A model study of internal waves.
Authors
Weigand, James Gary
Subjects
Advisors
Date of Issue
1962-08
Date
Publisher
University of Washington
Language
en_US
Abstract
Experiments on the generation of internal waves by low amplitude
surface wave traveling over a continental shelf were carried out in a
U-shaped wave channel 10. U m long, O.k m wide and up to O.U m deep. Long
surface waves were generated at one end of this channel, and various model
continental shelves were placed at the other end. ' The shelves were either
of uniform depth or of constant slope, and their height above the bottom
and width could be varied over wide ranges. An approximate two -layer system
was achieved by means of a fresh water layer introduced over a saline layer.
The salinity profile was determined by titration of microsamples drawn
from a series of depths. Amplitude and period of surface waves, depth,
width, and shape of the shelf, density distribution and total depth were
varied independently. Quantitative data on the waves were obtained from
both moving and still photographs of dye on the interface between the two
layers. The experiments have demonstrated the effectiveness of this
mechanism in generating large amplitude internal waves. Friction was
important in many of the cases studied, and often caused the internal
waves over the shelf to be progressive waves traveling toward the shore,
instead of the standing waves predicted by theory. Progressive waves were
always found to travel seaward from the continental slope region. The
amplitude of the internal waves was found to be in general agreement with
the theory of Rattray (i960), when friction was not important in the model.
In many cases active mixing took place in the shelf region, and in some
cases density currents were formed.
Type
Thesis
Description
Series/Report No
Department
Oceanography