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Title: Dependence of entrainment in shallow cumulus convection on vertical velocity and distance to cloud edge

Journal Article · · Geophysical Research Letters
DOI:https://doi.org/10.1002/2016GL069005· OSTI ID:1469308
 [1];  [2]
  1. Harvard Univ., Cambridge, MA (United States). Dept. of Earth and Planetary Sciences
  2. Harvard Univ., Cambridge, MA (United States). John A. Paulson School of Engineering and Applied Sciences and Dept. of Earth and Planetary Sciences
+ Show Author Affiliations

Here, the dependence of entrainment rate on environmental conditions and cloud characteristics is investigated using large eddy simulations (LES) of the response of shallow cumulus convection to a small-amplitude temperature perturbation that is horizontally uniform and localized in height. The simulated cumulus fields are analyzed in the framework of an ensemble of entraining plumes by tracking a large number of Lagrangian parcels embedded in the LES and grouping them into different plumes based on their detrainment heights. The results show that fractional entrainment rate per unit height of a plume is inversely proportional to the plume’s vertical velocity and its distance to the cloud edge, while changes in environmental stratification and relative humidity, the plume’s buoyancy, or the vertical gradient of its buoyancy due to the temperature perturbation have little effect on the plume’s entrainment rate.

Research Organization:
Harvard Univ., Cambridge, MA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Biological and Environmental Research (BER); National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States); National Science Foundation (NSF)
Grant/Contract Number:
SC0008679; NA13OAR4310154; AGS‐1260380
OSTI ID:
1469308
Journal Information:
Geophysical Research Letters, Vol. 43, Issue 8; ISSN 0094-8276
Publisher:
American Geophysical UnionCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 18 works
Citation information provided by
Web of Science

References (36)

Linear Response Functions of a Cumulus Ensemble to Temperature and Moisture Perturbations and Implications for the Dynamics of Convectively Coupled Waves journal April 2010
Simulating deep convection with a shallow convection scheme journal January 2011
A Cumulus Parameterization with State-Dependent Entrainment Rate. Part I: Description and Sensitivity to Temperature and Humidity Profiles journal July 2010
Direct entrainment and detrainment rate distributions of individual shallow cumulus clouds in an LES journal January 2013
Tracer Transport in Deep Convective Updrafts: Plume Ensemble versus Bulk Formulations journal August 2005
Mixing in Shallow Cumulus Clouds Studied by Lagrangian Particle Tracking journal August 2008
The Macroscopic Entrainment Processes of Simulated Cumulus Ensemble. Part II: Testing the Entraining-Plume Model journal April 1997
Cloud-Environment Interface Instability: Part II: Extension to Three Spatial Dimensions journal February 1993
Cloud–Environment Interface Instability: Rising Thermal Calculations in Two Spatial Dimensions journal February 1991
Mechanisms for convection triggering by cold pools journal March 2015
Estimation of entrainment rate in simple models of convective clouds journal January 2001
Modeling of Subgrid-Scale Mixing in Large-Eddy Simulation of Shallow Convection journal July 2009
A Stochastic Mixing Model for Nonprecipitating Cumulus Clouds journal November 1986
Measurements of the Atmospheric Mass, Energy, and Momentum Budgets Over a 500-Kilometer Square of Tropical Ocean journal January 1973
Interaction of a Cumulus Cloud Ensemble with the Large-Scale Environment, Part I journal April 1974
Responses of Shallow Cumulus Convection to Large-Scale Temperature and Moisture Perturbations: A Comparison of Large-Eddy Simulations and a Convective Parameterization Based on Stochastically Entraining Parcels journal June 2012
A Large Eddy Simulation Intercomparison Study of Shallow Cumulus Convection journal May 2003
Measurement of Convective Entrainment Using Lagrangian Particles journal January 2013
Development and Evaluation of a Convection Scheme for Use in Climate Models journal June 1999
Homogeneity of the Subgrid-Scale Turbulent Mixing in Large-Eddy Simulation of Shallow Convection journal September 2013
Models of Precipitating Cumulus Towers journal July 1969
Parameterizing Convective Organization to Escape the Entrainment Dilemma: PARAMETERIZING CONVECTIVE ORGANIZATION journal February 2011
A cloud resolving model as a cloud parameterization in the NCAR Community Climate System Model: Preliminary results journal September 2001
A Direct Measure of Entrainment journal June 2010
Gravity Waves, Compensating Subsidence and Detrainment around Cumulus Clouds journal March 1989
Weakly Forced Mock Walker Cells journal September 2012
The Use of Large-Eddy Simulations in Lagrangian Particle Dispersion Models journal December 2004
Beyond bulk entrainment and detrainment rates: A new framework for diagnosing mixing in cumulus convection: MAPPING FRAMEWORK FOR CONVECTIVE MIXING journal November 2012
Do Undiluted Convective Plumes Exist in the Upper Tropical Troposphere? journal February 2010
The Entrainment Mechanism in Colorado Cumuli journal December 1979
Modeling Entrainment and Finescale Mixing in Cumulus Clouds journal December 1997
Some Bulk Properties of Cumulus Ensembles Simulated by a Cloud-Resolving Model. Part II: Entrainment Profiles journal November 1999
A Mass-Flux Scheme View of a High-Resolution Simulation of a Transition from Shallow to Deep Cumulus Convection journal July 2006
Advances in simulating atmospheric variability with the ECMWF model: From synoptic to decadal time-scales
  • Bechtold, Peter; Köhler, Martin; Jung, Thomas
  • Quarterly Journal of the Royal Meteorological Society, Vol. 134, Issue 634 https://doi.org/10.1002/qj.289
journal July 2008
Shallow Cumulus Convection book January 1998
A similarity hypothesis for shallow-cumulus transports journal July 1999

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The Vertical Momentum Budget of Shallow Cumulus Convection: Insights From a Lagrangian Perspective journal January 2019
Increasing potential for intense tropical and subtropical thunderstorms under global warming journal October 2017

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Related Subjects

54 ENVIRONMENTAL SCIENCES
entrainment
shallow cumulus convection
lagrangian particle dispersion model
cloud-resolving model