Aircraft Observations of Supercooled Liquid Water and Ice Particle Concentrations in Mixed-phase Stratiform Clouds with Embedded Convection during a Cold Wave over northen and southern China

From November 5 to 8, 2021, a cold wave occurred in China, and a large range of frontal clouds moved from west to east and south, affecting most parts of central and eastern China. There have been few comparative analyses on the microphysical characteristics of the clouds over northern and southern China under the influence of such large-scale weather system. In this paper, the distribution of supercooled liquid water and ice particle concentrations of the northern snowfall cloud in the developing stage and the southern rainfall cloud in the weakening stage are analyzed by using the aircraft measurements combined with radar and precipitation data carried out in Shanxi and Anhui provinces from November 6 to 7. In the early stage of system development, aircraft observations in Shanxi was in the stage of frontal precipitation accompanied by rainfall and snowfall conversion. At this stage, the middle-upper layer is affected by the northwest airflow behind the cold front to form a cold layer, while the lower layer at approximately 3 km was a warm layer affected by the southwest airflow. The corresponding cloud system had high ice particles concentrations of 102 L-1 in the -12~-8℃ layer, while the -6℃~-8℃ layer was dominated by supercooled liquid water, and the maximum water content was 0.42 g m-3. Different from the cloud in Shanxi province, the cloud in Anhui province was in the late stage of precipitation when aircraft measurements were conducted, and the concentrations of ice particles were low. Because of the limited uplift of the lower water vapor, there was still a small amount of unconsumed supercooled liquid water in the -10℃ layer of the cloud, which was discontinuous with the lower cloud in the vertical direction.