic, V., Simpson, I., Müller,
M., Jimenez, J., Campuzano-Jost, P., Beyersdorf, A., Blake, D., Butterfield,
Z., Choi, Y., Crounse, J., Day, D., Diskin, G., Dubey, M., Fortner, E.,
Hanisco, T., Weiwei, H., King, L., Kleinman, L., Meinardi, S., Mikoviny, T.,
Onasch, T., Palm, B., Peischl, J., Pollack, I., Ryerson, T., Sachse, G.,
Sedlacek, A., Shilling, J., Springston, S., St. Clair, J., Tanner, D., Teng,
A., Wennberg, P., Wisthaler, A., and Wolfe, G.: Airborne measurements of
western U.S. wildfire emissions: Comparison with prescribed burning and air
quality implications, J. Geophys. Res.-Atmos., 122, 6108–6129,
https://doi.org/10.1002/2016JD026315, 2017.
Lohmann, U. and Feichter, J.: Global indirect aerosol effects: a review, Atmos. Chem. Phys., 5, 715–737, https://doi.org/10.5194/acp-5-715-2005, 2005.
Matus, A. V., L'Ecuyer, T. S., Kay, J. E., Hannay, C., and Lamarque, J.-F.: The role of clouds in modulating global aerosol
direct radiative effects in spaceborne active observations and the Community
Earth System Model, J. Climate, 28, 2986–3003, 2015.
McGill, M. J., Yorks, J. E., Scott, V. S., Kupchock, A. W., and Selmer, P. A.:
The Cloud-Aerosol Transport System (CATS): a technology demonstration on the
International Space Station, Proc. SPIE, 9612, 34–39,
https://doi.org/10.1117/12.2190841, 2015.
McNaughton, C. S., Clarke, A. D., Howell, S. G., Anderson, B., Thornhill,
L., Hudgins, C., Dibb, J. E., Scheuer, E., Maring, H., Mcnaughton, C. S.,
Clarke, A. D., Howell, S. G., Anderson, B., Thornhill, L., Hudgins, C.,
Winstead, E., Dibb, J. E., Mcnaughton, C. S., Clarke, A. D., Howell, S. G.,
Pinkerton, M., Anderson, B., Thornhill, L., Hudgins, C., Winstead, E., Dibb,
J. E., Scheuer, E., and Maring, H.: Results from the DC-8 Inlet
Characterization Experiment (DICE): Airborne Versus Surface Sampling of
Mineral Dust and Sea Salt Aerosols Results from the DC-8 Inlet
Characterization Experiment (DICE): Airborne Versus Surface Sampling of
Mineral Dust and, Aerosol Sci. Tech., 6826, 136–159,
https://doi.org/10.1080/02786820601118406, 2007.
Meyer, K., Platnick, S., and Zhang, Z.: Simultaneously inferring above-cloud
absorbing aerosol optical thickness and underlying liquid phase cloud
optical and microphysical properties using MODIS, J. Geophys. Res.-Atmos.,
120, 5524–5547, https://doi.org/10.1002/2015JD023128, 2015.
ORACLES Science Team: Suite of Aerosol, Cloud, and Related Data Acquired
Aboard P3 During ORACLES 2016, Version 1, NASA Ames Earth Science Project
Office, https://doi.org/10.5067/Suborbital/ORACLES/P3/2016_V1, 2017.
Peers, F., Waquet, F., Cornet, C., Dubuisson, P., Ducos, F., Goloub, P., Szczap, F., Tanré, D., and Thieuleux, F.: Absorption of aerosols above clouds from POLDER/PARASOL measurements and estimation of their direct radiative effect, Atmos. Chem. Phys., 15, 4179–4196, https://doi.org/10.5194/acp-15-4179-2015, 2015.
Pistone, K., Redemann, J., Doherty, S., Zuidema, P., Burton, S., Cairns, B., Cochrane, S., Ferrare, R., Flynn, C., Freitag, S., Howell, S. G., Kacenelenbogen, M., LeBlanc, S., Liu, X., Schmidt, K. S., Sedlacek III, A. J., Segal-Rozenhaimer, M., Shinozuka, Y., Stamnes, S., van Diedenhoven, B., Van Harten, G., and Xu, F.: Intercomparison of biomass burning aerosol optical properties from in situ and remote-sensing instruments in ORACLES-2016, Atmos. Chem. Phys., 19, 9181–9208, https://doi.org/10.5194/acp-19-9181-2019, 2019.
