A two-fluid single-column model of turbulent shallow convection, Part III: Results and parameter sensitivity

Abstract

Two-fluid modelling has recently emerged as a promising approach to representing cumulus convection in weather and climate models. This study applies the two-fluid model described in Part II (Thuburn et al., 2022b) to a shallow cu- mulus convection case study over land (ARM). Large eddy simulation data is used to tune the majority of the closures that determine the properties of entrained and detrained air. The two-fluid model is generally able to reproduce the profiles of the mean and turbulent quantities over all stages of the diurnal cycle. As such, the initiation of shallow con- vection and the evolution of the cloud layer are well cap- tured. The robustness of the two-fluid model is further ver- ified using a steady-state test case (BOMEX), in which the cloud properties are also well modelled.