Fog has a wide range of impacts that can include transportation disruptions and climate effects. Despite being a common phenomenon, models struggle to incorporate fog microphysical properties which can affect the visibility, formation and dissipation of fog. Results are presented from a fog microphysics study conducted in June and July of 2016 near Halifax, on the eastern coast of Canada, where droplet and aerosol size distributions were measured, as well as fog droplet residuals using a ground-based counterflow virtual impactor. In the ten distinct events that were analyzed, fog never formed when the dew-point temperature was lower than the sea-surface temperature, suggesting that advection fog was primarily observed. During fog events, the concentration of particles larger than 500 nm in diameter was observed to decrease up to 90%, suggesting that nucleation scavenging was an important loss process during fog. Maximum droplet concentration was correlated (r = 0.61) to the total pre-fog aerosol concentration, despite a large (423 nm) estimated activation diameter. From our measurements, the peak supersaturation (SS) was estimated to range from 0.015–0.046%, including uncertainties due to chemical composition, which is lower than previous estimates for continental fog, including mountain sites, and would be consistent with advection fog as well as the presence of sea salt aerosol. Using basic assumptions, we estimate that for each added aerosol per cm³ in the air mass, the maximum fog droplet concentration increases by 0.011 per cm³ and the fog albedo increases by (0.55–3.8) × 10⁻⁴. This in-situ dataset will help evaluate models to ultimately improve fog forecasts for coastal areas and further our understanding of aerosol-cloud interactions.

雾具有广泛的影响，包括交通中断和气候影响。尽管是一种普遍现象，但模型很难结合雾的微物理特性，这些特性会影响雾的能见度、形成和消散。结果来自于 2016 年 6 月和 7 月在加拿大东海岸哈利法克斯附近进行的雾微物理学研究，其中测量了液滴和气溶胶尺寸分布，以及使用地面逆流虚拟撞击器测量雾滴残留。在分析的十个不同事件中，当露点温度低于海面温度时，雾从未形成，这表明主要观察到平流雾。在雾事件期间，观察到直径大于 500 nm 的颗粒浓度降低了 90%，表明成核清除是雾期间的重要损失过程。最大液滴浓度相关（r  = 0.61) 到雾前总气溶胶浓度，尽管估计的激活直径很大 (423 nm)。根据我们的测量，峰值过饱和度 (SS) 估计在 0.015-0.046% 之间，包括由于化学成分引起的不确定性，这低于先前对大陆雾（包括山区）的估计，并且也与平流雾一致由于海盐气溶胶的存在。使用基本假设，我们估计对于空气质量中每 cm ³增加的气溶胶，最大雾滴浓度每 cm ³增加 0.011 ，雾反照率增加 (0.55–3.8) × 10 ^-4. 该原位数据集将有助于评估模型，最终改善沿海地区的雾预测，并进一步了解气溶胶-云相互作用。