Articles | Volume 18, issue 23
https://doi.org/10.5194/acp-18-16915-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-18-16915-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
29 Nov 2018
Research article |
| 29 Nov 2018
| 29 Nov 2018
Microphysical characteristics of frozen droplet aggregates from deep convective clouds
Junshik Um
CORRESPONDING AUTHOR
Department of Atmospheric Sciences, Pusan National
University, Busan, South Korea
Cooperative Institute for Mesoscale Meteorological Studies, University
of Oklahoma, Norman, Oklahoma, USA
Greg M. McFarquhar
Cooperative Institute for Mesoscale Meteorological Studies, University
of Oklahoma, Norman, Oklahoma, USA
School of Meteorology, University of Oklahoma, Norman, Oklahoma, USA
National Center for Atmospheric Research, Boulder, Colorado, USA
Jeffrey L. Stith
National Center for Atmospheric Research, Boulder, Colorado, USA
Chang Hoon Jung
Department of Health Management, Kyungin Women's University, Incheon,
South Korea
Seoung Soo Lee
Earth System Science Interdisciplinary Center, College Park, Maryland,
USA
Ji Yi Lee
Department of Environmental Science and Engineering, Ewha Womans
University, Seoul, South Korea
Younghwan Shin
Department of Agricultural and Biological Engineering, University of
Illinois, Urbana, Illinois, USA
Yun Gon Lee
Department of Atmospheric Sciences, Chungnam National University,
Daejeon, South Korea
Yiseok Isaac Yang
Department of Atmospheric Sciences, Yonsei University, Seoul, South
Korea
Seong Soo Yum
Department of Atmospheric Sciences, Yonsei University, Seoul, South
Korea
Byung-Gon Kim
Department of Atmospheric and Environmental Sciences, Gangneung-Wonju
National University, Gangneung, South Korea
Joo Wan Cha
Applied Meteorology Research Division, National Institute of
Meteorological Sciences, Jeju, South Korea
A-Reum Ko
Applied Meteorology Research Division, National Institute of
Meteorological Sciences, Jeju, South Korea
Related authors
Seoung Soo Lee, Chang Hoon Jung, Jinho Choi, Young Jun Yoon, Junshik Um, Youtong Zheng, Jianping Guo, Manguttathil G. Manoj, Sang-Keun Song, and Kyung-Ja Ha
Atmos. Chem. Phys., 25, 705–726, https://doi.org/10.5194/acp-25-705-2025, https://doi.org/10.5194/acp-25-705-2025, 2025
Short summary
Short summary
This study attempts to test a general factor that explains differences in the properties of different mixed-phase clouds using a modeling tool. Although this attempt is not to identify a factor that can perfectly explain and represent the properties of different mixed-phase clouds, we believe that this attempt acts as a valuable stepping stone towards a more complete, general way of using climate models to better predict climate change.
Jeonggyu Kim, Sungmin Park, Greg M. McFarquhar, Anthony J. Baran, Joo Wan Cha, Kyoungmi Lee, Seoung Soo Lee, Chang Hoon Jung, Kyo-Sun Sunny Lim, and Junshik Um
Atmos. Chem. Phys., 24, 12707–12726, https://doi.org/10.5194/acp-24-12707-2024, https://doi.org/10.5194/acp-24-12707-2024, 2024
Short summary
Short summary
We developed idealized models to represent the shapes of ice particles found in deep convective clouds and calculated their single-scattering properties. By comparing these results with in situ measurements, we discovered that a mixture of shape models matches in situ measurements more closely than single-form models or aggregate models. This finding has important implications for enhancing the simulation of single-scattering properties of ice crystals in deep convective clouds.
Seoung Soo Lee, Junshik Um, Won Jun Choi, Kyung-Ja Ha, Chang Hoon Jung, Jianping Guo, and Youtong Zheng
Atmos. Chem. Phys., 23, 273–286, https://doi.org/10.5194/acp-23-273-2023, https://doi.org/10.5194/acp-23-273-2023, 2023
Short summary
Short summary
This paper elaborates on process-level mechanisms regarding how the interception of radiation by aerosols interacts with the surface heat fluxes and atmospheric instability in warm cumulus clouds. This paper elucidates how these mechanisms vary with the location or altitude of an aerosol layer. This elucidation indicates that the location of aerosol layers should be taken into account for parameterizations of aerosol–cloud interactions.
Seoung Soo Lee, Jinho Choi, Goun Kim, Kyung-Ja Ha, Kyong-Hwan Seo, Chang Hoon Jung, Junshik Um, Youtong Zheng, Jianping Guo, Sang-Keun Song, Yun Gon Lee, and Nobuyuki Utsumi
Atmos. Chem. Phys., 22, 9059–9081, https://doi.org/10.5194/acp-22-9059-2022, https://doi.org/10.5194/acp-22-9059-2022, 2022
Short summary
Short summary
This study investigates how aerosols affect clouds and precipitation and how the aerosol effects vary with varying types of clouds that are characterized by cloud depth in two metropolitan areas in East Asia. As cloud depth increases, the enhancement of precipitation amount transitions to no changes in precipitation amount with increasing aerosol concentrations. This indicates that cloud depth needs to be considered for a comprehensive understanding of aerosol-cloud interactions.
Seoung Soo Lee, Kyung-Ja Ha, Manguttathil Gopalakrishnan Manoj, Mohammad Kamruzzaman, Hyungjun Kim, Nobuyuki Utsumi, Youtong Zheng, Byung-Gon Kim, Chang Hoon Jung, Junshik Um, Jianping Guo, Kyoung Ock Choi, and Go-Un Kim
Atmos. Chem. Phys., 21, 16843–16868, https://doi.org/10.5194/acp-21-16843-2021, https://doi.org/10.5194/acp-21-16843-2021, 2021
Short summary
Short summary
Using a modeling framework, a midlatitude stratocumulus cloud system is simulated. It is found that cloud mass in the system becomes very low due to interactions between ice and liquid particles compared to that in the absence of ice particles. It is also found that interactions between cloud mass and aerosols lead to a reduction in cloud mass in the system, and this is contrary to an aerosol-induced increase in cloud mass in the absence of ice particles.
Inyeob La, Wojciech W. Grabowski, Yongjoon Kim, Sanggyeom Kim, and Seong Soo Yum
Atmos. Chem. Phys., 26, 5213–5235, https://doi.org/10.5194/acp-26-5213-2026, https://doi.org/10.5194/acp-26-5213-2026, 2026
Short summary
Short summary
We ask how the amount of aerosol particles shapes cloud structure. Using computer simulations of a laboratory cloud chamber, we varied aerosol levels and tracked droplet growth. When aerosols are few, cloud water increases with height; when many, it becomes almost uniform because vapor is used up near the bottom. These findings clarify when upward motions matter and guide chamber design and better cloud treatment in weather and climate models.
Emily D. Lenhardt, Lan Gao, Siddhant Gupta, Greg M. McFarquhar, Feng Xu, Richard A. Ferrare, Chris A. Hostetler, and Jens Redemann
EGUsphere, https://doi.org/10.5194/egusphere-2026-853, https://doi.org/10.5194/egusphere-2026-853, 2026
Short summary
Short summary
Interactions between clouds and small particles in the atmosphere can cause changes to cloud properties such as how much of the sun's energy they reflect and whether precipitation is likely to occur. Here we use a new machine learning dataset to investigate these interactions using observations from the Southeast Atlantic. We find that smoke particles above cloud tops have a stronger impact on cloud properties than particles below clouds. This method can also be applied to satellite data.
