Articles | Volume 16, issue 14
https://doi.org/10.5194/acp-16-9235-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-16-9235-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
28 Jul 2016
Research article |
| 28 Jul 2016
Theoretical study of mixing in liquid clouds – Part 1: Classical concepts
Environment and Climate Change Canada, Cloud Physics and Severe Weather Section,
Toronto, Canada
Alex Khain
Department of Atmospheric Sciences, the Hebrew University of
Jerusalem, Jerusalem, Israel
Mark Pinsky
Department of Atmospheric Sciences, the Hebrew University of
Jerusalem, Jerusalem, Israel
Jeffrey French
University of Wyoming, Laramie, WY, USA
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Haoran Li, Alexei Korolev, and Dmitri Moisseev
Atmos. Chem. Phys., 21, 13593–13608, https://doi.org/10.5194/acp-21-13593-2021, https://doi.org/10.5194/acp-21-13593-2021, 2021
Short summary
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Kelvin–Helmholtz (K–H) clouds embedded in a stratiform precipitation event were uncovered via radar Doppler spectral analysis. Given the unprecedented detail of the observations, we show that multiple populations of secondary ice columns were generated in the pockets where larger cloud droplets are formed and not at some constant level within the cloud. Our results highlight that the K–H instability is favorable for liquid droplet growth and secondary ice formation.
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
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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.
Alexei Korolev and Thomas Leisner
Atmos. Chem. Phys., 20, 11767–11797, https://doi.org/10.5194/acp-20-11767-2020, https://doi.org/10.5194/acp-20-11767-2020, 2020
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Secondary ice production (SIP) plays a key role in the formation of ice particles in tropospheric clouds. This work presents a critical review of the laboratory studies related to secondary ice production. It aims to identify gaps in our knowledge of SIP as well as to stimulate further laboratory studies focused on obtaining a quantitative description of efficiencies for each SIP mechanism.
Adam Majewski and Jeffrey R. French
Atmos. Chem. Phys., 20, 5035–5054, https://doi.org/10.5194/acp-20-5035-2020, https://doi.org/10.5194/acp-20-5035-2020, 2020
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The study reports formation of supercooled drizzle drops in response to repeating kilometer-wide updrafts and downdrafts within a mixed-phase, mountain-layer cloud containing very little ice despite cold cloud top temperatures (T ~ -30°C). The discrete, embedded hydrometeor growth layers and downwind transition to drizzle production at cloud top indicates the relative importance of kinematic mechanisms in determining the location of precipitation development in cloud.
Alexei Korolev, Ivan Heckman, Mengistu Wolde, Andrew S. Ackerman, Ann M. Fridlind, Luis A. Ladino, R. Paul Lawson, Jason Milbrandt, and Earle Williams
Atmos. Chem. Phys., 20, 1391–1429, https://doi.org/10.5194/acp-20-1391-2020, https://doi.org/10.5194/acp-20-1391-2020, 2020
Short summary
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This study attempts identification of mechanisms of secondary ice production (SIP) based on the observation of small faceted ice crystals. It was found that in both mesoscale convective systems and frontal clouds, SIP was observed right above the melting layer and extended to the higher altitudes with colder temperatures. A principal conclusion of this work is that the freezing drop shattering mechanism is plausibly accounting for the measured ice concentrations in the observed condition.
Cuong M. Nguyen, Mengistu Wolde, and Alexei Korolev
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Robert Jackson, Jeffrey R. French, David C. Leon, David M. Plummer, Sonia Lasher-Trapp, Alan M. Blyth, and Alexei Korolev
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Spencer Faber, Jeffrey R. French, and Robert Jackson
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In this paper it is shown that the difference between the mixing diagrams for homogeneous and inhomogeneous mixing is insignificant and decreases with an increase in the DSD width. If the normalized droplet concentration is used, mixing diagrams do not show any significant dependency on relative humidity in the dry volume.
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Eyal Ilotoviz and Alexander Khain
Atmos. Chem. Phys., 16, 14317–14329, https://doi.org/10.5194/acp-16-14317-2016, https://doi.org/10.5194/acp-16-14317-2016, 2016
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In this paper the evolution of deep convective clouds is simulated under different aerosol loading. The simulations are performed using a spectral-bin microphysics model in which droplet concentration at cloud base is calculated using a new analytical method. The effect of this accurate calculation of droplet concentration is analyzed by comparison with a standard method. The role of the smallest CCN in the aerosol spectra is investigated.
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Atmos. Chem. Phys., 16, 11107–11124, https://doi.org/10.5194/acp-16-11107-2016, https://doi.org/10.5194/acp-16-11107-2016, 2016
Short summary
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Thought to be mostly unimportant for summertime Arctic liquid-water clouds, airborne observations show that atmospheric aerosol particles 50 nm in diameter or smaller and most likely from natural sources are often involved in cloud formation in the pristine Arctic summer. The result expands the reference for aerosol forcing of climate. Further, for extremely low droplet concentrations, no evidence is found for a connection between cloud liquid water and aerosol particle concentrations.
Jing Yang, Zhien Wang, Andrew J. Heymsfield, and Jeffrey R. French
Atmos. Chem. Phys., 16, 10159–10173, https://doi.org/10.5194/acp-16-10159-2016, https://doi.org/10.5194/acp-16-10159-2016, 2016
Short summary
Short summary
This study provides statistics of the vertical air motion characteristics in convective clouds using aircraft in situ measurements from three field campaigns. Small-scale drafts are frequently observed and make important contributions to total air mass flux. The probability density functions and profiles of the observed vertical velocity and air mass flux are provided. The differences among the three field campaigns are compared. Factors influencing the vertical air motions are discussed.
Mark Pinsky, Alexander Khain, Alexei Korolev, and Leehi Magaritz-Ronen
Atmos. Chem. Phys., 16, 9255–9272, https://doi.org/10.5194/acp-16-9255-2016, https://doi.org/10.5194/acp-16-9255-2016, 2016
Short summary
Short summary
The evolution of monodisperse and polydisperse droplet size distributions (DSDs) during
homogeneous mixing is analyzed. It is shown that the classic conceptual scheme, according to which homogeneous mixing leads to a decrease in the droplet mass under constant droplet concentration, is valid only in cases of initially very narrow DSDs. In cases of wide DSDs a decrease of both mass and concentration take place such that the characteristic droplet sizes remain nearly constant.
