skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Observed and Simulated Variability of Droplet Spectral Dispersion in Convective Clouds Over the Amazon

Journal Article · · Journal of Geophysical Research: Atmospheres
DOI:https://doi.org/10.1029/2021JD035076· OSTI ID:1827478
ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3]; ORCiD logo [4];  [5];  [5]; ORCiD logo [6];  [7]; ORCiD logo [8]; ORCiD logo [9]; ORCiD logo [5]
  1. Multiphase Chemistry Department Max Planck Institute for Chemistry Mainz Germany, Centro de Previsão de Tempo e Estudos Climáticos Instituto Nacional de Pesquisas Espaciais Cachoeira Paulista Brazil
  2. Mesoscale and Microscale Meteorology Laboratory National Center for Atmospheric Research Boulder CO USA
  3. Institute of Physics University of Sao Paulo São Paulo Brazil
  4. Multiphase Chemistry Department Max Planck Institute for Chemistry Mainz Germany, Scripps Institution of Oceanography University of California San Diego La Jolla CA USA, Department of Geology and Geophysics King Saud University Riyadh Saudi Arabia
  5. Multiphase Chemistry Department Max Planck Institute for Chemistry Mainz Germany
  6. Institute of Earth Sciences The Hebrew University of Jerusalem Jerusalem Israel
  7. Centro de Previsão de Tempo e Estudos Climáticos Instituto Nacional de Pesquisas Espaciais Cachoeira Paulista Brazil
  8. Institut für Physik der Atmosphäre Deutsches Zentrum für Luft und Raumfahrt Wessling Germany, Institut für Physik der Atmosphäre Johannes Gutenberg‐Universität Mainz Mainz Germany
  9. Leipziger Institut für Meteorologie Universität Leipzig Leipzig Germany
+ Show Author Affiliations

Abstract In this study, the variability of the spectral dispersion of droplet size distributions (DSDs) in convective clouds is investigated. Analyses are based on aircraft measurements of growing cumuli near the Amazon basin, and on numerical simulations of an idealized ice‐free cumulus. In cleaner clouds, the relative dispersion , defined as the ratio of the standard deviation to the mean value of the droplet diameter, is negatively correlated with the ratio of the cloud water content ( ) to the adiabatic liquid water content ( ), while no strong correlation between and is seen in polluted clouds. Bin microphysics numerical simulations suggest that these contrasting behaviors are associated with the effect of collision‐coalescence in cleaner clouds, and secondary droplet activation in polluted clouds, in addition to the turbulent mixing of parcels that experienced different paths within the cloud. Collision‐coalescence simultaneously broadens the DSDs and decreases , explaining the inverse relationship between and in cleaner clouds. Secondary droplet activation broadens the DSDs but has little direct impact on . The combination of a rather modest DSD broadening due to weak collision‐coalescence with enhanced droplet activation in both diluted and highly undiluted cloud regions may contribute to maintain a relatively uniform within polluted clouds. These findings can be useful for parameterizing the shape parameter ( ) of gamma DSDs in bulk microphysics cloud‐resolving models. It is shown that emulating the observed relationship improves the estimation of the collision‐coalescence rate in bulk microphysics simulations compared to the bin simulations.

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Atmospheric Radiation Measurement (ARM) Data Center
Sponsoring Organization:
USDOE Office of Science (SC), Biological and Environmental Research (BER); Sao Paulo Research Foundation; German Science Foundation (DFG); German Aerospace Center (DLR)
Grant/Contract Number:
DE‐SC0020118; SC0020118; 2014/14497-0; 2016/24562-6; 2019/06988-4; VO1504/7-1
OSTI ID:
1827478
Alternate ID(s):
OSTI ID: 1822358; OSTI ID: 1827480
Journal Information:
Journal of Geophysical Research: Atmospheres, Journal Name: Journal of Geophysical Research: Atmospheres Vol. 126 Journal Issue: 20; ISSN 2169-897X
Publisher:
American Geophysical Union (AGU)Copyright Statement
Country of Publication:
United States
Language:
English

References (119)

