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R. Beardsley

Publications and source records attributed to R. Beardsley.

2 recordsLinked to original sources

Coastal ocean dynamics

The main objective of the Coastal Ocean Dynamics Experiment (CODE) is to observe and describe the response of continental shelf waters to strong atmospheric forcing in a relatively simple geomorphological setting. In order to achieve this goal, CODE has been designed (1) to define the different space and time scales of the physical parameters important to the shelf flow field and (2) to identify and describe the essential kinematical and dynamical processes governing wind‐driven circulation on the continental shelf. A variety of models exist for the wind‐forced response of continental shelf waters. The salient differences among these models lies in the assumed balances between terms in the governing equations. For example, Gill and Schumann [1974] in a barotropic model assume a geostrophic cross‐shelf momentum balance but include the time‐dependent and surface and bottom stress terms in the along‐shelf momentum balance. Csanady [1978] in his arrested topographic wave model involving bottom friction assumes a quasisteady alongshelf response neglecting advective terms and retaining the geostrophic cross‐shelf balance. Various shelf wave models assume inviscid dynamics and other models assume a simple balance between surface and bottom stress in shallow water. To test the different assumptions behind these models, all terms in the governing equations need to be accurately estimated.

California

On the interpretation of energy and energy fluxes of nonlinear internal waves: An example from Massachusetts Bay

A self-consistent formalism to estimate baroclinic energy densities and fluxes resulting from the propagation of internal waves of arbitrary amplitude is derived using the concept of available potential energy. The method can be applied to numerical, laboratory or field data. The total energy flux is shown to be the sum of the linear energy flux ??? u??? p??? dz (primes denote baroclinic quantities), plus contributions from the non-hydrostatic pressure anomaly and the self-advection of kinetic and available potential energy. Using highly resolved observations in Massachusetts Bay, it is shown that due to the presence of nonlinear internal waves periodically propagating in the area, ??? u??? p??? dz accounts for only half of the total flux. The same data show that equipartition of available potential and kinetic energy can be violated, especially when the nonlinear waves begin to interact with the bottom. ?? 2006 Cambridge University Press.

Massachusetts Bay