عنوان

A study of ocean internal waves using space shuttle data

Number

TLpq304345550

.Language of Text, Soundtrack etc

انگلیسی

Title Proper

A study of ocean internal waves using space shuttle data

General Material Designation

[Thesis]

First Statement of Responsibility

Z. Wang

Subsequent Statement of Responsibility

V. V. Klemas

Name of Publisher, Distributor, etc.

University of Delaware

Date of Publication, Distribution, etc.

1997

Specific Material Designation and Extent of Item

163

Dissertation or thesis details and type of degree

Ph.D.

Body granting the degree

University of Delaware

Text preceding or following the note

1997

Text of Note

The primary objectives of this study were to better understand the remote sensing mechanisms of ocean internal waves, and to apply space shuttle data to studies of upper ocean processes. Space shuttle photographs and Spaceborne Imaging Radar-C images of the Arabian Sea area were collected and used for this study. Statistical analysis of spatial structures of internal waves yielded distribution histograms of soliton number per packet and soliton wavelengths. The histogram of the soliton number per packet peaked at around 4, and a larger number of up to 18 in a packet was also observed. The soliton wavelength ranged from 0.1 to 2.8 km with a mean value of 0.9 0.5 km near the Somali coast, and from 0.1 to 1.2 km with a mean value of 0.4 0.2 km in the coastal ocean near Bombay. The distribution curve of soliton wavelengths resembles a Gaussian distribution. With decreasing of water depth, the peak wavelength tends to decrease and appears to skew towards shorter wavelengths. For a variable bottom topography, the distribution approaches a Rayleigh distribution. With a finite-water-depth model, dynamic parameters of internal waves near the Somali coast were derived, giving a maximum amplitude of 18 m, characteristic phase speed of 0.87 ms and period of 29 min. The dynamic analysis demonstrated that the tides were the dominant generation forces for the solitons. The internal-wave packets propagating toward offshore and along the shoreline appeared to be generated by the reflected and deflected tidal waves at the continental shelf, respectively. The strange shapes and appearances of solitary patterns were confirmed as due to the influence of the surface circulation and the bottom topography on internal-wave propagation. An optical model for the remote sensing of ocean internal waves was developed. The directional dependence of the reflected light from the surface modulated by internal waves is the mechanism which causes darker or lighter bands on the soliton photograph. Variations of ocean upwelling light due to the inhomogeneous particle concentration caused by internal-wave motion may give darker stripes on the photograph. This model was used to examine the solitary features in the photographs taken at different positions during the flight of the shuttle. The lighter or darker band features are believed to be mainly due to the surface reflection of solar radiation in different observation directions. The darker stripe seen in front of a lighter band in a certain direction seemed to be caused by both contributions.

Applied sciences

Arabian Sea

Earth sciences

Ocean engineering

Oceanography

Remote sensing

V. V. Klemas

Z. Wang

Electronic name

p

[Thesis]

276903

a

Y