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
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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
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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
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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
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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
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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
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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
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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.
Andrew M. Dzambo, Tristan L'Ecuyer, Kenneth Sinclair, Bastiaan van Diedenhoven, Siddhant Gupta, Greg McFarquhar, Joseph R. O'Brien, Brian Cairns, Andrzej P. Wasilewski, and Mikhail Alexandrov
Atmos. Chem. Phys., 21, 5513–5532, https://doi.org/10.5194/acp-21-5513-2021, https://doi.org/10.5194/acp-21-5513-2021, 2021
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This work highlights a new algorithm using data collected from the 2016–2018 NASA ORACLES field campaign. This algorithm synthesizes cloud and rain measurements to attain estimates of cloud and precipitation properties over the southeast Atlantic Ocean. Estimates produced by this algorithm compare well against in situ estimates. Increased rain fractions and rain rates are found in regions of atmospheric instability. This dataset can be used to explore aerosol–cloud–precipitation interactions.
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
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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
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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.
Ah-Hyun Kim, Seong Soo Yum, Dong Yeong Chang, and Minsu Park
Geosci. Model Dev., 14, 259–273, https://doi.org/10.5194/gmd-14-259-2021, https://doi.org/10.5194/gmd-14-259-2021, 2021
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A new method to estimate the sulfate aerosol hygroscopicity parameter (κSO4) is suggested that can consider κSO4 for two different sulfate species instead of prescribing a single κSO4 value, as in most previous studies. The new method simulates more realistic cloud droplet concentrations and, thus, a more realistic cloud albedo effect than the original method. The new method is simple and readily applicable to modeling studies investigating sulfate aerosols’ effect in aerosol–cloud interactions.
Najin Kim, Seong Soo Yum, Minsu Park, Jong Sung Park, Hye Jung Shin, and Joon Young Ahn
Atmos. Chem. Phys., 20, 11245–11262, https://doi.org/10.5194/acp-20-11245-2020, https://doi.org/10.5194/acp-20-11245-2020, 2020
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Chemical effects on the size-resolved hygroscopicity of urban aerosols were examined based on the KORUS-AQ field campaign data (HTDMA and HR-ToF-AMS). The size-resolved chemical composition data were found to be critical in explaining the size-dependent hygroscopicity, as well as the diurnal variation of κ for small particles. Aerosol mixing state information was associated with the size-resolved chemical composition data to reveal chemical information of different hygroscopicity modes.
Wenchao Han, Zhanqing Li, Fang Wu, Yuwei Zhang, Jianping Guo, Tianning Su, Maureen Cribb, Jiwen Fan, Tianmeng Chen, Jing Wei, and Seoung-Soo Lee
Atmos. Chem. Phys., 20, 6479–6493, https://doi.org/10.5194/acp-20-6479-2020, https://doi.org/10.5194/acp-20-6479-2020, 2020
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Observational data and model simulation were used to analyze the daytime urban heat island intensity (UHII) under polluted and clean conditions in China. We found that aerosols reduce the UHII in summer but increase the UHII in winter. Two mechanisms, the aerosol radiative effect (ARE) and the aerosol dynamic effect (ADE), behave differently in summer and winter. In summer, the UHII is mainly affected by the ARE, and the ADE is weak, and the opposite is the case in winter.
Jiyeon Park, Manuel Dall'Osto, Kihong Park, Yeontae Gim, Hyo Jin Kang, Eunho Jang, Ki-Tae Park, Minsu Park, Seong Soo Yum, Jinyoung Jung, Bang Yong Lee, and Young Jun Yoon
Atmos. Chem. Phys., 20, 5573–5590, https://doi.org/10.5194/acp-20-5573-2020, https://doi.org/10.5194/acp-20-5573-2020, 2020
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The physical properties of aerosol particles throughout the Arctic Ocean and Pacific Ocean were measured aboard the Korean icebreaker R/V Araon during the summer of 2017. A number of new particle formation (NPF) events and growth were frequently observed in both Arctic terrestrial and Arctic marine air masses. This suggests that terrestrial ecosystems – including river outflows and tundra – strongly affect aerosol emissions in the Arctic coastal areas, affecting
radiative forcing.
Seoung Soo Lee, George Kablick III, Zhanqing Li, Chang Hoon Jung, Yong-Sang Choi, Junshik Um, and Won Jun Choi
Atmos. Chem. Phys., 20, 3357–3371, https://doi.org/10.5194/acp-20-3357-2020, https://doi.org/10.5194/acp-20-3357-2020, 2020
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This paper examines a thunderstorm-type cloud that is triggered by wildfire. This paper shows that this cloud has a substantial impact on air components such as water vapor that act as a global warming agent together with carbon dioxide. This paper also shows that that impact is strongly dependent on fire intensity. This raises a possibility that clouds, which are triggered by fire, act as a modulator of climate changes and this function as a modulator is altered by how intense fire is.
Joseph A. Finlon, Greg M. McFarquhar, Stephen W. Nesbitt, Robert M. Rauber, Hugh Morrison, Wei Wu, and Pengfei Zhang
Atmos. Chem. Phys., 19, 3621–3643, https://doi.org/10.5194/acp-19-3621-2019, https://doi.org/10.5194/acp-19-3621-2019, 2019
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A new approach describing the relationship between ice crystal mass (m) and dimension (D) is derived, characterizing it as a set of
equally realizableparameters based on the natural variability in cloud conditions observed by aircraft over the Great Plains. Results from this approach address shortcomings of microphysical parameterization schemes and remote sensing retrievals that employ a single m–D relation for a given ice species or environment.
Emma Järvinen, Olivier Jourdan, David Neubauer, Bin Yao, Chao Liu, Meinrat O. Andreae, Ulrike Lohmann, Manfred Wendisch, Greg M. McFarquhar, Thomas Leisner, and Martin Schnaiter
Atmos. Chem. Phys., 18, 15767–15781, https://doi.org/10.5194/acp-18-15767-2018, https://doi.org/10.5194/acp-18-15767-2018, 2018
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Using light diffraction it is possible to detect microscopic features within ice particles that have not yet been fully characterized. Here, this technique was applied in airborne measurements, where it was found that majority of atmospheric ice particles have features that significantly change the way ice particles interact with solar light. The microscopic features make ice-containing clouds more reflective than previously thought, which could have consequences for predicting our climate.
Seoung Soo Lee, Byung-Gon Kim, Zhanqing Li, Yong-Sang Choi, Chang-Hoon Jung, Junshik Um, Jungbin Mok, and Kyong-Hwan Seo
Atmos. Chem. Phys., 18, 12531–12550, https://doi.org/10.5194/acp-18-12531-2018, https://doi.org/10.5194/acp-18-12531-2018, 2018
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
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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.
