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Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Response Characteristics Of A Short Range, High Resolution, Digital Sonar Altimeter, Malcolm O. Green, John D. Boon Mar 1987

Response Characteristics Of A Short Range, High Resolution, Digital Sonar Altimeter, Malcolm O. Green, John D. Boon

Reports

The Datasonics Model ASA-920 digital sonar altimeter (DSA) is a compact, high frequency (1 MHz), short range (0.5 to 5 m) underwater sonar device originally designed as an altimeter for submersib1es. Wright et al. (1986) have used the DSA successfully to measure changes in relative bed elevation at a point on the shoreface prior to and during a storm. Fixed to a rigid mounting on the seabed, the DSA produces a digital output that is proportional to the transducer elevation above the bed. The purpose of this report is to describe the response characteristics of the DSA.


Potential Fish Egg Production By Mnemiopsis Leidyi Determined By Hydrography At The Chesapeake Bay Mouth, Harry D. Johnson Jan 1987

Potential Fish Egg Production By Mnemiopsis Leidyi Determined By Hydrography At The Chesapeake Bay Mouth, Harry D. Johnson

Dissertations, Theses, and Masters Projects

No abstract provided.


A Trophic Resource Analysis Of Dominant Benthic Microfauna Of The Lower Chesapeake Bay, Douglas Vernon Huggett Jan 1987

A Trophic Resource Analysis Of Dominant Benthic Microfauna Of The Lower Chesapeake Bay, Douglas Vernon Huggett

Dissertations, Theses, and Masters Projects

No abstract provided.


Primary Production And Temporal Variation In The Macrophytic Community Of A Tidal Freshwater Swamp, Bryan Keith Fowler Jan 1987

Primary Production And Temporal Variation In The Macrophytic Community Of A Tidal Freshwater Swamp, Bryan Keith Fowler

Dissertations, Theses, and Masters Projects

No abstract provided.


Life History Of The Goosefish, Lophius Americanus, Michael P. Armstrong Jan 1987

Life History Of The Goosefish, Lophius Americanus, Michael P. Armstrong

Dissertations, Theses, and Masters Projects

No abstract provided.


Shoreface And Beach Dynamics Of The Coastal Region From Cape Henry To False Cape, Virginia, L. D. Wright, C. S. Kim, C. S. Hardaway Jr., S. M. Kimball, M. O. Green Jan 1987

Shoreface And Beach Dynamics Of The Coastal Region From Cape Henry To False Cape, Virginia, L. D. Wright, C. S. Kim, C. S. Hardaway Jr., S. M. Kimball, M. O. Green

Reports

The processes which drive the beach and nearshore changes vary considerably in space and time. The spatial variability is the result of modulations of waves and wave induced processes by the complex topography of the shoreface and inner shelf fronting the beaches. In this study we employed a state-of-the-art computer model to evaluate the nature of these modifications and their impact on coastal processes. The model estimates wave modifications by shoaling, refraction, diffraction. and loss of wave energy by frictional interaction with the bottom.


Plume Monitoring Of Rappahannock And York Spit Channels, Baltimore Harbor And Channels: Phase 1, M. Nichols, R. J. Diaz, Et Al Jan 1987

Plume Monitoring Of Rappahannock And York Spit Channels, Baltimore Harbor And Channels: Phase 1, M. Nichols, R. J. Diaz, Et Al

Reports

A major element and concern necessary for evaluating the environmental impact of dredging operations is the dispersion of finegrained dredged material. The turbid plume generated by draghead agitation and by overflow processes from a hopper dredge can dictate the degree of potential adverse effects. Under certain environmental and aesthetic circumstances control of the plume may be advisable. Although turbid plumes produced by open water disposal operations have been evaluated in many investigations (e.g. Barnard. 1978). detailed field assessments of plumes produced by hopper dredging operations are scarce.


Field Measurements Of Tidal Currents, I664 Tunnel Axis, Hampton Roads, Virginia : A Report To Morrison-Knudsen/Interbeton, Physical Oceanography Division, Virginia Institute Of Marine Science Jan 1987

Field Measurements Of Tidal Currents, I664 Tunnel Axis, Hampton Roads, Virginia : A Report To Morrison-Knudsen/Interbeton, Physical Oceanography Division, Virginia Institute Of Marine Science

Reports

Currents in the region of Newport News Point of the James River were measured at the request of Morrison-Knudsen/Interbeton to examine maximum flood and ebb values during spring tides and determine first order relationships of current strengths and phase lags between this region and Chesapeake Bay Entrance predictions.


Monogenetic Trematodes From The Southern Pacific Ocean Polyopisthocotyleids From The Australian Fishes, The Subfamily Polylabrinae And Microcotylinae, W. A. Dillon, William J. Hargis Jr., Antonio E. Harrises Jan 1987

Monogenetic Trematodes From The Southern Pacific Ocean Polyopisthocotyleids From The Australian Fishes, The Subfamily Polylabrinae And Microcotylinae, W. A. Dillon, William J. Hargis Jr., Antonio E. Harrises

Reports

This eighth of a series of monogenetic trematodes from the Southern Pacific Ocean discusses two species of Monogenea from Australian waters. Polylabroides mylionis n. sp., from the gills of Mylio butcheri, is described. Neobivagina agonostomi (Sandars, 1945} Dillon and Hargis, 1965, from the gills of Aldrichett~ forsteri, is redescribed; a new locality record is reported for Neobivagina agonostomi.


