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Integral Equation Approach To Tropical Ocean Dynamics: Part Ii-Rossby Wave Scattering From The Equatorial Atlantic Western Boundary, Paulo R. Holvorcem, Marcio L. Vianna Jan 1992

Integral Equation Approach To Tropical Ocean Dynamics: Part Ii-Rossby Wave Scattering From The Equatorial Atlantic Western Boundary, Paulo R. Holvorcem, Marcio L. Vianna

Journal of Marine Research

We develop a linear theory for the scattering of equatorial waves of a fixed frequency ω by islands and continental margins of arbitrary geometry by use of the boundary integral equation (BIE) method of Vianna and Holvorcem (Part I of this work). All the solutions of the equatorial β-plane dispersion relations at frequency ω are treated explicitly through the extensive use of exact Green's functions, so that the approach is more general and more rigorous than previous attempts to solve equatorial scattering problems, many of which employ the low-frequency and long-wave approximations. The numerical solution of the HIE is obtained …

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Numerical Modeling Of Larval Settlement In Turbulent Bottom Boundary Layers, Thomas F. Gross, Francisco E. Werner, James E. Eckman Jan 1992

Numerical Modeling Of Larval Settlement In Turbulent Bottom Boundary Layers, Thomas F. Gross, Francisco E. Werner, James E. Eckman

Journal of Marine Research

A time-dependent model of a tidal or wave bottom boundary layer has been developed to quantitatively evaluate the relative influences of vertical advection, turbulent mixing and shear, and near-bed behavior on settlement of planktonic larvae of benthic animals. The settlement behavior of larvae is modeled with a simple flux condition at the bed. This allows full time dependence to be included when determining settlement rates. For tidal oscillations, the model predicts that most settlement will occur at and near periods of slack water, whereas comparatively little settlement will occur during periods of stronger flow. In contrast, there should be little …

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Encounter Rate By Turbulent Shear Of Particles Similar In Diameter To The Kolmogorov Scale, P. S. Hill, A. R. M. Nowell, P. A. Jumars Jan 1992

Encounter Rate By Turbulent Shear Of Particles Similar In Diameter To The Kolmogorov Scale, P. S. Hill, A. R. M. Nowell, P. A. Jumars

Journal of Marine Research

To clarify the rate at which particles similar in size to the smallest eddies in a turbulent fluid encounter one another via turbulent shear, 3-D video motion analysis was used to make direct measurements of relative velocities between closely spaced, near-neutrally buoyant, 700-μm mean diameter, polystyrene latex spheres suspended in an oscillating-grid turbulence tank. Smallest eddy size, termed the Kolmogorov scale, λ, was estimated as (ν3/ε)0.25 where ν is fluid viscosity and ε is the dissipation rate of turbulent kinetic energy. For runs made in water, the effective particle diameter examined was ≈ 3–6 times …

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Expression And Function Of Zebra: The Epstein-Barr Viral Replication Activator, Naomi Taylor Dec 1991

Expression And Function Of Zebra: The Epstein-Barr Viral Replication Activator, Naomi Taylor

Yale Medicine Thesis Digital Library

Epstein-Barr virus (EBV) encodes a protein, ZEBRA, which enables the virus to switch from a latent to a lytic life cycle. ZEBRA expression was studied in lymphoid cells harboring either standard virus or a mixture of standard and defective viruses. ZEBRA protein could not be detected in cells latently infected with standard EBV but was constitutively expressed in cells containing both defective and standard EBV genomes. Experiments indicated that regulation of transcription of the ZEBRA gene (BZLF1) is a pivotal event in the control of EBV replication. ZEBRA specific BZLF1 transcripts were spontaneously expressed in cells harboring defective virus but …

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Measuring The Value Of Children By Sex And Age Using A Life Cycle Model Of Fertility, Namkee Ahn Nov 1991

Measuring The Value Of Children By Sex And Age Using A Life Cycle Model Of Fertility, Namkee Ahn

Discussion Papers

No abstract provided.

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Public Policy And Anthropometric Outcomes In The Côte D’Ivoire, Duncan Thomas, Victor Lavy, John Strauss Oct 1991

Public Policy And Anthropometric Outcomes In The Côte D’Ivoire, Duncan Thomas, Victor Lavy, John Strauss

Discussion Papers

No abstract provided.