Julia Schmale, Silvia Henning, Stefano Decesari, Bas Henzing, Helmi Keskinen, Karine Sellegri, Jurgita Ovadnevaite, Mira L. Pöhlker, Joel Brito, Aikaterini Bougiatioti, Adam Kristensson, Nikos Kalivitis, Iasonas Stavroulas, Samara Carbone, Anne Jefferson, Minsu Park, Patrick Schlag, Yoko Iwamoto, Pasi Aalto, Mikko Äijälä, Nicolas Bukowiecki, Mikael Ehn, Göran Frank, Roman Fröhlich, Arnoud Frumau, Erik Herrmann, Hartmut Herrmann, Rupert Holzinger, Gerard Kos, Markku Kulmala, Nikolaos Mihalopoulos, Athanasios Nenes, Colin O'Dowd, Tuukka Petäjä, David Picard, Christopher Pöhlker, Ulrich Pöschl, Laurent Poulain, André Stephan Henry Prévôt, Erik Swietlicki, Meinrat O. Andreae, Paulo Artaxo, Alfred Wiedensohler, John Ogren, Atsushi Matsuki, Seong Soo Yum, Frank Stratmann, Urs Baltensperger, and Martin Gysel
Atmos. Chem. Phys., 18, 2853–2881, https://doi.org/10.5194/acp-18-2853-2018, https://doi.org/10.5194/acp-18-2853-2018, 2018
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Collocated long-term observations of cloud condensation nuclei (CCN) number concentrations, particle number size distributions and chemical composition from 12 sites are synthesized. Observations cover coastal environments, the Arctic, the Mediterranean, the boreal and rain forest, high alpine and continental background sites, and Monsoon-influenced areas. We interpret regional and seasonal variability. CCN concentrations are predicted with the κ–Köhler model and compared to the measurements.
Seoung Soo Lee, Zhanqing Li, Yuwei Zhang, Hyelim Yoo, Seungbum Kim, Byung-Gon Kim, Yong-Sang Choi, Jungbin Mok, Junshik Um, Kyoung Ock Choi, and Danhong Dong
Atmos. Chem. Phys., 18, 13–29, https://doi.org/10.5194/acp-18-13-2018, https://doi.org/10.5194/acp-18-13-2018, 2018
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This paper compares the contribution of resolutions with that of parameterizations to errors in the simulations of clouds, precipitation, and their interactions with aerosol in numerical weather prediction (NWP) models. This comparison shows that resolutions contribute to errors to a much greater degree than microphysics parameterizations. This finding provides a useful guideline for how to develop NWP models and has not been discussed in previous studies.
Jiyoung Kim, Jhoon Kim, Hi-Ku Cho, Jay Herman, Sang Seo Park, Hyun Kwang Lim, Jae-Hwan Kim, Koji Miyagawa, and Yun Gon Lee
Atmos. Meas. Tech., 10, 3661–3676, https://doi.org/10.5194/amt-10-3661-2017, https://doi.org/10.5194/amt-10-3661-2017, 2017
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Total column ozone (TCO) has been obtained by various ground-based and spaceborne instruments (OMI) with high accuracy. Here, daily TCO measured by a Pandora spectrophotometer (no. 19) installed since the (DRAGON)-NE Asia campaign (2012) was intercompared using Dobson (no. 124), Brewer (no. 148), and OMI measurements from March 2012 to March 2014 at Yonsei University, Seoul, Korea. The results showed that Pandora TCO is in very good agreement with other measurements.
Ann M. Fridlind, Xiaowen Li, Di Wu, Marcus van Lier-Walqui, Andrew S. Ackerman, Wei-Kuo Tao, Greg M. McFarquhar, Wei Wu, Xiquan Dong, Jingyu Wang, Alexander Ryzhkov, Pengfei Zhang, Michael R. Poellot, Andrea Neumann, and Jason M. Tomlinson
Atmos. Chem. Phys., 17, 5947–5972, https://doi.org/10.5194/acp-17-5947-2017, https://doi.org/10.5194/acp-17-5947-2017, 2017
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Understanding observed storm microphysics via computer simulation requires measurements of aerosol on which most hydrometeors form. We prepare aerosol input data for six storms observed over Oklahoma. We demonstrate their use in simulations of a case with widespread ice outflow well sampled by aircraft. Simulations predict too few ice crystals that are too large. We speculate that microphysics found in tropical storms occurred here, likely associated with poorly understood ice multiplication.
Ann M. Fridlind, Rachel Atlas, Bastiaan van Diedenhoven, Junshik Um, Greg M. McFarquhar, Andrew S. Ackerman, Elisabeth J. Moyer, and R. Paul Lawson
Atmos. Chem. Phys., 16, 7251–7283, https://doi.org/10.5194/acp-16-7251-2016, https://doi.org/10.5194/acp-16-7251-2016, 2016
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Images of crystals within mid-latitude cirrus clouds are used to derive consistent ice physical and optical properties for a detailed cloud microphysics model, including size-dependent mass, projected area, and fall speed. Based on habits found, properties are derived for bullet rosettes, their aggregates, and crystals with irregular shapes. Derived bullet rosette fall speeds are substantially greater than reported in past studies, owing to differences in mass, area, or diameter representation.
Jeffrey L. Stith, Brett Basarab, Steven A. Rutledge, and Andrew Weinheimer
Atmos. Chem. Phys., 16, 2243–2254, https://doi.org/10.5194/acp-16-2243-2016, https://doi.org/10.5194/acp-16-2243-2016, 2016
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Lightning-produced NOx and ice particles were studied using airborne measurements in thunderstorm anvil clouds during the Deep Convective Clouds and Chemistry experiment (DC3). These data were compared with radar and Lightning Mapping Array (LMA) measurements. A characteristic signature was found in three anvils that relates the occurrence of frozen cloud droplets and aggregates of frozen droplets to the presence of lightning-produced NOx in these storms.
L. M. Zamora, R. A. Kahn, M. J. Cubison, G. S. Diskin, J. L. Jimenez, Y. Kondo, G. M. McFarquhar, A. Nenes, K. L. Thornhill, A. Wisthaler, A. Zelenyuk, and L. D. Ziemba
Atmos. Chem. Phys., 16, 715–738, https://doi.org/10.5194/acp-16-715-2016, https://doi.org/10.5194/acp-16-715-2016, 2016
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Based on extensive aircraft campaigns, we quantify how biomass burning smoke affects subarctic and Arctic liquid cloud microphysical properties. Enhanced cloud albedo may decrease short-wave radiative flux by between 2 and 4 Wm2 or more in some subarctic conditions. Smoke halved average cloud droplet diameter. In one case study, it also appeared to limit droplet formation. Numerous Arctic background Aitken particles can also interact with combustion particles, perhaps affecting their properties.
J. Um, G. M. McFarquhar, Y. P. Hong, S.-S. Lee, C. H. Jung, R. P. Lawson, and Q. Mo
Atmos. Chem. Phys., 15, 3933–3956, https://doi.org/10.5194/acp-15-3933-2015, https://doi.org/10.5194/acp-15-3933-2015, 2015
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Dimensions of ice crystals increased with an increase in temperature and the L-W relationships of crystals with a given L depended heavily on temperature, whereas the aspect ratio depended only weakly on temperature. The relative frequency of occurrence of plates was much larger in anvil clouds compared to that of columnar crystals (i.e., columns and bullet rosettes), whereas the relative occurrence frequency of columnar crystals was much larger in non-anvil clouds.