Chanwoo Ahn, Andrew Loh, Najin Kim, Un Hyuk Yim, Joon Geon An, Kyung Hwan Kim, Donghwi Kim, Do-Hyeon Park, Seong Soo Yum, and Sun Choi
EGUsphere, https://doi.org/10.5194/egusphere-2026-842, https://doi.org/10.5194/egusphere-2026-842, 2026
Short summary
Short summary
Aerosols are tiny particles in the air, and some of them help form cloud droplets (called cloud condensation nuclei). Most ship measurements focus on only one ocean. To compare aerosols over several oceans, we measured them during a transit voyage of a research ship using the same method. The results show that properties of these particles cannot be represented by a single marine condition. Moreover, they changed widely, depending on where the air came from and the pathway it traveled.
Bu-Yo Kim, Miloslav Belorid, Joo Wan Cha, Youngmi Kim, and Seungbum Kim
Atmos. Meas. Tech., 18, 3781–3797, https://doi.org/10.5194/amt-18-3781-2025, https://doi.org/10.5194/amt-18-3781-2025, 2025
Short summary
Short summary
This study analyzed NaCl and CaCl2 powder-type hygroscopic materials for cloud seeding, using the Korea Cloud Physics Experimental Chamber (K-CPEC) in South Korea. The aerosol chamber enabled particle analysis in an extremely dry environment, while the cloud chamber, with precise pressure and temperature control, facilitated droplet growth through quasi-adiabatic expansion. Our study provides valuable insights for the development of new seeding materials and advanced cloud seeding experiments.
Kerry Meyer, Steven Platnick, G. Thomas Arnold, Nandana Amarasinghe, Daniel Miller, Jennifer Small-Griswold, Mikael Witte, Brian Cairns, Siddhant Gupta, Greg McFarquhar, and Joseph O'Brien
Atmos. Meas. Tech., 18, 981–1011, https://doi.org/10.5194/amt-18-981-2025, https://doi.org/10.5194/amt-18-981-2025, 2025
Short summary
Short summary
Satellite remote sensing retrievals of cloud droplet size are used to understand clouds and their interactions with aerosols and radiation but require many simplifying assumptions. Evaluation of these retrievals is typically done by comparing against direct measurements of droplets from airborne cloud probes. This paper details an evaluation of proxy airborne remote sensing droplet size retrievals against several cloud probes and explores the impact of key assumptions on retrieval agreement.
Seoung Soo Lee, Chang Hoon Jung, Jinho Choi, Young Jun Yoon, Junshik Um, Youtong Zheng, Jianping Guo, Manguttathil G. Manoj, Sang-Keun Song, and Kyung-Ja Ha
Atmos. Chem. Phys., 25, 705–726, https://doi.org/10.5194/acp-25-705-2025, https://doi.org/10.5194/acp-25-705-2025, 2025
Short summary
Short summary
This study attempts to test a general factor that explains differences in the properties of different mixed-phase clouds using a modeling tool. Although this attempt is not to identify a factor that can perfectly explain and represent the properties of different mixed-phase clouds, we believe that this attempt acts as a valuable stepping stone towards a more complete, general way of using climate models to better predict climate change.
Jeonggyu Kim, Sungmin Park, Greg M. McFarquhar, Anthony J. Baran, Joo Wan Cha, Kyoungmi Lee, Seoung Soo Lee, Chang Hoon Jung, Kyo-Sun Sunny Lim, and Junshik Um
Atmos. Chem. Phys., 24, 12707–12726, https://doi.org/10.5194/acp-24-12707-2024, https://doi.org/10.5194/acp-24-12707-2024, 2024
Short summary
Short summary
We developed idealized models to represent the shapes of ice particles found in deep convective clouds and calculated their single-scattering properties. By comparing these results with in situ measurements, we discovered that a mixture of shape models matches in situ measurements more closely than single-form models or aggregate models. This finding has important implications for enhancing the simulation of single-scattering properties of ice crystals in deep convective clouds.
Alexei Korolev, Zhipeng Qu, Jason Milbrandt, Ivan Heckman, Mélissa Cholette, Mengistu Wolde, Cuong Nguyen, Greg M. McFarquhar, Paul Lawson, and Ann M. Fridlind
Atmos. Chem. Phys., 24, 11849–11881, https://doi.org/10.5194/acp-24-11849-2024, https://doi.org/10.5194/acp-24-11849-2024, 2024
Short summary
Short summary
The phenomenon of high ice water content (HIWC) occurs in mesoscale convective systems (MCSs) when a large number of small ice particles with typical sizes of a few hundred micrometers is found at high altitudes. It was found that secondary ice production in the vicinity of the melting layer plays a key role in the formation and maintenance of HIWC. This study presents a conceptual model of the formation of HIWC in tropical MCSs based on in situ observations and numerical simulation.
Minseok Kim, Jhoon Kim, Hyunkwang Lim, Seoyoung Lee, Yeseul Cho, Yun-Gon Lee, Sujung Go, and Kyunghwa Lee
Atmos. Meas. Tech., 17, 4317–4335, https://doi.org/10.5194/amt-17-4317-2024, https://doi.org/10.5194/amt-17-4317-2024, 2024
Short summary
Short summary
Information about aerosol loading in the atmosphere can be collected from various satellite instruments. Aerosol products from various satellite instruments have their own error characteristics. This study statistically merged aerosol optical depth datasets from multiple instruments aboard geostationary satellites considering uncertainties. Also, a deep neural network technique is adopted for aerosol data merging.
Michie Vianca De Vera, Larry Di Girolamo, Guangyu Zhao, Robert M. Rauber, Stephen W. Nesbitt, and Greg M. McFarquhar
Atmos. Chem. Phys., 24, 5603–5623, https://doi.org/10.5194/acp-24-5603-2024, https://doi.org/10.5194/acp-24-5603-2024, 2024
Short summary
Short summary
Tropical oceanic low clouds remain a dominant source of uncertainty in cloud feedback in climate models due to their macrophysical properties (fraction, size, height, shape, distribution) being misrepresented. High-resolution satellite imagery over the Philippine oceans is used here to characterize cumulus macrophysical properties and their relationship to meteorological variables. Such information can act as a benchmark for cloud models and can improve low-cloud generation in climate models.
Bu-Yo Kim, Joo Wan Cha, and Yong Hee Lee
Atmos. Meas. Tech., 16, 5403–5413, https://doi.org/10.5194/amt-16-5403-2023, https://doi.org/10.5194/amt-16-5403-2023, 2023
Short summary
Short summary
A camera-based imager and convolutional neural network (CNN) were used to estimate ground cloud cover. Image data from 2019 were used for training and validation, and those from 2020 were used for testing. The CNN model exhibited high performance, with an accuracy of 0.92, RMSE of 1.40 tenths, and 93% agreement with observed cloud cover within ±2 tenths' difference. It also outperformed satellites and ceilometers and proved to be the most suitable for ground-based cloud cover estimation.
Calvin Howes, Pablo E. Saide, Hugh Coe, Amie Dobracki, Steffen Freitag, Jim M. Haywood, Steven G. Howell, Siddhant Gupta, Janek Uin, Mary Kacarab, Chongai Kuang, L. Ruby Leung, Athanasios Nenes, Greg M. McFarquhar, James Podolske, Jens Redemann, Arthur J. Sedlacek, Kenneth L. Thornhill, Jenny P. S. Wong, Robert Wood, Huihui Wu, Yang Zhang, Jianhao Zhang, and Paquita Zuidema
Atmos. Chem. Phys., 23, 13911–13940, https://doi.org/10.5194/acp-23-13911-2023, https://doi.org/10.5194/acp-23-13911-2023, 2023
Short summary
Short summary
To better understand smoke properties and its interactions with clouds, we compare the WRF-CAM5 model with observations from ORACLES, CLARIFY, and LASIC field campaigns in the southeastern Atlantic in August 2017. The model transports and mixes smoke well but does not fully capture some important processes. These include smoke chemical and physical aging over 4–12 days, smoke removal by rain, sulfate particle formation, aerosol activation into cloud droplets, and boundary layer turbulence.