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Nota Bene; Volume V, Number Iii, Yale University Library Oct 1991

Nota Bene; Volume V, Number Iii, Yale University Library

Nota Bene

Nota Bene is published during the academic year to acquaint the Yale community and others with the resources of the Yale Library.

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Angiosperm Ovules And Carpels: Their Characters And Polarities, Distribution In Basal Clades, And Structural Evolution, David Winship Taylor Aug 1991

Angiosperm Ovules And Carpels: Their Characters And Polarities, Distribution In Basal Clades, And Structural Evolution, David Winship Taylor

Postilla

Angiosperm ovules and carpels have numerous characters and character states, not all of which have been utilized in phylogenetic analyses. A character analysis of these two organs is performed, including description of characters and states, and character polarization to identify the ancestral states. In addition, the distributions of these states are examined in the Magnoliidae and putatively basal orders of Hamamelidae, Caryophyllidae, Dilleniidae, Rosidae, Alismatidae (sensu Cronquist 1981), and Liliiflorae (sensu Dahlgren et al. 1985). These support two hypotheses: the ancestral ovules were orthotropous, bitegmic and crassinucellar, based on current terminology; and ancestral carpels had ascidate morphology and one or …

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List Of Type Specimens In The Fish Collection At The Yale Peabody Museum, With A Brief History Of Ichthyology At Yale University, Jon Moore, Richard Boardman Aug 1991

List Of Type Specimens In The Fish Collection At The Yale Peabody Museum, With A Brief History Of Ichthyology At Yale University, Jon Moore, Richard Boardman

Postilla

All known type specimens in the fish collection of the Division of Vertebrate Zoology, Peabody Museum of Natural History published prior to 1991 are listed. There are a total of 925 specimens representing 190 nominal species including 159 holotypes, 2 lectotypes, 24 syntypes of 13 nominal species, and paratypes and paralectotypes of 65 nominal species now found in our collection. Most of these specimens were described by David S. Jordan, Louis L. Mowbray, Charles Breder, Albert E. Parr, James E. Morrow, and Alfred W. Ebeling. The large majority of specimens were formerly part of the Bingham Oceanographic Collection which was …

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New Observations On The Skull Of Hesperornis With Reconstructions Of The Bony Palate And Otic Region, Andrzej Elzanowski Aug 1991

New Observations On The Skull Of Hesperornis With Reconstructions Of The Bony Palate And Otic Region, Andrzej Elzanowski

Postilla

The skull of Hesperornis proves to be neognathous in the majority of diagnostic characters including the presence of the intrapterygoid joint. Most of the remaining characters, including those shared with the paleognaths, are primitive for Neornithes or all birds. In details of the braincase structure, Hesperornis is most similar to Enaliornis, Procellariiformes, Phaethon, and Fregata. A new reconstruction of the palate predicts the presence of the lacrimopalatine (uncinate) and the vomer.

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Agricultural Research Productivity In Pakistan, Qazi Tauqir Azam, Erik A. Bloom, Robert E. Evenson May 1991

Agricultural Research Productivity In Pakistan, Qazi Tauqir Azam, Erik A. Bloom, Robert E. Evenson

Discussion Papers

No abstract provided.

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Yale Nurse, Yale School Of Nursing Jan 1991

Yale Nurse, Yale School Of Nursing

Yale School of Nursing Alumni Newsletters and Magazines

No abstract provided.

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Anatomy And Relationships Of Corosaurus Alcovensis (Diapsida: Sauropterygia) And The Triassic Alcova Limestone Of Wyoming, Glenn William Storrs Jan 1991

Anatomy And Relationships Of Corosaurus Alcovensis (Diapsida: Sauropterygia) And The Triassic Alcova Limestone Of Wyoming, Glenn William Storrs

Bulletin of the Peabody Museum of Natural History

The 'Nothosauria,' a traditional suborder of Triassic marine reptiles, is of interest because of its presumed relationships to both plesiosaurs and primitive diapsid reptiles….

