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Title: Effective Buoyancy, Inertial Pressure, and the Mechanical Generation of Boundary Layer Mass Flux by Cold Pools

Journal Article · · Journal of the Atmospheric Sciences
 [1];  [2]
  1. Univ. of California, Berkeley, CA (United States). Dept. of Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Division
  2. Univ. of California, Berkeley, CA (United States). Dept. of Earth and Planetary Science; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Division
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The Davies-Jones formulation of effective buoyancy is used to define inertial and buoyant components of vertical force and to develop an intuition for these components by considering simple cases. This decomposition is applied to the triggering of new boundary layer mass flux by cold pools in a cloud-resolving simulation of radiative-convective equilibrium (RCE). The triggering is found to be dominated by inertial forces, and this is explained by estimating the ratio of the inertial forcing to the buoyancy forcing, which scales as H/h, where H is the characteristic height of the initial downdraft and h is the characteristic height of the mature cold pool's gust front. In a simulation of the transition from shallow to deep convection, the buoyancy forcing plays a dominant role in triggering mass flux in the shallow regime, but the force balance tips in favor of inertial forcing just as precipitation sets in, consistent with the RCE results.

Research Organization:
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Biological and Environmental Research (BER)
Grant/Contract Number:
AC02-05CH11231
OSTI ID:
1512124
Journal Information:
Journal of the Atmospheric Sciences, Vol. 72, Issue 8; ISSN 0022-4928
Publisher:
American Meteorological SocietyCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 51 works
Citation information provided by
Web of Science

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Cited By (8)

Moisture Distributions in Tropical Cold Pools From Equatorial Indian Ocean Observations and Cloud-Resolving Simulations journal October 2018
Sensitivity of Radiative‐Convection Equilibrium to Divergence Damping in GFDL‐FV3‐Based Cloud‐Resolving Model Simulations journal July 2018
A Numerical Study of Convection Initiation Associated With a Gust Front in Bohai Bay Region, North China journal December 2019
GoAmazon2014/5 campaign points to deep-inflow approach to deep convection across scales journal April 2018
Ongoing Breakthroughs in Convective Parameterization journal April 2019
Tracking the Gust Fronts of Convective Cold Pools journal November 2019
A Survey of Precipitation-Induced Atmospheric Cold Pools over Oceans and Their Interactions with the Larger-Scale Environment journal November 2017
Tracking the Gust Fronts of Convective Cold Pools text January 2020

Figures / Tables (9)

Figure 1(p. 3)figure Figure 1
Figure 2(p. 7)figure Figure 2
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Figure 6(p. 12)figure Figure 6
Figure 7(p. 15)figure Figure 7
Figure 8(p. 16)figure Figure 8
Figure 9(p. 18)figure Figure 9

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Related Subjects

54 ENVIRONMENTAL SCIENCES
Buoyancy
Cold pools
Convective clouds
Deep convection
Dynamics
Gust fronts