Jiyeon Park, Hyojin Kang, Yeontae Gim, Eunho Jang, Ki-Tae Park, Sangjong Park, Chang Hoon Jung, Darius Ceburnis, Colin O'Dowd, and Young Jun Yoon
Atmos. Chem. Phys., 23, 13625–13646, https://doi.org/10.5194/acp-23-13625-2023, https://doi.org/10.5194/acp-23-13625-2023, 2023
Short summary
Short summary
We measured the number size distribution of 2.5–300 nm particles and cloud condensation nuclei (CCN) number concentrations at King Sejong Station on the Antarctic Peninsula continuously from 1 January to 31 December 2018. During the pristine and clean periods, 97 new particle formation (NPF) events were detected. For 83 of these, CCN concentrations increased by 2 %–268 % (median 44 %) following 1 to 36 h (median 8 h) after NPF events.
Rose Marie Miller, Robert M. Rauber, Larry Di Girolamo, Matthew Rilloraza, Dongwei Fu, Greg M. McFarquhar, Stephen W. Nesbitt, Luke D. Ziemba, Sarah Woods, and Kenneth Lee Thornhill
Atmos. Chem. Phys., 23, 8959–8977, https://doi.org/10.5194/acp-23-8959-2023, https://doi.org/10.5194/acp-23-8959-2023, 2023
Short summary
Short summary
The influence of human-produced aerosols on clouds remains one of the uncertainties in radiative forcing of Earth’s climate. Measurements of aerosol chemistry from sources around the Philippines illustrate the linkage between aerosol chemical composition and cloud droplet characteristics. Differences in aerosol chemical composition in the marine layer from biomass burning, industrial, ship-produced, and marine aerosols are shown to impact cloud microphysical structure just above cloud base.
Jincheol Park, Jia Jung, Yunsoo Choi, Hyunkwang Lim, Minseok Kim, Kyunghwa Lee, Yun Gon Lee, and Jhoon Kim
Atmos. Meas. Tech., 16, 3039–3057, https://doi.org/10.5194/amt-16-3039-2023, https://doi.org/10.5194/amt-16-3039-2023, 2023
Short summary
Short summary
In response to the recent release of new geostationary platform-derived observational data generated by the Geostationary Environment Monitoring Spectrometer (GEMS) and its sister instruments, this study utilized the GEMS data fusion product and its proxy data in adjusting aerosol precursor emissions over East Asia. The use of spatiotemporally more complete observation references in updating the emissions resulted in more promising model performances in estimating aerosol loadings in East Asia.
Ruhi S. Humphries, Melita D. Keywood, Jason P. Ward, James Harnwell, Simon P. Alexander, Andrew R. Klekociuk, Keiichiro Hara, Ian M. McRobert, Alain Protat, Joel Alroe, Luke T. Cravigan, Branka Miljevic, Zoran D. Ristovski, Robyn Schofield, Stephen R. Wilson, Connor J. Flynn, Gourihar R. Kulkarni, Gerald G. Mace, Greg M. McFarquhar, Scott D. Chambers, Alastair G. Williams, and Alan D. Griffiths
Atmos. Chem. Phys., 23, 3749–3777, https://doi.org/10.5194/acp-23-3749-2023, https://doi.org/10.5194/acp-23-3749-2023, 2023
Short summary
Short summary
Observations of aerosols in pristine regions are rare but are vital to constraining the natural baseline from which climate simulations are calculated. Here we present recent seasonal observations of aerosols from the Southern Ocean and contrast them with measurements from Antarctica, Australia and regionally relevant voyages. Strong seasonal cycles persist, but striking differences occur at different latitudes. This study highlights the need for more long-term observations in remote regions.
Seoung Soo Lee, Junshik Um, Won Jun Choi, Kyung-Ja Ha, Chang Hoon Jung, Jianping Guo, and Youtong Zheng
Atmos. Chem. Phys., 23, 273–286, https://doi.org/10.5194/acp-23-273-2023, https://doi.org/10.5194/acp-23-273-2023, 2023
Short summary
Short summary
This paper elaborates on process-level mechanisms regarding how the interception of radiation by aerosols interacts with the surface heat fluxes and atmospheric instability in warm cumulus clouds. This paper elucidates how these mechanisms vary with the location or altitude of an aerosol layer. This elucidation indicates that the location of aerosol layers should be taken into account for parameterizations of aerosol–cloud interactions.
Paul A. Barrett, Steven J. Abel, Hugh Coe, Ian Crawford, Amie Dobracki, James Haywood, Steve Howell, Anthony Jones, Justin Langridge, Greg M. McFarquhar, Graeme J. Nott, Hannah Price, Jens Redemann, Yohei Shinozuka, Kate Szpek, Jonathan W. Taylor, Robert Wood, Huihui Wu, Paquita Zuidema, Stéphane Bauguitte, Ryan Bennett, Keith Bower, Hong Chen, Sabrina Cochrane, Michael Cotterell, Nicholas Davies, David Delene, Connor Flynn, Andrew Freedman, Steffen Freitag, Siddhant Gupta, David Noone, Timothy B. Onasch, James Podolske, Michael R. Poellot, Sebastian Schmidt, Stephen Springston, Arthur J. Sedlacek III, Jamie Trembath, Alan Vance, Maria A. Zawadowicz, and Jianhao Zhang
Atmos. Meas. Tech., 15, 6329–6371, https://doi.org/10.5194/amt-15-6329-2022, https://doi.org/10.5194/amt-15-6329-2022, 2022
Short summary
Short summary
To better understand weather and climate, it is vital to go into the field and collect observations. Often measurements take place in isolation, but here we compared data from two aircraft and one ground-based site. This was done in order to understand how well measurements made on one platform compared to those made on another. Whilst this is easy to do in a controlled laboratory setting, it is more challenging in the real world, and so these comparisons are as valuable as they are rare.
Siddhant Gupta, Greg M. McFarquhar, Joseph R. O'Brien, Michael R. Poellot, David J. Delene, Ian Chang, Lan Gao, Feng Xu, and Jens Redemann
Atmos. Chem. Phys., 22, 12923–12943, https://doi.org/10.5194/acp-22-12923-2022, https://doi.org/10.5194/acp-22-12923-2022, 2022
Short summary
Short summary
The ability of NASA’s Terra and Aqua satellites to retrieve cloud properties and estimate the changes in cloud properties due to aerosol–cloud interactions (ACI) was examined. There was good agreement between satellite retrievals and in situ measurements over the southeast Atlantic Ocean. This suggests that, combined with information on aerosol properties, satellite retrievals of cloud properties can be used to study ACI over larger domains and longer timescales in the absence of in situ data.
Zhipeng Qu, Alexei Korolev, Jason A. Milbrandt, Ivan Heckman, Yongjie Huang, Greg M. McFarquhar, Hugh Morrison, Mengistu Wolde, and Cuong Nguyen
Atmos. Chem. Phys., 22, 12287–12310, https://doi.org/10.5194/acp-22-12287-2022, https://doi.org/10.5194/acp-22-12287-2022, 2022
Short summary
Short summary
Secondary ice production (SIP) is an important physical phenomenon that results in an increase in the cloud ice particle concentration and can have a significant impact on the evolution of clouds. Here, idealized simulations of a tropical convective system were conducted. Agreement between the simulations and observations highlights the impacts of SIP on the maintenance of tropical convection in nature and the importance of including the modelling of SIP in numerical weather prediction models.