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Separation And Recirculation Of The North Brazil Current, Scott A. Condie Jan 1991

Separation And Recirculation Of The North Brazil Current, Scott A. Condie

Journal of Marine Research

The North Brazil Current separates from the French Guiana coast in the western tropical North Atlantic and a portion of the flow retroflects to form a recirculation zone known as the Demerara Anticyclone. The remainder of the North Brazil Current continues northwestward to join the Guiana Current. This part of the flow may be particularly significant, since it carries a cross-gyre transport of heat and mass from the tropical Atlantic into the subtropical gyre. An extension of the recirculation model of Cessi (1988), in which a quasi-geostrophic flow was driven by potential vorticity anomalies along a boundary, has been used …

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Spectral Time Scales For Mid-Latitude Eddies, William J. Schmitz Jr., James R. Luyten Jan 1991

Spectral Time Scales For Mid-Latitude Eddies, William J. Schmitz Jr., James R. Luyten

Journal of Marine Research

A few hundred current meter records of roughly one to two years' duration are now available from diverse locations in the world's oceans, primarily the North Atlantic. The shape of the spectrum for low-frequency ocean current fluctuations is shown to have a geographical distribution related to the general circulation. In the offshore segment of the Gulf Stream and Kuroshio Extension systems along with their recirculations, and near the Agulhas Current as well, normalized frequency distributions of eddy kinetic energy tend to be comparatively depth-independent and peaked at the mesoscale. However, in the immediate vicinity of current axes or fronts, spectral …

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Optics Of Heterotrophic Nanoflagellates And Ciliates: A Tentative Assessment Of Their Scattering Role In Oceanic Waters Compared To Those Of Bacterial And Algal Cells, André Morel, Yu-Hwan Ahn Jan 1991

Optics Of Heterotrophic Nanoflagellates And Ciliates: A Tentative Assessment Of Their Scattering Role In Oceanic Waters Compared To Those Of Bacterial And Algal Cells, André Morel, Yu-Hwan Ahn

Journal of Marine Research

Heterotrophic nanoflagellates and naked ciliates have been isolated from open sea waters and separately grown by using free living marine bacteria as food. The modal diameters of purified (by differential screening) populations are about 3 and 12.5 μm, respectively. The spectral determination of their absorption and scattering properties have been carried out. By combining these values with the cell number density and size distribution function, simultaneously measured, the efficiency factors for absorption and scattering at the level of individual cells can be derived. From these factors and by using the anomalous diffraction theory, the relative index of refraction can be …

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A Model Of The Diel Vertical Migration Of Zooplankton Based On Euphausiids, Valérie Andersen, Paul Nival Jan 1991

A Model Of The Diel Vertical Migration Of Zooplankton Based On Euphausiids, Valérie Andersen, Paul Nival

Journal of Marine Research

A detailed model of the diel vertical migration of euphausiids, particularly that of Meganyctiphanes norvegica adults in the northwestern Mediterranean Sea, is presented. It simulates the temporal and vertical variation of the euphausiid biomass over the diel cycle in the water column from 0 to 700 m depth. Migration is influenced by two external factors: food (phyto- and zooplankton) and light. Light is assumed to influence migration both by its intensity with the occurrence of an optimal value, and by its relative change in intensity, which affects the ascent or descent of the organisms. The general features of the diel …

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The Accumulation Of Barium By Marine Phytoplankton Grown In Culture, Nicholas S. Fisher, Robert R. L. Guillard, Donald C. Bankston Jan 1991

The Accumulation Of Barium By Marine Phytoplankton Grown In Culture, Nicholas S. Fisher, Robert R. L. Guillard, Donald C. Bankston

Journal of Marine Research

Marine phytoplankton have been implicated as potentially important vectors for the vertical transport of barium in the oceans. To better assess the extent to which phytoplankton can influence the geochemical cycling of barium, its bioconcentration was studied in 21 clones of 19 species of marine phytoplankters belonging to 9 algal classes. Barium levels in the ash ranged from less than 2 μg g–1 for the coccolithophore Emiliania huxleyi and the red alga Porphyridium cruenturn to 589 μg g–1 for the flagellate Tetraselmis levis. Concentrations ≥4000 μg g–1, previously reported for certain samples of diatom ash were …

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Geostrophic Transport Of The South Equatorial Current In The Atlantic, Lothar Stramma Jan 1991

Geostrophic Transport Of The South Equatorial Current In The Atlantic, Lothar Stramma