Mark Pinsky, Alexander Khain, and Alexei Korolev
Atmos. Chem. Phys., 16, 9273–9297, https://doi.org/10.5194/acp-16-9273-2016, https://doi.org/10.5194/acp-16-9273-2016, 2016
Short summary
Short summary
An idealized diffusion--evaporation model of time-dependent mixing between cloud and non-cloud volumes is analyzed. It is shown that the evolution of microphysical variables and the final equilibrium stage are unambiguously determined by two non-dimensional parameters. Delimitation between the types of mixing on the plane of these parameters is carried out. The definitions of homogeneous and inhomogeneous mixings are reconsidered and clarified. Results are compared with the classical concept.
L. Magaritz-Ronen, M. Pinsky, and A. Khain
Atmos. Chem. Phys., 16, 1849–1862, https://doi.org/10.5194/acp-16-1849-2016, https://doi.org/10.5194/acp-16-1849-2016, 2016
Short summary
Short summary
The mechanism of drizzle formation in shallow stratocumulus clouds and the effect of turbulent mixing on this process are investigated using a Lagrangian-Eularian model of the cloud-topped boundary layer. It was found that first large drops form in volumes that are closest to adiabatic with extended residence near cloud top, and maximum values of LWC. Turbulent mixing was found able to delay the process of drizzle initiation but is essential for the further development of drizzle in the cloud.
J. W. Taylor, T. W. Choularton, A. M. Blyth, Z. Liu, K. N. Bower, J. Crosier, M. W. Gallagher, P. I. Williams, J. R. Dorsey, M. J. Flynn, L. J. Bennett, Y. Huang, J. French, A. Korolev, and P. R. A. Brown
Atmos. Chem. Phys., 16, 799–826, https://doi.org/10.5194/acp-16-799-2016, https://doi.org/10.5194/acp-16-799-2016, 2016
Short summary
Short summary
We present microphysical observations of cumulus clouds measured over south-west England during COPE in summer 2013. Detailed sampling focused on an isolated liquid cloud that glaciated as it matured to merge with a band of cloud downwind. The first ice particles observed were frozen drizzle, while columnar ice dominated in the mature stages. We discuss the interactions between the warm rain and secondary ice processes, and their importance for the formation of precipitation.
A. M. Fridlind, A. S. Ackerman, A. Grandin, F. Dezitter, M. Weber, J. W. Strapp, A. V. Korolev, and C. R. Williams
Atmos. Chem. Phys., 15, 11713–11728, https://doi.org/10.5194/acp-15-11713-2015, https://doi.org/10.5194/acp-15-11713-2015, 2015
Short summary
Short summary
Airbus measurements at elevations circa 11 km within large storm systems near Darwin and Santiago indicate ice mass distributed over area-equivalent diameters of 100-500 µm. Profiler-observed radar reflectivity and mean Doppler velocity under similar conditions are found to be consistent with measurements and with 1D simulations of steady-state stratiform rain columns initialized with observed ice size distributions. Results motivate investigation of ice formation pathways in Part II.
A. S. Ackerman, A. M. Fridlind, A. Grandin, F. Dezitter, M. Weber, J. W. Strapp, and A. V. Korolev
Atmos. Chem. Phys., 15, 11729–11751, https://doi.org/10.5194/acp-15-11729-2015, https://doi.org/10.5194/acp-15-11729-2015, 2015
Short summary
Short summary
An updraft parcel model with size-resolved microphysics is used to investigate microphysical pathways leading to ice water content > 2 g m-3 with mass median area-equivalent diameter of 200-300 micron reported at ~11 km in tropical deep convection. Parcel simulations require substantial source of small crystals at temperatures > ~-10 deg C growing by vapor deposition. Warm rain in weaker updrafts surprisingly leads to greater ice mass owing to reduced competition for available water vapor.
A. Korolev and P. R. Field
Atmos. Meas. Tech., 8, 761–777, https://doi.org/10.5194/amt-8-761-2015, https://doi.org/10.5194/amt-8-761-2015, 2015
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Subject: Clouds and Precipitation | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Aerosol impacts on the entrainment efficiency of Arctic mixed-phase convection in a simulated air mass over open water
Evaluating Arctic clouds modelled with the Unified Model and Integrated Forecasting System
Evaluation of aerosol–cloud interactions in E3SM using a Lagrangian framework
Impact of formulations of the homogeneous nucleation rate on ice nucleation events in cirrus
Temperature and cloud condensation nuclei (CCN) sensitivity of orographic precipitation enhanced by a mixed-phase seeder–feeder mechanism: a case study for the 2015 Cumbria flood
Aerosol–precipitation elevation dependence over the central Himalayas using cloud-resolving WRF-Chem numerical modeling
Machine learning of cloud types in satellite observations and climate models
A modeling study of an extreme rainfall event along the northern coast of Taiwan on 2 June 2017
Long-term upper-troposphere climatology of potential contrail occurrence over the Paris area derived from radiosonde observations
Equilibrium climate sensitivity increases with aerosol concentration due to changes in precipitation efficiency
Aerosol-cloud impacts on aerosol detrainment and rainout in shallow maritime tropical clouds
Southern Ocean cloud and shortwave radiation biases in a nudged climate model simulation: does the model ever get it right?