J. H. Kim, S. S. Yum, S. Shim, W. J. Kim, M. Park, J.-H. Kim, M.-H. Kim, and S.-C. Yoon
Atmos. Chem. Phys., 14, 8763–8779, https://doi.org/10.5194/acp-14-8763-2014, https://doi.org/10.5194/acp-14-8763-2014, 2014
J. L. Stith, L. M. Avallone, A. Bansemer, B. Basarab, S. W. Dorsi, B. Fuchs, R. P. Lawson, D. C. Rogers, S. Rutledge, and D. W. Toohey
Atmos. Chem. Phys., 14, 1973–1985, https://doi.org/10.5194/acp-14-1973-2014, https://doi.org/10.5194/acp-14-1973-2014, 2014
S.-S. Lee and G. Feingold
Atmos. Chem. Phys., 13, 6713–6726, https://doi.org/10.5194/acp-13-6713-2013, https://doi.org/10.5194/acp-13-6713-2013, 2013
Related subject area
Subject: Clouds and Precipitation | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Measurement report: A survey of meteorological and cloud properties during ACTIVATE’s postfrontal flights and their suitability for Lagrangian case studies
Characterization of fog microphysics and their relationships with visibility at a mountain site in China
Hunting for gravity waves in non-orographic winter storms using 3+ years of regional surface air pressure network and radar observations
Theoretical framework for measuring cloud effective supersaturation fluctuations with an advanced optical system
Investigating the role of typhoon-induced waves and stratospheric hydration in the formation of tropopause cirrus clouds observed during the 2017 Asian monsoon
How does riming influence the observed spatial variability of ice water in mixed-phase clouds?
Moisture Budget Estimates Derived from Airborne Observations in an Arctic Atmospheric River During its Dissipation
In-cloud characteristics observed in US Northeast and Midwest non-orographic winter storms with implications for ice particle mass growth and residence time
Microphysical view of the development and ice production of mid-latitude stratiform clouds with embedded convection during an extratropical cyclone
Clouds and precipitation in the initial phase of marine cold-air outbreaks as observed by airborne remote sensing
Light scattering and microphysical properties of atmospheric bullet rosette ice crystals
Quantified ice-nucleating ability of AgI-containing seeding particles in natural clouds
Estimating the snow density using collocated Parsivel and Micro-Rain Radar measurements: a preliminary study from ICE-POP 2017/2018
Technical note: On the ice microphysics of isolated thunderstorms and non-thunderstorms in southern China – a radar polarimetric perspective
Distinctive aerosol–cloud–precipitation interactions in marine boundary layer clouds from the ACE-ENA and SOCRATES aircraft field campaigns
Aerosol Indirect Effects on Cirrus Clouds Based on Global-Scale Airborne Observations and Machine Learning Models
Drivers of droplet formation in east Mediterranean orographic clouds
Observability of moisture transport divergence in Arctic atmospheric rivers by dropsondes
Elucidating the boundary layer turbulence dissipation rate using high-resolution measurements from a radar wind profiler network over the Tibetan Plateau
Environmental controls on isolated convection during the Amazonian wet season
Isotopic composition of convective rainfall in the inland tropics of Brazil
Measurement report: Cloud and environmental properties associated with aggregated shallow marine cumulus and cumulus congestus
Vertical Profiles of Liquid Water Content in fog layers during the SOFOG3D experiment
Lifecycle of updrafts and mass flux in isolated deep convection over the Amazon rainforest: insights from cell tracking
Thermodynamic and cloud evolution in a cold-air outbreak during HALO-(AC)3: quasi-Lagrangian observations compared to the ERA5 and CARRA reanalyses
Powering aircraft with 100 % sustainable aviation fuel reduces ice crystals in contrails
Supercooled liquid water clouds observed over Dome C, Antarctica: temperature sensitivity and cloud radiative forcing
Role of thermodynamic and turbulence processes on the fog life cycle during SOFOG3D experiment
Characterizing the near-global cloud vertical structures over land using high-resolution radiosonde measurements
Differences in microphysical properties of cirrus at high and mid-latitudes
Sub-cloud rain evaporation in the North Atlantic winter trade winds derived by pairing isotopic data with a bin-resolved microphysical model
Overview and statistical analysis of boundary layer clouds and precipitation over the western North Atlantic Ocean
A set of methods to evaluate the below-cloud evaporation effect on local precipitation isotopic composition: a case study for Xi'an, China
Earth-system-model evaluation of cloud and precipitation occurrence for supercooled and warm clouds over the Southern Ocean's Macquarie Island
Pollution slightly enhances atmospheric cooling by low-level clouds in tropical West Africa
Investigating an indirect aviation effect on mid-latitude cirrus clouds – linking lidar-derived optical properties to in situ measurements
Investigating the vertical extent and short-wave radiative effects of the ice phase in Arctic summertime low-level clouds
Microphysical and thermodynamic phase analyses of Arctic low-level clouds measured above the sea ice and the open ocean in spring and summer
Aircraft observations of gravity wave activity and turbulence in the tropical tropopause layer: prevalence, influence on cirrus clouds, and comparison with global storm-resolving models
Influence of air mass origin on microphysical properties of low-level clouds in a subarctic environment
Sensitivity of convectively driven tropical tropopause cirrus properties to ice habits in high-resolution simulations
Upper-tropospheric slightly ice-subsaturated regions: frequency of occurrence and statistical evidence for the appearance of contrail cirrus
Examination of aerosol indirect effects during cirrus cloud evolution
In situ microphysics observations of intense pyroconvection from a large wildfire
Conditions favorable for secondary ice production in Arctic mixed-phase clouds
Interaction between cloud–radiation, atmospheric dynamics and thermodynamics based on observational data from GoAmazon 2014/15 and a cloud-resolving model
Snowfall in Northern Finland derives mostly from ice clouds
Observation of secondary ice production in clouds at low temperatures
In situ and satellite-based estimates of cloud properties and aerosol–cloud interactions over the southeast Atlantic Ocean
Ice fog observed at cirrus temperatures at Dome C, Antarctic Plateau
Florian Tornow, Ann Fridlind, George Tselioudis, Brian Cairns, Andrew Ackerman, Seethala Chellappan, David Painemal, Paquita Zuidema, Christiane Voigt, Simon Kirschler, and Armin Sorooshian
Atmos. Chem. Phys., 25, 5053–5074, https://doi.org/10.5194/acp-25-5053-2025, https://doi.org/10.5194/acp-25-5053-2025, 2025
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The recent NASA campaign ACTIVATE (Aerosol Cloud meTeorology Interactions oVer the western ATlantic Experiment) performed 71 tandem flights in mid-latitude marine cold-air outbreaks off the US eastern seaboard. We provide meteorological and cloud transition stage context, allowing us to identify days that are most suitable for Lagrangian modeling and analysis. Surveyed cloud properties show signatures of cloud microphysical processes, such as cloud-top entrainment and secondary ice formation.
Quan Liu, Xiaojing Shen, Junying Sun, Yangmei Zhang, Bing Qi, Qianli Ma, Lujie Han, Honghui Xu, Xinyao Hu, Jiayuan Lu, Shuo Liu, Aoyuan Yu, Linlin Liang, Qian Gao, Hong Wang, Huizheng Che, and Xiaoye Zhang
Atmos. Chem. Phys., 25, 3253–3267, https://doi.org/10.5194/acp-25-3253-2025, https://doi.org/10.5194/acp-25-3253-2025, 2025
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Through simultaneous measurements of aerosol particles and fog droplets, the evolution of droplets size distribution during the eight observed fog events was investigated. The results showed that the concentration and size distribution of pre-fog aerosol had significant impacts on fog microphysical characteristics. The extinction of fog interstitial particles played an important role in visibility degradation for light fogs, especially in polluted regions.
