Morphological Regimes of Rotating Moist Convection

TL;DR

This study explores how rotation influences moist convection, revealing three distinct flow regimes, including a novel funnel regime, and analyzing their effects on energy transport and flow structure.

Contribution

It introduces a new funnel regime in rotating moist convection and provides detailed numerical analysis of its properties and scaling behaviors.

Findings

Identification of three morphological regimes: cellular, plume, and funnel.

The funnel regime enhances moist static energy transport without increasing flow velocity.

Rotational effects significantly alter convection structures and energy fluxes.

Abstract

Moist convection is a physical process where the latent heat released by condensation acts as a buoyancy source that can enhance or even trigger an overturning convective instability. Since the saturation temperature often decreases with height, condensation releases latent heat preferentially in regions of upflow. Due to this inhomogeneous heat source, moist convection may be more sensitive to changes in flow morphology, such as those induced by rotation, than dry Rayleigh-B\'enard convection. In order to study the effects of rotation on flows driven by latent heat release, we present a suite of numerical simulations that solve the Rainy-B\'enard equations (Vallis et al. 2019). We identify three morphological regimes: a cellular regime and a plume regime broadly analogous to those found in rotating Rayleigh B\'enard convection, and a novel funnel regime that lacks a clear analog within the regimes exhibited by dry convection. We measure energy fluxes through the system and report rotational scalings of the Reynolds and moist Nusselt numbers. We find that moist static energy transport, as measured by a moist Nusselt number, is significantly enhanced in the funnel regime without a corresponding enhancement in Reynolds number, indicating that this funnel regime produces structures with more favorable correlations between the temperature and vertical velocity.