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  • 1
    Publication Date: 2022-05-25
    Description: The NOAA National Underseas Research Program at Rutgers University is establishing a Long-term Ecosystem Observatory off New Jersey in 15 meters of water. As part of a bottom boundary layer study at this site, WHOI deployed a bottom instrument frame during the winter of 1993-94. The bottom instrument carried a current meter, a vertical array of optical back scattering sensors, temperature, pressure and conductivity sensors and an Acoustical Backscattering Sensor. The deployment was partially successful as the acoustic system failed. The other instrumentation worked well for 3 weeks returning data on winter conditions at the site. The extreme winter waves ended the experiment by tipping the instrument over on its side. The optical instrumentation was calibrated with sediment from the site, and the results from the experiment presented.
    Description: Funding was provided by the National Oceanic and Atmospheric Administration through Contract No. 4-25020 to Rutgers/SUNY National Underseas Research Program.
    Keywords: Sediment transport ; LEO-15 ; Acoustic backscatter
    Repository Name: Woods Hole Open Access Server
    Type: Technical Report
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  • 2
    Publication Date: 2022-05-25
    Description: This report documents the work performed by the Woods Hole Oceanographic Institution (WHOI) and the Battelle Memorial Institute from August 1988 to December 1992 in the NSF sponsored development of an Integrated Seawater Sampler and Data Acquisition Prototype. After a 6-month initial design study, a prototype underwater profiing unit was designed and constructed, containing the water acquisition subsystem, CTD and altimeter, control circuitry and batteries. A standard WHOI CTD was adapted for use in the underwater unit and was interfaced to the underwater controller which had a telemetry module connecting ít with a deck control unit. This enabled CTD data to be logged in normal fashion on shipboard while additional commands and diagnostics were sent over the telemetry link to command the underwater unit's water sampling process and receive diagnostic information on system performance. The water sampling subsystem consisted of 36 trays, each containing a plastic sample bag, the pump and control circuitry. The sample bags, initially sealed in a chemically clean environment, were opened by pumping the water out of the tray, thus forcing water into the bag by ambient pressure. The command system could select any bag, and control the water sampling procss from the surface with diagnostic information on system altitude, depth, orientation and cable tension displayed in real time for operator information. At sea tests confirmed the operation of the electrical and control system. Problems were encountered with the bags and seals which were partially solved by further post cruise efforts. However, the bag closing mechanism requires further development, and numerous small system improvements identified during the cruises need to be implemented to produce an operational water sampler. Finally, initial design tor a water sampler handling and storage unit and water extraction system were developed but not implemented. The detailed discussion of the prototype water sampler design, testing and evaluation, and new bag testing result are presented.
    Description: Funding was provided by the National Science Foundation through Grant No. OCE8821977.
    Keywords: Seawater sampler ; Shipboard profiing system ; Chemical free sample bags
    Repository Name: Woods Hole Open Access Server
    Type: Technical Report
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  • 3
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    Woods Hole Oceanographic Institution
    Publication Date: 2022-05-25
    Description: The Massachusetts Bays Program made bottom pressure and water velocity observations in Massachusetts and Cape Cod Bays during 1990 and 1991. In the Bays, the sea surface elevation appeared to rise and fall in phase with equal amplitudes at each diurnal or semidiurnal tidal frequency. There is some amplification in Boston and Provincetown harbors. The semidiurnal tides (particularly the M2 constituent) dominate. Massachusetts and Cape Cod Bays are part of the Gulf of Maine/Bay of Fundy system which is resonant near the semidiurnal frequency. This resonance amplifies the importance of the semidiurnal tides so that diurnal and higher harmonic tides become negligible. The sea level tides force currents which move with the same frequencies, but whose amplitudes are affected by the bathymetry. The strongest currents exist in the channel between Race Point and Stellwagen Bank where tidal currents exceed 1 knot. Analysis of current records for their tidal signal is complicated by internal tides which contaminate the records. These internal waves at tidal frequency exist on the stratification in the water column, and disappear during winter well-mixed times. At other times they must be considered as a signifcant source of energy for mixing and resuspension of sediments.
    Keywords: Tides ; Currents ; Internal waves
    Repository Name: Woods Hole Open Access Server
    Type: Technical Report
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  • 4
    Publication Date: 2022-05-25
    Description: Author Posting. © IEEE, 2004. This article is posted here by permission of IEEE for personal use, not for redistribution. The definitive version was published in IEEE Journal of Oceanic Engineering 29 (2004): 1105-1130, doi:10.1109/JOE.2004.836998.
