Lawrence Berkeley National Laboratory

The atmosphere can self-organize into long-lasting large-scale overturning circulations over an ocean surface with uniform temperature. This phenomenon is referred to as convective self-aggregation and has been argued to be important for tropical weather and climate systems. Here we present a boundary layer centric framework based on the available potential energy budget of convective self-aggregation. We show that boundary layer diabatic processes dominate the available potential energy production and are, therefore, essential to convective self-aggregation. We further show that the enhanced virtual effect of water vapor can lead to convective self-aggregation.