Luke R. Allen, Sandra E. Yuter, Matthew A. Miller, and Laura M. Tomkins
Atmos. Chem. Phys., 25, 1765–1790, https://doi.org/10.5194/acp-25-1765-2025, https://doi.org/10.5194/acp-25-1765-2025, 2025
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Atmospheric gravity waves (GWs) are air oscillations in which buoyancy is the restoring force, and they may enhance precipitation under certain conditions. We used 3+ seasons of pressure data to identify GWs with wavelengths ≤ 170 km in the Toronto and New York metropolitan areas in the context of snow storms. We found only six GW events during snow storms, suggesting that GWs on those scales are uncommon at the two locations during snow storms and, thus, do not often enhance snowfall.
Ye Kuang, Jiangchuan Tao, Hanbing Xu, Li Liu, Pengfei Liu, Wanyun Xu, Weiqi Xu, Yele Sun, and Chunsheng Zhao
Atmos. Chem. Phys., 25, 1163–1174, https://doi.org/10.5194/acp-25-1163-2025, https://doi.org/10.5194/acp-25-1163-2025, 2025
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This study presents a novel optical framework to measure supersaturation, a fundamental parameter in cloud physics, by observing the scattering properties of particles that have or have not grown into cloud droplets. The technique offers high-resolution measurements, capturing essential fluctuations in supersaturation necessary for understanding cloud physics.
Amit Kumar Pandit, Jean-Paul Vernier, Thomas Duncan Fairlie, Kristopher M. Bedka, Melody A. Avery, Harish Gadhavi, Madineni Venkat Ratnam, Sanjeev Dwivedi, Kasimahanthi Amar Jyothi, Frank G. Wienhold, Holger Vömel, Hongyu Liu, Bo Zhang, Buduru Suneel Kumar, Tra Dinh, and Achuthan Jayaraman
Atmos. Chem. Phys., 24, 14209–14238, https://doi.org/10.5194/acp-24-14209-2024, https://doi.org/10.5194/acp-24-14209-2024, 2024
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This study investigates the formation mechanism of a tropopause cirrus cloud layer observed at extremely cold temperatures over Hyderabad in India during the 2017 Asian summer monsoon using balloon-borne sensors. Ice crystals smaller than 50 µm were found in this optically thin cirrus cloud layer. Combined analysis of back trajectories, satellite, and model data revealed that the formation of this layer was influenced by waves and stratospheric hydration induced by typhoon Hato.
Nina Maherndl, Manuel Moser, Imke Schirmacher, Aaron Bansemer, Johannes Lucke, Christiane Voigt, and Maximilian Maahn
Atmos. Chem. Phys., 24, 13935–13960, https://doi.org/10.5194/acp-24-13935-2024, https://doi.org/10.5194/acp-24-13935-2024, 2024
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It is not clear why ice crystals in clouds occur in clusters. Here, airborne measurements of clouds in mid-latitudes and high latitudes are used to study the spatial variability of ice. Further, we investigate the influence of riming, which occurs when liquid droplets freeze onto ice crystals. We find that riming enhances the occurrence of ice clusters. In the Arctic, riming leads to ice clustering at spatial scales of 3–5 km. This is due to updrafts and not higher amounts of liquid water.
Henning Dorff, Florian Ewald, Heike Konow, Mario Mech, Davide Ori, Vera Schemann, Andreas Walbröl, Manfred Wendisch, and Felix Ament
EGUsphere, https://doi.org/10.5194/egusphere-2024-3632, https://doi.org/10.5194/egusphere-2024-3632, 2024
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Using observations of an Arctic Atmospheric River (AR) from a long-range research aircraft, we analyse how moisture transported into the Arctic by the AR is transformed and how it interacts with the Arctic environment. The moisture transport divergence is the main driver of local moisture change over time. Surface precipitation and evaporation are rather weak when averaged over extended AR sectors, although considerable heterogeneity of precipitation within the AR is observed.
Luke R. Allen, Sandra E. Yuter, Declan M. Crowe, Matthew A. Miller, and K. Lee Thornhill
EGUsphere, https://doi.org/10.5194/egusphere-2024-3808, https://doi.org/10.5194/egusphere-2024-3808, 2024
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We analyzed in-cloud characteristics using in situ measurements from 42 research flights across two field campaigns into non-orographic, non-lake effect winter storms. Much of the storm volume contains weak vertical motions (a few cm s-1), and most updrafts ≥ 0.5 m s-1 are small (< 1 km). Within 2 km of cloud radar echo top, stronger vertical motions and conditions for ice particle growth are more common. This implies the importance of cloud-top generating cells for production of snow particles.
Yuanmou Du, Dantong Liu, Delong Zhao, Mengyu Huang, Ping Tian, Dian Wen, Wei Xiao, Wei Zhou, Hui He, Baiwan Pan, Dongfei Zuo, Xiange Liu, Yingying Jing, Rong Zhang, Jiujiang Sheng, Fei Wang, Yu Huang, Yunbo Chen, and Deping Ding
Atmos. Chem. Phys., 24, 13429–13444, https://doi.org/10.5194/acp-24-13429-2024, https://doi.org/10.5194/acp-24-13429-2024, 2024
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By conducting in situ measurements, we investigated ice production processes in stratiform clouds with embedded convection over the North China Plain. The results show that the ice number concentration is strongly related to the distance to the cloud top, and the level with a larger distance to the cloud top has more graupel falling from upper levels, which promotes collision and coalescence between graupel and droplets and enhances secondary ice production.
Imke Schirmacher, Sabrina Schnitt, Marcus Klingebiel, Nina Maherndl, Benjamin Kirbus, André Ehrlich, Mario Mech, and Susanne Crewell
Atmos. Chem. Phys., 24, 12823–12842, https://doi.org/10.5194/acp-24-12823-2024, https://doi.org/10.5194/acp-24-12823-2024, 2024
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During Arctic marine cold-air outbreaks, cold air flows from sea ice over open water. Roll circulations evolve, forming cloud streets. We investigate the initial circulation and cloud development using high-resolution airborne measurements. We compute the distance an air mass traveled over water (fetch) from back trajectories. Cloud streets form at 15 km fetch, cloud cover strongly increases at around 20 km, and precipitation forms at around 30 km.
Shawn Wendell Wagner, Martin Schnaiter, Guanglang Xu, Franziska Nehlert, and Emma Järvinen
EGUsphere, https://doi.org/10.5194/egusphere-2024-3316, https://doi.org/10.5194/egusphere-2024-3316, 2024
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Understanding the interaction between cirrus clouds and solar radiation is critical for modeling the Earth’s climate. A common crystal type found in cirrus clouds is the bullet rosette. Here, atmospheric bullet rosettes measured from jet aircraft are analyzed for their morphological and radiative properties. Atmospheric bullet rosettes are found to be more morphologically complex than previously assumed. This complexity has a significant impact on their radiative properties.
Anna J. Miller, Christopher Fuchs, Fabiola Ramelli, Huiying Zhang, Nadja Omanovic, Robert Spirig, Claudia Marcolli, Zamin A. Kanji, Ulrike Lohmann, and Jan Henneberger
EGUsphere, https://doi.org/10.5194/egusphere-2024-3230, https://doi.org/10.5194/egusphere-2024-3230, 2024
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We analyzed the ability of silver iodide particles to form ice crystals in naturally-occurring liquid clouds below 0 °C and found that ≈0.1−1 % of particles nucleate ice, with a negative dependence on temperature. Contextualizing our results with previous laboratory studies, we help to bridge the gap between laboratory and field experiments and which also helps to inform future cloud seeding projects.
