Water Mass and Acoustic Analysis of the East Greenland Current.
Two cluster analysis techniques, one heuristic and one iterative, are used to investigate the spatial coherence of the water masses of the East Greenland Current (EGC), in the vicinity of the East Greenland Polar Front (EGPF). Both techniques are shown to be generally reliable, although the iterativ...
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ftdtic:ADA175255 2023-05-15T16:03:33+02:00 Water Mass and Acoustic Analysis of the East Greenland Current. Clipson,James M NAVAL POSTGRADUATE SCHOOL MONTEREY CA 1986-09 text/html http://www.dtic.mil/docs/citations/ADA175255 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA175255 en eng http://www.dtic.mil/docs/citations/ADA175255 APPROVED FOR PUBLIC RELEASE DTIC AND NTIS Physical and Dynamic Oceanography *OCEAN CURRENTS *ACOUSTIC PROPERTIES SOURCES SPATIAL DISTRIBUTION WATER COHERENCE FORECASTING THESES VARIABLES SHALLOW WATER CLUSTERING PROFILES PATTERNS SEPARATION ACOUSTICS RANGE(DISTANCE) RAY TRACING ACOUSTIC VELOCITY NORTH ATLANTIC OCEAN WATER MASSES DEEP WATER BATHYTHERMOGRAPH DATA TRANSMISSION LOSS SONOBUOYS FRONTS(OCEANOGRAPHY) SOUND ANALYZERS East Greenland Current Acoustic Ducts Text 1986 ftdtic 2016-02-21T02:49:38Z Two cluster analysis techniques, one heuristic and one iterative, are used to investigate the spatial coherence of the water masses of the East Greenland Current (EGC), in the vicinity of the East Greenland Polar Front (EGPF). Both techniques are shown to be generally reliable, although the iterative technique is more consistent with classical oceanographic analyses. The techniques are applied to data to explore the grouping behavior of the water masses. They are also shown to have applications to multiple and single variable data. The cluster technique is shown to have applications in planning a sonobuoy pattern and in assessing the validity of XBT data prior to an acoustic forecast. Acoustic analysis shows that acoustic reciprocity does not hold for propagation in the waters of the EGC. Ranges from shallow to deep water are far in excess of those from deep to shallow water. Propagation across the EGPF is significantly different for normal and oblique cases. Propagation loss for oblique ranges is between 60 and 80 % of perpendicular ranges, mostly due to different source sound speed profiles. Three acoustic models, FACT, RAYMODE and PE are compared and contrasted. PE is found to be the most consistent and reliable, although both FACT and RAYMODE compare satisfactorily for propagation from shallow to deep water. For the reverse case, FACT overestimates ranges by a factor of two, whereas RAYMODE is exceedingly over optimistic in its forecast ranges. Keywords: Cluster analysis; Entity attribute; Separation distance; Ducting; Ray tracing. (Theses) Text East Greenland east greenland current Greenland North Atlantic Defense Technical Information Center: DTIC Technical Reports database Greenland |
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Defense Technical Information Center: DTIC Technical Reports database |
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ftdtic |
language |
English |
topic |
Physical and Dynamic Oceanography *OCEAN CURRENTS *ACOUSTIC PROPERTIES SOURCES SPATIAL DISTRIBUTION WATER COHERENCE FORECASTING THESES VARIABLES SHALLOW WATER CLUSTERING PROFILES PATTERNS SEPARATION ACOUSTICS RANGE(DISTANCE) RAY TRACING ACOUSTIC VELOCITY NORTH ATLANTIC OCEAN WATER MASSES DEEP WATER BATHYTHERMOGRAPH DATA TRANSMISSION LOSS SONOBUOYS FRONTS(OCEANOGRAPHY) SOUND ANALYZERS East Greenland Current Acoustic Ducts |
spellingShingle |
