Convective coherent structures shape the atmospheric boundary layer over the lifecycle of marine cold-air outbreaks (CAOs). Aircraft measurements have been used to characterize such structures in past CAOs. Yet, aircraft case studies are limited to snapshots of a few hours and do not capture how coherent structures, and the associated boundary-layer characteristics, change over the CAO time scale, which can be on the order of several days. We present a novel ship-based approach to determine the evolution of the coherent-structure characteristics, based on profiling lidar observations. Over the lifecycle of a multi-day CAO we show how these structures interact with boundary-layer characteristics, simultaneously obtained by a multi-sensor set-up. Observations are taken during the Iceland Greenland Seas Project’s wintertime cruise in February and March 2018. For the evaluated CAO event, we successfully identify cellular coherent structures of varying size in the order of 4 \(\times \) 10\(^2\) m to 10\(^4\) m and velocity amplitudes of up to 0.5 m \(\hbox {s}^{-1}\) in the vertical and 1 m \(\hbox {s}^{-1}\) in the horizontal. The structures’ characteristics are sensitive to the near-surface stability and the Richardson number. We observe the largest coherent structures most frequently for conditions when turbulence generation is weakly buoyancy dominated. Structures of increasing size contribute efficiently to the overturning of the boundary layer and are linked to the growth of the convective boundary-layer depth. The new approach provides robust statistics for organized convection, which would be easy to extend by additional observations during convective events from vessels of opportunity operating in relevant areas.

对流相干结构在海洋冷空气爆发 (CAO) 的生命周期中塑造了大气边界层。在过去的 CAO 中，飞机测量已被用于表征此类结构。然而，飞机案例研究仅限于几个小时的快照，并没有捕捉到连贯结构和相关的边界层特征在 CAO 时间尺度上的变化，可能在几天左右。我们提出了一种新的基于船的方法来确定相干结构特征的演变，基于剖面激光雷达观测。在多天 CAO 的生命周期中，我们展示了这些结构如何与边界层特征相互作用，同时通过多传感器设置获得。 \(\times \)  10 \(^2\)  m 到 10 \(^4\)  m 和速度幅度高达 0.5 m  \(\hbox {s}^{-1}\)在垂直和 1 m  \(\hbox {s}^{-1}\)在水平。结构特征对近地表稳定性和理查森数敏感。当湍流产生以弱浮力为主时，我们最常观察到最大的相干结构。尺寸增加的结构有效地促进了边界层的翻转，并与对流边界层深度的增长有关。新方法为有组织的对流提供了可靠的统计数据，这很容易通过在相关区域运行的机会船只的对流事件期间的额外观察来扩展。