The Evolution of Raindrop Spectra. Part II: Collisional Collection/Breakup and Evaporation in a Rainshaft journal November 1989
Sensitivities of Amazonian clouds to aerosols and updraft speed journal January 2017
The Effects of Turbulent Mixing in Clouds journal January 1984
Flow-induced errors in airborne in situ measurements of aerosols and clouds journal January 2020
The convective boundary layer over pasture and forest in Amazonia journal April 2004
Theoretical investigation of mixing in warm clouds – Part 2: Homogeneous mixing journal January 2016
Settling of small particles near vortices and in turbulence journal August 2001
Cloud droplet size distribution broadening during diffusional growth: ripening amplified by deactivation and reactivation journal January 2018
Evidence for Tilted Toroidal Circulations in Cumulus journal June 2007
An Efficient Numerical Solution to the Stochastic Collection Equation journal November 1987
A Numerical Method for Integrating the Kinetic Equation of Coalescence and Breakup of Cloud Droplets journal November 1980
Collisions of Small Drops in a Turbulent Flow. Part III: Relative Droplet Fluxes and Swept Volumes journal August 2006
Dispersion of Droplet Size Distributions in Supercooled Non‐precipitating Stratocumulus from Aircraft Observations Obtained during the Southern Ocean Cloud Radiation Aerosol Transport Experimental Study journal March 2021
Lagrangian condensation microphysics with Twomey CCN activation journal January 2018
Aerosols, Cloud Microphysics, and Fractional Cloudiness journal September 1989
Entrainment and droplet spectral characteristics in convective clouds during transition to monsoon: Entrainment and droplet spectral characteristics journal March 2016
Theoretical analysis of mixing in liquid clouds – Part IV: DSD evolution and mixing diagrams journal January 2018
Entrainment and the Temporal Development of the Microphysies of Convective Clouds journal September 1985
Analytical expression for the relative dispersion of the cloud droplet size distribution journal January 2006
Collision Rates of Cloud Droplets in Turbulent Flow journal July 2005
Precipitation Initiation Mechanisms and Droplet Characteristics of Some Convective Cloud Cores journal August 1968
The Influence of Supersaturation Fluctuations on Droplet Size Spectra Formation journal October 1995
Radiative Impacts on the Growth of Drops within Simulated Marine Stratocumulus. Part II: Solar Zenith Angle Variations journal July 2005
Droplet growth in warm turbulent clouds
  • Devenish, B. J.; Bartello, P.; Brenguier, J. -L.
  • Quarterly Journal of the Royal Meteorological Society, Vol. 138, Issue 667 https://doi.org/10.1002/qj.1897
journal February 2012
The cloud, aerosol and precipitation spectrometer: a new instrument for cloud investigations journal October 2001
A Double-Moment Multiple-Phase Four-Class Bulk Ice Scheme. Part I: Description journal January 1994
Observations of the width of cloud droplet spectra in stratocumulus journal January 2006
Microphysical properties of synoptic-scale polar stratospheric clouds: in situ measurements of unexpectedly large HNO 3 -containing particles in the Arctic vortex journal January 2014
Collisions of Cloud Droplets in a Turbulent Flow. Part IV: Droplet Hydrodynamic Interaction journal July 2007
Effects of turbulence on the geometric collision rate of sedimenting droplets. Part 1. Results from direct numerical simulation journal July 2008
Radiative influences on ice crystal and droplet growth within mixed-phase stratus clouds journal January 2008
Effects of turbulence on the geometric collision rate of sedimenting droplets. Part 2. Theory and parameterization journal July 2008
Representation of microphysical processes in cloud-resolving models: Spectral (bin) microphysics versus bulk parameterization: BIN VS BULK journal May 2015
The Spurious Production of Cloud-Edge Supersaturations by Eulerian Models journal May 1996
The Marine Stratus/Stratocumulus Experiment (MASE): Aerosol-cloud relationships in marine stratocumulus: MASE-AEROSOL-CLOUD RELATIONSHIPS journal May 2007
Turbulent collision efficiency of heavy particles relevant to cloud droplets journal July 2008
Volatility and size of cloud condensation nuclei journal February 1996
Linear relation between convective cloud drop number concentration and depth for rain initiation: DROP CONCENTRATION AND RAIN INITIATION journal January 2012
Bulk Parameterization of the Snow Field in a Cloud Model journal June 1983
Sources and properties of Amazonian aerosol particles journal January 2010
Elements of the Microphysical Structure of Numerically Simulated Nonprecipitating Stratocumulus journal April 1996
Theoretical analysis of mixing in liquid clouds – Part 3: Inhomogeneous mixing journal January 2016
Dispersion bias, dispersion effect, and the aerosol–cloud conundrum journal October 2008
Empirical relationship between entrainment rate and microphysics in cumulus clouds: ENTRAINMENT RATE AND MICROPHYSICS journal May 2013
Aerosol indirect effect from turbulence-induced broadening of cloud-droplet size distributions journal November 2016