    Description: A field program to measure acoustic propagation characteristics and physical oceanography was undertaken in April and May 2001 in the northern South China Sea. Fluctuating ocean properties were measured with 21 moorings in water of 350- to 71-m depth near the continental slope. The sea floor at the site is gradually sloped at depths less than 90 m, but the deeper area is steppy, having gradual slopes over large areas that are near critical for diurnal internal waves and steep steps between those areas that account for much of the depth change. Large-amplitude nonlinear internal gravity waves incident on the site from the east were observed to change amplitude, horizontal length scale, and energy when shoaling. Beginning as relatively narrow solitary waves of depression, these waves continued onto the shelf much broadened in horizontal scale, where they were trailed by numerous waves of elevation (alternatively described as oscillations) that first appeared in the continental slope region. Internal gravity waves of both diurnal and semidiurnal tidal frequencies (internal tides) were also observed to propagate into shallow water from deeper water, with the diurnal waves dominating. The internal tides were at times sufficiently nonlinear to break down into bores and groups of high-frequency nonlinear internal waves.
    Description: This work was supported in part by grants from the U.S. Office of Naval Research, Physical Oceanography and Ocean Acoustics Programs, and by the National Science Council of Taiwan.
    Keywords: Baroclinic tides ; Internal waves ; Nonlinear waves
    Repository Name: Woods Hole Open Access Server
    Type: Article
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  • 5
    Publication Date: 2022-05-25
    Description: Author Posting. © Elsevier B.V., 2006. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Aquacultural Engineering 36 (2007): 137-148, doi:10.1016/j.aquaeng.2006.10.001.
    Description: A study is conducted to validate a numerical model for calculating mooring system tensions of a large fish farm containing 20 net pens in the absence of waves. The model is forced using measured current velocity values obtained outside of the farm. Mooring line tensions calculated with the numerical model are compared with load cell field data sets. The approach considers current velocity reduction and load characteristics that occur through the net pen system for both clean and fouled net conditions. Without accounting for the reduction, the numerical model produces excessively conservative results. With reduction, a substantial improvement occurs. Understanding these differences will help to establish appropriate safety factors when designing large marine fish farms using the model. Additional validation studies should be conducted with wave and current forcing to investigate the modeling large fish farms for exposed or open ocean sites.
    Description: The authors would also like to express sincere thanks the National Oceanic and Atmospheric Administration for funding this project through the Saltonstall-Kennedy program under Grant NAO3NMF4270183.
    Keywords: Mooring analysis ; Finite elements ; Flow reduction ; Fouled nets
    Repository Name: Woods Hole Open Access Server
    Type: Preprint
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  • 6
    Publication Date: 2022-05-25
    Description: © 2010 The Authors. This article is distributed under the terms of the Creative Commons Attribution-Noncommercial License. The definitive version was published in ICES Journal of Marine Science: Journal du Conseil 67 (2010): 365-378, doi:10.1093/icesjms/fsp262.
    Description: A commercial acoustic system, originally designed for seafloor applications, has been adapted for studying fish with swimbladders. The towed system contains broadband acoustic channels collectively spanning the frequency range 1.7–100 kHz, with some gaps. Using a pulse-compression technique, the range resolution of the echoes is ~20 and 3 cm in the lower and upper ranges of the frequencies, respectively, allowing high-resolution imaging of patches and resolving fish near the seafloor. Measuring the swimbladder resonance at the lower frequencies eliminates major ambiguities normally associated with the interpretation of fish echo data: (i) the resonance frequency can be used to estimate the volume of the swimbladder (inferring the size of fish), and (ii) signals at the lower frequencies do not depend strongly on the orientation of the fish. At-sea studies of Atlantic herring demonstrate the potential for routine measurements of fish size and density, with significant improvements in accuracy over traditional high-frequency narrowband echosounders. The system also detected patches of scatterers, presumably zooplankton, at the higher frequencies. New techniques for quantitative use of broadband systems are presented, including broadband calibration and relating target strength and volume-scattering strength to quantities associated with broadband signal processing.