Aerosol characteristics and polarimetric signatures for a deep convective storm over the northwestern part of Europe – modeling and observations
Mixed-phase Direct Numerical Simulation: Ice Growth in Cloud-Top Generating Cells
Evaluation of tropical water vapour from CMIP6 global climate models using the ESA CCI Water Vapour climate data records
Aerosol–stratocumulus interactions: towards a better process understanding using closures between observations and large eddy simulations
The impacts of secondary ice production on microphysics and dynamics in tropical convection
Cloud adjustments from large-scale smoke–circulation interactions strongly modulate the southeastern Atlantic stratocumulus-to-cumulus transition
The influence of multiple groups of biological ice nucleating particles on microphysical properties of mixed-phase clouds observed during MC3E
Quantifying vertical wind shear effects in shallow cumulus clouds over Amazonia
Cirrus cloud thinning using a more physically based ice microphysics scheme in the ECHAM-HAM general circulation model
Impacts of combined microphysical and land-surface uncertainties on convective clouds and precipitation in different weather regimes
Weakening of tropical sea breeze convective systems through interactions of aerosol, radiation, and soil moisture
Sensitivity analysis of an aerosol-aware microphysics scheme in Weather Research and Forecasting (WRF) during case studies of fog in Namibia
Do Arctic mixed-phase clouds sometimes dissipate due to insufficient aerosol? Evidence from comparisons between observations and idealized simulations
Contrail formation within cirrus: ICON-LEM simulations of the impact of cirrus cloud properties on contrail formation
Impact of Holuhraun volcano aerosols on clouds in cloud-system-resolving simulations
Warm and moist air intrusions into the winter Arctic: a Lagrangian view on the near-surface energy budgets
Convective updrafts near sea-breeze fronts
Evaluation of modelled summertime convective storms using polarimetric radar observations
Evaluating seasonal and regional distribution of snowfall in regional climate model simulations in the Arctic
Modeling impacts of ice-nucleating particles from marine aerosols on mixed-phase orographic clouds during 2015 ACAPEX field campaign
Influences of an entrainment–mixing parameterization on numerical simulations of cumulus and stratocumulus clouds
Investigation of ice cloud modeling capabilities for the irregularly shaped Voronoi ice scattering models in climate simulations
Assessing the potential for simplification in global climate model cloud microphysics
Technical note: Parameterising cloud base updraft velocity of marine stratocumuli
Radiative and microphysical responses of clouds to an anomalous increase in fire particles over the Maritime Continent in 2015
Intricate relations among particle collision, relative motion and clustering in turbulent clouds: computational observation and theory
The effect of marine ice-nucleating particles on mixed-phase clouds
A strong statistical link between aerosol indirect effects and the self-similarity of rainfall distributions
Quantifying albedo susceptibility biases in shallow clouds
Primary and secondary ice production: interactions and their relative importance
Microphysical processes producing high ice water contents (HIWCs) in tropical convective clouds during the HAIC-HIWC field campaign: dominant role of secondary ice production
Importance of aerosols and shape of the cloud droplet size distribution for convective clouds and precipitation
Secondary ice production processes in wintertime alpine mixed-phase clouds
Multi-thermals and high concentrations of secondary ice: a modelling study of convective clouds during the Ice in Clouds Experiment – Dust (ICE-D) campaign
Subgrid-scale horizontal and vertical variation of cloud water in stratocumulus clouds: a case study based on LES and comparisons with in situ observations
A vertical transport window of water vapor in the troposphere over the Tibetan Plateau with implications for global climate change
Box model trajectory studies of contrail formation using a particle-based cloud microphysics scheme
Updraft dynamics and microphysics: on the added value of the cumulus thermal reference frame in simulations of aerosol–deep convection interactions
Jan Chylik, Dmitry Chechin, Regis Dupuy, Birte S. Kulla, Christof Lüpkes, Stephan Mertes, Mario Mech, and Roel A. J. Neggers
Atmos. Chem. Phys., 23, 4903–4929, https://doi.org/10.5194/acp-23-4903-2023, https://doi.org/10.5194/acp-23-4903-2023, 2023
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Arctic low-level clouds play an important role in the ongoing warming of the Arctic. Unfortunately, these clouds are not properly represented in weather forecast and climate models. This study tries to cover this gap by focusing on clouds over open water during the spring, observed by research aircraft near Svalbard. The study combines the high-resolution model with sets of observational data. The results show the importance of processes that involve both ice and the liquid water in the clouds.
Gillian Young McCusker, Jutta Vüllers, Peggy Achtert, Paul Field, Jonathan J. Day, Richard Forbes, Ruth Price, Ewan O'Connor, Michael Tjernström, John Prytherch, Ryan Neely III, and Ian M. Brooks
Atmos. Chem. Phys., 23, 4819–4847, https://doi.org/10.5194/acp-23-4819-2023, https://doi.org/10.5194/acp-23-4819-2023, 2023
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In this study, we show that recent versions of two atmospheric models – the Unified Model and Integrated Forecasting System – overestimate Arctic cloud fraction within the lower troposphere by comparison with recent remote-sensing measurements made during the Arctic Ocean 2018 expedition. The overabundance of cloud is interlinked with the modelled thermodynamic structure, with strong negative temperature biases coincident with these overestimated cloud layers.
Matthew W. Christensen, Po-Lun Ma, Peng Wu, Adam C. Varble, Johannes Mülmenstädt, and Jerome D. Fast
Atmos. Chem. Phys., 23, 2789–2812, https://doi.org/10.5194/acp-23-2789-2023, https://doi.org/10.5194/acp-23-2789-2023, 2023
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An increase in aerosol concentration (tiny airborne particles) is shown to suppress rainfall and increase the abundance of droplets in clouds passing over Graciosa Island in the Azores. Cloud drops remain affected by aerosol for several days across thousands of kilometers in satellite data. Simulations from an Earth system model show good agreement, but differences in the amount of cloud water and its extent remain despite modifications to model parameters that control the warm-rain process.
Peter Spichtinger, Patrik Marschalik, and Manuel Baumgartner
Atmos. Chem. Phys., 23, 2035–2060, https://doi.org/10.5194/acp-23-2035-2023, https://doi.org/10.5194/acp-23-2035-2023, 2023
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We investigate the impact of the homogeneous nucleation rate on nucleation events in cirrus. As long as the slope of the rate is represented sufficiently well, the resulting ice crystal number concentrations are not crucially affected. Even a change in the prefactor over orders of magnitude does not change the results. However, the maximum supersaturation during nucleation events shows strong changes. This quantity should be used for diagnostics instead of the popular nucleation threshold.
