Cold pool fronts as causal links between convective thunderstorms in channel domain

Abstract:

Coldpool are formed under precipitating clouds because the evaporation of raindrops cool the air – thus increasing its density and resulting in density current leading it down and out. It is known that such coldpools can again trigger new convective events, which will produce new coldpools. Here we study the outcome of cloud-resolving RCE simulations over a channel domain. By averaging over the narrow dimension we can simplify the coldpool fronts to lines in a 2D space-time diagram. By this procedure we can reduce the data to a causal graph where each node represent a rain event and the edges represent coldpool fronts. We use this discretization to perform statistics about the relation between connected rain events, and to answer questions about the emergence of extreme events such as the emergence of self-aggregation.