Seoung Soo Lee, Jinho Choi, Goun Kim, Kyung-Ja Ha, Kyong-Hwan Seo, Chang Hoon Jung, Junshik Um, Youtong Zheng, Jianping Guo, Sang-Keun Song, Yun Gon Lee, and Nobuyuki Utsumi
Atmos. Chem. Phys., 22, 9059–9081, https://doi.org/10.5194/acp-22-9059-2022, https://doi.org/10.5194/acp-22-9059-2022, 2022
Short summary
Short summary
This study investigates how aerosols affect clouds and precipitation and how the aerosol effects vary with varying types of clouds that are characterized by cloud depth in two metropolitan areas in East Asia. As cloud depth increases, the enhancement of precipitation amount transitions to no changes in precipitation amount with increasing aerosol concentrations. This indicates that cloud depth needs to be considered for a comprehensive understanding of aerosol-cloud interactions.
Dongwei Fu, Larry Di Girolamo, Robert M. Rauber, Greg M. McFarquhar, Stephen W. Nesbitt, Jesse Loveridge, Yulan Hong, Bastiaan van Diedenhoven, Brian Cairns, Mikhail D. Alexandrov, Paul Lawson, Sarah Woods, Simone Tanelli, Sebastian Schmidt, Chris Hostetler, and Amy Jo Scarino
Atmos. Chem. Phys., 22, 8259–8285, https://doi.org/10.5194/acp-22-8259-2022, https://doi.org/10.5194/acp-22-8259-2022, 2022
Short summary
Short summary
Satellite-retrieved cloud microphysics are widely used in climate research because of their central role in water and energy cycles. Here, we provide the first detailed investigation of retrieved cloud drop sizes from in situ and various satellite and airborne remote sensing techniques applied to real cumulus cloud fields. We conclude that the most widely used passive remote sensing method employed in climate research produces high biases of 6–8 µm (60 %–80 %) caused by 3-D radiative effects.
Siddhant Gupta, Greg M. McFarquhar, Joseph R. O'Brien, Michael R. Poellot, David J. Delene, Rose M. Miller, and Jennifer D. Small Griswold
Atmos. Chem. Phys., 22, 2769–2793, https://doi.org/10.5194/acp-22-2769-2022, https://doi.org/10.5194/acp-22-2769-2022, 2022
Short summary
Short summary
This study evaluates the impact of biomass burning aerosols on precipitation in marine stratocumulus clouds using observations from the NASA ObseRvations of Aerosols above CLouds and their intEractionS (ORACLES) field campaign over the Southeast Atlantic. Instances of contact and separation between aerosol and cloud layers show polluted clouds have a lower precipitation rate and a lower precipitation susceptibility. This information will help improve cloud representation in Earth system models.
Yongjie Huang, Wei Wu, Greg M. McFarquhar, Ming Xue, Hugh Morrison, Jason Milbrandt, Alexei V. Korolev, Yachao Hu, Zhipeng Qu, Mengistu Wolde, Cuong Nguyen, Alfons Schwarzenboeck, and Ivan Heckman
Atmos. Chem. Phys., 22, 2365–2384, https://doi.org/10.5194/acp-22-2365-2022, https://doi.org/10.5194/acp-22-2365-2022, 2022
Short summary
Short summary
Numerous small ice crystals in tropical convective storms are difficult to detect and could be potentially hazardous for commercial aircraft. Previous numerical simulations failed to reproduce this phenomenon and hypothesized that key microphysical processes are still lacking in current models to realistically simulate the phenomenon. This study uses numerical experiments to confirm the dominant role of secondary ice production in the formation of these large numbers of small ice crystals.
Matthew W. Christensen, Andrew Gettelman, Jan Cermak, Guy Dagan, Michael Diamond, Alyson Douglas, Graham Feingold, Franziska Glassmeier, Tom Goren, Daniel P. Grosvenor, Edward Gryspeerdt, Ralph Kahn, Zhanqing Li, Po-Lun Ma, Florent Malavelle, Isabel L. McCoy, Daniel T. McCoy, Greg McFarquhar, Johannes Mülmenstädt, Sandip Pal, Anna Possner, Adam Povey, Johannes Quaas, Daniel Rosenfeld, Anja Schmidt, Roland Schrödner, Armin Sorooshian, Philip Stier, Velle Toll, Duncan Watson-Parris, Robert Wood, Mingxi Yang, and Tianle Yuan
Atmos. Chem. Phys., 22, 641–674, https://doi.org/10.5194/acp-22-641-2022, https://doi.org/10.5194/acp-22-641-2022, 2022
Short summary
Short summary
Trace gases and aerosols (tiny airborne particles) are released from a variety of point sources around the globe. Examples include volcanoes, industrial chimneys, forest fires, and ship stacks. These sources provide opportunistic experiments with which to quantify the role of aerosols in modifying cloud properties. We review the current state of understanding on the influence of aerosol on climate built from the wide range of natural and anthropogenic laboratories investigated in recent decades.
Seoung Soo Lee, Kyung-Ja Ha, Manguttathil Gopalakrishnan Manoj, Mohammad Kamruzzaman, Hyungjun Kim, Nobuyuki Utsumi, Youtong Zheng, Byung-Gon Kim, Chang Hoon Jung, Junshik Um, Jianping Guo, Kyoung Ock Choi, and Go-Un Kim
Atmos. Chem. Phys., 21, 16843–16868, https://doi.org/10.5194/acp-21-16843-2021, https://doi.org/10.5194/acp-21-16843-2021, 2021
Short summary
Short summary
Using a modeling framework, a midlatitude stratocumulus cloud system is simulated. It is found that cloud mass in the system becomes very low due to interactions between ice and liquid particles compared to that in the absence of ice particles. It is also found that interactions between cloud mass and aerosols lead to a reduction in cloud mass in the system, and this is contrary to an aerosol-induced increase in cloud mass in the absence of ice particles.
Bu-Yo Kim, Joo Wan Cha, and Ki-Ho Chang
Atmos. Meas. Tech., 14, 6695–6710, https://doi.org/10.5194/amt-14-6695-2021, https://doi.org/10.5194/amt-14-6695-2021, 2021
Short summary
Short summary
This study investigates a method for 24 h cloud cover calculation using a camera-based imager and supervised machine learning methods. The cloud cover is calculated by learning the statistical characteristics of the ratio, difference, and luminance using RGB channels of the image with a machine learning model. The proposed approach is suitable for nowcasting because it has higher learning and prediction speed than the method in which the many pixels of a 2D image are learned.
Rose M. Miller, Greg M. McFarquhar, Robert M. Rauber, Joseph R. O'Brien, Siddhant Gupta, Michal Segal-Rozenhaimer, Amie N. Dobracki, Arthur J. Sedlacek, Sharon P. Burton, Steven G. Howell, Steffen Freitag, and Caroline Dang
Atmos. Chem. Phys., 21, 14815–14831, https://doi.org/10.5194/acp-21-14815-2021, https://doi.org/10.5194/acp-21-14815-2021, 2021
Short summary
Short summary
A large stratocumulus cloud deck resides off the west coast of central Africa. Biomass burning in Africa produces a large plume of aerosol that is carried by the wind over this stratocumulus cloud deck. This paper shows that particles with sizes from 0.01 to 1 mm reside within this plume. Past studies have shown that biomass burning produces such particles, but this is the first study to show that they can be transported westward, over long distances, to the Atlantic stratocumulus cloud deck.