Julia Thomas, Andrew Barrett, and Corinna Hoose
Atmos. Chem. Phys., 23, 1987–2002, https://doi.org/10.5194/acp-23-1987-2023, https://doi.org/10.5194/acp-23-1987-2023, 2023
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We study the sensitivity of rain formation processes during a heavy-rainfall event over mountains to changes in temperature and pollution. Total rainfall increases by 2 % K−1, and a 6 % K−1 increase is found at the highest altitudes, caused by a mixed-phase seeder–feeder mechanism (frozen cloud particles melt and grow further as they fall through a liquid cloud layer). In a cleaner atmosphere this process is enhanced. Thus the risk of severe rainfall in mountains may increase in the future.
Pramod Adhikari and John F. Mejia
Atmos. Chem. Phys., 23, 1019–1042, https://doi.org/10.5194/acp-23-1019-2023, https://doi.org/10.5194/acp-23-1019-2023, 2023
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We used an atmospheric model to assess the impact of aerosols through radiation and cloud interaction on elevation-dependent precipitation and surface temperature over the central Himalayan region. Results showed contrasting altitudinal precipitation responses to the increased aerosol concentration, which can significantly impact the hydroclimate of the central Himalayas, increasing the risk for extreme events and influencing the regional supply of water resources.
Peter Kuma, Frida A.-M. Bender, Alex Schuddeboom, Adrian J. McDonald, and Øyvind Seland
Atmos. Chem. Phys., 23, 523–549, https://doi.org/10.5194/acp-23-523-2023, https://doi.org/10.5194/acp-23-523-2023, 2023
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We present a machine learning method for determining cloud types in climate model output and satellite observations based on ground observations of cloud genera. We analyse cloud type biases and changes with temperature in climate models and show that the bias is anticorrelated with climate sensitivity. Models simulating decreasing stratiform and increasing cumuliform clouds with increased CO2 concentration tend to have higher climate sensitivity than models simulating the opposite tendencies.
Chung-Chieh Wang, Ting-Yu Yeh, Chih-Sheng Chang, Ming-Siang Li, Kazuhisa Tsuboki, and Ching-Hwang Liu
Atmos. Chem. Phys., 23, 501–521, https://doi.org/10.5194/acp-23-501-2023, https://doi.org/10.5194/acp-23-501-2023, 2023
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The extreme rainfall event (645 mm in 24 h) at the northern coast of Taiwan on 2 June 2017 is studied using a cloud model. Two 1 km experiments with peak amounts of 541 and 400 mm are compared to isolate the reasons for such a difference. It is found that the frontal rainband remains fixed in location for a longer period in the former run due to a low disturbance that acts to focus the near-surface convergence. Therefore, the rainfall is more concentrated and there is a higher total amount.
Kevin Wolf, Nicolas Bellouin, and Olivier Boucher
Atmos. Chem. Phys., 23, 287–309, https://doi.org/10.5194/acp-23-287-2023, https://doi.org/10.5194/acp-23-287-2023, 2023
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Recent studies estimate the radiative impact of contrails to be similar to or larger than that of emitted CO2; thus, contrail mitigation might be an opportunity to reduce the climate effects of aviation. A radiosonde data set is analyzed in terms of the vertical distribution of potential contrails, contrail mitigation by flight altitude changes, and linkages with the tropopause and jet stream. The effect of prospective jet engine developments and alternative fuels are estimated.
Guy Dagan
Atmos. Chem. Phys., 22, 15767–15775, https://doi.org/10.5194/acp-22-15767-2022, https://doi.org/10.5194/acp-22-15767-2022, 2022
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Using idealized simulations we demonstrate that the equilibrium climate sensitivity (ECS), i.e. the increase in surface temperature under equilibrium conditions due to doubling of the CO2 concentration, increases with the aerosol concentration. The ECS increase is explained by a faster increase in precipitation efficiency with warming under high aerosol concentrations, which more efficiently depletes the water from the cloud and thus is manifested as an increase in the cloud feedback parameter.
Gabrielle R. Leung, Stephen M. Saleeby, G. Alexander Sokolowsky, Sean W. Freeman, and Susan C. van den Heever
EGUsphere, https://doi.org/10.5194/egusphere-2022-1406, https://doi.org/10.5194/egusphere-2022-1406, 2022
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This study explores how the concentration and type of aerosol particles impact shallow tropical clouds and the overall aerosol budget. Under more polluted conditions, there are more aerosol particles present, but we also find that clouds are less able to remove those aerosol particles via rainout. Instead, those aerosol particles are more likely to be detrained aloft and remain in the atmosphere for further aerosol-cloud interactions.
Sonya L. Fiddes, Alain Protat, Marc D. Mallet, Simon P. Alexander, and Matthew T. Woodhouse
Atmos. Chem. Phys., 22, 14603–14630, https://doi.org/10.5194/acp-22-14603-2022, https://doi.org/10.5194/acp-22-14603-2022, 2022
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Climate models have difficulty simulating Southern Ocean clouds, impacting how much sunlight reaches the surface. We use machine learning to group different cloud types observed from satellites and simulated in a climate model. We find the model does a poor job of simulating the same cloud type as what the satellite shows and, even when it does, the cloud properties and amount of reflected sunlight are incorrect. We have a lot of work to do to model clouds correctly over the Southern Ocean.
Prabhakar Shrestha, Jana Mendrok, and Dominik Brunner
Atmos. Chem. Phys., 22, 14095–14117, https://doi.org/10.5194/acp-22-14095-2022, https://doi.org/10.5194/acp-22-14095-2022, 2022
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The study extends the Terrestrial Systems Modeling Platform with gas-phase chemistry aerosol dynamics and a radar forward operator to enable detailed studies of aerosol–cloud–precipitation interactions. This is demonstrated using a case study of a deep convective storm, which showed that the strong updraft in the convective core of the storm produced aerosol-tower-like features, which affected the size of the hydrometeors and the simulated polarimetric features (e.g., ZDR and KDP columns).