Parametric representation of the cloud droplet spectra for LES warm bulk microphysical schemes journal January 2010
Droplet inhomogeneity in shallow cumuli: the effects of in-cloud location and aerosol number concentration journal January 2019
Coincidence Errors in a Cloud Droplet Probe (CDP) and a Cloud and Aerosol Spectrometer (CAS), and the Improved Performance of a Modified CDP journal October 2012
Theoretical study of mixing in liquid clouds – Part 1: Classical concepts journal January 2016
Composite Vertical Structure of Vertical Velocity in Nonprecipitating Cumulus Clouds journal May 2013
The Evolution of Droplet Spectra and the Rate of Production of Embryonic Raindrops in Small Cumulus Clouds journal August 1979
The super-droplet method for the numerical simulation of clouds and precipitation: a particle-based and probabilistic microphysics model coupled with a non-hydrostatic model journal July 2009
A Cumulus Cloud Microphysics Parameterization for Cloud-Resolving Models journal May 2013
Confronting the Challenge of Modeling Cloud and Precipitation Microphysics journal July 2020
Drop Size Distribution Broadening Mechanisms in a Bin Microphysics Eulerian Model journal September 2020
Radiative Impacts on the Growth of Drops within Simulated Marine Stratocumulus. Part I: Maximum Solar Heating journal July 2005
Evolution of Raindrop Spectra. Part I: Solution to the Stochastic Collection/Breakup Equation Using the Method of Moments journal November 1988
Comparison of Bulk and Bin Warm-Rain Microphysics Models Using a Kinematic Framework journal August 2007
Broadening of droplet size distributions from entrainment and mixing in a cumulus cloud
  • Lasher-Trapp, Sonia G.; Cooper, William A.; Blyth, Alan M.
  • Quarterly Journal of the Royal Meteorological Society, Vol. 131, Issue 605 https://doi.org/10.1256/qj.03.199
journal January 2005
Broadening of Modeled Cloud Droplet Spectra Using Bin Microphysics in an Eulerian Spatial Domain journal November 2018
Toward Cloud Resolving Modeling of Large-Scale Tropical Circulations: A Simple Cloud Microphysics Parameterization journal November 1998
Indirect warming effect from dispersion forcing journal October 2002
Water droplet calibration of the Cloud Droplet Probe (CDP) and in-flight performance in liquid, ice and mixed-phase clouds during ARCPAC journal January 2010
Illustration of microphysical processes in Amazonian deep convective clouds in the gamma phase space: introduction and potential applications journal January 2017
Impact of Cloud Microphysics on the Development of Trailing Stratiform Precipitation in a Simulated Squall Line: Comparison of One- and Two-Moment Schemes journal March 2009
Cloud condensation nuclei in pristine tropical rainforest air of Amazonia: size-resolved measurements and modeling of atmospheric aerosol composition and CCN activity journal January 2009
Influence of Turbulent Fluctuations on Cloud Droplet Size Dispersion and Aerosol Indirect Effects journal September 2018
Cloud Droplet Size Distributions in Low-Level Stratiform Clouds journal January 2000
A New Cloud Physics Parameterization in a Large-Eddy Simulation Model of Marine Stratocumulus journal January 2000
Clustering of settling charged particles in turbulence: theory and experiments journal December 2010
The Geometry of Rimed Aggregate Snowflakes: A Modeling Study journal March 2019
The effects of giant cloud condensation nuclei on the development of precipitation in convective clouds — a numerical study journal March 2000
Calibration of 3-D wind measurements on a single-engine research aircraft journal January 2015
Effects of entrainment and mixing on droplet size distributions in warm cumulus clouds journal April 2014
The Measurement and Parameterization of Effective Radius of Droplets in Warm Stratocumulus Clouds journal July 1994
The Microstructure and Colloidal Stability of Warm Clouds journal May 1958
Toward the Mitigation of Spurious Cloud-Edge Supersaturation in Cloud Models journal March 2008
Growth of Cloud Droplets in a Turbulent Environment journal January 2013
Effects of in-cloud nucleation and turbulence on droplet spectrum formation in cumulus clouds journal January 2002
A two-moment cloud microphysics parameterization for mixed-phase clouds. Part 1: Model description journal October 2005
Cumulus Entrainment and Cloud Droplet Spectra: A Numerical Model within a Two-Dimensional Dynamical Framework journal January 1993
Entrainment in Cumulus Clouds journal April 1993
Life Cycle of Numerically Simulated Shallow Cumulus Clouds. Part II: Mixing Dynamics journal May 2005
The influence of entrainment on the evolution of cloud droplet spectra: I. A model of inhomogeneous mixing journal July 1980
Toward the Theory of Stochastic Condensation in Clouds. Part II: Analytical Solutions of the Gamma-Distribution Type journal December 1999
Impact of entrainment-mixing and turbulent fluctuations on droplet size distributions in a cumulus cloud: An investigation using Lagrangian microphysics with a sub-grid-scale model journal July 2021
Scale Dependence of Cloud Microphysical Response to Turbulent Entrainment and Mixing journal November 2018