Wei-Yu Chang, Yung-Chuan Yang, Chen-Yu Hung, Kwonil Kim, Gyuwon Lee, and Ali Tokay
Atmos. Chem. Phys., 24, 11955–11979, https://doi.org/10.5194/acp-24-11955-2024, https://doi.org/10.5194/acp-24-11955-2024, 2024
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Snow density is derived by collocated Micro-Rain Radar (MRR) and Parsivel (ICE-POP 2017/2018). We apply the particle size distribution from Parsivel to a T-matrix backscattering simulation and compare with ZHH from MRR. Bulk density and bulk water fractions are derived from comparing simulated and calculated ZHH. Retrieved bulk density is validated by comparing snowfall rate measurements from Pluvio and the Precipitation Imaging Package. Snowfall rate consistency confirms the algorithm.
Chuanhong Zhao, Yijun Zhang, Dong Zheng, Haoran Li, Sai Du, Xueyan Peng, Xiantong Liu, Pengguo Zhao, Jiafeng Zheng, and Juan Shi
Atmos. Chem. Phys., 24, 11637–11651, https://doi.org/10.5194/acp-24-11637-2024, https://doi.org/10.5194/acp-24-11637-2024, 2024
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Understanding lightning activity is important for meteorology and atmospheric chemistry. However, the occurrence of lightning activity in clouds is uncertain. In this study, we quantified the difference between isolated thunderstorms and non-thunderstorms. We showed that lightning activity was more likely to occur with more graupel volume and/or riming. A deeper ZDR column was associated with lightning occurrence. This information can aid in a deeper understanding of lighting physics.
Xiaojian Zheng, Xiquan Dong, Baike Xi, Timothy Logan, and Yuan Wang
Atmos. Chem. Phys., 24, 10323–10347, https://doi.org/10.5194/acp-24-10323-2024, https://doi.org/10.5194/acp-24-10323-2024, 2024
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The marine boundary layer aerosol–cloud interactions (ACIs) are examined using in situ measurements from two aircraft campaigns over the eastern North Atlantic (ACE-ENA) and Southern Ocean (SOCRATES). The SOCRATES clouds have more and smaller cloud droplets. The ACE-ENA clouds exhibit stronger drizzle formation and growth. Results found distinctive aerosol–cloud interactions for two campaigns. The drizzle processes significantly alter sub-cloud aerosol budgets and impact the ACI assessments.
Derek Ngo, Minghui Diao, Ryan J. Patnaude, Sarah Woods, and Glenn Diskin
EGUsphere, https://doi.org/10.5194/egusphere-2024-2122, https://doi.org/10.5194/egusphere-2024-2122, 2024
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Key controlling factors of cirrus clouds were individually quantified using machine learning models, based on global-scale in-situ observations compiled from 12 flight campaigns at 67° S – 87° N. Relative humidity shows much larger effects on cirrus occurrences than vertical velocity. Aerosol indirect effects are seen from both large and small aerosols, which affect predictions of cirrus occurrences. Large aerosols significantly improve predictions of ice water content but not small aerosols.
Romanos Foskinis, Ghislain Motos, Maria I. Gini, Olga Zografou, Kunfeng Gao, Stergios Vratolis, Konstantinos Granakis, Ville Vakkari, Kalliopi Violaki, Andreas Aktypis, Christos Kaltsonoudis, Zongbo Shi, Mika Komppula, Spyros N. Pandis, Konstantinos Eleftheriadis, Alexandros Papayannis, and Athanasios Nenes
Atmos. Chem. Phys., 24, 9827–9842, https://doi.org/10.5194/acp-24-9827-2024, https://doi.org/10.5194/acp-24-9827-2024, 2024
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Analysis of modeling, in situ, and remote sensing measurements reveals the microphysical state of orographic clouds and their response to aerosol from the boundary layer and free troposphere. We show that cloud response to aerosol is robust, as predicted supersaturation and cloud droplet number levels agree with those determined from in-cloud measurements. The ability to determine if clouds are velocity- or aerosol-limited allows for novel model constraints and remote sensing products.
Henning Dorff, Heike Konow, Vera Schemann, and Felix Ament
Atmos. Chem. Phys., 24, 8771–8795, https://doi.org/10.5194/acp-24-8771-2024, https://doi.org/10.5194/acp-24-8771-2024, 2024
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Using synthetic dropsondes, we assess how discrete spatial sampling and temporal evolution during flight affect the accuracy of real sonde-based moisture transport divergence in Arctic atmospheric rivers (ARs). Non-instantaneous sampling during temporal AR evolution deteriorates the divergence values more than spatial undersampling. Moisture advection is the dominating factor but most sensitive to the sampling method. We suggest a minimum of seven sondes to resolve the AR divergence components.
Deli Meng, Jianping Guo, Xiaoran Guo, Yinjun Wang, Ning Li, Yuping Sun, Zhen Zhang, Na Tang, Haoran Li, Fan Zhang, Bing Tong, Hui Xu, and Tianmeng Chen
Atmos. Chem. Phys., 24, 8703–8720, https://doi.org/10.5194/acp-24-8703-2024, https://doi.org/10.5194/acp-24-8703-2024, 2024
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The turbulence in the planetary boundary layer (PBL) over the Tibetan Plateau (TP) remains unclear. Here we elucidate the vertical profile of and temporal variation in the turbulence dissipation rate in the PBL over the TP based on a radar wind profiler (RWP) network. To the best of our knowledge, this is the first time that the turbulence profile over the whole TP has been revealed. Furthermore, the possible mechanisms of clouds acting on the PBL turbulence structure are investigated.
Leandro Alex Moreira Viscardi, Giuseppe Torri, David K. Adams, and Henrique de Melo Jorge Barbosa
Atmos. Chem. Phys., 24, 8529–8548, https://doi.org/10.5194/acp-24-8529-2024, https://doi.org/10.5194/acp-24-8529-2024, 2024
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We evaluate the environmental conditions that control how clouds grow from fair weather cumulus into severe thunderstorms during the Amazonian wet season. Days with rain clouds begin with more moisture in the air and have strong convergence in the afternoon, while precipitation intensity increases with large-scale vertical velocity, moisture, and low-level wind. These results contribute to understanding how clouds form over the rainforest.
Vinicius dos Santos, Didier Gastmans, Ana María Durán-Quesada, Ricardo Sánchez-Murillo, Kazimierz Rozanski, Oliver Kracht, and Demilson de Assis Quintão
Atmos. Chem. Phys., 24, 6663–6680, https://doi.org/10.5194/acp-24-6663-2024, https://doi.org/10.5194/acp-24-6663-2024, 2024
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We present novel findings on convective rainfall, summer rain in the late afternoon, by coupling water stable isotopes, micro rain radar, and satellite data. We found the tallest clouds in the afternoon and much smaller clouds at night, resulting in differences in day–night ratios in water stable isotopes. We sampled rain and meteorological variables every 5–10 min, allowing us to evaluate the development of convective rainfall, contributing to knowledge of rainfall related to extreme events.
