Kurt L. Polzin

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Observations of internal wave velocity fluctuations show that enhanced turbulent mixing over rough topography in the Southern Ocean is remarkably intense and widespread. Mixing rates exceeding background values by a factor of 10 to 1000 are common above complex bathymetry over a distance of 2000 to 3000 kilometers at depths greater than 500 to 1000 meters.(More)
Diapycnal mixing plays a significant role in the ocean's circulation and uptake of heat and carbon dioxide, but has not been quantified in salt finger-driven thermohaline staircases. We recently performed a tracer release experiment in the western tropical Atlantic staircase at approximately 400 m depth. The observed dispersion implies an effective(More)
The high-frequency limit of the Garrett and Munk spectrum of internal waves in the ocean and the observed deviations from it are shown to form a pattern consistent with the predictions of wave turbulence theory. In particular, the high-frequency limit of the Garrett and Munk spectrum constitutes an exact steady-state solution of the corresponding kinetic(More)
Motivated by the recent interest in ocean energetics, the widespread use of horizontal eddy viscosity in models, and the promise of high horizontal resolution data from the planned wide-swath satellite altimeter, this paper explores the impacts of horizontal eddy viscosity and horizontal grid resolution on geostrophic turbulence, with a particular focus on(More)
This paper examines two internal lee wave closures that have been used together with ocean models to predict the time-averaged global energy conversion rate into lee waves and dissipation rate associated with lee waves and topographic blocking: the Garner (2005) scheme and the Bell (1975) theory. The closure predictions in two Southern Ocean regions where(More)
We present a theory predicting the high-frequency-high-wavenumber part of the spectral energy density of internal waves in the ocean. The theory is based on the wave turbulence formalism applied to a natural Hamiltonian description for the internal wave field. We show that stationary energy spectra form a family of statistically steady state scale invariant(More)
Various approaches have been developed over the last four decades to characterize the magnitude of nonlinear interaction between triads of internal waves in stratified oceanographic flows. The present manuscript compares some of these approaches and demonstrates that, in the limit of long internal waves in hydrostatic balance and in the absence of rotation,(More)
Steady scale-invariant solutions of a kinetic equation describing the statistics of oceanic internal gravity waves based on wave turbulence theory are investigated. It is shown in the nonrotating scale-invariant limit that the collision integral in the kinetic equation diverges for almost all spectral power-law exponents. These divergences come from(More)
Various approaches have been developed over the last four decades to characterize the magnitude of nonlinear interactions between triads of internal waves in stratified oceanic flows. The present manuscript compares some of these approaches and their predictions for internal wave nonlinearity parameter and Boltzman rate. We demonstrate that, for resonant(More)
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