    Description: The research was supported by the US Office of Naval Research, grants number N00014-04-1-0440 and N00014-04-1-0475, NOAA/CICOR cooperative agreement NA17RJ1223, NOAA/ National Marine Fisheries Service, and the J. Seward Johnson Chair of the WHOI Academic Programs Office.
    Keywords: Acoustic scattering ; Broadband ; Echosounder ; Fish ; Resonance
    Repository Name: Woods Hole Open Access Server
    Type: Article
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  • 7
    Publication Date: 2022-05-25
    Description: The 1995 Geoges Bank Stratification Study (GBSS) was the first intensive process study conducted as part of the U.S. GLOBEC Northwest Atlantic/Georges Bank field program. The GBSS was designed to investigate the physical processes which control the seasonal development of stratification along the southern flank of Georges Bank during spring and summer. Past work suggested that during this period, larval cod and haddock tended to aggregate to the thermocline on the southern flank where higher concentrations of their copepod prey were found. A moored array was deployed as part of GBSS to observe the onset and evolution of sesonal stratification over the southern flank with sufficient vertical and horizontal resolution that key physical processes could be identified and quantified. Moored current, temperature, and conductivity (salinity) measurements were made at three sites along the southern flank, one on the crest, and one on the northeast peak of the bank. Moored surface meteorological measurements were also made at one southern flank site to determine the surface wind stress and heat and moisture fluxes. The oceanographic and meteorological data collected with the GBSS array during January-August 1995 are presented in this report. Meteorological data collected on National Data Buoy Center environmental buoys 44011 (Georges Bank), 44008 (Nantucket Shoals), and 44005 (Gulf of Maine) are included in this report for completeness and comparison with the GBSS southern flank meteorological measurements.
    Description: Funding was provided by the National Science Foundation under Grant Numbers OCE-98-06379 and OCE-98-06445.
    Keywords: U.S. GLOBEC ; Moored array ; Parizeau (Ship) Cruise PAR94-018 ; Parizeau (Ship) Cruise PAR95-010 ; Endeavor (Ship: 1976-) Cruise EN256 ; Endeavor (Ship: 1976-) Cruise EN259 ; Endeavor (Ship: 1976-) Cruise EN260 ; Endeavor (Ship: 1976-) Cruise EN262 ; Endeavor (Ship: 1976-) Cruise EN269 ; Endeavor (Ship: 1976-) Cruise EN271 ; Endeavor (Ship: 1976-) Cruise EN274 ; Seward Johnson (Ship) Cruise SJ95-04 ; Seward Johnson (Ship) Cruise SJ95-06 ; Seward Johnson (Ship) Cruise SJ95-08
    Repository Name: Woods Hole Open Access Server
    Type: Technical Report
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  • 8
    Publication Date: 2022-05-25
    Description: The Nantucket Shoals Flux Experiment (NSFE79) was conducted across the continental shelf and upper slope south of Nantucket from March, 1979 to April , 1980 to measure the flow of shelf water from the Georges Bank/Gulf of Maine region into the Middle Atlantic Bight. Conceived as a cooperative field experiment involving the Northeast Fisheries Center (NMFS), U.S. Geological Survey (Woods Hole), University of New Hampshire, and the Woods Hole Oceanographic Institution, the experiment contained two principal components, a moored array of current meter and bottom instrumentation deployed at six locations across the shelf and upper slope spanning a depth range from 46 m to 810 m, and a series of 27 hydrographic surveys made along or near the moored array line during the experiment. A basic description of the NSFE79 hydrographic data has been given in Part 1 by Wright (1983). A description of the moored array components and the basic moored array data sets is presented here in Part 2.
    Description: The NEFC participation was supported by the NMFS Marine Resources Monitoring, Assessment, and Prediction (MARt-1AP) Program. The U.S. Bureau of Land Management (BLM) supported the USGS field and analysis component under t~emoranda of Understanding M550-MU6-79, M551-MU8- 24, M551-MU9-4, and M551-MU0-18. The WHO! and UNH field programs were supported by the National Science Foundation under Grants OCE 78-19513 and OCE 78-26229.