Ewan Crosbie, Luke D. Ziemba, Michael A. Shook, Taylor Shingler, Johnathan W. Hair, Armin Sorooshian, Richard A. Ferrare, Brian Cairns, Yonghoon Choi, Joshua DiGangi, Glenn S. Diskin, Chris Hostetler, Simon Kirschler, Richard H. Moore, David Painemal, Claire Robinson, Shane T. Seaman, K. Lee Thornhill, Christiane Voigt, and Edward Winstead
Atmos. Chem. Phys., 24, 6123–6152, https://doi.org/10.5194/acp-24-6123-2024, https://doi.org/10.5194/acp-24-6123-2024, 2024
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Marine clouds are found to clump together in regions or lines, readily discernible from satellite images of the ocean. While clustering is also a feature of deep storm clouds, we focus on smaller cloud systems associated with fair weather and brief localized showers. Two aircraft sampled the region around these shallow systems: one incorporated measurements taken within, adjacent to, and below the clouds, while the other provided a survey from above using remote sensing techniques.
Théophane Costabloz, Frédéric Burnet, Christine Lac, Pauline Martinet, Julien Delanoë, Susana Jorquera, and Maroua Fathalli
EGUsphere, https://doi.org/10.5194/egusphere-2024-1344, https://doi.org/10.5194/egusphere-2024-1344, 2024
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This study documents vertical profiles of liquid water content (LWC) in fogs from in situ measurements collected during the SOFOG3D field campaign in 2019–2020. The analysis of 140 vertical profiles reveals a reverse trend in LWC, maximum values at ground decreasing with height, during stable conditions in optically thin fogs, evolving towards quasi-adiabatic characteristics when fogs become thick. These results offer new perspectives for better constraining fog numerical simulations.
Siddhant Gupta, Dié Wang, Scott E. Giangrande, Thiago S. Biscaro, and Michael P. Jensen
Atmos. Chem. Phys., 24, 4487–4510, https://doi.org/10.5194/acp-24-4487-2024, https://doi.org/10.5194/acp-24-4487-2024, 2024
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We examine the lifecycle of isolated deep convective clouds (DCCs) in the Amazon rainforest. Weather radar echoes from the DCCs are tracked to evaluate their lifecycle. The DCC size and intensity increase, reach a peak, and then decrease over the DCC lifetime. Vertical profiles of air motion and mass transport from different seasons are examined to understand the transport of energy and momentum within DCC cores and to address the deficiencies in simulating DCCs using weather and climate models.
Benjamin Kirbus, Imke Schirmacher, Marcus Klingebiel, Michael Schäfer, André Ehrlich, Nils Slättberg, Johannes Lucke, Manuel Moser, Hanno Müller, and Manfred Wendisch
Atmos. Chem. Phys., 24, 3883–3904, https://doi.org/10.5194/acp-24-3883-2024, https://doi.org/10.5194/acp-24-3883-2024, 2024
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A research aircraft is used to track the changes in air temperature, moisture, and cloud properties for air that moves from cold Arctic sea ice onto warmer oceanic waters. The measurements are compared to two reanalysis models named ERA5 and CARRA. The biggest differences are found for air temperature over the sea ice and moisture over the ocean. CARRA data are more accurate than ERA5 because they better simulate the sea ice, the transition from sea ice to open ocean, and the forming clouds.
Raphael Satoru Märkl, Christiane Voigt, Daniel Sauer, Rebecca Katharina Dischl, Stefan Kaufmann, Theresa Harlaß, Valerian Hahn, Anke Roiger, Cornelius Weiß-Rehm, Ulrike Burkhardt, Ulrich Schumann, Andreas Marsing, Monika Scheibe, Andreas Dörnbrack, Charles Renard, Maxime Gauthier, Peter Swann, Paul Madden, Darren Luff, Reetu Sallinen, Tobias Schripp, and Patrick Le Clercq
Atmos. Chem. Phys., 24, 3813–3837, https://doi.org/10.5194/acp-24-3813-2024, https://doi.org/10.5194/acp-24-3813-2024, 2024
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In situ measurements of contrails from a large passenger aircraft burning 100 % sustainable aviation fuel (SAF) show a 56 % reduction in contrail ice crystal numbers compared to conventional Jet A-1. Results from a climate model initialized with the observations suggest a significant decrease in radiative forcing from contrails. Our study confirms that future increased use of low aromatic SAF can reduce the climate impact from aviation.
Philippe Ricaud, Massimo Del Guasta, Angelo Lupi, Romain Roehrig, Eric Bazile, Pierre Durand, Jean-Luc Attié, Alessia Nicosia, and Paolo Grigioni
Atmos. Chem. Phys., 24, 613–630, https://doi.org/10.5194/acp-24-613-2024, https://doi.org/10.5194/acp-24-613-2024, 2024
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Clouds affect the Earth's climate in ways that depend on the type of cloud (solid/liquid water). From observations at Concordia (Antarctica), we show that in supercooled liquid water (liquid water for temperatures below 0°C) clouds (SLWCs), temperature and SLWC radiative forcing increase with liquid water (up to 70 W m−2). We extrapolated that the maximum SLWC radiative forcing can reach 40 W m−2 over the Antarctic Peninsula, highlighting the importance of SLWCs for global climate prediction.
Cheikh Dione, Martial Haeffelin, Frédéric Burnet, Christine Lac, Guylaine Canut, Julien Delanoë, Jean-Charles Dupont, Susana Jorquera, Pauline Martinet, Jean-François Ribaud, and Felipe Toledo
Atmos. Chem. Phys., 23, 15711–15731, https://doi.org/10.5194/acp-23-15711-2023, https://doi.org/10.5194/acp-23-15711-2023, 2023
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This paper documents the role of thermodynamics and turbulence in the fog life cycle over southwestern France. It is based on a unique dataset collected during the SOFOG3D field campaign in autumn and winter 2019–2020. The paper gives a threshold for turbulence driving the different phases of the fog life cycle and the role of advection in the night-time dissipation of fog. The results can be operationalised to nowcast fog and improve short-range forecasts in numerical weather prediction models.
Hui Xu, Jianping Guo, Bing Tong, Jinqiang Zhang, Tianmeng Chen, Xiaoran Guo, Jian Zhang, and Wenqing Chen
Atmos. Chem. Phys., 23, 15011–15038, https://doi.org/10.5194/acp-23-15011-2023, https://doi.org/10.5194/acp-23-15011-2023, 2023
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The radiative effect of cloud remains one of the largest uncertain factors in climate change, largely due to the lack of cloud vertical structure (CVS) observations. The study presents the first near-global CVS climatology using high-vertical-resolution soundings. Single-layer cloud mainly occurs over arid regions. As the number of cloud layers increases, clouds tend to have lower bases and thinner layer thicknesses. The occurrence frequency of cloud exhibits a pronounced seasonal diurnal cycle.
Elena De La Torre Castro, Tina Jurkat-Witschas, Armin Afchine, Volker Grewe, Valerian Hahn, Simon Kirschler, Martina Krämer, Johannes Lucke, Nicole Spelten, Heini Wernli, Martin Zöger, and Christiane Voigt
Atmos. Chem. Phys., 23, 13167–13189, https://doi.org/10.5194/acp-23-13167-2023, https://doi.org/10.5194/acp-23-13167-2023, 2023
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In this study, we show the differences in the microphysical properties between high-latitude (HL) cirrus and mid-latitude (ML) cirrus over the Arctic, North Atlantic, and central Europe during summer. The in situ measurements are combined with backward trajectories to investigate the influence of the region on cloud formation. We show that HL cirrus are characterized by a lower concentration of larger ice crystals when compared to ML cirrus.
