Aeolian sand transport drives geophysical phenomena, such as bedform evolution and desertification. Creep plays a crucial, yet poorly understood, role in this process. We present a model for aeolian creep, making quantitative predictions for creep fluxes, which we verify experimentally. We discover that the creep transport rate scales like the Shields number to the power 5/2, clearly different from the laws known for saltation. We derive this 5/2 power scaling law from our theory and confirm it with meticulous wind tunnel experiments. We calculate the creep flux and layer thickness in steady state exactly and for the first time study the relaxation of the flux toward saturation, obtaining an analytic expression for the relaxation time. Plain Language Summary The sand transport of granular beds under the action of turbulent wind‐sheared flows is of major importance for the bedforms evolution and desertification processes. Up to now, the saltation transport is well understood and predictable but not the creep transport and relevant scaling laws. In this study, a theory for the aeolian creep transport is developed and verified through wind tunnel experiments. We propose for the first time a scaling law with the Shields number for the creep transport rate. Our novel model allows predictions of the aeolian creep transport rate and shows that it captures the relaxation process in actual creep transport. Such theoretical model provides key tools for the study of aeolian creep but could not previously be studied in such detail. Our study provides a better understanding for the phenomenon that the bed surface itself appeared to be “fluidized” in aeolian sand transport.

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风成蠕变传输：理论与实验

风沙输送驱动地球物理现象，如床型演化和荒漠化。蠕变在这个过程中起着至关重要但知之甚少的作用。我们提出了一个风成蠕变模型，对蠕变通量进行了定量预测，我们通过实验对其进行了验证。我们发现蠕变传输率与盾牌数的 5/2 次幂一样，明显不同于已知的跳跃定律。我们从我们的理论中推导出这个 5/2 幂缩放定律，并通过细致的风洞实验证实了这一点。我们准确计算了稳态蠕变通量和层厚度，并首次研究了通量向饱和的弛豫，获得了弛豫时间的解析表达式。简明语言小结 湍流风切变作用下颗粒层的沙输运对于床型演化和荒漠化过程具有重要意义。到目前为止，跃迁传输已被很好地理解和预测，但蠕变传输和相关的标度定律却不是。在这项研究中，通过风洞实验开发并验证了风成蠕变传输的理论。我们首次提出了一个带有 Shields 数的比例定律，用于蠕变传输速率。我们的新模型可以预测风成蠕变传输速率，并表明它捕获了实际蠕变传输中的松弛过程。这种理论模型为研究风成蠕变提供了关键工具，但以前无法进行如此详细的研究。