Platnick, S., Meyer, K. G., King, M. D., Wind, G., Amarasinghe, N.,
Marchant, B., Arnold, G. T., Zhang, Z., Hubanks, P. A., Holz, R. E., Yang,
P., Ridgway, W. L., and Riedi, J.: The MODIS Cloud Optical and Microphysical
Products: Collection 6 Updates and Examples From Terra and Aqua, IEEE T.
Geosci. Remote, 55, 502–525, https://doi.org/10.1109/TGRS.2016.2610522, 2017.
Pósfai, M., Simonics, R., Li, J., Hobbs, P. V., and Buseck, P. R.:
Individual aerosol particles from biomass burning in southern Africa: 1.
Compositions and size distributions of carbonaceous particles, J. Geophys.
Res.-Atmos., 108, 8483, https://doi.org/10.1029/2002JD002291, 2003.
Provencal, R., Gupta, M., Owano, T. G., Baer, D. S., Ricci, K. N., O'Keefe,
A., and Podolske, J. R.: Cavity-enhanced quantum-cascade laser-based
instrument for carbon monoxide measurements, Appl. Optics, 44, 6712–6717,
https://doi.org/10.1364/AO.44.006712, 2005.
Quinn, P. K., Bates, T. S., Baynard, T., Clarke, A. D., Onasch, T. B., Wang,
W., Rood, M. J., Andrews, E., Allan, J., Carrico, C. M., Coffman, D., and
Worsnop, D.: Impact of particulate organic matter on the relative humidity
dependence of light scattering: A simplified parameterization, Geophys. Res.
Lett., 32, 3–6, https://doi.org/10.1029/2005GL024322, 2005.
Rajapakshe, C., Zhang, Z., Yorks, J. E., Yu, H., Tan, Q., Meyer, K.,
Platnick, S., and Winker, D. M.: Seasonally transported aerosol layers over
southeast Atlantic are closer to underlying clouds than previously reported,
Geophys. Res. Lett., 44, 5818–5825, https://doi.org/10.1002/2017GL073559, 2017.
Russell, P. B., Bergstrom, R. W., Shinozuka, Y., Clarke, A. D., DeCarlo, P. F., Jimenez, J. L., Livingston, J. M., Redemann, J., Dubovik, O., and Strawa, A.: Absorption Angstrom Exponent in AERONET and related data as an indicator of aerosol composition, Atmos. Chem. Phys., 10, 1155–1169, https://doi.org/10.5194/acp-10-1155-2010, 2010.
Russell, P. B., Kacenelenbogen, M., Livingston, J. M., Hasekamp, O. P.,
Redemann, J., Ramachandran, S., Holben, B., and Al, R. E. T.: A
multiparameter aerosol classification method and its application to
retrievals from spaceborne polarimetry, J. Geophys. Res.-Atmos., 119,
9838–9863, https://doi.org/10.1002/2013JD021411, 2014.
Sakaeda, N., Wood, R., and Rasch, P. J.: Direct and semidirect aerosol
effects of southern African biomass burning aerosol, J. Geophys. Res.-Atmos., 116, 1–19, https://doi.org/10.1029/2010JD015540, 2011.
Sayer, A. M., Smirnov, A., Hsu, N. C., and Holben, B. N.: A pure marine aerosol
model, for use in
remote sensing applications, J. Geophys. Res., 117, D05213,
https://doi.org/10.1029/2011JD016689,
2012.
Sayer, A. M., Hsu, N. C., Bettenhausen, C., Lee, J., Redemann, J., Schmid,
B., and Shinozuka, Y.: Extending “Deep Blue” aerosol retrieval coverage to
cases of absorbing aerosols above clouds: Sensitivity analysis and first
case studies, J. Geophys. Res.-Atmos., 121, 4830–4854,
https://doi.org/10.1002/2015JD024729, 2016.
Sayer, A. M., Hsu, N. C., Lee, J., Kim, W. V., Burton, S., Fenn, M. A., Ferrare, R. A., Kacenelenbogen, M., LeBlanc, S., Pistone, K., Redemann, J., Segal-Rozenhaimer, M., Shinozuka, Y., and Tsay, S.-C.: Two decades observing smoke above clouds in the south-eastern Atlantic Ocean: Deep Blue algorithm updates and validation with ORACLES field campaign data, Atmos. Meas. Tech., 12, 3595–3627, https://doi.org/10.5194/amt-12-3595-2019, 2019.