    Keywords: Oceanography ; Hydrography ; Ocean currents ; Moored arrays
    Repository Name: Woods Hole Open Access Server
    Type: Technical Report
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  • 9
    Publication Date: 2022-05-25
    Description: As part of the U.S. GLOBEC Northwest Atlantic/Georges Bank program, moorings were deployed on Georges Bank as part of the broad-scale survey component to help measure the temporal variability of both physical and biological characteristics on the Bank. The array consisted of a primary mooring site on the Southern Flank which was maintained for the full 5-year duration of the field program, plus secondary moorings, with fewer sensors and of shorter duration, in the well-mixed water on the Crest and in the cod/haddock spawning region on the Northeast Peak. Temperature and conductivity (salinity) were measured at 5-m intervals, ADCP velocity profiles were obtained with 1-m vertical resolution, and bio-optical packages (measuring fluorescence, optical transmission and photosynthetically active radiation) were deployed at 10-m and 40-m depths. Bottom pressure was measured at the Southern Flank site. The buoy design, sensors and mooring configuration is presented and discussed below, and the data obtained is presented and discussed in an accompanying reports “U.S. GLOBEC Georges Bank Long-Term Moored Program: Part 2 – Yearly Data Summary and Report,” and “U.S. GLOBEC Georges Bank Long-Term Moored Program: Part 3 – Data Summary.”
    Description: Funding was provided by the National Science Foundation under grant numbers OCE-93-13670, OCE-96-32348, OCE98-06379, OCE-98-06445 and OCE-02-27679.
    Keywords: GLOBEC ; Moorings ; Georges Bank ; Oceanus (Ship : 1975-) Cruise OC256 ; Oceanus (Ship : 1975-) Cruise OC276 ; Oceanus (Ship : 1975-) Cruise OC291 ; Oceanus (Ship : 1975-) Cruise OC321 ; Oceanus (Ship : 1975-) Cruise OC331 ; Oceanus (Ship : 1975-) Cruise OC333 ; Oceanus (Ship : 1975-) Cruise OC338 ; Seward Johnson (Ship) Cruise SJ95-04 ; Seward Johnson (Ship) Cruise SJ95-06 ; Knorr (Ship : 1970-) Cruise KN149 ; Endeavor (Ship: 1976-) Cruise EN208
    Repository Name: Woods Hole Open Access Server
    Type: Technical Report
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  • 10
    Publication Date: 2022-05-25
    Description: Author Posting. © IEEE, 2007. This article is posted here by permission of IEEE for personal use, not for redistribution. The definitive version was published in IEEE Journal of Oceanic Engineering 32 (2007): 150-166, doi:10.1109/JOE.2007.890956.
    Description: Several experiments to measure postimpact burial of seafloor mines by scour and fill have been conducted near the Woods Hole Oceanographic Institution's Martha's Vineyard Coastal Observatory (MVCO, Edgartown, MA). The sedimentary environment at MVCO consists of a series of rippled scour depressions (RSDs), which are large scale bedforms with alternating areas of coarse and fine sand. This allows simultaneous mine burial experiments in both coarse and fine sand under almost identical hydrodynamic forcing conditions. Two preliminary sets of mine scour burial experiments were conducted during winters 2001?2002 in fine sand and 2002?2003 in coarse sand with a single optically instrumented mine in the field of view of a rotary sidescan sonar. From October 2003 to April of 2004, ten instrumented mines were deployed along with several sonar systems to image mine behavior and to characterize bedform and oceanographic processes. In fine sand, the sonar imagery of the mines revealed that large scour pits form around the mines during energetic wave events. Mines fell into their own scour pits, aligned with the dominant wave crests and became level with the ambient seafloor after several energetic wave events. In quiescent periods, after the energetic wave events, the scour pits episodically infilled with mud. After several scour and infilling events, the scour pits were completely filled and a layer of fine sand covered both the mines and the scour pits, leaving no visible evidence of the mines. In the coarse sand, mines were observed to bury until the exposed height above the ripple crests was approximately the same as the large wave orbital ripple height (wavelengths of 50?125 cm and heights of 10?20 cm). A hypothesis for the physical mechanism responsible for this partial burial in the presence of large bedforms is that the mines bury until they present roughly the same hydrodynamic roughness as the orbital-scale bedforms present in coarse sand.
    Description: This work was supported in part by the U.S. Office of Naval Research under Grants N00014-01-10564 and N0004-01-1-0847, by the Department of Defense Presidential Early Career Award, and by the U.S. Naval Research Laboratory (NRL) Core funding under Program 061115N.
    Keywords: Acoustic imaging ; Mine burial ; Scour ; Sediments
    Repository Name: Woods Hole Open Access Server
    Type: Article
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