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Circling in on Convective Self-Aggregation.

ABSTRACT: In radiative-convective equilibrium simulations, convective self-aggregation (CSA) is the spontaneous organization into segregated cloudy and cloud-free regions. Evidence exists for how CSA is stabilized, but how it arises favorably on large domains is not settled. Using large-eddy simulations, we link the spatial organization emerging from the interaction of cold pools (CPs) to CSA. We systematically weaken simulated rain evaporation to reduce maximal CP radii, Rmax , and find reducing Rmax causes CSA to occur earlier. We further identify a typical rain cell generation time and a minimum radius, Rmin , around a given rain cell, within which the formation of subsequent rain cells is suppressed. Incorporating Rmin and Rmax , we propose a toy model that captures how CSA arises earlier on large domains: when two CPs of radii ri,rj∈[Rmin,Rmax] collide, they form a new convective event. These findings imply that interactions between CPs may explain the initial stages of CSA.

SUBMITTER: Nissen SB

PROVIDER: S-EPMC9285845 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Circling in on Convective Self-Aggregation.

Nissen Silas Boye SB Haerter Jan O JO

Journal of geophysical research. Atmospheres : JGR 20211011 20

In radiative-convective equilibrium simulations, convective self-aggregation (CSA) is the spontaneous organization into segregated cloudy and cloud-free regions. Evidence exists for how CSA is stabilized, but how it arises favorably on large domains is not settled. Using large-eddy simulations, we link the spatial organization emerging from the interaction of cold pools (CPs) to CSA. We systematically weaken simulated rain evaporation to reduce maximal CP radii, R max , and find reducing R max ...[more]

PMID: 35864905

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