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Surficial Geology Of The Continental Shelf Off New Hampshire: Morphologic Features And Surficial Sediment, Larry G. Ward, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani, Rachel C. Morrison Jan 2021

Surficial Geology Of The Continental Shelf Off New Hampshire: Morphologic Features And Surficial Sediment, Larry G. Ward, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani, Rachel C. Morrison

Center for Coastal and Ocean Mapping

The continental shelf off New Hampshire (NH) in the Western Gulf of Maine (WGOM) is extremely complex and includes extensive bedrock outcrops, marine-modified glacial deposits, marine-formed shoals, seafloor plains, and associated features that are composed of a range of sediment types from mud to gravel. Furthermore, the physiography and composition of the seafloor frequently changes dramatically over relatively short distances (tens of meters). The complexity of the WGOM seafloor results from the interplay of glaciations, sea-level fluctuations, and marine processes (waves and currents). High-resolution multibeam echosounder (MBES) bathymetry and backscatter surveys, along with ground truth consisting of archived seismic reflection …


Northeast Bathymetry And Backscatter Compilation: Western Gulf Of Maine, Southern New England, And Long Island Sound, Larry G. Ward, Paul Johnson, Michael Bogonko, Zachary S. Mcavoy, Rachel C. Morrison Jan 2021

Northeast Bathymetry And Backscatter Compilation: Western Gulf Of Maine, Southern New England, And Long Island Sound, Larry G. Ward, Paul Johnson, Michael Bogonko, Zachary S. Mcavoy, Rachel C. Morrison

Center for Coastal and Ocean Mapping

High-resolution bathymetry is critical for mapping the surficial geology of the seafloor, identifying critical habitats, and assessing marine mineral resources such as sand and gravel. In 2016, a high-resolution bathymetry map was developed for the western Gulf of Maine (WGOM) utilizing all available multibeam echosounder (MBES) surveys, as well as several older extant surveys (Western Gulf of Maine Bathymetry and Backscatter Synthesis, Ward et al., 2016). As part of that effort, a backscatter mosaic also was developed for a subset of the MBES surveys. The backscatter synthesis did not include all of the MBES surveys due to low quality of …


Analysis Of Vibracores From The New Hampshire Continental Shelf From 1984 And 1988, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani Jan 2021

Analysis Of Vibracores From The New Hampshire Continental Shelf From 1984 And 1988, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani

Center for Coastal and Ocean Mapping

During this study, the twenty-three vibracores taken in 1984 and 1988 were reexamined, original descriptions verified and significantly expanded, and the cores sampled to provide complete grain size data (i.e. the original sediment grain size analyses were limited). The vibracores were grouped by location with respect to major physiographic features (geoforms) or surficial sediment type including Offshore Marine-Modified Glacial Features (Drumlins and Lodgement Till Deposits), Northern Sand Body, Isles of Shoals, Nearshore Marine-Modified Glacial Features (Eskers and Drumlins), Nearshore Sheet Sand, and Offshore Seafloor Plain.

The Northern Sand Body (NSB), located near the Isles of Shoals ~10 km from shore, …


Observations Of Backscatter From Sand And Gravel Seafloors Between 170-250 Khz, Thomas C. Weber, Larry G. Ward Oct 2015

Observations Of Backscatter From Sand And Gravel Seafloors Between 170-250 Khz, Thomas C. Weber, Larry G. Ward

Center for Coastal and Ocean Mapping

Interpreting observations of frequency-dependence in backscatter from the seafloor offers many challenges, either because multiple frequencies are used for different observations that will later be merged or simply because seafloor scattering models are not well-understood above 100 kHz. Hindering the understanding of these observations is the paucity of reported, calibratedacoustic measurements above 100 kHz. This manuscript seeks to help elucidate the linkages between seafloor properties and frequency-dependent seafloor backscatter by describing observations of backscatter collected from sand, gravel, and bedrock seafloors at frequencies between 170 and 250 kHz and at a grazing angle of 45°. Overall, the frequency dependence appeared …


Initiatives In Using Crowdsourcing, Satellite Derived Bathymetry, And Other Non-Traditional Hydrographic/Bathymetric Measurements, Anthony Klemm, Shachak Pe'eri, John Nyberg Oct 2015

Initiatives In Using Crowdsourcing, Satellite Derived Bathymetry, And Other Non-Traditional Hydrographic/Bathymetric Measurements, Anthony Klemm, Shachak Pe'eri, John Nyberg

Center for Coastal and Ocean Mapping

No abstract provided.


