Satellite remote sensing of dust aerosol indirect effects on cloud formation over Eastern Asia

Abstract

The dust aerosol indirect effect of the first kind on ice and liquid water cloud formation has been investigated using available MODIS cloud and aerosol products on the basis of correlation analysis. The variability in the correlation between cloud parameters, including optical depth, effective particle size, cloud water path and cloud particle number concentration, and aerosol variables, including optical depth and number concentration, over Eastern Asia has been studied. Three MODIS scenes that contain a significant presence of local and transported dust and clouds have been selected for comprehensive analysis. For all cases studied, we demonstrate that there is a negative trend regarding the correlation between cloud particle size and aerosol optical depth, which is statistically significant. These results represent a strong evidence of dust and cloud interactions that are consistent with the hypothesis of the Twomey effect for clouds.