The Effect of Refraction on Oblique Angles of Multibeiam Echo-Sounders due to Sound Speed Changes Through the Water Column
This study investigated the effect of sound refraction in the water column on the accuracy of depths calculated from oblique swath angles of Multibeam Echosounders. This was accomplished by analysing data collected from the Tamar Estuary, Plymouth Sound and the Northeast Atlantic Ocean. Sound speed...
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University of Plymouth
2003
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ftunivplympearl:oai:pearl.plymouth.ac.uk:10026.2/1615 2023-05-15T17:41:33+02:00 The Effect of Refraction on Oblique Angles of Multibeiam Echo-Sounders due to Sound Speed Changes Through the Water Column Batton, Desiree' M. 2003 http://hdl.handle.net/10026.2/1615 en eng University of Plymouth http://hdl.handle.net/10026.2/1615 MSc Hydrography Thesis 2003 ftunivplympearl 2021-03-09T18:34:17Z This study investigated the effect of sound refraction in the water column on the accuracy of depths calculated from oblique swath angles of Multibeam Echosounders. This was accomplished by analysing data collected from the Tamar Estuary, Plymouth Sound and the Northeast Atlantic Ocean. Sound speed was computed from this data using the Chen & Millero, MacKenzie and Medwin formulae for the estimation of sound speed in sea water. Resulting values were graphed as sound velocity profiles and barographs thus visually illustrating discrepancies in sound speed estimation between the three sound speed formulae, leading to the conclusion that the sound speed formula used for the calculation of sound speed in the water column is a source of error related to the horizontal position in a charted depth. The last phase of analysis utilised ray tracing to compare the horizontal distance a sound ray refracted in the water column from sound pulses emitted at near vertical and oblique angles. In all analysis, the extent of refraction increased as the swath angle increased as did the error between the estimated sound speeds from the Chen & Millero, MacKenzie and Medwin formulae. This study establishes the sound velocity formula used to compute sound speed in the water column and refraction at large oblique angles of Multibearn sonars contribute to errors associated with outer swaths of Multibeam sonars, thus contributing error to the horizontal position of chart depths. Thesis Northeast Atlantic PEARL (Plymouth Electronic Archiv & ResearchLibrary, Plymouth University) |
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Open Polar |
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PEARL (Plymouth Electronic Archiv & ResearchLibrary, Plymouth University) |
op_collection_id |
ftunivplympearl |
language |
English |
topic |
MSc Hydrography |
spellingShingle |
MSc Hydrography Batton, Desiree' M. The Effect of Refraction on Oblique Angles of Multibeiam Echo-Sounders due to Sound Speed Changes Through the Water Column |
topic_facet |
MSc Hydrography |
description |
This study investigated the effect of sound refraction in the water column on the accuracy of depths calculated from oblique swath angles of Multibeam Echosounders. This was accomplished by analysing data collected from the Tamar Estuary, Plymouth Sound and the Northeast Atlantic Ocean. Sound speed was computed from this data using the Chen & Millero, MacKenzie and Medwin formulae for the estimation of sound speed in sea water. Resulting values were graphed as sound velocity profiles and barographs thus visually illustrating discrepancies in sound speed estimation between the three sound speed formulae, leading to the conclusion that the sound speed formula used for the calculation of sound speed in the water column is a source of error related to the horizontal position in a charted depth. The last phase of analysis utilised ray tracing to compare the horizontal distance a sound ray refracted in the water column from sound pulses emitted at near vertical and oblique angles. In all analysis, the extent of refraction increased as the swath angle increased as did the error between the estimated sound speeds from the Chen & Millero, MacKenzie and Medwin formulae. This study establishes the sound velocity formula used to compute sound speed in the water column and refraction at large oblique angles of Multibearn sonars contribute to errors associated with outer swaths of Multibeam sonars, thus contributing error to the horizontal position of chart depths. |
format |
Thesis |
author |
Batton, Desiree' M. |
author_facet |
Batton, Desiree' M. |
author_sort |
Batton, Desiree' M. |
title |
The Effect of Refraction on Oblique Angles of Multibeiam Echo-Sounders due to Sound Speed Changes Through the Water Column |
title_short |
The Effect of Refraction on Oblique Angles of Multibeiam Echo-Sounders due to Sound Speed Changes Through the Water Column |
title_full |
The Effect of Refraction on Oblique Angles of Multibeiam Echo-Sounders due to Sound Speed Changes Through the Water Column |
title_fullStr |
The Effect of Refraction on Oblique Angles of Multibeiam Echo-Sounders due to Sound Speed Changes Through the Water Column |
title_full_unstemmed |
The Effect of Refraction on Oblique Angles of Multibeiam Echo-Sounders due to Sound Speed Changes Through the Water Column |
title_sort |
effect of refraction on oblique angles of multibeiam echo-sounders due to sound speed changes through the water column |
publisher |
University of Plymouth |
publishDate |
2003 |
url |
http://hdl.handle.net/10026.2/1615 |
genre |
Northeast Atlantic |
genre_facet |
Northeast Atlantic |
op_relation |
http://hdl.handle.net/10026.2/1615 |
_version_ |
1766143170549121024 |