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Laboratory observations are presented showing the structure and dynamics of the turbulent bottom boundary layer beneath nonlinear internal waves (NLIWs) of depression shoaling upon sloping topography. The adverse pressure gradient beneath the shoaling waves causes the rear face to steepen, flow separation to occur, and wave‐induced near‐bottom vortices to suspend bed material. The resuspension is directly attributed to the near‐bed viscous stress and to near‐bed patches of elevated positive Reynolds stress generated by the vortical structures. These results are consistent with published field observations of resuspension events beneath shoaling NLIWs. Elevated near‐bed viscous stresses are found throughout the domain at locations that are not correlated to the resuspension events. Near‐bed viscous stress is thus required for incipient sediment motion but is not necessarily a precursor for …