Aerodynamic surface stress imposed by the atmospheric surface layer (ASL) drives aeolian sediment transport processes. When the imposed stress exceeds fluid threshold, splashing sand grains release fine (aerosol) particles. This process stops when the imposed stress falls below an impact threshold. Turbulence in the ASL is composed of elongated streaks of relatively high and low streamwise momentum (high‐momentum and low‐momentum regions, HMR and LMR, respectively), and these streaks are aligned with the prevailing winds. Streamwise‐wall‐normal turbulent stress is the concurrent product of fluctuations in streamwise and vertical velocity. These production mechanisms are categorized into quadrants: sweeps, inner interactions, ejections, and outer interactions, where the first two and last two occur within HMRs and LMRs, respectively. Under typical ASL conditions, the time‐averaged shear velocity is bound between 0.3 and 0.5 m/s, demonstrating the importance of fluctuations in mobilizing sand grains via saltation: time‐averaged shear velocity exceeding threshold does not correspond with typical ASL conditions. Given the aforementioned contributions to streamwise‐wall‐normal turbulent stresses from sweeps and ejections, it is self‐evident that under typical conditions only sweeps possess the momentum required to exceed threshold. But, any dust released is trapped by downwelling from aloft; ejections rarely exceed threshold, but they contain the positive vertical velocity needed to entrain. These attributes represent an entrainment paradox. Complementary field data are used to demonstrate the existence of an entrainment paradox. Large eddy simulation has been used to capture space‐time evolution of an idealized ASL and identify mechanistic flow physics central to entrainment.

中文翻译：

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“引诱悖论：滞后盐分和二次运输如何增强风源原料的大气吸收”

大气表层（ASL）施加的空气动力学表面应力推动了风沙沉积物的运输过程。当施加的应力超过流体阈值时，飞溅的沙粒会释放出细小颗粒（气溶胶）。当施加的压力降至冲击阈值以下时，此过程停止。ASL中的湍流由相对较高和较低的水流动量（高动量和低动量区域，分别为HMR和LMR）的细长条纹组成，这些条纹与盛行风对齐。流向壁法向湍流应力是流向和垂直速度波动的同时产物。这些生产机制分为四部分：扫掠，内部相互作用，弹出和外部相互作用，其中前两个和后两个分别发生在HMR和LMR中。在典型的ASL条件下，时间平均剪切速度限制在0.3和0.5 m / s之间，这表明波动通过盐化动员沙粒的重要性：时间平均剪切速度超过阈值并不符合典型的ASL条件。鉴于上述对扫掠和弹射产生的沿流壁法向湍流应力的贡献，不言而喻的是，在典型条件下，仅扫掠物具有超过阈值所需的动量。但是，释放出的所有灰尘都被高空下落所困住了。喷射很少会超过阈值，但它们包含夹带所需的正垂直速度。这些属性代表了一种夹带悖论。补充的现场数据用于证明夹带悖论的存在。