Ruhi S. Humphries, Melita D. Keywood, Sean Gribben, Ian M. McRobert, Jason P. Ward, Paul Selleck, Sally Taylor, James Harnwell, Connor Flynn, Gourihar R. Kulkarni, Gerald G. Mace, Alain Protat, Simon P. Alexander, and Greg McFarquhar
Atmos. Chem. Phys., 21, 12757–12782, https://doi.org/10.5194/acp-21-12757-2021, https://doi.org/10.5194/acp-21-12757-2021, 2021
Short summary
Short summary
The Southern Ocean region is one of the most pristine in the world and serves as an important proxy for the pre-industrial atmosphere. Improving our understanding of the natural processes in this region is likely to result in the largest reductions in the uncertainty of climate and earth system models. In this paper we present a statistical summary of the latitudinal gradient of aerosol and cloud condensation nuclei concentrations obtained from five voyages spanning the Southern Ocean.
Yongjie Huang, Wei Wu, Greg M. McFarquhar, Xuguang Wang, Hugh Morrison, Alexander Ryzhkov, Yachao Hu, Mengistu Wolde, Cuong Nguyen, Alfons Schwarzenboeck, Jason Milbrandt, Alexei V. Korolev, and Ivan Heckman
Atmos. Chem. Phys., 21, 6919–6944, https://doi.org/10.5194/acp-21-6919-2021, https://doi.org/10.5194/acp-21-6919-2021, 2021
Short summary
Short summary
Numerous small ice crystals in the tropical convective storms are difficult to detect and could be potentially hazardous for commercial aircraft. This study evaluated the numerical models against the airborne observations and investigated the potential cloud processes that could lead to the production of these large numbers of small ice crystals. It is found that key microphysical processes are still lacking or misrepresented in current numerical models to realistically simulate the phenomenon.
Cited articles
Albanesi, M. G. and Ferretti, M.: A space saving approach to the Hough
transform, 10th Int. Conf. on Pattern Recognition, Atlantic City, NJ, USA,
https://doi.org/10.1109/ICPR.1990.119403, 1990.
Atherton, T. J. and Kerbyson, D. J.: Size invariant circle detection, Image
Vision Comput, 17, 795–803, 1999.
Bailey, M. P. and Hallett, J.: Growth rates and habits of ice crystals
between −20 ∘C and −70 ∘C, J. Atmos. Sci., 61,
514–544, 2004.
Bailey, M. P. and Hallett, J.: A comprehensive habit diagram for atmospheric
ice crystals: Confirmation from the laboratory, AIRS II, and other field
studies, J. Atmos. Sci., 66, 2888–2899, 2009.
Baran, A. J., Gayet, J.-F., and Shcherbakov, V.: On the interpretation of an
unusual in-situ measured ice crystal scattering phase function, Atmos. Chem.
Phys., 12, 9355–9364, https://doi.org/10.5194/acp-12-9355-2012, 2012.
Barth, M. C., Cantrell, C. A., Brune, W. H., Rutledge, S. A., Crawford, J.
H., Huntrieser, H., Carey, L. D., MacGorman, D., Weisman, M., Pickering, K.
E., Bruning, E., Anderson, B., Apel, E., Biggerstaff, M., Campos, T.,
Campuzano-Jost, P., Cohen, R., Crounse, J., Day, D. A., Diskin, G., Flocke,
F., Fried, A., Garland, C., Heikes, B., Honomichi, S., Hornbrook, R., Huey,
L. G., Jimenez, J., Lang, T., Lichtenstern, M., Mikoviny, T., Nault, B.,
O'Sullivan, D., Pan, L., Peischl, J., Pollack, I., Richter, D., Riemer, D.,
Ryerson, T., Schlager, H., St. Clair, J., Walega, J., Weibring, P.,
Weinheimer, A., Wennberg, P., Wisthaler, A., Wooldridge, P., and Zeigler, C.:
The Deep Convective clouds and Chemistry (DC3) Field Campaign, B. Am.
Meteorol. Soc., 96, 1281–1309, https://doi.org/10.1175/BAMS-D-13-00290.1, 2015.
Bescond, A., Yon, J., Ouf, F. X., Ferry, D., Delhaye, D., Gaffié, D.,
Coppalle, A., and Rozé, C.: Automated determination of aggregate primary
particle size distribution by TEM image analysis: Application to soot,
Aerosol Sci. Tech., 48, 831–841, 2014.
Bony, S., Stevens, B., Frierson, D. M. W., Jakob, C., Kageyama, M., Pincus,
R., Shepherd, T. G., Sherwood, S. C., Siebesma, A. P., Sobel, A. H.,
Watanabe, M., and Webb, M. J.: Clouds, circulation and climate sensitivity,
Nat. Geosci., 8, 261–268, https://doi.org/10.1038/ngeo2398, 2015.
Bony, S., Stevens, B., Coppin, D., Becker, T., Reed, K. A., Voigt, A., and
Medeiros, B.: Thermodynamic control of anvil cloud amount, P. Natl. Acad.
Sci. USA, 113, 8927–8932, 2016.
Chakrabarty, R. K., Moosmüller, H., Garro, M. A., Arnott, W. P., Walker,
J., Susott, R. A., Babbitt, R. E., Wold, C. E., Lincoln, E. N., and Hao, W.
M.: Emissions from the laboratory combustion of wildland fuels: Particle
morphology and size, J. Geophys. Res., 111, D07204, https://doi.org/10.1029/2005JD006659,
2006.
China, S., Mazzoleni, C., Gorkowski, K., Aiken, A. C., and Dubey, M. K.:
Morphology and mixing state of individual freshly emitted wildfire
carbonaceous particles, Nat. Commun, 4, 2122, https://doi.org/10.1038/ncomms3122, 2013.
Connolly, P. J., Saunders, C. P. R., Gallagher, M. W., Bower, K. N., Flynn,
M. J., Choularton, T. W., Whiteway, J., and Lawson, R. P.: Aircraft
observations of the influence of electric fields on the aggregation of ice
crystals, Q. J. Roy. Meteor. Soc., 131, 1695–1712, https://doi.org/10.1256/qj.03.217,
2005.
Conolly, P. J., Flynn, M. J., Ulanowski, Z., Choularton, T. W., Gallagher, M.
W., and Bower, K. N.: Calibration of cloud particle imager probes using
calibration beads and ice crystal analogs: The depth of field, J. Atmos.
Ocean. Tech., 24, 1860–1879, 2007.
de Reus, M., Borrmann, S., Bansemer, A., Heymsfield, A. J., Weigel, R.,
Schiller, C., Mitev, V., Frey, W., Kunkel, D., Kürten, A., Curtius, J.,
Sitnikov, N. M., Ulanovsky, A., and Ravegnani, F.: Evidence for ice particles
in the tropical stratosphere from in-situ measurements, Atmos. Chem. Phys.,
9, 6775–6792, https://doi.org/10.5194/acp-9-6775-2009, 2009.
Duda, R. O. and Hart, P. E.: Use of the Hough transformation to detect lines
and curves in pictures, Communication of the ACM, 15, 11–15, 1972.
Feng, Z., Dong, X., Xi, B., Schumacher, C., Minnis, P., and Khaiyer, M.:
Top-of-atmosphere radiation budget of convective core/stratiform rain and
anvil clouds from deep convective systems, J. Geophys. Res., 116, D23202,
https://doi.org/10.1029/2011JD016451, 2011.
