Computational Domain Size Effects on Large-Eddy Simulations of Precipitating Shallow Cumulus Convection

Idealized large-eddy simulations of shallow convection often utilize horizontally periodic computational domains. The development precipitation in cumulus changes the spatial structure and creates large-scale organization. However, limited domain constrains horizontal variability atmospheric boundary layer. Small domains cannot capture mesoscale layer organization artificially constrain structure. effects size on precipitating are investigated using four domains, ranging from 40×40km2 to 320×320km2 fine grid resolution (40 m). is captured 160×160km2. LES (≤40 km) reproduce flow features, which about 100km long, but mean profiles similar those larger Turbulent fluxes, temperature moisture variances, length scales converged with respect for equal or than Vertical velocity statistics, such as variance spectra, essentially identical all show minor dependence size. Characteristic (i.e., relating organization) wind components, reach an equilibrium after hour 30.