Finestructure and turbulence in the deep ocean
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution January 1977 Millimeter scale fluctuations in refractive index recorded with a freely sinking shadowgraph system are c...
Main Author: | |
---|---|
Format: | Thesis |
Language: | English |
Published: |
Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
1977
|
Subjects: | |
Online Access: | https://hdl.handle.net/1912/3984 |
id |
ftwhoas:oai:darchive.mblwhoilibrary.org:1912/3984 |
---|---|
record_format |
openpolar |
spelling |
ftwhoas:oai:darchive.mblwhoilibrary.org:1912/3984 2023-05-15T17:32:04+02:00 Finestructure and turbulence in the deep ocean Hendricks, Peter J. Eastern North Atlantic 1977-01 application/pdf https://hdl.handle.net/1912/3984 en_US eng Massachusetts Institute of Technology and Woods Hole Oceanographic Institution WHOI Theses https://hdl.handle.net/1912/3984 doi:10.1575/1912/3984 doi:10.1575/1912/3984 Ocean temperature Oceanic mixing Salinity Turbulence Atlantis II (Ship : 1963-) Cruise AII76 Thesis 1977 ftwhoas https://doi.org/10.1575/1912/3984 2022-05-28T22:58:09Z Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution January 1977 Millimeter scale fluctuations in refractive index recorded with a freely sinking shadowgraph system are correlated with finestructure profiles of temperature, salinity and density and compared to models of ocean turbulence. Images with vertically aligned periodic structure, called bands, are identified as salt fingers, while others with chaotic structure are turbulent. Images are found on interfaces that are 1-10m thick and have gradients at least several times the mean. From 6 profiles in the Mediterranean Outflow region of the eastern North Atlantic between 1.0 and 1.9 km depth, 398 interfaces have been identified and a significant fraction (about 1/3) of these have detectable images. High contrast images, including bands, are most often found below warm, saline intrusions and within stepped structure where there is a regular sequence of homogeneous mixed layers separated by interfaces. As the interfacial salinity gradient increases in the sense that allows salt finger convection, the fraction of interfaces with images increases. The horizontal spacing of bands (~5 mm) is consistent with calculated salt finger diameter. The calculated and observed length of ocean salt fingers (10-20 cm) is a small fraction of the interface thickness. High levels of small scale variability in the shadowgraphs is reflected in high levels of variance in the finestructure band of the temperature spectra. The temperature gradient spectra have a slope of -1, indicative of turbulence affected by buoyancy forces, and there is a relative peak at a wavelength near the observed salt finger length. The high contrast images are found at interfaces within the enhanced mean salinity gradient below saline intrusions. For very strong salinity gradients there is a solitary interface with intense images, but for weaker mean gradients the convection ... Thesis North Atlantic Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) Woods Hole, MA |
institution |
Open Polar |
collection |
Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) |
op_collection_id |
ftwhoas |
language |
English |
topic |
Ocean temperature Oceanic mixing Salinity Turbulence Atlantis II (Ship : 1963-) Cruise AII76 |
spellingShingle |
Ocean temperature Oceanic mixing Salinity Turbulence Atlantis II (Ship : 1963-) Cruise AII76 Hendricks, Peter J. Finestructure and turbulence in the deep ocean |
topic_facet |
Ocean temperature Oceanic mixing Salinity Turbulence Atlantis II (Ship : 1963-) Cruise AII76 |
description |
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution January 1977 Millimeter scale fluctuations in refractive index recorded with a freely sinking shadowgraph system are correlated with finestructure profiles of temperature, salinity and density and compared to models of ocean turbulence. Images with vertically aligned periodic structure, called bands, are identified as salt fingers, while others with chaotic structure are turbulent. Images are found on interfaces that are 1-10m thick and have gradients at least several times the mean. From 6 profiles in the Mediterranean Outflow region of the eastern North Atlantic between 1.0 and 1.9 km depth, 398 interfaces have been identified and a significant fraction (about 1/3) of these have detectable images. High contrast images, including bands, are most often found below warm, saline intrusions and within stepped structure where there is a regular sequence of homogeneous mixed layers separated by interfaces. As the interfacial salinity gradient increases in the sense that allows salt finger convection, the fraction of interfaces with images increases. The horizontal spacing of bands (~5 mm) is consistent with calculated salt finger diameter. The calculated and observed length of ocean salt fingers (10-20 cm) is a small fraction of the interface thickness. High levels of small scale variability in the shadowgraphs is reflected in high levels of variance in the finestructure band of the temperature spectra. The temperature gradient spectra have a slope of -1, indicative of turbulence affected by buoyancy forces, and there is a relative peak at a wavelength near the observed salt finger length. The high contrast images are found at interfaces within the enhanced mean salinity gradient below saline intrusions. For very strong salinity gradients there is a solitary interface with intense images, but for weaker mean gradients the convection ... |
format |
Thesis |
author |
Hendricks, Peter J. |
author_facet |
Hendricks, Peter J. |
author_sort |
Hendricks, Peter J. |
title |
Finestructure and turbulence in the deep ocean |
title_short |
Finestructure and turbulence in the deep ocean |
title_full |
Finestructure and turbulence in the deep ocean |
title_fullStr |
Finestructure and turbulence in the deep ocean |
title_full_unstemmed |
Finestructure and turbulence in the deep ocean |
title_sort |
finestructure and turbulence in the deep ocean |
publisher |
Massachusetts Institute of Technology and Woods Hole Oceanographic Institution |
publishDate |
1977 |
url |
https://hdl.handle.net/1912/3984 |
op_coverage |
Eastern North Atlantic |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
doi:10.1575/1912/3984 |
op_relation |
WHOI Theses https://hdl.handle.net/1912/3984 doi:10.1575/1912/3984 |
op_doi |
https://doi.org/10.1575/1912/3984 |
op_publisher_place |
Woods Hole, MA |
_version_ |
1766130000113696768 |