The properties of Southern Ocean (SO) liquid phase non precipitating clouds (hereafter clouds) are examined using shipborne data collected during the Measurements of Aerosols, Radiation and Clouds over the Southern Ocean and the Clouds Aerosols Precipitation Radiation and atmospheric Composition Over the SoutheRN ocean I and II campaigns that took place south of Australia during Autumn 2016 and Summer 2017–2018. Cloud properties are derived using data from W‐band radars, lidars, and microwave radiometers using an optimal estimation algorithm. The SO clouds tended to have larger liquid water paths (LWP, 115 ± 117 g m⁻²), smaller effective radii (r_e, 8.7 ± 3 μm), and higher number concentrations (N_d, 90 ± 107 cm⁻³) than typical values of eastern ocean basin stratocumulus. The clouds demonstrated a tendency for the LWP to increase with N_d presumably due to precipitation suppression up to N_d of approximately 100 cm⁻³ when mean LWP decreased with increasing N_d. Due to higher optical depth, cloud albedos were less susceptible to changes in N_d compared to subtropical stratocumulus. The highest latitude clouds of the datasets, observed along and near the Antarctic coast, presented a distinctly bimodal character. One mode had the properties of marine clouds further north. The other mode occurred in an aerosol environment characterized by high cloud condensation nuclei concentrations and elevated sulfate aerosol without obvious continental aerosol markers. These regions of higher cloud condensation nuclei tended to have higher N_d, smaller r_e and higher LWP suggesting sensitivity of cloud properties to seasonal biogenic aerosol production in the high latitude SO.

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源自CAPRICORN和MARCUS数据的南方海洋云属性

使用在测量南大洋上的气溶胶，辐射和云以及南大洋I上的云气溶胶降水辐射和大气成分的过程中收集的船载数据来检查南大洋（SO）液相非降水云（以下称云）的特性以及在2016年秋季和2017-2018年夏季在澳大利亚南部进行的第二次运动。使用最佳估算算法，使用来自W波段雷达，激光雷达和微波辐射计的数据得出云的属性。SO云倾向于具有较大的液态水路径（LWP，115±117 gm ^-2），较小的有效半径（r _e，8.7±3μm）和较高的数浓度（N _d，90±107 cm ^-3））比东部海盆地层积云的典型值高。当平均LWP随着N _d的增加而降低时，云层显示LWP随N _d的增加而增加的趋势可能是由于降水抑制，直到N _d约为100 cm ^-3。由于较高的光学深度，云的反照率不易受N _d变化的影响与亚热带平流积云相比。沿南极沿海及其附近观测到的数据集的最高纬度云呈现出明显的双峰特征。一种模式具有更北的海洋云的特性。另一种模式发生在以高云凝结核浓度和高水平的硫酸盐气溶胶为特征的气溶胶环境中，而没有明显的大陆气溶胶标记。高云凝结核的这些区域往往具有较高的N _d，较小的r _e和较高的LWP，这表明高纬度SO中云特性对季节性生物气溶胶生产的敏感性。