Sisi Chen, Lulin Xue, Sarah Tessendorf, Kyoko Ikeda, Courtney Weeks, Roy Rasmussen, Melvin Kunkel, Derek Blestrud, Shaun Parkinson, Melinda Meadows, and Nick Dawson
EGUsphere, https://doi.org/10.5194/egusphere-2022-1142, https://doi.org/10.5194/egusphere-2022-1142, 2022
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The possible mechanism of effective ice growth in the cloud-top generating cells in winter orographic clouds is explored using a newly developed ultra-high-resolution cloud microphysics model. Simulations demonstrate that a high availability of moisture and liquid water are critical to producing large ice particles. Fluctuations in temperature and moisture down to millimeter scales due to cloud turbulence can substantially affect the growth history of the individual cloud particles.
Jia He, Helene Brogniez, and Laurence Picon
Atmos. Chem. Phys., 22, 12591–12606, https://doi.org/10.5194/acp-22-12591-2022, https://doi.org/10.5194/acp-22-12591-2022, 2022
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A 2003–2017 satellite-based atmospheric water vapour climate data record is used to assess climate models and reanalyses. The focus is on the tropical belt, whose regional variations in the hydrological cycle are related to the tropospheric overturning circulation. While there are similarities in the interannual variability, the major discrepancies can be explained by the presence of clouds, the representation of moisture fluxes at the surface and cloud processes in the models.
Silvia M. Calderón, Juha Tonttila, Angela Buchholz, Jorma Joutsensaari, Mika Komppula, Ari Leskinen, Liqing Hao, Dmitri Moisseev, Iida Pullinen, Petri Tiitta, Jian Xu, Annele Virtanen, Harri Kokkola, and Sami Romakkaniemi
Atmos. Chem. Phys., 22, 12417–12441, https://doi.org/10.5194/acp-22-12417-2022, https://doi.org/10.5194/acp-22-12417-2022, 2022
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The spatial and temporal restrictions of observations and oversimplified aerosol representation in large eddy simulations (LES) limit our understanding of aerosol–stratocumulus interactions. In this closure study of in situ and remote sensing observations and outputs from UCLALES–SALSA, we have assessed the role of convective overturning and aerosol effects in two cloud events observed at the Puijo SMEAR IV station, Finland, a diurnal-high aerosol case and a nocturnal-low aerosol case.
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
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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.
Michael S. Diamond, Pablo E. Saide, Paquita Zuidema, Andrew S. Ackerman, Sarah J. Doherty, Ann M. Fridlind, Hamish Gordon, Calvin Howes, Jan Kazil, Takanobu Yamaguchi, Jianhao Zhang, Graham Feingold, and Robert Wood
Atmos. Chem. Phys., 22, 12113–12151, https://doi.org/10.5194/acp-22-12113-2022, https://doi.org/10.5194/acp-22-12113-2022, 2022
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Smoke from southern Africa blankets the southeast Atlantic from June-October, overlying a major transition region between overcast and scattered clouds. The smoke affects Earth's radiation budget by absorbing sunlight and changing cloud properties. We investigate these effects in regional climate and large eddy simulation models based on international field campaigns. We find that large-scale circulation changes more strongly affect cloud transitions than smoke microphysical effects in our case.
Sachin Patade, Deepak Waman, Akash Deshmukh, Ashok Kumar Gupta, Arti Jadav, Vaughan T. J. Phillips, Aaron Bansemer, Jacob Carlin, and Alexander Ryzhkov
Atmos. Chem. Phys., 22, 12055–12075, https://doi.org/10.5194/acp-22-12055-2022, https://doi.org/10.5194/acp-22-12055-2022, 2022
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This modeling study focuses on the role of multiple groups of primary biological aerosol particles as ice nuclei on cloud properties and precipitation. This was done by implementing a more realistic scheme for biological ice nucleating particles in the aerosol–cloud model. Results show that biological ice nucleating particles have a limited role in altering the ice phase and precipitation in deep convective clouds.
Micael Amore Cecchini, Marco de Bruine, Jordi Vilà-Guerau de Arellano, and Paulo Artaxo
Atmos. Chem. Phys., 22, 11867–11888, https://doi.org/10.5194/acp-22-11867-2022, https://doi.org/10.5194/acp-22-11867-2022, 2022
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Shallow clouds (vertical extent up to 3 km height) are ubiquitous throughout the Amazon and are responsible for redistributing the solar heat and moisture vertically and horizontally. They are a key component of the water cycle because they can grow past the shallow phase to contribute significantly to the precipitation formation. However, they need favourable environmental conditions to grow. In this study, we analyse how changing wind patterns affect the development of such shallow clouds.
Colin Tully, David Neubauer, Nadja Omanovic, and Ulrike Lohmann
Atmos. Chem. Phys., 22, 11455–11484, https://doi.org/10.5194/acp-22-11455-2022, https://doi.org/10.5194/acp-22-11455-2022, 2022
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The proposed geoengineering method, cirrus cloud thinning, was evaluated using a more physically based microphysics scheme coupled to a more realistic approach for calculating ice cloud fractions in the ECHAM-HAM GCM. Sensitivity tests reveal that using the new ice cloud fraction approach and increasing the critical ice saturation ratio for ice nucleation on seeding particles reduces warming from overseeding. However, this geoengineering method is unlikely to be feasible on a global scale.
Christian Barthlott, Amirmahdi Zarboo, Takumi Matsunobu, and Christian Keil
Atmos. Chem. Phys., 22, 10841–10860, https://doi.org/10.5194/acp-22-10841-2022, https://doi.org/10.5194/acp-22-10841-2022, 2022
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The relevance of microphysical and land-surface uncertainties for convective-scale predictability is evaluated with a combined-perturbation strategy in realistic convection-resolving simulations. We find a large ensemble spread which demonstrates that the uncertainties investigated here and, in particular, their collective effect are highly relevant for quantitative precipitation forecasting of summertime convection in central Europe.
J. Minnie Park and Susan C. van den Heever
Atmos. Chem. Phys., 22, 10527–10549, https://doi.org/10.5194/acp-22-10527-2022, https://doi.org/10.5194/acp-22-10527-2022, 2022
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This study explores how increased aerosol particles impact tropical sea breeze cloud systems under different environments and how a range of environments modulate these cloud responses. Overall, sea breeze flows and clouds that develop therein become weaker due to interactions between aerosols, sunlight, and land surface. In addition, surface rainfall also decreases with more aerosol particles. Weakening of cloud and rain with more aerosols is found irrespective of 130 different environments.