Schmid, B. and Wehrli, C.: Comparison of sun photometer calibration by
Langley technique and standard lamp, Appl. Optics, 34, 4500–4512, 1995.
Schulz, M., Textor, C., Kinne, S., Balkanski, Y., Bauer, S., Berntsen, T., Berglen, T., Boucher, O., Dentener, F., Guibert, S., Isaksen, I. S. A., Iversen, T., Koch, D., Kirkevåg, A., Liu, X., Montanaro, V., Myhre, G., Penner, J. E., Pitari, G., Reddy, S., Seland, Ø., Stier, P., and Takemura, T.: Radiative forcing by aerosols as derived from the AeroCom present-day and pre-industrial simulations, Atmos. Chem. Phys., 6, 5225–5246, https://doi.org/10.5194/acp-6-5225-2006, 2006.
Segal‐Rosenheimer, M., Russell, P. B., Schmid, B., Redemann, J., Livingston, J. M., Flynn, C. J., Johnson, R. R., Dunagan, S. E., Shinozuka, Y., Herman, J. R., Cede, A., Abuhassan, N., Comstock, J. M., Hubbe, J. M., Zelenyuk, A., and Wilson, J.: Tracking elevated pollution layers with a
newly developed hyperspectral Sun/Sky spectrometer (4STAR): Results from the
TCAP 2012 and 2013 campaigns, J. Geophys. Res.-Atmos., 119, 1–18,
https://doi.org/10.1002/2013JD020884, 2014.
Shinozuka, Y., Redemann, J., Livingston, J. M., Russell, P. B., Clarke, A. D., Howell, S. G., Freitag, S., O'Neill, N. T., Reid, E. A., Johnson, R., Ramachandran, S., McNaughton, C. S., Kapustin, V. N., Brekhovskikh, V., Holben, B. N., and McArthur, L. J. B.: Airborne observation of aerosol optical depth during ARCTAS: vertical profiles, inter-comparison and fine-mode fraction, Atmos. Chem. Phys., 11, 3673–3688, https://doi.org/10.5194/acp-11-3673-2011, 2011.
Shinozuka, Y., Saide, P. E., Ferrada, G. A., Burton, S. P., Ferrare, R., Doherty, S. J., Gordon, H., Longo, K., Mallet, M., Feng, Y., Wang, Q., Cheng, Y., Dobracki, A., Freitag, S., Howell, S. G., LeBlanc, S., Flynn, C., Segal-Rosenhaimer, M., Pistone, K., Podolske, J. R., Stith, E. J., Bennett, J. R., Carmichael, G. R., da Silva, A., Govindaraju, R., Leung, R., Zhang, Y., Pfister, L., Ryoo, J.-M., Redemann, J., Wood, R., and Zuidema, P.: Modeling the smoky troposphere of the southeast Atlantic: a comparison to ORACLES airborne observations from September of 2016, Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2019-678, in review, 2019.
Small, J. D., Chuang, P. Y., Feingold, G., and Jiang, H.: Can aerosol
decrease cloud lifetime?, Geophys. Res. Lett., 36, 1–5,
https://doi.org/10.1029/2009GL038888, 2009.
Stevens, B., Vali, G., Comstock, K., Wood, R., van Zanten, M. C., Austin, P. H.,
Bretherton, C. S., and Lenschow, D. H.: Pockets of open cells and drizzle in
marine stratocumulus, B. Am. Meteorol. Soc., 86, 51–58,
https://doi.org/10.1175/BAMS-86-1-51, 2005.
Torres, O., Hiren, J., and Bhartia, P. K.: Retrieval of aerosol optical depth
above clouds from OMI observations: Sensitivity analysis and case studies.
J. Atmos. Sci., 69, 1037–1053, 2012.
Twomey, S.: The influence of pollution on the shortwave albedo of clouds, J.
Atmos. Sci., 34, 1149–1152, 1977.
Twomey, S. A.: Pollution and the planetary albedo, Atmos. Environ., 8,
1251–1256, 1974.
Waquet, F., Riedi, J., Labonnote, L. C., Goloub, P., Cairns, B., Deuzé, J.-L.,
and Tanré, D.: Aerosol Remote Sensing over Clouds Using A-Train
Observations, J. Atmos. Sci., 66, 2468–2480, 2009.