Studies Of Pipefish Foraging In Simulated Seagrass Habitats, Clifford H. Ryer Jan 1987

Studies Of Pipefish Foraging In Simulated Seagrass Habitats, Clifford H. Ryer

Dissertations, Theses, and Masters Projects

Laboratory experiments determined the effects of two levels of habitat complexity upon pipefish (Syngnathus fuscus) foraging for amphipods. Habitats were composed of equal densities of either narrow (low complexity) or wide (high complexity) leafed artificial seagrass. The response to habitat, as measured by rate of encounter with amphipods, probability of attack after encounter, probability of success after attack, and overall rate of amphipod consumption, was determined for combinations of two fish size classes and three amphipod size classes. Small fish did not experience visually inhibitive effects in either habitat, while large fish had their visual fields impinged upon in the …


Low-Energy Bedload Transport By Combined Wave And Current Flow On A Southern Mid-Atlantic Bight Shoreface, Malcolm O. Green Jan 1987

Low-Energy Bedload Transport By Combined Wave And Current Flow On A Southern Mid-Atlantic Bight Shoreface, Malcolm O. Green

Dissertations, Theses, and Masters Projects

The control of the mean flow, wind-wave energy and wind-wave asymmetry on low-energy bedload transport magnitude, direction and divergence on a wave-dominated shoreface was investigated. The objective was to develop a mechanistic basis for postulated fairweather replenishment of the beach sediment prism by sediments derived from offshore. Fairweather currents were measured at 17.5-m and 22-m depth. Periods of competent flow were identified using a combined-flow boundary-layer model. Madsen and Grant's (1976) combined-flow bedload-transport model was used to calculate sediment fluxes after modification of the expression for instantaneous transport rate to include a threshold criterion; this was necessary since sediment is …


Population Structure Of The White Perch, Morone Americana, In Lower Chesapeake Bay As Inferred From Mitochondrial Dna Restriction Analysis, Brian W. Bowen Jan 1987

Population Structure Of The White Perch, Morone Americana, In Lower Chesapeake Bay As Inferred From Mitochondrial Dna Restriction Analysis, Brian W. Bowen

Dissertations, Theses, and Masters Projects

No abstract provided.


System Response Of A Nourished Beach In A Low-Energy Estuarine Environment, Gloucester Point, Virginia, Tracy Eanes Skrabal Jan 1987

System Response Of A Nourished Beach In A Low-Energy Estuarine Environment, Gloucester Point, Virginia, Tracy Eanes Skrabal

Dissertations, Theses, and Masters Projects

No abstract provided.


Clay Mineral Distribution And Source Discrimination Of Holocene Sediments In Lower Chesapeake Bay, Virginia, Stephen A. Skrabal Jan 1987

Clay Mineral Distribution And Source Discrimination Of Holocene Sediments In Lower Chesapeake Bay, Virginia, Stephen A. Skrabal

Dissertations, Theses, and Masters Projects

No abstract provided.


Interaction Of Long Waves And Nearshore Barred Topography--A Mechanism Of Bar Migration, Chang-Shik Kim Jan 1987

Interaction Of Long Waves And Nearshore Barred Topography--A Mechanism Of Bar Migration, Chang-Shik Kim

Dissertations, Theses, and Masters Projects

It has been widely observed in nature that longshore bar topography changes profile in the onshore-offshore direction. It is common for some bars to migrate onshore during post-storm phases and offshore during storms. Although the behavior of submarine bars has been widely reported, its mechanisms and forcings are far less clear. to determine the mechanism for bar migration or for the persistence of bar systems, a numerical model is developed, which accounts for the mass transport velocities in the bottom boundary layer induced by a family of combined long waves at surf-beat frequencies and wind waves. The present approach simulates …


Identification And Distribution Of Urophycis (Gill) And Phycis (Artedi) Larvae And Pelagic Juveniles In The Middle Atlantic Bight, Bruce Henry Comyns Jan 1987

Identification And Distribution Of Urophycis (Gill) And Phycis (Artedi) Larvae And Pelagic Juveniles In The Middle Atlantic Bight, Bruce Henry Comyns

Dissertations, Theses, and Masters Projects

No abstract provided.


The Respiratory Response Of Busycon Canaliculatum (L) To Seasonal Variation Of Water Temperature, Salinity, And Oxygen, Harry Gregory Polites Jan 1987

The Respiratory Response Of Busycon Canaliculatum (L) To Seasonal Variation Of Water Temperature, Salinity, And Oxygen, Harry Gregory Polites

Dissertations, Theses, and Masters Projects

No abstract provided.