Michael John Weston, Stuart John Piketh, Frédéric Burnet, Stephen Broccardo, Cyrielle Denjean, Thierry Bourrianne, and Paola Formenti
Atmos. Chem. Phys., 22, 10221–10245, https://doi.org/10.5194/acp-22-10221-2022, https://doi.org/10.5194/acp-22-10221-2022, 2022
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An aerosol-aware microphysics scheme is evaluated for fog cases in Namibia. AEROCLO-sA campaign observations are used to access and parameterise the model. The model cloud condensation nuclei activation is lower than the observations. The scheme is designed for clouds with updrafts, while fog typically forms in stable conditions. A pseudo updraft speed assigned to the lowest model levels helps achieve more realistic cloud droplet number concentration and size distribution in the model.
Lucas J. Sterzinger, Joseph Sedlar, Heather Guy, Ryan R. Neely III, and Adele L. Igel
Atmos. Chem. Phys., 22, 8973–8988, https://doi.org/10.5194/acp-22-8973-2022, https://doi.org/10.5194/acp-22-8973-2022, 2022
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Aerosol particles are required for cloud droplets to form, and the Arctic atmosphere often has much fewer aerosols than at lower latitudes. In this study, we investigate whether aerosol concentrations can drop so low as to no longer support a cloud. We use observations to initialize idealized model simulations to investigate a worst-case scenario where all aerosol is removed from the environment instantaneously. We find that this mechanism is possible in two cases and is unlikely in the third.
Pooja Verma and Ulrike Burkhardt
Atmos. Chem. Phys., 22, 8819–8842, https://doi.org/10.5194/acp-22-8819-2022, https://doi.org/10.5194/acp-22-8819-2022, 2022
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This paper investigates contrail ice formation within cirrus and the impact of natural cirrus on the contrail ice formation in the high-resolution ICON-LEM simulations over Germany. Contrail formation often leads to increases in cirrus ice crystal number concentration by a few orders of magnitude. Contrail formation is affected by pre-existing cirrus, leading to changes in contrail formation conditions and ice nucleation rates that can be significant in optically thick cirrus.
Mahnoosh Haghighatnasab, Jan Kretzschmar, Karoline Block, and Johannes Quaas
Atmos. Chem. Phys., 22, 8457–8472, https://doi.org/10.5194/acp-22-8457-2022, https://doi.org/10.5194/acp-22-8457-2022, 2022
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The impact of aerosols emitted by the Holuhraun volcanic eruption on liquid clouds was assessed from a pair of cloud-system-resolving simulations along with satellite retrievals. Inside and outside the plume were compared in terms of their statistical distributions. Analyses indicated enhancement for cloud droplet number concentration inside the volcano plume in model simulations and satellite retrievals, while there was on average a small effect on both liquid water path and cloud fraction.
Cheng You, Michael Tjernström, and Abhay Devasthale
Atmos. Chem. Phys., 22, 8037–8057, https://doi.org/10.5194/acp-22-8037-2022, https://doi.org/10.5194/acp-22-8037-2022, 2022
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In winter when solar radiation is absent in the Arctic, the poleward transport of heat and moisture into the high Arctic becomes the main contribution of Arctic warming. Over completely frozen ocean sectors, total surface energy budget is dominated by net long-wave heat, while over the Barents Sea, with an open ocean to the south, total net surface energy budget is dominated by the surface turbulent heat.
Shizuo Fu, Richard Rotunno, and Huiwen Xue
Atmos. Chem. Phys., 22, 7727–7738, https://doi.org/10.5194/acp-22-7727-2022, https://doi.org/10.5194/acp-22-7727-2022, 2022
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The convective updrafts near the sea-breeze fronts (SBFs) play important roles in initiating deep convection, but their characteristics are not well understood. By performing large-eddy simulations, we explain why the updrafts near the SBF are larger than but have similar strength to the updrafts ahead of the SBF. The results should also apply to other boundary-layer convergence zones similar to the SBF.
Prabhakar Shrestha, Silke Trömel, Raquel Evaristo, and Clemens Simmer
Atmos. Chem. Phys., 22, 7593–7618, https://doi.org/10.5194/acp-22-7593-2022, https://doi.org/10.5194/acp-22-7593-2022, 2022
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The study makes use of ensemble numerical simulations with forward operator to evaluate the simulated cloud and precipitation processes with radar observations. While comparing model data with radar has its own challenges due to errors in the forward operator and processed radar measurements, the model was generally found to underestimate the high reflectivity, width/magnitude (value) of ZDR columns and high precipitation.
Annakaisa von Lerber, Mario Mech, Annette Rinke, Damao Zhang, Melanie Lauer, Ana Radovan, Irina Gorodetskaya, and Susanne Crewell
Atmos. Chem. Phys., 22, 7287–7317, https://doi.org/10.5194/acp-22-7287-2022, https://doi.org/10.5194/acp-22-7287-2022, 2022
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Snowfall is an important climate indicator. However, microphysical snowfall processes are challenging for atmospheric models. In this study, the performance of a regional climate model is evaluated in modeling the spatial and temporal distribution of Arctic snowfall when compared to CloudSat satellite observations. Excellent agreement in averaged annual snowfall rates is found, and the shown methodology offers a promising diagnostic tool to investigate the shown differences further.
Yun Lin, Jiwen Fan, Pengfei Li, Lai-yung Ruby Leung, Paul J. DeMott, Lexie Goldberger, Jennifer Comstock, Ying Liu, Jong-Hoon Jeong, and Jason Tomlinson
Atmos. Chem. Phys., 22, 6749–6771, https://doi.org/10.5194/acp-22-6749-2022, https://doi.org/10.5194/acp-22-6749-2022, 2022
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How sea spray aerosols may affect cloud and precipitation over the region by acting as ice-nucleating particles (INPs) is unknown. We explored the effects of INPs from marine aerosols on orographic cloud and precipitation for an atmospheric river event observed during the 2015 ACAPEX field campaign. The marine INPs enhance the formation of ice and snow, leading to less shallow warm clouds but more mixed-phase and deep clouds. This work suggests models need to consider the impacts of marine INPs.
