Multiscale Variability of Deep Convection In Realation to Large-Scale Circulation in TOGA COARE

Abstract

Deep convection over the Indo–Pacific oceanic warm pool in the Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment (TOGA COARE) occurred in cloud clusters, which grouped together in regions favoring their occurrence. These large groups of cloud clusters produced large-scale regions of satellite-observed cold cloud-top temperature. This paper investigates the manner in which the cloud clusters were organized on time and space scales ranging from the seasonal mean pattern over the whole warm-pool region to the scale of individual cloud clusters and their relationship to the large-scale circulation and sea surface temperature (SST). The dominant convective variability was associated with the intraseasonal oscillation (ISO). A large eastward propagating ensemble of cloud clusters marked the ISO's progress. The meridional structure of the ISO was strongly affected by the seasonal cycle with a southward shift from the Northern Hemisphere in October–November to the Southern Hem... Abstract Deep convection over the Indo–Pacific oceanic warm pool in the Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment (TOGA COARE) occurred in cloud clusters, which grouped together in regions favoring their occurrence. These large groups of cloud clusters produced large-scale regions of satellite-observed cold cloud-top temperature. This paper investigates the manner in which the cloud clusters were organized on time and space scales ranging from the seasonal mean pattern over the whole warm-pool region to the scale of individual cloud clusters and their relationship to the large-scale circulation and sea surface temperature (SST). The dominant convective variability was associated with the intraseasonal oscillation (ISO). A large eastward propagating ensemble of cloud clusters marked the ISO's progress. The meridional structure of the ISO was strongly affected by the seasonal cycle with a southward shift from the Northern Hemisphere in October–November to the Southern Hem...