Revealing the Microphysical Distribution Characteristics of Arctic Mixed‐Phase Clouds

Abstract As a typical cloud type in the Arctic, the microphysical characteristics of Arctic stratiform mixed‐phase clouds (MPCs) are essential for understanding interactions among Arctic clouds, aerosols, and radiation. This study uses 1‐year of shipborne observations from the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition in the Arctic Ocean. It summarizes the typical distribution of microphysical parameters in Arctic MPCs and investigates how cloud‐top droplet microphysical parameters and environmental factors influence ice crystal formation and growth. The results show that Arctic stratiform MPCs exhibit a vertical structure characterized by a liquid phase at the top, a mixed phase in the middle, and an ice phase at the bottom. Ice crystals mainly originate from the liquid‐phase region near the cloud top and grow as they descend through the mixed‐phase layer. Higher liquid water content at the cloud top enhances both riming and depositional growth of ice crystals in the mixed‐phase layer. Small droplets are more readily converted into ice crystals, whereas large droplets favor ice crystal growth to larger sizes. Ice crystal concentration is exponentially negatively correlated with cloud‐top temperature, and ice crystal size reaches its maximum near −15°C due to the combined effects of depositional growth and aggregation. Additionally, significant radiative cooling occurs at the top of MPCs, stimulating turbulence and strong vertical mixing within the cloud, thereby facilitating the formation and maintenance of MPCs.