Reconnaissance Surveying Using Satellite-Derived Bathymetry, Shachak Pe'eri, Patrick Keown, Michael Gonsalves Oct 2015

Reconnaissance Surveying Using Satellite-Derived Bathymetry, Shachak Pe'eri, Patrick Keown, Michael Gonsalves

Center for Coastal and Ocean Mapping

False Pass, AK, USA, is the eastern-most passage through the Aleutian Islands between the Bering Sea and the Pacific Ocean and provides a passage for small to mid-size vessels. The passage is considered an alternative route to Unimak Pass, AK for vessels from mainland Alaska and is estimated to be shorter by 160 to 240km. False Pass is closed every winter due to sea-ice cover that freezes the inlet system around OctoberNovember and melts only towards the spring (around March). As a result, the soft sediment of the seafloor contains mud and sand that may change the path of the …


Chart Adequacy: Workshop And Gebco Training, Limor Gur-Arieh, Yusoff Kamaruddin, Amon Kimeli, Anthony Klemm, Hirokazu Kurita, Shachak Pe'eri, Indra Budi Prasetyawan, Jae-Young Roh, Jaya Roperez, Nilupa Samarakoon, Jaqueline Sydenham, Maxlimer Vallee, Rochelle A. Wigley Oct 2015

Chart Adequacy: Workshop And Gebco Training, Limor Gur-Arieh, Yusoff Kamaruddin, Amon Kimeli, Anthony Klemm, Hirokazu Kurita, Shachak Pe'eri, Indra Budi Prasetyawan, Jae-Young Roh, Jaya Roperez, Nilupa Samarakoon, Jaqueline Sydenham, Maxlimer Vallee, Rochelle A. Wigley

Center for Coastal and Ocean Mapping

In July, 2015 the first NOAA Chart Adequacy Workshop was held in Silver Spring, Maryland, USA. Following a three-day workshop (14th to 16th July, 2015), four Nippon Foundation GEBCO students stayed at NOAA for an additional 10-day training at Office of Coast Survey’s Marine Chart Division. The key objective of the NOAA Chart Adequacy Workshop was to demonstrate techniques to evaluate the suitability of nautical chart products using chart quality information and publicly-available information. The attendees were cartographers, hydrographers and potential chart producers from hydrographic offices and government agencies around the world. The nations of the participants in the workshop …


Reconnaissance Surveying Of Bechevin Bay, Ak Using Satellite-Derived Bathymetry, Shachak Pe'eri, Patrick Keown, Leland P. Snyder, Michael Gonsalves, John Nyberg Mar 2015

Reconnaissance Surveying Of Bechevin Bay, Ak Using Satellite-Derived Bathymetry, Shachak Pe'eri, Patrick Keown, Leland P. Snyder, Michael Gonsalves, John Nyberg

Center for Coastal and Ocean Mapping

Recently, a remote sensing study has been conducted over Bechevin Bay Channel, Alaska as part of a collaboration project between NOAA and the U.S. Coast Guard (USCG). The goal of the study to develop a procedure to prioritize survey areas and plan the annual deployment of Aids to Navigation (AtoN) along the channel. Bechevin Bay is considered a priority for marine surveying because it constitutes the easternmost passage through the Aleutians from the Bering Sea to the Gulf of Alaska. The channel is located in a mud flat area, where every winter the passage is closed due to ice cover. …


Multibeam Mapping Of Feature Rich Seafloor In The U.S. Pacific Remote Islands Marine National Monument And On Mendocino Ridge Off The California Coast, Andy Armstrong, James V. Gardner, Brian R. Calder, Giuseppe Masetti Mar 2015

Multibeam Mapping Of Feature Rich Seafloor In The U.S. Pacific Remote Islands Marine National Monument And On Mendocino Ridge Off The California Coast, Andy Armstrong, James V. Gardner, Brian R. Calder, Giuseppe Masetti

Center for Coastal and Ocean Mapping

No abstract provided.