Feng, Z., Dong, X., Xi, B., McFarlane, S. A., Kennedy, A., Lin, B., and
Minnis, P.: Life cycle of midlatitude deep convective systems in a Lagrangian
framework, J. Geophys. Res., 117, D23201, https://doi.org/10.1029/2012JD018362, 2012.
Field, P. R., Wood, R., Brown, P. R. A., Kay, P. H., Hirst, E., Greenaway,
R., and Smith, J. A.: Ice Particle Interarrival Times Measured with a Fast
FSSP, J. Atmos. Ocean. Tech., 20, 249–261, 2003.
Field, P. R., Heymsfield, A. J., and Bansemer, A.: Shattering and particle
interarrival times measured by optical array probes in ice clouds, J. Atmos.
Ocean. Tech., 23, 1357–1371, 2006.
Frey, W., Borrmann, S., Kunkel, D., Weigel, R., de Reus, M., Schlager, H.,
Roiger, A., Voigt, C., Hoor, P., Curtius, J., Krämer, M., Schiller, C.,
Volk, C. M., Homan, C. D., Fierli, F., Di Donfrancesco, G., Ulanovsky, A.,
Ravegnani, F., Sitnikov, N. M., Viciani, S., D'Amato, F., Shur, G. N.,
Belyaev, G. V., Law, K. S., and Cairo, F.: In situ measurements of tropical
cloud properties in the West African Monsoon: upper tropospheric ice clouds,
Mesoscale Convective System outflow, and subvisual cirrus, Atmos. Chem.
Phys., 11, 5569–5590, https://doi.org/10.5194/acp-11-5569-2011, 2011.
Frey, W., Schofield, R., Hoor, P., Kunkel, D., Ravegnani, F., Ulanovsky, A.,
Viciani, S., D'Amato, F., and Lane, T. P.: The impact of overshooting deep
convection on local transport and mixing in the tropical upper
troposphere/lower stratosphere (UTLS), Atmos. Chem. Phys., 15, 6467–6486,
https://doi.org/10.5194/acp-15-6467-2015, 2015.
Fu, Q., Krueger, S., and Liou, K.: Interactions of radiation and convection
in simulated tropical cloud clusters, J. Atmos. Sci., 52, 1310–1328, 1995.
Gallagher, M. W., Connolly, P. J., Whiteway, J., Figueras-Nieto, D., Flynn,
M., Choularton, T. W., Bower, K. N., Cook, C., Busen, R., and Hacker, J.: An
overview of the microphysical structure of cirrus clouds observed during
EMERALD-1, Q. J. Roy. Meteor. Soc., 131, 1143–1169, 2005.
Gallagher, M. W., Connolly, P. J., Crawford, I., Heymsfield, A., Bower, K.
N., Choularton, T. W., Allen, G., Flynn, M. J., Vaughan, G., and Hacker, J.:
Observations and modelling of microphysical variability, aggregation and
sedimentation in tropical anvil cirrus outflow regions, Atmos. Chem. Phys.,
12, 6609–6628, https://doi.org/10.5194/acp-12-6609-2012, 2012.
Gayet, J.-F., Mioche, G., Bugliaro, L., Protat, A., Minikin, A., Wirth, M.,
Dörnbrack, A., Shcherbakov, V., Mayer, B., Garnier, A., and Gourbeyre,
C.: On the observation of unusual high concentration of small chain-like
aggregate ice crystals and large ice water contents near the top of a deep
convective cloud during the CIRCLE-2 experiment, Atmos. Chem. Phys., 12,
727–744, https://doi.org/10.5194/acp-12-727-2012, 2012.
Hartmann, D. L.: Tropical anvil clouds and climate sensitivity, P. Natl.
Acad. Sci. USA, 113, 8897–8899, 2016.
Hartmann, D. L. and Berry, S. E.: The balanced radiative effect of tropical
anvil clouds, J. Geophys. Res.-Atmos., 122, 5003–5020,
https://doi.org/10.1002/2017JD026460, 2017.
Heinson, W. R. and Chakrabarty, R. K.: Fractal morphology of black carbon
aerosol enhances absorption in the thermal infrared wavelengths, Opt. Lett.,
41, 808–811, 2016.
Heinson, W. R., Sorensen, C. M., and Chakrabarti, A.: A three parameter
description of the structure of diffusion limited cluster fractal aggregates,
J. Colloid Interf. Sci., 375, 65–69, https://doi.org/10.1016/j.jcis.2012.01.062, 2012.
Heymsfield, A. J.: Ice particle evolution in the anvil of a severe
thunderstorm during CCOPE, J. Atmos. Sci., 43, 2463–2478, 1986.
Heymsfield, A. J. and Sabin, R. M.: Cirrus crystal nucleation by homogeneous
freezing of solution droplets, J. Atmos. Sci., 46, 2252–2264, 1989.
Heymsfield, A. J., Miloshevich, L., Schmitt, C., Bansemer, A., Twohy, C.,
Poellot, M., Fridlind, A., and Gerber, H.: Homogeneous ice nucleation in
subtropical and tropical convection and its influence on cirrus anvil
microphysics, J. Atmos. Sci., 62, 41–64, https://doi.org/10.1175/JAS-3360.1, 2005.
Heymsfield, A. J., Bansemer, A., Heymsfield, G., and Fierro, A. O.:
Microphysics of maritime tropical convective updrafts at temperatures from
−20 to −60 ∘C, J. Atmos. Sci., 66, 3530–3562, 2009.
Homeyer, C. R., Pan, L. L., and Barth, M. C.: Transport from convective
overshooting of the extratropical tropopause and the role of large-scale
lower stratosphere stability, J. Geophys. Res.-Atmos., 119, 2220–2240,
https://doi.org/10.1002/2013JD020931, 2014.
Hough, P. V. C.: Method and means for recognizing complex patterns,
18 December, U.S. Patent 3.069.654, 1962.
Jackson, R. C. and McFarquhar, G. M.: An Assessment of the Impact of
Antishattering Tips and Artifact Removal Techniques on Bulk Cloud Ice
Microphysical and Optical Properties Measured by the 2D Cloud Probe, J.
Atmos. Ocean. Tech., 30, 2131–2144, 2014.
Jackson, R. C., McFarquhar, G. M., Stith, J., Beals, M., Shaw, R. A., Jensen,
J., Fugal, J., and Korolev, A.: An Assessment of the Impact of Antishattering
Tips and Artifact Removal Techniques on Cloud Ice Size Distributions Measured
by the 2D Cloud Probe, J. Atmos. Ocean. Tech., 31, 2576–2590, 2014.
Järvinen, E., Schnaiter, M., Mioche, G., Jourdan, O., Shcherbakov, V. N.,
Costa, A., Afchine, A., Krämer, M., Heidelberg, F., Jurkat, T., Voigt,
C., Schlager, H., Nichman, L., Gallagher, M., Hirst, E., Schmitt, C.,
Bansemer, A., Heymsfield, A., Lawson, P., Tricoli, U., Pfeilsticker, K.,
Vochezer, P., Möhler, O., and Leisner, T.: Quasi-Spherical Ice in
Convective Clouds, J. Atmos. Sci., 73, 3885–3910,
https://doi.org/10.1175/JAS-D-15-0365.1, 2016.
Jensen, E. J., Toon, O. B., Selkirk, H. B., Spinhirne, J. D., and Schoeberl,
M. R.: On the formation and persistence of subvisible cirrus clouds near the
tropical tropopause, J. Geophys. Res., 101, 21361–21375,
https://doi.org/10.1029/95JD03575, 1996.
