Measurements of Saharan Dust in Convective Clouds over the Tropical Eastern Atlantic Ocean*

Abstract

Abstract Mineral dust particles have been shown to act as cloud condensation nuclei, and they are known to interact with developing tropical storms over the Atlantic downwind of the Sahara. Once present within liquid droplets, they have the potential to act as freezing ice nuclei and further affect the microphysics, dynamics, and evolution of tropical storms. However, few measurements of mineral dust particles in tropical convective clouds exist. This study indicates that about one-third of droplets sampled in small convective clouds in the tropical eastern Atlantic contained dust particles, and dust was the dominant residual particle type sampled in ice crystals from anvil outflow. However, estimated number and mass concentrations of dust in anvil ice were small compared to the amount of dust available within the Saharan air layer itself.