S-100 Overlays: A Brave New World?, Lee Alexander, C. Mcleay Mar 2015

S-100 Overlays: A Brave New World?, Lee Alexander, C. Mcleay

Center for Coastal and Ocean Mapping

Marine Information Overlay (MIO) is a generic term used to describe chart and navigation related information that supplement the content that is already contained in an ENC. This includes both static and dynamic information such as tide/water level, current flow, meteorological, oceanographic, and environmental protection. With the advent of S-100 and S-101, there is increased interest in providing a wide variety of ‘new’ overlay information. This paper provides a brief history of S-57 MIOs. Examples of navigational and non-navigation MIOs are given in terms of how currently used, by who, and for what purpose. Recommendations are provided for making a …


Nautical Chart Adequacy Evaluation Using Publicly-Available Data, Anthony Klemm, Shachak Pe'eri, Ricardo Freire, John Nyberg, Shep M. Smith Lt Mar 2015

Nautical Chart Adequacy Evaluation Using Publicly-Available Data, Anthony Klemm, Shachak Pe'eri, Ricardo Freire, John Nyberg, Shep M. Smith Lt

Center for Coastal and Ocean Mapping

The International Hydrographic Office (IHO) C-55 publication communicates the need to improve the collection, quality and availability of hydrographic data world-wide, while also monitoring and rectifying possible deficiencies and shortcomings that are presented on the chart. This task of evaluating the adequacy of nautical chart products poses a challenge to many national hydrographic offices. This stems from the dearth of readily available spatial information: namely, the lack of reliable and accessible vessel traffic data, and little means to assess the changing nature of both near-shore bathymetry and shoreline in a simple and reliable manner. In this paper, we present the …


Euclidean Reconstruction Of Natural Underwater Scenes Using Optic Imagery Sequence, Han Hu Jan 2015

Euclidean Reconstruction Of Natural Underwater Scenes Using Optic Imagery Sequence, Han Hu

Center for Coastal and Ocean Mapping

The development of maritime applications require monitoring, studying and preserving of detailed and close observation on the underwater seafloor and objects. Stereo vision offers advanced technologies to build 3D models from 2D still overlapping images in a relatively inexpensive way. However, while image stereo matching is a necessary step in 3D reconstruction procedure, even the most robust dense matching techniques are not guaranteed to work for underwater images due to the challenging aquatic environment. In this thesis, in addition to a detailed introduction and research on the key components of building 3D models from optic images, a robust modified quasi-dense …


Arctic Ocean Bathymetry: A Necessary Geospatial Framework, Martin Jakobsson, Larry A. Mayer, Dave Monahan Jan 2015

Arctic Ocean Bathymetry: A Necessary Geospatial Framework, Martin Jakobsson, Larry A. Mayer, Dave Monahan

Center for Coastal and Ocean Mapping

Most ocean science relies on a geospatial infrastructure that is built from bathymetry data collected from ships underway, archived, and converted into maps and digital grids. Bathymetry, the depth of the seafloor, besides having vital importance to geology and navigation, is a fundamental element in studies of deep water circulation, tides, tsunami forecasting, upwelling, fishing resources, wave action, sediment transport, environmental change, and slope stability, as well as in site selection for platforms, cables, and pipelines, waste disposal, and mineral extraction. Recent developments in multibeam sonar mapping have so dramatically increased the resolution with which the seafloor can be portrayed …


Nippon Foundation / Gebco Indian Ocean Bathymetric Compilation Project, Rochelle A. Wigley, Norhizam Hassan, Mohammad Chowdhury, Roshan Ranaweera, Xinh Le Sy, Hemanaden Runghen, Jan Erik Arndt Dec 2014

Nippon Foundation / Gebco Indian Ocean Bathymetric Compilation Project, Rochelle A. Wigley, Norhizam Hassan, Mohammad Chowdhury, Roshan Ranaweera, Xinh Le Sy, Hemanaden Runghen, Jan Erik Arndt

Center for Coastal and Ocean Mapping

The Indian Ocean Bathymetric Compilation (IOBC) project, undertaken by Nippon Foundation / GEBCO Scholars, is focused on building a regional bathymetric data compilation, of all publically-available bathymetric data within the Indian Ocean region from 30°N to 60° S and 10° to 147° E. One of the objectives of this project is the creation of a network of Nippon Foundation / GEBCO Scholars working together, derived from the thirty Scholars from fourteen nations bordering on the Indian Ocean who have graduated from this Postgraduate Certificate in Ocean Bathymetry (PCOB) training program training program at the University of New Hampshire. The IOBC …


Nippon Foundation/Gebco Postgraduate Certificate In Ocean Bathymetry, Rochelle A. Wigley Oct 2014

Nippon Foundation/Gebco Postgraduate Certificate In Ocean Bathymetry, Rochelle A. Wigley

Center for Coastal and Ocean Mapping

No abstract provided.