Mampi Sarkar, Adriana Bailey, Peter Blossey, Simon P. de Szoeke, David Noone, Estefanía Quiñones Meléndez, Mason D. Leandro, and Patrick Y. Chuang
Atmos. Chem. Phys., 23, 12671–12690, https://doi.org/10.5194/acp-23-12671-2023, https://doi.org/10.5194/acp-23-12671-2023, 2023
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We study rain evaporation characteristics below shallow cumulus clouds over the North Atlantic Ocean by pairing isotope observations with a microphysical model. The modeled fraction of rain mass that evaporates below the cloud strongly depends on the raindrop size and distribution width. Moreover, the higher the rain mass fraction evaporated, the greater the change in deuterium excess. In this way, rain evaporation could be studied independently using only isotope and microphysical observations.
Simon Kirschler, Christiane Voigt, Bruce E. Anderson, Gao Chen, Ewan C. Crosbie, Richard A. Ferrare, Valerian Hahn, Johnathan W. Hair, Stefan Kaufmann, Richard H. Moore, David Painemal, Claire E. Robinson, Kevin J. Sanchez, Amy J. Scarino, Taylor J. Shingler, Michael A. Shook, Kenneth L. Thornhill, Edward L. Winstead, Luke D. Ziemba, and Armin Sorooshian
Atmos. Chem. Phys., 23, 10731–10750, https://doi.org/10.5194/acp-23-10731-2023, https://doi.org/10.5194/acp-23-10731-2023, 2023
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In this study we present an overview of liquid and mixed-phase clouds and precipitation in the marine boundary layer over the western North Atlantic Ocean. We compare microphysical properties of pure liquid clouds to mixed-phase clouds and show that the initiation of the ice phase in mixed-phase clouds promotes precipitation. The observational data presented in this study are well suited for investigating the processes that give rise to liquid and mixed-phase clouds, ice, and precipitation.
Meng Xing, Weiguo Liu, Jing Hu, and Zheng Wang
Atmos. Chem. Phys., 23, 9123–9136, https://doi.org/10.5194/acp-23-9123-2023, https://doi.org/10.5194/acp-23-9123-2023, 2023
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The below-cloud evaporation effect (BCE) on precipitation largely impacts the final isotopic composition. However, determining the BCE effect remains poorly constrained. Our work used a ΔdΔδ diagram to differentiate the below-cloud processes. Moreover, by comparing two different computing methods, we considered that both methods are suitable for evaluation the BCE, except for snowfall events. Overall, our work compiled a set of effective methods to evaluate the BCE effect.
McKenna W. Stanford, Ann M. Fridlind, Israel Silber, Andrew S. Ackerman, Greg Cesana, Johannes Mülmenstädt, Alain Protat, Simon Alexander, and Adrian McDonald
Atmos. Chem. Phys., 23, 9037–9069, https://doi.org/10.5194/acp-23-9037-2023, https://doi.org/10.5194/acp-23-9037-2023, 2023
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Clouds play an important role in the Earth’s climate system as they modulate the amount of radiation that either reaches the surface or is reflected back to space. This study demonstrates an approach to robustly evaluate surface-based observations against a large-scale model. We find that the large-scale model precipitates too infrequently relative to observations, contrary to literature documentation suggesting otherwise based on satellite measurements.
Valerian Hahn, Ralf Meerkötter, Christiane Voigt, Sonja Gisinger, Daniel Sauer, Valéry Catoire, Volker Dreiling, Hugh Coe, Cyrille Flamant, Stefan Kaufmann, Jonas Kleine, Peter Knippertz, Manuel Moser, Philip Rosenberg, Hans Schlager, Alfons Schwarzenboeck, and Jonathan Taylor
Atmos. Chem. Phys., 23, 8515–8530, https://doi.org/10.5194/acp-23-8515-2023, https://doi.org/10.5194/acp-23-8515-2023, 2023
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During the DACCIWA campaign in West Africa, we found a 35 % increase in the cloud droplet concentration that formed in a polluted compared with a less polluted environment and a decrease of 17 % in effective droplet diameter. Radiative transfer simulations, based on the measured cloud properties, reveal that these low-level polluted clouds radiate only 2.6 % more energy back to space, compared with a less polluted cloud. The corresponding additional decrease in temperature is rather small.
Silke Groß, Tina Jurkat-Witschas, Qiang Li, Martin Wirth, Benedikt Urbanek, Martina Krämer, Ralf Weigel, and Christiane Voigt
Atmos. Chem. Phys., 23, 8369–8381, https://doi.org/10.5194/acp-23-8369-2023, https://doi.org/10.5194/acp-23-8369-2023, 2023
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Aviation-emitted aerosol can have an impact on cirrus clouds. We present optical and microphysical properties of mid-latitude cirrus clouds which were formed under the influence of aviation-emitted aerosol or which were formed under rather pristine conditions. We find that cirrus clouds affected by aviation-emitted aerosol show larger values of the particle linear depolarization ratio, larger mean effective ice particle diameters and decreased ice particle number concentrations.
Emma Järvinen, Franziska Nehlert, Guanglang Xu, Fritz Waitz, Guillaume Mioche, Regis Dupuy, Olivier Jourdan, and Martin Schnaiter
Atmos. Chem. Phys., 23, 7611–7633, https://doi.org/10.5194/acp-23-7611-2023, https://doi.org/10.5194/acp-23-7611-2023, 2023
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The Arctic is warming faster than other regions. Arctic low-level mixed-phase clouds, where ice crystals and liquid droplets co-exist, are thought to have an important role in Arctic warming. Here we show airborne measurements of vertical distribution of liquid and ice particles and their relative abundance. Ice particles are found in relative warm clouds, which can be explained by multiplication of existing ice crystals. However, the role of ice particles in redistributing sun light is minimal.
Manuel Moser, Christiane Voigt, Tina Jurkat-Witschas, Valerian Hahn, Guillaume Mioche, Olivier Jourdan, Régis Dupuy, Christophe Gourbeyre, Alfons Schwarzenboeck, Johannes Lucke, Yvonne Boose, Mario Mech, Stephan Borrmann, André Ehrlich, Andreas Herber, Christof Lüpkes, and Manfred Wendisch
Atmos. Chem. Phys., 23, 7257–7280, https://doi.org/10.5194/acp-23-7257-2023, https://doi.org/10.5194/acp-23-7257-2023, 2023
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This study provides a comprehensive microphysical and thermodynamic phase analysis of low-level clouds in the northern Fram Strait, above the sea ice and the open ocean, during spring and summer. Using airborne in situ cloud data, we show that the properties of Arctic low-level clouds vary significantly with seasonal meteorological situations and surface conditions. The observations presented in this study can help one to assess the role of clouds in the Arctic climate system.
Rachel Atlas and Christopher S. Bretherton
Atmos. Chem. Phys., 23, 4009–4030, https://doi.org/10.5194/acp-23-4009-2023, https://doi.org/10.5194/acp-23-4009-2023, 2023
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The tropical tropopause layer exists between the troposphere and the stratosphere in the tropics. Very thin cirrus clouds cool Earth's surface by scrubbing water vapor (a greenhouse gas) out of air parcels as they ascend through the tropical tropopause layer on their way to the stratosphere. We show observational evidence from aircraft that small-scale (< 100 km) gravity waves and turbulence increase the amount of ice in these clouds and may allow them to remove more water vapor from the air.
