Density stratification due to temperature or salinity variations greatly influences the flow around and the sedimentation of objects such as particles, drops, bubbles, and small organisms in the atmosphere, oceans, and lakes. Density stratification hampers the vertical flow and substantially affects the sedimentation of an isolated object, the hydrodynamic interactions between a pair of objects, and the collective behavior of suspensions in various ways, depending on the relative magnitude of stratification, inertia (advection), and viscous (diffusion) effects. This review discusses these effects and their hydrodynamic mechanisms in some commonly observed fluid–particle transport phenomena in oceans and the atmosphere. Physical understanding of these mechanisms can help us better model these phenomena and, hence, predict their geophysical, engineering, ecological, and environmental implications.

中文翻译：

---

分层流体中的运动


由于温度或盐度变化引起的密度分层会极大地影响大气、海洋和湖泊中颗粒、水滴、气泡和小生物等物体的流动和沉积。密度分层阻碍了垂直流动，并以各种方式严重影响孤立物体的沉积、一对物体之间的流体动力学相互作用以及悬浮物的集体行为，具体取决于分层的相对大小、惯性（平流）和粘性（扩散）效应。本文讨论了海洋和大气中一些常见的流体-粒子传输现象中的这些效应及其流体动力学机制。对这些机制的物理理解可以帮助我们更好地模拟这些现象，从而预测它们的地球物理、工程、生态和环境影响。