The sensitivity of large‐eddy simulations of shallow cumulus convection to resolution and subgrid model

Results are presented from a series of large‐eddy simulations of shallow cumulus convection, including some at much higher resolution than previously performed. Many of the ensemble‐averaged turbulence statistics which are relevant for mass‐flux parametrization schemes are shown to be reasonably insensitive to increases in resolution, but the cloud fields change markedly. the implications for the best interpretation of large‐eddy simulation results are discussed.

[1]  W. S. Lewellen,et al.  Large-Eddy Boundary Layer Entrainment. , 1998 .

[2]  A. Brown,et al.  Non-local mixing of momentum in the convective boundary layer , 1997 .

[3]  D. Gregory,et al.  Parametrization of momentum transport by convection. I: Theory and cloud modelling results , 1997 .

[4]  A. P. Siebesma,et al.  Model Impacts of Entrainment and Detrainment Rates in Shallow Cumulus Convection. , 1996 .

[5]  A. P. Siebesma,et al.  Evaluation of Parametric Assumptions for Shallow Cumulus Convection , 1995 .

[6]  P. J. Mason,et al.  Large‐eddy simulation of stable atmospheric boundary layers with a revised stochastic subgrid model , 1994 .

[7]  B. P. Leonard,et al.  Positivity-preserving numerical schemes for multidimensional advection , 1993 .

[8]  P. Rowntree,et al.  A Mass Flux Convection Scheme with Representation of Cloud Ensemble Characteristics and Stability-Dependent Closure , 1990 .

[9]  M. Macvean,et al.  Cloud-Top Entrainment Instability through Small-Scale Mixing and Its Parameterization in Numerical Models. , 1990 .

[10]  M. Tiedtke.  A Comprehensive Mass Flux Scheme for Cumulus Parameterization in Large-Scale Models , 1989 .

[11]  P. J. Mason,et al.  On the magnitude of the subgrid-scale eddy coefficient in large-eddy simulations of turbulent channel flow , 1986, Journal of Fluid Mechanics.

[12]  J. Smagorinsky,et al.  GENERAL CIRCULATION EXPERIMENTS WITH THE PRIMITIVE EQUATIONS , 1963 .

[13]  D. Lilly.  On the numerical simulation of buoyant convection , 1962 .

[14]  Steven K. Krueger,et al.  SUMMARY OF PROGRESS AND MAIN ACTIONS / RECOMMENDATIONS FROM THE NINTH MEETING OF THE GEWEX CLOUD SYSTEM STUDY ( GCSS , 2001 .

[15]  T. Nitta.  Observational Determination of Cloud Mass Flux Distributions , 1975 .

[16]  Caskey,et al.  GENERAL CIRCULATION EXPERIMENTS WITH THE PRIMITIVE EQUATIONS I . THE BASIC EXPERIMENT , 1962 .