Internal gravity waves, the subsurface analogue of the familiar
surface gravity waves that break on beaches, are ubiquitous in
the ocean. Because of their strong vertical and horizontal currents,
and the turbulent mixing caused by their breaking, they affect a
panoply of ocean processes, such as the supply of nutrients...
Sea surface temperature (SST) is a critical control on the atmosphere(1), and numerical models of atmosphere-ocean circulation emphasize its accurate prediction. Yet many models demonstrate large, systematic biases in simulated SST in the equatorial 'cold tongues' (expansive regions of net heat uptake from the atmosphere) of the Atlantic(2) and Pacific(3)...
As currents flow over rough topography, the pressure difference between the up-and downstream sides results in form drag-a force that opposes the flow. Measuring form drag is valuable because it can be used to estimate the loss of energy from currents as they interact with topography. An array of bottom...
Packets of nonlinear internal waves (NLIWs) in a small area of the Mid-Atlantic Bight were 10 times more energetic during a local neap tide than during the preceding spring tide. This counterintuitive result cannot be explained if the waves are generated near the shelf break by the local barotropic tide...
Turbulence controls the composition of river plumes through mixing and alters the plume's trajectory by diffusing its momentum. While believed to play a crucial role in decelerating river-source waters, the turbulence stress in a near-field river plume has not previously been observationally quantified. In this study, finely resolved density, velocity,...
A procedure for estimating thermal variance dissipation rate χ[subscript]T by scaling the inertial-convective subrange of temperature gradient spectra from thermistor measurements on a Tropical Atmosphere Ocean (TAO) equatorial mooring, maintained by NOAA’s National Data Buoy Center, is demonstrated. The inertial-convective subrange of wavenumbers/frequencies is contaminated by the vertical motion induced...
A reexamination of turbulence dissipation measurements from the equatorial Pacific shows that the turbulence diffusivities are not a simple function of the gradient Richardson number. A widely used mixing scheme, the K-profile parameterization, overpredicts the turbulent vertical heat flux by roughly a factor of 4 in the stably stratified region...
The initial composition of a river plume depends on the cumulative turbulent
entrainment within the estuary and how this dilutes the supplied freshwater. Here we
examine the relative roles of turbulence and freshwater input using observations from the
Columbia River estuary and plume during two periods with contrasting river flow....
Varied observations over Oregon’s continental shelf illustrate the
beauty and complexity of geophysical flows in coastal waters. Rapid, creative, and
sometimes fortuitous sampling from ships and moorings has allowed detailed looks
at boundary layer processes, internal waves (some extremely nonlinear), and coastal
currents, including how they interact. These processes drive...
Horizontal tow measurements of internal waves are rare and have been largely supplanted in recent
decades by vertical profile measurements. Here, estimates of isotherm displacements and turbulence dissipation
rate from a towed vehicle deployed near Hawaii are presented. The displacement data are interpreted
in terms of horizontal wavenumber spectra of...