The microphysical properties and processes in in-flight icing: A case study

Supercooled liquid water (SLW) serves as a critical medium for cloud seeding in weather modification operations, yet it presents a paradoxical threat to aviation safety by posing the risk of in-flight icing. This study investigates SLW conditions in the Sichuan Basin during winter, comparing them with those in North America using in situ aircraft measurement data from two in-flight icing events encountered during weather modification field experiments. The Weather Research and Forecasting (WRF) model is employed to evaluate its capability in predicting macro- and micro-environmental conditions conducive to icing weather, with a particular focus on hydrometeor properties and microphysical processes that significantly influence the formation and depletion of SLW. Distinct mechanisms are observed across different cloud systems, underscoring the complexity of these processes. These findings underscore the necessity for further investigation into microphysical processes and their dependence on both macro- and micro-environmental conditions to improve the prediction and understanding of SLW. • Two in-flight icing events experienced by an aircraft is analyzed. • Icing environment in the Sichuan Basin are compared with those in North America. • Numerical model simulates three successive cloud systems containing abundant SLW. • Different microphysical processes contributing to the formation and depletion of SLW varies across the cloud systems.