Physical and Dynamic Oceanography *OCEAN CURRENTS *ACOUSTIC PROPERTIES SOURCES SPATIAL DISTRIBUTION WATER COHERENCE FORECASTING THESES VARIABLES SHALLOW WATER CLUSTERING PROFILES PATTERNS SEPARATION ACOUSTICS RANGE(DISTANCE) RAY TRACING ACOUSTIC VELOCITY NORTH ATLANTIC OCEAN WATER MASSES DEEP WATER BATHYTHERMOGRAPH DATA TRANSMISSION LOSS SONOBUOYS FRONTS(OCEANOGRAPHY) SOUND ANALYZERS East Greenland Current Acoustic Ducts Clipson,James M Water Mass and Acoustic Analysis of the East Greenland Current. |
topic_facet |
Physical and Dynamic Oceanography *OCEAN CURRENTS *ACOUSTIC PROPERTIES SOURCES SPATIAL DISTRIBUTION WATER COHERENCE FORECASTING THESES VARIABLES SHALLOW WATER CLUSTERING PROFILES PATTERNS SEPARATION ACOUSTICS RANGE(DISTANCE) RAY TRACING ACOUSTIC VELOCITY NORTH ATLANTIC OCEAN WATER MASSES DEEP WATER BATHYTHERMOGRAPH DATA TRANSMISSION LOSS SONOBUOYS FRONTS(OCEANOGRAPHY) SOUND ANALYZERS East Greenland Current Acoustic Ducts |
description |
Two cluster analysis techniques, one heuristic and one iterative, are used to investigate the spatial coherence of the water masses of the East Greenland Current (EGC), in the vicinity of the East Greenland Polar Front (EGPF). Both techniques are shown to be generally reliable, although the iterative technique is more consistent with classical oceanographic analyses. The techniques are applied to data to explore the grouping behavior of the water masses. They are also shown to have applications to multiple and single variable data. The cluster technique is shown to have applications in planning a sonobuoy pattern and in assessing the validity of XBT data prior to an acoustic forecast. Acoustic analysis shows that acoustic reciprocity does not hold for propagation in the waters of the EGC. Ranges from shallow to deep water are far in excess of those from deep to shallow water. Propagation across the EGPF is significantly different for normal and oblique cases. Propagation loss for oblique ranges is between 60 and 80 % of perpendicular ranges, mostly due to different source sound speed profiles. Three acoustic models, FACT, RAYMODE and PE are compared and contrasted. PE is found to be the most consistent and reliable, although both FACT and RAYMODE compare satisfactorily for propagation from shallow to deep water. For the reverse case, FACT overestimates ranges by a factor of two, whereas RAYMODE is exceedingly over optimistic in its forecast ranges. Keywords: Cluster analysis; Entity attribute; Separation distance; Ducting; Ray tracing. (Theses) |
author2 |
NAVAL POSTGRADUATE SCHOOL MONTEREY CA |
format |
Text |
author |
Clipson,James M |
author_facet |
Clipson,James M |
author_sort |
Clipson,James M |
title |
Water Mass and Acoustic Analysis of the East Greenland Current. |
title_short |
Water Mass and Acoustic Analysis of the East Greenland Current. |
title_full |
Water Mass and Acoustic Analysis of the East Greenland Current. |
title_fullStr |
Water Mass and Acoustic Analysis of the East Greenland Current. |
title_full_unstemmed |
Water Mass and Acoustic Analysis of the East Greenland Current. |
title_sort |
water mass and acoustic analysis of the east greenland current. |
publishDate |
1986 |
url |
http://www.dtic.mil/docs/citations/ADA175255 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA175255 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
East Greenland east greenland current Greenland North Atlantic |
genre_facet |
East Greenland east greenland current Greenland North Atlantic |
op_source |
DTIC AND NTIS |
op_relation |
http://www.dtic.mil/docs/citations/ADA175255 |
op_rights |
APPROVED FOR PUBLIC RELEASE |
_version_ |
1766399228331950080 |