Konstantinos Matthaios Doulgeris, Ville Vakkari, Ewan J. O'Connor, Veli-Matti Kerminen, Heikki Lihavainen, and David Brus
Atmos. Chem. Phys., 23, 2483–2498, https://doi.org/10.5194/acp-23-2483-2023, https://doi.org/10.5194/acp-23-2483-2023, 2023
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We investigated how different long-range-transported air masses can affect the microphysical properties of low-level clouds in a clean subarctic environment. A connection was revealed. Higher values of cloud droplet number concentrations were related to continental air masses, whereas the lowest values of number concentrations were related to marine air masses. These were characterized by larger cloud droplets. Clouds in all regions were sensitive to increases in cloud number concentration.
Fayçal Lamraoui, Martina Krämer, Armin Afchine, Adam B. Sokol, Sergey Khaykin, Apoorva Pandey, and Zhiming Kuang
Atmos. Chem. Phys., 23, 2393–2419, https://doi.org/10.5194/acp-23-2393-2023, https://doi.org/10.5194/acp-23-2393-2023, 2023
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Cirrus in the tropical tropopause layer (TTL) can play a key role in vertical transport. We investigate the role of different cloud regimes and the associated ice habits in regulating the properties of the TTL. We use high-resolution numerical experiments at the scales of large-eddy simulations (LESs) and aircraft measurements. We found that LES-scale parameterizations that predict ice shape are crucial for an accurate representation of TTL cirrus and thus the associated (de)hydration process.
Yun Li, Christoph Mahnke, Susanne Rohs, Ulrich Bundke, Nicole Spelten, Georgios Dekoutsidis, Silke Groß, Christiane Voigt, Ulrich Schumann, Andreas Petzold, and Martina Krämer
Atmos. Chem. Phys., 23, 2251–2271, https://doi.org/10.5194/acp-23-2251-2023, https://doi.org/10.5194/acp-23-2251-2023, 2023
Short summary
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The radiative effect of aviation-induced cirrus is closely related to ambient conditions and its microphysical properties. Our study investigated the occurrence of contrail and natural cirrus measured above central Europe in spring 2014. It finds that contrail cirrus appears frequently in the pressure range 200 to 245 hPa and occurs more often in slightly ice-subsaturated environments than expected. Avoiding slightly ice-subsaturated regions by aviation might help mitigate contrail cirrus.
Flor Vanessa Maciel, Minghui Diao, and Ryan Patnaude
Atmos. Chem. Phys., 23, 1103–1129, https://doi.org/10.5194/acp-23-1103-2023, https://doi.org/10.5194/acp-23-1103-2023, 2023
Short summary
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Aerosol indirect effects on cirrus clouds are investigated during cirrus evolution, using global-scale in situ observations and climate model simulations. As cirrus evolves, the mechanisms to form ice crystals also change with time. Both small and large aerosols are found to affect cirrus properties. Southern Hemisphere cirrus appears to be more sensitive to additional aerosols. The climate model underestimates ice crystal mass, likely due to biases of relative humidity and vertical velocity.
David E. Kingsmill, Jeffrey R. French, and Neil P. Lareau
Atmos. Chem. Phys., 23, 1–21, https://doi.org/10.5194/acp-23-1-2023, https://doi.org/10.5194/acp-23-1-2023, 2023
Short summary
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This study uses in situ aircraft measurements to characterize the size and shape distributions of 10 µm to 6 mm diameter particles observed during six penetrations of wildfire-induced pyroconvection. Particles sampled in one penetration of a smoke plume are most likely pyrometeors composed of ash. The other penetrations are through pyrocumulus clouds where particle composition is most likely a combination of hydrometeors (ice particles) and pyrometeors (ash).
Julie Thérèse Pasquier, Jan Henneberger, Fabiola Ramelli, Annika Lauber, Robert Oscar David, Jörg Wieder, Tim Carlsen, Rosa Gierens, Marion Maturilli, and Ulrike Lohmann
Atmos. Chem. Phys., 22, 15579–15601, https://doi.org/10.5194/acp-22-15579-2022, https://doi.org/10.5194/acp-22-15579-2022, 2022
Short summary
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It is important to understand how ice crystals and cloud droplets form in clouds, as their concentrations and sizes determine the exact radiative properties of the clouds. Normally, ice crystals form from aerosols, but we found evidence for the formation of additional ice crystals from the original ones over a large temperature range within Arctic clouds. In particular, additional ice crystals were formed during collisions of several ice crystals or during the freezing of large cloud droplets.
Layrson J. M. Gonçalves, Simone M. S. C. Coelho, Paulo Y. Kubota, and Dayana C. Souza
Atmos. Chem. Phys., 22, 15509–15526, https://doi.org/10.5194/acp-22-15509-2022, https://doi.org/10.5194/acp-22-15509-2022, 2022
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This research aims to study the environmental conditions that are favorable and not favorable to cloud formation, in this case specifically for the Amazon region. The results found in this research will be used to improve the representation of clouds in numerical models that are used in weather and climate prediction. In general, it is expected that with better knowledge regarding the cloud–radiation interaction, it is possible to make a better forecast of weather and climate.
Claudia Mignani, Lukas Zimmermann, Rigel Kivi, Alexis Berne, and Franz Conen
Atmos. Chem. Phys., 22, 13551–13568, https://doi.org/10.5194/acp-22-13551-2022, https://doi.org/10.5194/acp-22-13551-2022, 2022
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We determined over the course of 8 winter months the phase of clouds associated with snowfall in Northern Finland using radiosondes and observations of ice particle habits at ground level. We found that precipitating clouds were extending from near ground to at least 2.7 km altitude and approximately three-quarters of them were likely glaciated. Possible moisture sources and ice formation processes are discussed.
Alexei Korolev, Paul J. DeMott, Ivan Heckman, Mengistu Wolde, Earle Williams, David J. Smalley, and Michael F. Donovan
Atmos. Chem. Phys., 22, 13103–13113, https://doi.org/10.5194/acp-22-13103-2022, https://doi.org/10.5194/acp-22-13103-2022, 2022
Short summary
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The present study provides the first explicit in situ observation of secondary ice production at temperatures as low as −27 °C, which is well outside the range of the Hallett–Mossop process (−3 to −8 °C). This observation expands our knowledge of the temperature range of initiation of secondary ice in clouds. The obtained results are intended to stimulate laboratory and theoretical studies to develop physically based parameterizations for weather prediction and climate models.
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
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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.
Étienne Vignon, Lea Raillard, Christophe Genthon, Massimo Del Guasta, Andrew J. Heymsfield, Jean-Baptiste Madeleine, and Alexis Berne
Atmos. Chem. Phys., 22, 12857–12872, https://doi.org/10.5194/acp-22-12857-2022, https://doi.org/10.5194/acp-22-12857-2022, 2022
Short summary
Short summary
The near-surface atmosphere over the Antarctic Plateau is cold and pristine and resembles to a certain extent the high troposphere where cirrus clouds form. In this study, we use innovative humidity measurements at Concordia Station to study the formation of ice fogs at temperatures <−40°C. We provide observational evidence that ice fogs can form through the homogeneous freezing of solution aerosols, a common nucleation pathway for cirrus clouds.
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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...
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