Waquet, F., Peers, F., Ducos, F., Goloub, P., Platnick, S., Riedi, J.,
Tanré, D., and Thieuleux, F.: Global analysis of aerosol properties above
clouds, Geophys. Res. Lett., 40, 5809–5814, https://doi.org/10.1002/2013GL057482,
2013a.
Waquet, F., Cornet, C., Deuzé, J.-L., Dubovik, O., Ducos, F., Goloub, P., Herman, M., Lapyonok, T., Labonnote, L. C., Riedi, J., Tanré, D., Thieuleux, F., and Vanbauce, C.: Retrieval of aerosol microphysical and optical properties above liquid clouds from POLDER/PARASOL polarization measurements, Atmos. Meas. Tech., 6, 991–1016, https://doi.org/10.5194/amt-6-991-2013, 2013b.
Wen, G., Marshak, A., Cahalan, R. F., Remer, L. A., and Kleidman, R. G.: 3-D
aerosol-cloud radiative interaction observed in collocated MODIS and ASTER
images of cumulus cloud fields, J. Geophys. Res.-Atmos., 112, 1–14,
https://doi.org/10.1029/2006JD008267, 2007.
Wilcox, E. M.: Direct and semi-direct radiative forcing of smoke aerosols over clouds, Atmos. Chem. Phys., 12, 139–149, https://doi.org/10.5194/acp-12-139-2012, 2012.
Wood, R., Bretherton, C. S., Leon, D., Clarke, A. D., Zuidema, P., Allen, G., and Coe, H.: An aircraft case study of the spatial transition from closed to open mesoscale cellular convection over the Southeast Pacific, Atmos. Chem. Phys., 11, 2341–2370, https://doi.org/10.5194/acp-11-2341-2011, 2011.
Yoon, J., von Hoyningen-Huene, W., Kokhanovsky, A. A., Vountas, M., and Burrows, J. P.: Trend analysis of aerosol optical thickness and Ångström exponent derived from the global AERONET spectral observations, Atmos. Meas. Tech., 5, 1271–1299, https://doi.org/10.5194/amt-5-1271-2012, 2012.
Zarzycki, C. M. and Bond, T. C.: How much can the vertical distribution of
black carbon affect its global direct radiative forcing?, Geophys. Res.
Lett., 37, L20807, https://doi.org/10.1029/2010GL044555, 2010.
Zhang, Z., Meyer, K., Platnick, S., Oreopoulos, L., Lee, D., and Yu, H.: A novel method for estimating shortwave direct radiative effect of above-cloud aerosols using CALIOP and MODIS data, Atmos. Meas. Tech., 7, 1777–1789, https://doi.org/10.5194/amt-7-1777-2014, 2014.
Zhang, Z., Meyer, K., Yu, H., Platnick, S., Colarco, P., Liu, Z., and Oreopoulos, L.: Shortwave direct radiative effects of above-cloud aerosols over global oceans derived from 8 years of CALIOP and MODIS observations, Atmos. Chem. Phys., 16, 2877–2900, https://doi.org/10.5194/acp-16-2877-2016, 2016.
Zuidema, P., Redemann, J., Haywood, J., Wood, R., Piketh, S., Hipondoka, M.,
and Formenti, P.: Smoke and clouds above the southeast Atlantic: Upcoming
field campaigns probe absorbing aerosol's impact on climate, B. Am.
Meteorol. Soc., 97, 1131–1135, https://doi.org/10.1175/BAMS-D-15-00082.1, 2016.
Zuidema, P., Alvarado, M., Chiu, C., DeSzoeke, S., Fairall, C., Feingold,
G., Freedman, A., Ghan, S., Haywood, J., Kollias, P., Lewis, E., McFarquhar,
G., McComiskey, A., Mechem, D., Onasch, T., Redemann, J., Romps, D., Turner,
D., Wang, H., Wood, R., Yuter, S., and Zhu, P.: Layered Atlantic Smoke
Interactions with Clouds (LASIC) Field Campaign Report, DOE/ARM F. Campaign
Rep., 37, May 2018.
Short summary
The southeast Atlantic during August–October experiences layers of smoke from biomass burning over marine stratocumulus clouds. Here we present the light attenuation of the smoke and its dependence in the spatial, vertical, and spectral domain through direct measurements from an airborne platform during September 2016. From our observations of this climatically important smoke, we found an average aerosol optical depth of 0.32 at 500 nm, slightly lower than comparative satellite measurements.
The southeast Atlantic during August–October experiences layers of smoke from biomass burning...
Altmetrics
Final-revised paper
Preprint