You are here

Dissipation Processes in the Tongue of the Ocean

Title: Dissipation Processes in the Tongue of the Ocean.
35 views
6 downloads
Name(s): Hooper, James A., V, author
Dewar, William, professor directing thesis
Laurent, Louis St., committee member
Clayson, Carol Anne, committee member
Kostka, Joel, committee member
Department of Earth, Ocean and Atmospheric Sciences, degree granting department
Florida State University, degree granting institution
Type of Resource: text
Genre: Text
Issuance: monographic
Date Issued: 2011
Publisher: Florida State University
Place of Publication: Tallahassee, Florida
Physical Form: computer
online resource
Extent: 1 online resource
Language(s): English
Abstract/Description: The Tongue of the Ocean (TOTO) region located within the Bahamas archipelago is a relatively under-studied region in terms of both its biological and physical oceanographic characteristics. This region is comprised of a deep trough along with steep boundaries that are commonly associated with elevated turbulent dissipation rates, and #949;, when impacted by currents and internal waves. A prey-field mapping cruise took place in the fall between 9/15/2008 and 10/01/2008, consisting of a series of transects and 'clovers' to study the spatial and temporal variability. The region is characterized by a deep scattering layer (DSL), which is preyed on by nekton that serves as the food for beaked whale and other whale species. This study marks the first of its kind where concurrent measurements of acoustic backscatter and turbulence have been conducted for a nekton scattering layer well below the euphotic zone. In this novel study, turbulence data collected from a deep microstructure profiler are compared to biological and shear data collected by a 38 kHz Simrad EK 60 echosounder and a hydrographic Doppler sonar system, respectively. From these measurements, the primary processes responsible for the turbulent production in the TOTO region are assessed. The DSL around 500 m and a surface scattering layer (SSL) are investigated for raised and #949; values. Strong correlation between turbulence levels and scattering intensity of prey is generally found in the SSL with dissipation levels as large as ~10-7 W kg-1, three orders of magnitude above background levels. In the deep scattering layer, however, the correlations are relatively weak, but exhibit dissipation levels ~10-8 W kg-1. The absence of turbulence bursts of O(10-5 W kg-1) proposed to occur within dense biomass aggregations suggests biologically generated turbulence is not efficient by the marine biosphere. Areas of elevated turbulence have many implications from sustaining the abyssal stratification to transporting of nutrients and gases to and from the surface. We present an examination of the TOTO mixing levels with those from a typical open ocean site.
Identifier: FSU_migr_etd-7039 (IID)
Submitted Note: A Thesis submitted to the Department of Earth, Ocean, and Atmospheric Sciences in partial fulfillment of the requirements for the degree of Master of Science.
Degree Awarded: Spring Semester, 2011.
Date of Defense: March 31, 2011.
Bibliography Note: Includes bibliographical references.
Advisory Committee: William Dewar, Professor Directing Thesis; Louis St. Laurent, Committee Member; Carol Anne Clayson, Committee Member; Joel Kostka, Committee Member.
Subject(s): Earth sciences
Oceanography
Atmospheric sciences
Geophysics
Persistent Link to This Record: http://purl.flvc.org/fsu/fd/FSU_migr_etd-7039
Owner Institution: FSU

Choose the citation style.
Hooper, J. A. (2011). Dissipation Processes in the Tongue of the Ocean. Retrieved from http://purl.flvc.org/fsu/fd/FSU_migr_etd-7039