Jensen, E. J., Lawson, P., Baker, B., Pilson, B., Mo, Q., Heymsfield, A. J.,
Bansemer, A., Bui, T. P., McGill, M., Hlavka, D., Heymsfield, G., Platnick,
S., Arnold, G. T., and Tanelli, S.: On the importance of small ice crystals
in tropical anvil cirrus, Atmos. Chem. Phys., 9, 5519–5537,
https://doi.org/10.5194/acp-9-5519-2009, 2009.
Jensen, M. P., Petersen, W. A., Bansemer, A., Bharadwaj, N., Carey, L. D.,
Cecil, D. J., Collis, S. M., Del Genio, A. D., Dolan, B., Gerlach, J.,
Giangrande, S. E., Heymsfield, A., Heymsfield, G., Kollias, P., Lang, T. J.,
Nesbitt, S. W., Neumann, A., Poellot, M., Rutledge, S. A., Schwaller, M.,
Tokay, A., Williams, C. R., Wolff, D. B., Xie, S., and Zipser, E. J.: The
Midlatitude Continental Convective Clouds Experiment (MC3E), B. Am. Meteorol.
Soc., 97, 1667–1686, https://doi.org/10.1175/BAMS-D-14-00228.1, 2016.
Kolb, M., Botet, R., and Jullien, R.: Scaling of kinetically growing
clusters, Phys. Rev. Lett., 51, 1123–1126, 1983.
Korolev, A. and Field, P. R.: Assessment of the performance of the
inter-arrival time algorithm to identify ice shattering artifacts in cloud
particle probe measurements, Atmos. Meas. Tech., 8, 761–777,
https://doi.org/10.5194/amt-8-761-2015, 2015.
Korolev, A. V., Emery, E. F., Strapp, J. W., Cober, S. G., Isaac, G. A.,
Wasey, M., and Marcotte, D.: Small Ice Particles in Tropospheric Clouds: Fact
or Artifact?, B. Am. Meteorol. Soc., 92, 967–973, 2011.
Köylü, Ü. Ö., Faeth, G. M., Farias, T. L., and Carvalho, M.
G.: Fractal and projected structure properties of soot aggregates, Combust.
Flame, 100, 621–623, 1995.
Lattuada, M., Wu, H., and Morbidelli, M.: Hydrodynamic radius of fractal
clusters, J. Colloid. Interf. Sci., 268, 96–105, 2003.
Lawson, R. P.: Effects of ice particles shattering on the 2D-S probe, Atmos.
Meas. Tech., 4, 1361–1381, https://doi.org/10.5194/amt-4-1361-2011, 2011.
Lawson, R. P., Baker, B. A., and Pilson, B. L.: In-Situ measurements of
microphysical properties of mid-latitude and anvil cirrus, Proceedings, 30th
International Symposium on Remote Sensing of Environment, November, Honolulu,
Hawaii, 707–710, 2003.
Lawson, R. P., Jensen, E., Mitchell, D. L., Baker, B., Mo, Q., and Pilson,
B.: Microphysical and radiative properties of tropical clouds investigated in
TC4 and NAMMA, J. Geophys. Res., 115, D00J08, https://doi.org/10.1029/2009JD013017, 2010.
Lewis, K. A., Arnott, W. P., Moosmüller, H., Chakrabarty, R. K., Carrico,
C. M., Kreidenweis, S. M., Day, D. E., Malm, W. C., Laskin, A., Jimenez, J.
L., Ulbrich, I. M., Huffman, J. A., Onasch, T. B., Trimborn, A., Liu, L., and
Mishchenko, M. I.: Reduction in biomass burning aerosol light absorption upon
humidification: roles of inorganically-induced hygroscopicity, particle
collapse, and photoacoustic heat and mass transfer, Atmos. Chem. Phys., 9,
8949–8966, https://doi.org/10.5194/acp-9-8949-2009, 2009.
Li, H., Lavin, M. A., and Le Master, R. J.: Fast Hough transform: A
hierarchical approach, Lect. Notes Comput. Sc., 36, 139–161, 1986.
Lilly, D. K.: Cirrus outflow dynamics, J. Atmos. Sci., 45, 1594–1605, 1988.
Liu, L., Mishchenko, M. I., and Arnott, W. P.: A study of radiative
properties of fractal soot aggregates using the superposition T-matrix
method, J. Quant. Spectrosc. Ra., 109, 2656–2663, 2008.
Mandelbrot, B.: The Fractal Geometry of Nature, W. H. Freeman and Company,
New York, 468 pp., 1982.
May, P. T., Mather, J. H., Vaughan, G., Jakob, C., McFarquhar, G. M., Bower,
K. N., and Mace, G. G.: The tropical warm pool international cloud
experiment, B. Am. Meteorol. Soc., 89, 629–645, 2008.
McFarquhar, G. M. and Heymsfield, A. J.: Microphysical characteristics of
three anvils sampled during the Central Equatorial Pacific Experiment, J.
Atmos. Sci., 53, 2401–2423, 1996.
McFarquhar, G. M., Heymsfield, A. J., Macke, A., Iaquinta, J., and Aulenbach,
S. M.: Use of observed ice crystal sizes and shapes to calculate
mean-scattering properties and multispectral radiances: CEPEX April 4, 1993,
case study, J. Geophys. Res., 104, 31763–31779, 1999.
McFarquhar, G. M., Yang, P., Macke, A., and Baran, A. J.: A new
parameterization of single scattering solar radiative properties for tropical
anvils using observed ice crystal size and shape distributions, J. Atmos.
Sci., 59, 2458–2478, 2002.
McFarquhar, G. M., Um, J., Freer, M., Baumgardner, D., Kok, G. L., and Mace,
G.: Importance of small ice crystals to cirrus properties: Observations from
the Tropical Warm Pool International Cloud Experiment (TWP-ICE), Geophys.
Res. Lett., 34, L13803, https://doi.org/10.1029/2007GL029865, 2007.
McFarquhar, G. M., Um, J., and Jackson, R.: Small cloud particle shapes in
mixed-phase clouds, J. Appl. Meteorol. Clim., 52, 1277–1293, 2013.
McFarquhar, G. M., Baumgardner, D., Bansemer, A., Abel, S. J., Crosier, J.,
French, J., Rosenberg, P., Korolev, A., Schwarzoenboeck, A., Leroy, D., Um,
J., Wu, W., Heymsfield, A. J., Twohy, C., Detwiler, A., Field, P., Neumann,
A., Cotton, R., Axisa, D., and Dong, J.: Processing of ice cloud in-situ data
collected by bulk water, scattering, and imaging probes: Fundamentals,
uncertainties, and efforts towards consistency, Meteor. Mon., 58,
11.1–11.33, https://doi.org/10.1175/AMSMONOGRAPHS-D-16-0007.1, 2017.
Meakin, P.: Formation of fractal clusters and networks by irreversible
diffusion-limited aggregation, Phys. Rev. Lett., 51, 1119–1122, 1983.
Mirzaei, M. and Rafsanjani, H. K.: An automatic algorithm for determination
of the nanoparticles from TEM images using circular Hough transform, Micron,
96, 86–95, 2017.
Nousiainen, T. and McFarquhar, G. M.: Light scattering by quasi–spherical
ice crystals, J. Atmos. Sci., 61, 2229–2248, 2004.
Nousiainen, T., Lindqvist, H., McFarquhar, G. M., and Um, J.: Small irregular
ice crystals in tropical cirrus, J. Atmos. Sci., 68, 2614–2627,
https://doi.org/10.1175/2011JAS3733.1, 2011.
Pedernera, D. A. and Ávila, E. E.: Frozen-droplets aggregation at
temperature below −40 ∘C, J. Geophys. Res., 123, 1244–1252, 2018.
