A Stochastic Parameterization of Organized Tropical Convection Using Cellular Automata for Global Forecasts in NOAA's Unified Forecast System

In the atmosphere, convection can organize from smaller scale updrafts into more coherent structures on various scales. bulk-plume cumulus parameterizations, this type of organization has to be represented in terms how resolved flow would “feel” if were present subgrid. This subgrid acts as building blocks for larger tropical convective known modulate local and remote weather. work a parameterization (and cross-grid) scheme is proposed using stochastic, self-organizing, properties cellular automata (CA). We investigate effects CA which interact with three different components that activity: entrainment, triggering, closure. The impacts revised schemes are studied model's ability convectively coupled equatorial waves (CCEWs). differing adopting stochastic scheme, compared widely used Stochastically Perturbed Physics Tendency (SPPT) also assessed. Results show precipitation spatially temporally organized, there systematic shift wave phase speed not seen SPPT. Previous studies have noted linear relationship between Gross Moist Stability (GMS) Kelvin speed. Analysis GMS study shows an increase tied large-scale precipitation.