Abstract
It is well-recognized that triggering of convective cells through cold
pools is key to the organization of convection. Yet, numerous studies
have found that both the characterization and parameterization of these
effects in numerical models is cumbersome - in part due to the lack of
numerical convergence, $\Delta
x\rightarrow 0$, achieved in typical cloud-resolving
simulators.
Through a comprehensive numerical convergence study we systematically
approach the $\Delta x \rightarrow 0$
limit in a set of idealized large-eddy simulations capturing key cold
pool processes: free propagation, frontal collision and incident merging
of gust fronts.
We characterize at which $\Delta x$ convergence is
achieved for physically relevant quantities, namely accumulated upwards
water mass fluxes, leading front vortical rates, tropospheric moistening
and group velocity.
The understanding gained from this analysis lays the groundwork to
develop robust subgrid models for CP dynamics able to sustain their
growth and combat artificial numerical dissipation and dispersion.