Revisiting the parameterization of ice nucleation of dust particles under mixed-phase cloud conditions from laboratory measurements

Dust aerosol plays a key role in cloud formation and evolution due to its high atmospheric abundance and efficient ice nucleation ability (INA). A generalized parameterization of dust-induced ice formation in climate models remains challenging, because dust INA varies substantially with mineral composition, aerosol generation methods, and atmospheric aging processes. In this study, we revisited the INA of dust particles under mixed-phase cloud conditions (MPC, −38 < T < 0 °C) compiled from previous laboratory studies. Our results indicate that INA of dust particles with different mineral compositions exhibit variability spanning up to 6 orders of magnitude in INA at −38 < T < −2 °C. When accounting for mineralogical differences, aerosol generation methods whether particles are dry-dispersed or wet-suspended also contribute to the reported variability. This sample preparation difference likely arises from variations in water-particle interactions time scales that are longer in the suspension than the aerosol measurements. Aging generally reduces dust INA, with chemical reactions inducing the strongest reduction, followed by thermal treatments and water/aqueous aging. Based on these findings, we developed a suite of n s -based parameterizations to represent INA of dust particles with mixed and specific mineral composition. We also proposed parameterizations based on D e (spherical equivalent particle diameter within a droplet), which predict droplet freezing across the full MPC temperature range using a single expression. These empirical parameterizations capture the general INA trends of dust particles and are expected to improve the accuracy of predictions of dust-induced cloud formation in climate models.