Phillips, V. T. J., Donner, L. J., and Garner, S. T.: Nucleation processes in
deep convection simulated by a cloud-system-resolving model with
double-moment bulk microphysics, J. Atmos. Sci., 64, 738–761, 2007.
Pierce, F., Sorensen, C. M., and Chakrabarti, A.: Computer simulation of
diffusion-limited cluster aggregation with an Epstein drag force, Phys. Rev.
E, 74, 021411, https://doi.org/10.1103/PhysRevE.74.021411, 2006.
Proud, S. R.: Analysis of overshooting top detections by Meteosat Second
Generation: A 5-year dataset, Q. J. Roy. Meteor. Soc., 141, 909–915,
https://doi.org/10.1002/qj.2410, 2015.
Rosenfeld, D. and Woodley, W.: Deep convective clouds with sustained
superooled liquid water down to −37.5 ∘C, Nature, 405, 440–442,
https://doi.org/10.1038/35013030, 2000.
Saunders, C. P. R. and Wahab, N. M. A.: The influence of electric fields on
the aggregation of ice crystals, J. Meteorol. Soc. Jpn., 53, 121–126, 1975.
Sorensen, C. M.: Light scattering by fractal aggregates: A review, Aerosol
Sci. Tech., 35, 648–687, 2001.
Sorensen, C. M. and Roberts, G. C.: The prefactor of fractal aggregates, J.
Colloid Interf. Sci., 186, 447–452, 1997.
Stephens, G. L.: Cloud feedbacks in the climate system: A critical review, J.
Climate, 18, 237–273, 2005.
Stephens, G. L., Tsay, S. C., Stackhouse, P. W., and Flatau, P. J.: The
relevance of the microphysical and radiative properties of cirrus clouds to
climate and climatic feedback, J. Atmos. Sci., 47, 1742–1753,
https://doi.org/10.1175/1520-0469(1990)047<1742:trotma>2.0.co;2, 1990.
Stith, J. L., Dye, J. E., Bansemer, A., Heymsfield, A. J., Grainger, C. A.,
Petersen, W. A., and Cifelli, R.: Microphysical Observations of Tropical
Clouds, J. Appl. Meteorol., 41, 97–117,
https://doi.org/10.1175/1520-0450(2002)041<0097:MOOTC>2.0.CO;2, 2002.
Stith, J. L., Haggerty, J. A., Heymsfield, A., and Grainger, C. A.:
Microphysical Characteristics of Tropical Updrafts in Clean Conditions, J.
Appl. Meteorol., 43, 779–794, https://doi.org/10.1175/2104.1, 2004.
Stith, J. L., Avallone, L. M., Bansemer, A., Basarab, B., Dorsi, S. W.,
Fuchs, B., Lawson, R. P., Rogers, D. C., Rutledge, S., and Toohey, D. W.: Ice
particles in the upper anvil regions of midlatitude continental
thunderstorms: the case for frozen-drop aggregates, Atmos. Chem. Phys., 14,
1973–1985, https://doi.org/10.5194/acp-14-1973-2014, 2014.
Stith, J. L., Basarab, B., Rutledge, S. A., and Weinheimer, A.: Anvil
microphysical signatures associated with lightning-produced
NOx, Atmos. Chem. Phys., 16, 2243–2254,
https://doi.org/10.5194/acp-16-2243-2016, 2016.
Taylor, J. W., Choularton, T. W., Blyth, A. M., Liu, Z., Bower, K. N.,
Crosier, J., Gallagher, M. W., Williams, P. I., Dorsey, J. R., Flynn, M. J.,
Bennett, L. J., Huang, Y., French, J., Korolev, A., and Brown, P. R. A.:
Observations of cloud microphysics and ice formation during COPE, Atmos.
Chem. Phys., 16, 799–826, https://doi.org/10.5194/acp-16-799-2016, 2016.
UCAR/NCAR (Earth Observing Laboratory): NSF/NCAR GV (HIAPER) 3V-CPI Raw CPI
ROI Imagery, Version 1.0, UCAR/NCAR – Earth Observing Laboratory,
https://doi.org/10.5065/D6S180T6, 2013.
UCAR/NCAR (Earth Observing Laboratory): Low Rate (LRT – 1 sps) Navigation,
State Parameter, and Microphysics Flight-Level Data (NetCDF), Version 2.0,
UCAR/NCAR – Earth Observing Laboratory, https://doi.org/10.5065/D6BC3WKB, 2017.
Um, J. and McFarquhar, G. M.: Single-scattering properties of aggregates of
bullet rosettes in cirrus, J. Appl. Meteorol. Clim., 46, 757–775,
https://doi.org/10.1175/JAM2501.1, 2007.
Um, J. and McFarquhar, G. M.: Single-scattering properties of aggregates
plates, Q. J. Roy. Meteor. Soc., 135, 291–304, https://doi.org/10.1002/qj.378, 2009.
Um, J. and McFarquhar, G. M.: Dependence of the single-scattering properties
of small ice crystals on idealized shape models, Atmos. Chem. Phys., 11,
3159–3171, https://doi.org/10.5194/acp-11-3159-2011, 2011.
Um, J. and McFarquhar, G. M.: Optimal numerical methods for determining the
orientation averages of single-scattering properties of atmospheric ice
crystals, J. Quant. Spectrosc. Ra., 127, 207–223,
https://doi.org/10.1016/j.jqsrt.2013.05.020, 2013.
Um, J., McFarquhar, G. M., Hong, Y. P., Lee, S.-S., Jung, C. H., Lawson, R.
P., and Mo, Q.: Dimensions and aspect ratios of natural ice crystals, Atmos.
Chem. Phys., 15, 3933–3956, https://doi.org/10.5194/acp-15-3933-2015, 2015.
Wang, J., Dong, X., and Xi, B.: Investigation of ice cloud microphysical
properties of DCSs using aircraft in situ measurements during MC3E over the
ARM SGP site, J. Geophys. Res., 120, 3533–3552, https://doi.org/10.1002/2014JD022795,
2015.
Yang, P., Gao, B. C., Baum, B. A., Wiscombe, W. J., Hu, Y. X., Nasiri, S. L.,
Soulen, P. F., Heymsfield, A. J., McFarquhar, G. M., and Miloshevich, L. M.:
Sensitivity of cirrus bidirectional reflectance to vertical inhomogeneity of
ice crystal habits and size distributions for two Moderate-Resolution Imaging
Spectroradiometer (MODIS) bands, J. Geophys. Res., 106, 17267–17291, 2001.
Yang, P., Baum, B. A., Heymsfield, A. J., Hu, Y. X., Huang, H.-L., Tsay,
S.-C., and Ackerman, S.: Single-scattering properties of droxtals, J. Quant.
Spectrosc. Ra., 79–80, 1159–1169, 2003.
Yuen, H. K., Princen, J., Illingworth, J., and Kittler, J.: Comparative study
of Hough transform methods for circle finding, Image Vision Comput., 8,
71–77, 1990.
Short summary
During the 2012 Deep Convective Clouds and Chemistry experiment upper anvils of two storms were sampled. The occurrence of well-defined pristine crystals was low in the anvils, while single frozen droplets and frozen droplet aggregates (FDAs) were the dominant habits. A new algorithm was developed to automatically identify the number, size, and relative position of element frozen droplets within FDAs. The morphological characteristics of FDAs were compared with those of black carbon aggregates.
During the 2012 Deep Convective Clouds and Chemistry experiment upper anvils of two storms were...
Altmetrics
Final-revised paper
Preprint