Modeling Supersaturation and Subgrid-Scale Mixing with Two-Moment Bulk Warm Microphysics journal March 2008
Further evidence for CCN aerosol concentrations determining the height of warm rain and ice initiation in convective clouds over the Amazon basin journal January 2017
Sensitivity study of the spectral dispersion of the cloud droplet size distribution on the indirect aerosol effect: CLOUD DROPLET DISPERSION EFFECT journal May 2003
The Effect of Spurious Cloud Edge Supersaturations in Lagrangian Cloud Models: An Analytical and Numerical Study journal January 2016
Sensitivity of the First Indirect Aerosol Effect to an Increase of Cloud Droplet Spectral Dispersion with Droplet Number Concentration journal November 2003
Nonlinear Advection Algorithms Applied to Interrelated Tracers: Errors and Implications for Modeling Aerosol–Cloud Interactions journal February 2009
Long-term observations of cloud condensation nuclei over the Amazon rain forest – Part 2: Variability and characteristics of biomass burning, long-range transport, and pristine rain forest aerosols journal January 2018
Reconciling Contrasting Relationships Between Relative Dispersion and Volume‐Mean Radius of Cloud Droplet Size Distributions journal May 2020
A single parameter representation of hygroscopic growth and cloud condensation nucleus activity journal January 2007
ACRIDICON–CHUVA Campaign: Studying Tropical Deep Convective Clouds and Precipitation over Amazonia Using the New German Research Aircraft HALO journal October 2016
Thermodynamic correction of particle concentrations measured by underwing probes on fast-flying aircraft journal January 2016
The Simulation of a Convective Cloud in a 3-D Model With Explicit Microphysics. Part I: Model Description and Sensitivity Experiments journal May 1991
Entrainment of aerosols and their activation in a shallow cumulus cloud studied with a coupled LCM–LES approach journal April 2015
Long-term observations of cloud condensation nuclei in the Amazon rain forest – Part 1: Aerosol size distribution, hygroscopicity, and new model parametrizations for CCN prediction journal January 2016
Condensational Growth of Drops Formed on Giant Sea-Salt Aerosol Particles journal March 2017
An Analysis of Cloud Drop Growth by Collection: Part I. Double Distributions journal October 1974
The role of the gamma function shape parameter in determining differences between condensation rates in bin and bulk microphysics schemes journal January 2017
Parameterizations of Entrainment‐Mixing Mechanisms and Their Effects on Cloud Droplet Spectral Width Based on Numerical Simulations journal November 2020
New understanding and quantification of the regime dependence of aerosol-cloud interaction for studying aerosol indirect effects: Aerosol-Cloud Interaction Regimes journal February 2016
Impact of secondary droplet activation on the contrasting cloud microphysical relationships during the wet and dry seasons in the Amazon journal December 2019
Observational study of the relationship between entrainment rate and relative dispersion in deep convective clouds journal January 2018
Turbulence Effects of Collision Efficiency and Broadening of Droplet Size Distribution in Cumulus Clouds journal January 2018
The Influence of Entrainment and Mixing on the Initial Formation of Rain in a Warm Cumulus Cloud journal June 2013
The Microstructure and Colloidal Stability of Warm Clouds journal May 1958
Effects of Variable Droplet Growth Histories on Droplet Size Distributions. Part I: Theory journal May 1989
Analytical Solutions to the Stochastic Kinetic Equation for Liquid and Ice Particle Size Spectra. Part I: Small-Size Fraction journal July 2008
Aerosol- and updraft-limited regimes of cloud droplet formation: influence of particle number, size and hygroscopicity on the activation of cloud condensation nuclei (CCN) journal January 2009
Height Dependency of Aerosol-Cloud Interaction Regimes: Height Dependency of ACI Regime journal January 2018
Airborne instruments to measure atmospheric aerosol particles, clouds and radiation: A cook's tour of mature and emerging technology journal October 2011
Upshear and Downshear Evolution of Cloud Structure and Spectral Properties journal May 1997
The mechanism of first raindrops formation in deep convective clouds: RAIN ONSET journal August 2013
Laboratory studies of the effects of mixing on the evolution of cloud droplet spectra journal April 1977

Similar Records

Theoretical analysis of non‐ G aussian heterogeneity effects on subsurface flow and transport
Journal Article · Tue Apr 11 00:00:00 EDT 2017 · Water Resources Research · OSTI ID:1827478
Scaling Behavior of Thermally Driven Fractures in Deep Low‐Permeability Formations: A Plane Strain Model With 1‐D Heat Conduction
Journal Article · Thu Feb 24 00:00:00 EST 2022 · Journal of Geophysical Research. Solid Earth · OSTI ID:1827478
Mechanism of Fast Atmospheric Energetic Equilibration Following Radiative Forcing by CO 2
Journal Article · Fri Nov 10 00:00:00 EST 2017 · Journal of Advances in Modeling Earth Systems · OSTI ID:1827478

Related Subjects

54 ENVIRONMENTAL SCIENCES