Cloud Microphysical Characteristics in the Northeast China Cold Vortex Derived from Satellite Measurements

The Northeast China Cold Vortex (NCCV), a typical synoptic-scale system in Northeast China, North China, and the Jianghuai region, frequently triggers thunderstorms, strong winds, and heavy precipitation, making it significant for meteorological monitoring and operational forecasting. However, the cloud microphysical properties of NCCV-associated cloud systems remain poorly characterized, as long-term cloud microphysical observations are limited. This study utilizes cloud products from the Moderate Resolution Imaging Spectroradiometer (MODIS) to analyze cloud-type frequencies and four key cloud microphysical properties under NCCV conditions: liquid effective radius (Re_liq), ice effective radius (Re_ice), liquid water path (LWP), and ice water path (IWP). Nearly identical cloud-type compositions are found for the two groups, NCCV and non-NCCV samples with similar cloud fractions on the regional scale, which are dominated by stratocumulus (Sc), altostratus (As), cumulus (Cu), and stratus (St), with Sc accounting for above 40% of total cloud occurrence. Yet microphysical properties differ markedly between these two groups. LWP shows the most contrast and it is evidently larger in NCCV than in non-NCCV cloud systems. As for the spatial structure of cloud microphysics in the NCCV domain, it is found that Sc, As, St, and nimbostratus (Ns) constitute the primary background, and Sc remains the dominant cloud type in almost all spatial sectors. LWP and IWP tend to have stronger spatial heterogeneity than Re_liq and Re_ice. LWP gets notably larger in the northern to northwestern sectors, whereas IWP shows much higher variations in both radial and azimuthal dimensions. These results reveal the statistical microphysical characteristics of cloud systems associated with NCCV from the perspective of satellite observations, providing a reference for a deeper understanding of their unique cloud and precipitation physical processes.