R/V Sikuliaq Em302 And Em710 Multibeam Echosounder System Shipboard Acceptance Tests - Skq201400l3, Paul Johnson, Ashton F. Flinders, Samuel F. Greenaway Sep 2014

R/V Sikuliaq Em302 And Em710 Multibeam Echosounder System Shipboard Acceptance Tests - Skq201400l3, Paul Johnson, Ashton F. Flinders, Samuel F. Greenaway

Center for Coastal and Ocean Mapping

No abstract provided.


U.S. Extended Continental Shelf Cruise To Map Gaps In Kela And Karin Ridges, Johnston Atoll, Equatorial Pacific Ocean, James V. Gardner, Andy Armstrong Sep 2014

U.S. Extended Continental Shelf Cruise To Map Gaps In Kela And Karin Ridges, Johnston Atoll, Equatorial Pacific Ocean, James V. Gardner, Andy Armstrong

Center for Coastal and Ocean Mapping

The objectives for cruise KM14-17 are to map the bathymetry of two gaps in two submarine ridges in the vicinity of Johnston Atoll. One ridge gap occurs along the informally named Keli Ridge (Hein et al., 2005) south of Johnston Atoll and the other ridge gap occurs north of Johnston Atoll that separates Sculpin Ridge (also informally called Karin Ridge) and Horizon Ridge, all in the central equatorial Pacific (Fig. 1). The cruise took advantage of a scheduled dead-head transit from Papeete, Tahiti to Honolulu, Hawai’i that could be extended for 5 days to include the planned mapping. The mapping …


Enhanced Coastal Mapping Using Lidar Waveform Features, Christopher Parrish, Jeffrey A. Rogers, Larry G. Ward, Jennifer A. Dijkstra Jun 2014

Enhanced Coastal Mapping Using Lidar Waveform Features, Christopher Parrish, Jeffrey A. Rogers, Larry G. Ward, Jennifer A. Dijkstra

Center for Coastal and Ocean Mapping

No abstract provided.


Satellite-Derived Bathymetry Using Multiple Images: The Alaska North Slope Case Study, Shachak Pe'eri, Shep M. Smith Lt, Leland P. Snyder, Brian Madore May 2014

Satellite-Derived Bathymetry Using Multiple Images: The Alaska North Slope Case Study, Shachak Pe'eri, Shep M. Smith Lt, Leland P. Snyder, Brian Madore

Center for Coastal and Ocean Mapping

Currently, charting data in much of the U.S. Arctic North Slope is inadequate or nonexistent and most of its areas have not been updated since the early-1950s. Although the charting infrastructure is out of date, ship transportation (such as, fishing and transit between the towns) has increased. NOAA conducted a preliminary multibeam survey in 2013 that reached Point Barrow, AK. However, all the Arctic North Slope remained untouched. Previous studies have shown that satellite-derived bathymetry (SDB) is a useful reconnaissance tool in tropical and sub-tropical waters in clear water conditions, especially over sandy seafloor. However, it is very difficult to …


Pose Detection And Control Of Multiple Unmanned Underwater Vehicles Using Optical Feedback, Firat Eren, Shachak Pe'eri, Yuri Rzhanov, May-Win Thein, Barbaros Celikkol Apr 2014

Pose Detection And Control Of Multiple Unmanned Underwater Vehicles Using Optical Feedback, Firat Eren, Shachak Pe'eri, Yuri Rzhanov, May-Win Thein, Barbaros Celikkol

Center for Coastal and Ocean Mapping

This paper proposes pose detection and control algorithms in order to control the relative pose between two Unmanned Underwater Vehicles (UUVs) using optical feedback. The leader UUV is configured to have a light source at its crest which acts as a guiding beacon for the follower UUV which has a detector array at its bow. Pose detection algorithms are developed based on a classifier, such as the Spectral Angle Mapper (SAM), and chosen image parameters. An archive look-up table is constructed for varying combinations of 5-degree-of-freedom (DOF) motion (i.e., translation along all three coordinate axes as well as pitch and …


Caratterizzazione Dell’Ambiente Marino Dei Campi Flegrei. Risultati Preliminari Della Campagna Oceanografica Ricamar 2013, M. Grassi, C. Carmisciano, L. Cocchi, L. Dialti, M. Filippone, Matteo Guideri, Roberta Ivaldi, Giuseppe Masetti, F. Muccini, M. Pratellesi, E. Ricci, Paolo Stefanelli Nov 2013

