Observational evidence for the non-suppression effect of atmospheric
chemical modification on the ice nucleation activity of East Asian dust
Abstract
Mineral dust alters cloud microphysical properties by acting as
ice-nucleating particles (INPs). The effects of anthropogenic pollution
aging on the ice nucleation activity (INA) of mineral dust are still
controversial. Such effects were investigated by verifying the chemical
aging of airborne size-resolved Asian dust particles via particle
chemistry and morphology analyses and comparing the immersion mode INP
properties of aged and normal Asian dust. The INP concentrations and ice
nucleation active site densities of chemically aged supermicron dust
particles (1.0-10.0 μm) were nearly equal to or slightly higher than
those of normal Asian dust, which were 0.70-2.45 times and 0.64-4.34
times at -18 ℃, respectively. These results reveal that anthropogenic
pollution does not notably change the INP concentrations and does not
impair the INA of Asian dust. Our work provides direct observational
evidence and clarifies the non-suppression effect of anthropogenic
pollution on the INA of airborne East Asian dust.