Xiaoqi Xu, Chunsong Lu, Yangang Liu, Shi Luo, Xin Zhou, Satoshi Endo, Lei Zhu, and Yuan Wang
Atmos. Chem. Phys., 22, 5459–5475, https://doi.org/10.5194/acp-22-5459-2022, https://doi.org/10.5194/acp-22-5459-2022, 2022
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A new entrainment–mixing parameterization which can be directly implemented in microphysics schemes without requiring the relative humidity of the entrained air is proposed based on the explicit mixing parcel model. The parameterization is implemented in the two-moment microphysics scheme and exhibits different effects on different types of clouds and even on different stages of stratocumulus clouds, which are affected by turbulent dissipation rate and aerosol concentration.
Ming Li, Husi Letu, Yiran Peng, Hiroshi Ishimoto, Yanluan Lin, Takashi Y. Nakajima, Anthony J. Baran, Zengyuan Guo, Yonghui Lei, and Jiancheng Shi
Atmos. Chem. Phys., 22, 4809–4825, https://doi.org/10.5194/acp-22-4809-2022, https://doi.org/10.5194/acp-22-4809-2022, 2022
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To build on the previous investigations of the Voronoi model in the remote sensing retrievals of ice cloud products, this paper developed an ice cloud parameterization scheme based on the single-scattering properties of the Voronoi model and evaluate it through simulations with the Community Integrated Earth System Model (CIESM). Compared with four representative ice cloud schemes, results show that the Voronoi model has good capabilities of ice cloud modeling in the climate model.
Ulrike Proske, Sylvaine Ferrachat, David Neubauer, Martin Staab, and Ulrike Lohmann
Atmos. Chem. Phys., 22, 4737–4762, https://doi.org/10.5194/acp-22-4737-2022, https://doi.org/10.5194/acp-22-4737-2022, 2022
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Cloud microphysical processes shape cloud properties and are therefore important to represent in climate models. Their parameterization has grown more complex, making the model results more difficult to interpret. Using sensitivity analysis we test how the global aerosol–climate model ECHAM-HAM reacts to changes to these parameterizations. The model is sensitive to the parameterization of ice crystal autoconversion but not to, e.g., self-collection, suggesting that it may be simplified.
Jaakko Ahola, Tomi Raatikainen, Muzaffer Ege Alper, Jukka-Pekka Keskinen, Harri Kokkola, Antti Kukkurainen, Antti Lipponen, Jia Liu, Kalle Nordling, Antti-Ilari Partanen, Sami Romakkaniemi, Petri Räisänen, Juha Tonttila, and Hannele Korhonen
Atmos. Chem. Phys., 22, 4523–4537, https://doi.org/10.5194/acp-22-4523-2022, https://doi.org/10.5194/acp-22-4523-2022, 2022
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Clouds are important for the climate, and cloud droplets have a significant role in cloud properties. Cloud droplets form when air rises and cools and water vapour condenses on small particles that can be natural or of anthropogenic origin. Currently, the updraft velocity, meaning how fast the air rises, is poorly represented in global climate models. In our study, we show three methods that will improve the depiction of updraft velocity and which properties are vital to updrafts.
Azusa Takeishi and Chien Wang
Atmos. Chem. Phys., 22, 4129–4147, https://doi.org/10.5194/acp-22-4129-2022, https://doi.org/10.5194/acp-22-4129-2022, 2022
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Nanometer- to micrometer-sized particles in the atmosphere, namely aerosols, play a crucial role in cloud formation as cloud droplets form on aerosols. This study uses a weather forecasting model to examine the impacts of a large emission of aerosol particles from biomass burning activities over Southeast Asia. We find that additional cloud droplets brought by fire-emitted particles can lead to taller and more reflective convective clouds with increased rainfall.
Ewe-Wei Saw and Xiaohui Meng
Atmos. Chem. Phys., 22, 3779–3788, https://doi.org/10.5194/acp-22-3779-2022, https://doi.org/10.5194/acp-22-3779-2022, 2022
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Collision–coagulation of small droplets in turbulent clouds leads to the production of rain. Turbulence causes droplet clustering and higher relative droplet velocities, and these should enhance the collision–coagulation rate. We find, surprisingly, that collision–coagulation starkly diminishes clustering and strongly alters relative velocities. We provide a theory that explains this result. Our results call for a new perspective on how we understand particle/droplet collision in clouds.
Tomi Raatikainen, Marje Prank, Jaakko Ahola, Harri Kokkola, Juha Tonttila, and Sami Romakkaniemi
Atmos. Chem. Phys., 22, 3763–3778, https://doi.org/10.5194/acp-22-3763-2022, https://doi.org/10.5194/acp-22-3763-2022, 2022
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Mineral dust or similar ice-nucleating particles (INPs) are needed to initiate cloud droplet freezing at temperatures common in shallow clouds. In this work we examine how INPs that are released from the sea surface impact marine clouds. Our high-resolution simulations show that turbulent updraughts carry these particles effectively up to the clouds, where they initiate cloud droplet freezing. Sea surface INP emissions become more important with decreasing background dust INP concentrations.
Kalli Furtado and Paul Field
Atmos. Chem. Phys., 22, 3391–3407, https://doi.org/10.5194/acp-22-3391-2022, https://doi.org/10.5194/acp-22-3391-2022, 2022
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The complex processes involved mean that no simple answer to this
question has so far been discovered: do aerosols increase or decrease precipitation? Using high-resolution weather simulations, we find a self-similar property of rainfall that is not affected by aerosols. Using this invariant, we can collapse all our simulations to a single curve. So, although aerosol effects on rain are many, there may be a universal constraint on the number of degrees of freedom needed to represent them.