Caratterizzazione Dell’Ambiente Marino Dei Campi Flegrei. Risultati Preliminari Della Campagna Oceanografica Ricamar 2013, M. Grassi, C. Carmisciano, L. Cocchi, L. Dialti, M. Filippone, Matteo Guideri, Roberta Ivaldi, Giuseppe Masetti, F. Muccini, M. Pratellesi, E. Ricci, Paolo Stefanelli

Center for Coastal and Ocean Mapping

The caldera of the Phlegraean Fields (also known as Campi Flegrei) is one of the most dangerous and populated volcanic area in the world, covering an area that comprises the western part of Naples and the Gulf of Pozzuoli. The main peculiarity of current volcanic activity is the gradual and periodic lift (positive or negative) of part of the Earth's surface (bradyseism) combined, only during the positive phase, with a strong sismicity and surficial hydrotermal activity. Deformative models, calibrated using land-based measurements, highlighted the Gulf of Pozzuoli as the area with the largest deformation. Although the network of monitoring sensors …


Alb Evaluation For Noaa Charting Requirements, Gretchen Imahori, Shachak Pe'eri, Christopher E. Parrish Nov 2013

Alb Evaluation For Noaa Charting Requirements, Gretchen Imahori, Shachak Pe'eri, Christopher E. Parrish

Center for Coastal and Ocean Mapping

The National Oceanic and Atmospheric Administration (NOAA) acquires hydrographic data around the coasts of the US and its territories using in-house surveys and contracting resources. Hydrographic data are primarily collected using sonar systems, while a small percent is acquired via Airborne Lidar Bathymetry (ALB) for nearshore areas. NOAA has an ongoing requirement, as per the Coast and Geodetic Survey Act of 1947, to survey nearshore areas as part of its coastal mapping activities, including updating nautical charts, creating hydrodynamic models and supporting coastal planning and habitat mapping. NOAA has initiated a project to investigate the potential use of ALB data …


A Detailed Seabed Signature From Hurricane Sandy Revealed In Bedforms And Scour, Arthur Trembanis, Carter Duval, Jonathan Beaudoin, Val E. Schmidt, Doug Miller, Larry A. Mayer Oct 2013

A Detailed Seabed Signature From Hurricane Sandy Revealed In Bedforms And Scour, Arthur Trembanis, Carter Duval, Jonathan Beaudoin, Val E. Schmidt, Doug Miller, Larry A. Mayer

Center for Coastal and Ocean Mapping

On 30 October 2012, Hurricane Sandy made landfall near Brigantine New Jersey bringing widespread erosion and damage to the coastline. We have obtained a unique set of high-resolution before and after storm measurements of seabed morphology and in situhydrodynamic conditions (waves and currents) capturing the impact of the storm at an inner continental shelf field site known as the “Redbird reef”. Understanding the signature of this storm event is important for identifying the impacts of such events and for understanding the role that such events have in the transport of sediment and marine debris on the inner continental shelf. …


Gradual Generalization Of Nautical Chart Contours With A Cube B-Spline Snake Model, Dandan Miao, Brian R. Calder Sep 2013

Gradual Generalization Of Nautical Chart Contours With A Cube B-Spline Snake Model, Dandan Miao, Brian R. Calder

Center for Coastal and Ocean Mapping

—B-spline snake methods have been used in cartographic generalization in the past decade, particularly in the generalization of navigational charts where this method yields good results with respect to the shoal-bias rules for generalization of chart contours. However, previous studies only show generalization results at particular generalization (or scale) levels, and the user can only see two conditions: before the generalization and after generalization, but nothing in between. This paper presents an improved method of using B-spline snakes for generalization in the context of nautical charts, where the generalization process is done gradually, and the user can see the complete …


Designing Improved Sediment Transport Visualizations, Chris Englert, Thomas J. Butkiewicz, Larry A. Mayer, Val E. Schmidt, Jonathan Beaudoin, Arthur Trembanis, Carter Duval Sep 2013

Designing Improved Sediment Transport Visualizations, Chris Englert, Thomas J. Butkiewicz, Larry A. Mayer, Val E. Schmidt, Jonathan Beaudoin, Arthur Trembanis, Carter Duval

