资源环境科技发展态势分析平台

Ground-based remote sensing measurements from the Atmospheric Radiation Measurement Program (ARM) West Antarctic Radiation Experiment (AWARE) campaign at the McMurdo station and the ARM North Slope of Alaska (NSA) Utqia & x121;vik site are used to retrieve and analyze single-layer stratiform mixed-phase cloud macrophysical and microphysical properties for these different polar environments. Single-layer stratiform mixed-phase clouds have annual frequencies of occurrence of similar to 14.7% at Utqia & x121;vik and similar to 7.3% at McMurdo, with the highest occurrences in early autumn. Compared to Utqia & x121;vik, stratiform mixed-phase clouds at McMurdo have overall higher and colder cloud-tops, thicker ice layer depth, thinner liquid-dominated layer depth, and smaller liquid water path. These properties show clear seasonal variations. Supercooled liquid fraction at McMurdo is greater than at Utqia & x121;vik because, at a given temperature, McMurdo clouds have comparable liquid water paths but smaller ice water paths. Analyses of retrieved cloud microphysical properties show that compared to Utqia & x121;vik, stratiform mixed-phase clouds at McMurdo have greater liquid droplet number concentration, smaller layer-mean effective radius, and smaller ice water content and ice number concentration at a given cloud-top temperature. These relationships may be related to different aerosol loading and chemical composition, and environment dynamics. Results presented in this study can be used as observational constraints for model representations of stratiform mixed-phase clouds.