We use an idealized cloud resolving model (CRM) utilizing the weak temperature gradient (WTG) approximation, which effectively acts as a parameterization of the effects of the large-scale environment on the local environment. We represent the large-scale environment by imposing steady state radiative convective equilibrium (RCE) temperature and moisture profiles---at respective SSTs---in WTG simulations. WTG simulations exhibit multiple equilibria in precipitation for a range of imposed wind speeds---for the same boundary conditions, moist and dry initialized simulations have either a precipitating or a non-precipitating steady state. We assume a hypothesised analogy between the precipitating and non-precipitating equilibria in WTG simulations to precipitating and non-precipitating regions in convective organisation. Understanding how multiple equilibria in precipitation in WTG simulations depend on SST can lead to better understanding of convective organization in a changing climate.
We find that there are two distinct effects of SST changes on WTG multiple equilibria simulations: effects of changes in the reference environment and effects of surface fluxes as a result of changing wind speeds. First, increasing SSTs produce warmer and moister RCE reference environments. Warmer SSTs exhibit multiple equilibria over a smaller range of wind speeds compared to cooler SSTs. This may suggest that warmer climates favor unorganized convection. Second, the transition time from a dry to a precipitating equilibrium occurs earlier with stronger wind speeds. However, this effect is not SST dependent. Together these results suggest that there is a distinct difference between thermodynamic and dynamics effects of SST changes in WTG simulations, and, by inference, the real atmosphere.