Graham Feingold, Tom Goren, and Takanobu Yamaguchi
Atmos. Chem. Phys., 22, 3303–3319, https://doi.org/10.5194/acp-22-3303-2022, https://doi.org/10.5194/acp-22-3303-2022, 2022
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The evaluation of radiative forcing associated with aerosol–cloud interactions remains a significant source of uncertainty in future climate projections. Using high-resolution numerical model output, we mimic typical satellite retrieval methodologies to show that data aggregation can introduce significant error (hundreds of percent) in the cloud albedo susceptibility metric. Spatial aggregation errors tend to be countered by temporal aggregation errors.
Xi Zhao and Xiaohong Liu
Atmos. Chem. Phys., 22, 2585–2600, https://doi.org/10.5194/acp-22-2585-2022, https://doi.org/10.5194/acp-22-2585-2022, 2022
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The goal of this study is to investigate the relative importance and interactions of primary and secondary ice production in the Arctic mixed-phase clouds. Our results show that the SIP is not only a result of ice crystals produced from ice nucleation, but also competes with the ice production; conversely, strong ice nucleation also suppresses SIP.
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
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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.
Christian Barthlott, Amirmahdi Zarboo, Takumi Matsunobu, and Christian Keil
Atmos. Chem. Phys., 22, 2153–2172, https://doi.org/10.5194/acp-22-2153-2022, https://doi.org/10.5194/acp-22-2153-2022, 2022
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The relative impact of cloud condensation nuclei (CCN) concentrations and the shape parameter of the cloud droplet size distribution is evaluated in realistic convection-resolving simulations. We find that an increase in the shape parameter can produce almost as large a variation in precipitation as a CCN increase from maritime to polluted conditions. The choice of the shape parameter may be more important than previously thought for determining cloud radiative characteristics.
Paraskevi Georgakaki, Georgia Sotiropoulou, Étienne Vignon, Anne-Claire Billault-Roux, Alexis Berne, and Athanasios Nenes
Atmos. Chem. Phys., 22, 1965–1988, https://doi.org/10.5194/acp-22-1965-2022, https://doi.org/10.5194/acp-22-1965-2022, 2022
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The modelling study focuses on the importance of ice multiplication processes in orographic mixed-phase clouds, which is one of the least understood cloud types in the climate system. We show that the consideration of ice seeding and secondary ice production through ice–ice collisional breakup is essential for correct predictions of precipitation in mountainous terrain, with important implications for radiation processes.
Zhiqiang Cui, Alan Blyth, Yahui Huang, Gary Lloyd, Thomas Choularton, Keith Bower, Paul Field, Rachel Hawker, and Lindsay Bennett
Atmos. Chem. Phys., 22, 1649–1667, https://doi.org/10.5194/acp-22-1649-2022, https://doi.org/10.5194/acp-22-1649-2022, 2022
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High concentrations of ice particles were observed at temperatures greater than about –8 C. The default scheme of the secondary ice production cannot explain the high concentrations. Relaxing the conditions for secondary ice production or considering dust aerosol alone is insufficient to produce the observed amount of ice particles. It is likely that multi-thermals play an important role in producing very high concentrations of secondary ice particles in some tropical clouds.
Justin A. Covert, David B. Mechem, and Zhibo Zhang
Atmos. Chem. Phys., 22, 1159–1174, https://doi.org/10.5194/acp-22-1159-2022, https://doi.org/10.5194/acp-22-1159-2022, 2022
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Stratocumulus play an important role in Earth's radiative balance. The simulation of these cloud systems in climate models is difficult due to the scale at which cloud microphysical processes occur compared with model grid sizes. In this study, we use large-eddy simulation to analyze subgrid-scale variability of cloud water and its implications on a cloud water to drizzle model enhancement factor E. We find current values of E may be too large and that E should be vertically dependent in models.
Xiangde Xu, Chan Sun, Deliang Chen, Tianliang Zhao, Jianjun Xu, Shengjun Zhang, Juan Li, Bin Chen, Yang Zhao, Hongxiong Xu, Lili Dong, Xiaoyun Sun, and Yan Zhu
Atmos. Chem. Phys., 22, 1149–1157, https://doi.org/10.5194/acp-22-1149-2022, https://doi.org/10.5194/acp-22-1149-2022, 2022
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A vertical transport window of tropospheric vapor exists on the Tibetan Plateau (TP). The TP's thermal forcing drives the vertical transport
windowof vapor in the troposphere. The effects of the TP's vertical transport window of vapor are of importance in global climate change.
Andreas Bier, Simon Unterstrasser, and Xavier Vancassel
Atmos. Chem. Phys., 22, 823–845, https://doi.org/10.5194/acp-22-823-2022, https://doi.org/10.5194/acp-22-823-2022, 2022
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We investigate contrail formation in an aircraft plume with a particle-based multi-trajectory 0D model. Due to the high plume heterogeneity, contrail ice crystals form first near the plume edge and then in the plume centre. The number of ice crystals varies strongly with ambient conditions and soot properties near the contrail formation threshold. Our results imply that the multi-trajectory approach does not necessarily lead to improved scientific results compared to a single mean trajectory.
Daniel Hernandez-Deckers, Toshihisa Matsui, and Ann M. Fridlind
Atmos. Chem. Phys., 22, 711–724, https://doi.org/10.5194/acp-22-711-2022, https://doi.org/10.5194/acp-22-711-2022, 2022
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We investigate how the concentration of aerosols (small particles that serve as seeds for cloud droplets) affect the dynamics of simulated clouds using two different frameworks, i.e., the traditional selection of cloudy rising grid points and tracking small-scale coherent rising features (cumulus thermals). By doing so, we find that these cumulus thermals reveal useful information about the coupling between internal cloud circulations and cloud droplet and raindrop formation.
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Short summary
Relationships between basic microphysical parameters are studied within the framework of homogeneous and extreme inhomogeneous mixing. Analytical expressions and numerical simulations of relationships between droplet concentration, extinction coefficient, liquid water content, and mean volume droplet size are presented. The obtained relationships between moments are used to identify type of mixing for in situ observations obtained in convective clouds.
Relationships between basic microphysical parameters are studied within the framework of...
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