Center for Coastal and Ocean Mapping

Monitoring, or more commonly, modeling of sediment transport in the coastal environment is a critical task with relevance to coastline stability, beach erosion, tracking environmental contaminants, and safety of navigation. Increased intensity and regularity of storms such as Superstorm Sandy heighten the importance of our understanding of sediment transport processes. A weakness of current modeling capabilities is the ability to easily visualize the result in an intuitive manner. Many of the available visualization software packages display only a single variable at once, usually as a two-dimensional, plan-view cross-section. With such limited display capabilities, sophisticated 3D models are undermined in both …


Evaluating The Usace's Ncmp For Noaa Charting Operations, Gretchen Imahori, Shachak Pe'eri, Christopher Parrish, Toshi Wozumi, Stephen A. White, Inseong Jeong, Christopher L. Macon Aug 2013

Evaluating The Usace's Ncmp For Noaa Charting Operations, Gretchen Imahori, Shachak Pe'eri, Christopher Parrish, Toshi Wozumi, Stephen A. White, Inseong Jeong, Christopher L. Macon

Center for Coastal and Ocean Mapping

No abstract provided.


Satellite-Derived Bathymetry: A Reconnaissance Tool For Hydrography, Shachak Pe'eri, Christopher Parrish, Lee Alexander, Andy Armstrong Aug 2013

Satellite-Derived Bathymetry: A Reconnaissance Tool For Hydrography, Shachak Pe'eri, Christopher Parrish, Lee Alexander, Andy Armstrong

Center for Coastal and Ocean Mapping

No abstract provided.


Characterization Of Optical Communication In A Leader-Follower Unmanned Underwater Vehicle Formation, Firat Eren, Shachak Pe'eri, May-Win Thein Jun 2013

Characterization Of Optical Communication In A Leader-Follower Unmanned Underwater Vehicle Formation, Firat Eren, Shachak Pe'eri, May-Win Thein

Center for Coastal and Ocean Mapping

As part of the research to development an optical communication design of a leader-follower formation between unmanned underwater vehicles (UUVs), this paper presents light field characterization and design configuration of the hardware required to allow the use of distance detection between UUVs. The study specifically is targeting communication between remotely operated vehicles (ROVs). As an initial step in this study, the light field produced from a light source mounted on the leader UUV was empirically characterized and modeled. Based on the light field measurements, a photo-detector array for the follower UUV was designed. Evaluation of the communication algorithms to monitor …


Optimizing Resolution And Uncertainty In Bathymetric Sonar Systems, Val E. Schmidt, Thomas C. Weber, Xavier Lurton Jun 2013

Optimizing Resolution And Uncertainty In Bathymetric Sonar Systems, Val E. Schmidt, Thomas C. Weber, Xavier Lurton

Center for Coastal and Ocean Mapping

Bathymetric sonar systems (whether multibeam or phase-differencing sidescan) contain an inherent trade-off between resolution and uncertainty. Systems are traditionally designed with a fixed spatial resolution, and the parameter settings are optimized to minimize the uncertainty in the soundings within that constraint. By fixing the spatial resolution of the system, current generation sonars operate sub-optimally when the SNR is high, producing soundings with lower resolution than is supportable by the data, and inefficiently when the SNR is low, producing high-uncertainty soundings of little value. Here we propose fixing the sounding measurement uncertainty instead, and optimizing the resolution of the system within …


Near Resonance Acoustic Scattering From Organized Schools Of Juvenile Atlantic Bluefin Tuna (Thunnus Thynnus), Thomas C. Weber, Molly Lutcavage, Madeline L. Schroth-Miller Jun 2013

Near Resonance Acoustic Scattering From Organized Schools Of Juvenile Atlantic Bluefin Tuna (Thunnus Thynnus), Thomas C. Weber, Molly Lutcavage, Madeline L. Schroth-Miller

Center for Coastal and Ocean Mapping

Schools of Atlantic bluefin tuna (Thunnus thynnus) can exhibit highly organized spatial structure within the school. This structure was quantified for dome shaped schools using both aerial imagery collected from a commercial spotter plane and 400 kHz multibeam echo sounder data collected on a fishing vessel in 2009 in Cape Cod Bay, MA. Observations from one school, containing an estimated 263 fish within an approximately ellipsoidal volume of 1900 m3, were used to seed an acoustic model that estimated the school target strength at frequencies between 10 and 2000 Hz. The fish's swimbladder resonance was estimated to occur at approximately …