Comparison of dust CCN, GCCN and IN effects on the Development of a Mesoscale Convective System over North Africa

Dust aerosols are widely known to be effective ice nuclei (IN) owing to their nucleation efficiency. Dust aerosols can also serve as cloud condensation nuclei (CCN) and giant CCN depending on its physical and chemical properties. To investigate the impacts of different dust microphysical processes on cloud structure and storm development, we use the WRF-Dust model to conduct sensitivity experiments, which differ only in whether or not they simulate dust-CCN, dust-GCCN and/or dust-IN effects. An MCS that developed over North Africa during 4-6 July 2010 was selected for this study because (1) it developed near a moderate dust plume, and (2) it showed clear anvil cloud extent when it reached the mature stage. Our preliminary comparison among different experiments shows that cloud structure is better predicted in the experiments that include both dust-CCN and dust-IN effects. More comparison and analysis for the impacts of different dust microphysical processes on the MCS development and cold pool intensity change will be presented.