Data from: Observations of the internal wave to turbulence cascade

Shear spectral energy density (shear spectra) is measured across three
decades in vertical wavenumber using a Wirewalker profiler equipped with a
microstructure instrument and a pulse-coherent Doppler sonar. We identify
the features of the canonical ocean vertical shear spectrum, including an
internal wave band, an intermediate saturation band whose spectral level
is independent of turbulent dissipation, and a three-dimensional
turbulence band. The internal wave band and saturation band of the
spectrum scale as $\Phi_{IW}\sim\varepsilon\frac{1}{2}N1f{- \frac{1}{2}}$
and $\Phi_{sat}\sim N2 k_z^{-1}$ respectively. These scalings hold despite
the deployment location at the head of a La Jolla canyon, a deep canyon
incising the shelf off La Jolla, California, where weakly non-linear
wave-wave interaction is not the primary physical process driving the
forward energy cascade. In La Jolla Canyon, high-amplitude, tidally driven
internal waves generate significant strain, resulting in turbulent events
that cover a majority of the water column. During these events, we observe
shear spectra with energy above the saturation level, which we interpret
as a sign of the wave-turbulence transition. Finestructure
parameterizations developed to predict mixing from shear spectra in the
open ocean thermocline continue to predict average mixing well. The
success of finestructure parameterizations implies a rate of downscale
energy transfer consistent with the rate predicted from weakly non- linear
wave-wave interactions, and suggests that the theoretical framework of the
canonical shear spectrum can be used to make useful predictions in
shallow, high-energy environments.