Journal of Marine Research

Geostrophic transport calculations from historical data of the equatorial South Atlantic are presented for the investigation of the flow field in the South Equatorial Current region. On the basis of water mass distribution, the potential density surface of σ1 = 32.15 kg m–3 is used as a reference for geostrophic shears. This reference surface is located at a depth of 1000 to 1200 m and represents the boundary between the upper branch of the Circumpolar Deep Water and the Upper North Atlantic Deep Water. The southern band of the South Equatorial Current (SSEC) is fed by the Benguela …

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Buoyancy-Driven Circulation As Horizontal Convection On Β-Plane, Nobuo Suginohara, Shigeaki Aoki Jan 1991

Buoyancy-Driven Circulation As Horizontal Convection On Β-Plane, Nobuo Suginohara, Shigeaki Aoki

Journal of Marine Research

The nature of the steady buoyancy-driven circulation is investigated using multi-level numerical models. An ocean which extends over the northern and southern hemispheres is forced by cooling in a confined region and heating in the rest of the ocean through the sea surface. As is already known, the circulation and associated thermal structure strongly depend upon the effect of the vertical diffusivity. This nature of the buoyancy-driven circulation is found in the thermodynamic balance. The vertical diffusion plays an essential role in the whole ocean domain. In counterbalancing the vertical diffusion, the horizontal advection at the deepest levels and the …

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Seasonal Variations Of Surface Dynamic Topography In The Tropical Atlantic: Observational Uncertainties And Model Testing, Christine Duchène, Claude Frankignoul Jan 1991

Seasonal Variations Of Surface Dynamic Topography In The Tropical Atlantic: Observational Uncertainties And Model Testing, Christine Duchène, Claude Frankignoul

Journal of Marine Research

A new analysis of the historical temperature and salinity profiles in the tropical Atlantic is done in order to estimate quantitatively the uncertainties in the climatological seasonal variations of 0/400 db dynamic topography. The uncertainties are described by an error covariance matrix which takes into account aliasing and measurement errors, the effect of data gaps and interpolation, as well as the uncertainty of the T-S method that was used to calculate the dynamic height. The standard deviation of the monthly means is found to range between 2 and 10 dyn cm, depending on the data density and the level of …

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Direct Measurement Of Dissolved Inorganic Nitrogen Exchange And Denitrification In Individual Polychaete (Nereis Virens) Burrows, Erik Kristensen, Mikael Hjorth Jensen, Robert C. Aller Jan 1991

Direct Measurement Of Dissolved Inorganic Nitrogen Exchange And Denitrification In Individual Polychaete (Nereis Virens) Burrows, Erik Kristensen, Mikael Hjorth Jensen, Robert C. Aller

Journal of Marine Research

The burrows of macroinfauna are significant sites of sediment-water nitrogen exchange and associated microbial activity. In this study, the exchange of dissolved inorganic nitrogen (DIN) and nitrogen cycle reaction rates were quantified in individual burrows of the estuarine polychaete Nereis virens. Burrow ventilation rate and DIN (NH4+, NO2−, NO3− and N2O) exchange were determined at 22°C in individual, inhabited burrows with and without the presence of C2H2 (an NH4+ oxidation, N2O reduction block). Ventilation cycles were unaffected by C2H2, …

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Early Diagenesis Of Chlorophyll-A In Long Island Sound Sediments: A Measure Of Carbon Flux And Particle Reworking, Mingyi Sun, Robert C. Aller, Cindy Lee Jan 1991

Early Diagenesis Of Chlorophyll-A In Long Island Sound Sediments: A Measure Of Carbon Flux And Particle Reworking, Mingyi Sun, Robert C. Aller, Cindy Lee

Journal of Marine Research

Sedimentary chlorophyll distributions reflect supply from primary production in overlying waters, transport during sedimentation/bioturbation, and alteration due to decomposition/transformation reactions. In Long Island Sound sediments, seasonal depth profiles of chlorophyll-a (Chl-a) often decreased exponentially within a few centimeters of the sediment-water interface, implying that initial decomposition rates of Chl-a were faster than surface sediment mixing rates. The highest surface sediment concentrations of Chl-a occurred in early spring, shortly after the spring bloom; the lowest concentrations occurred in summer. Chl-a was more concentrated at the shallow station (∼15 m) than at the deeper station (∼40 …

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Bubbles And The Air-Sea Exchange Of Gases In Near-Saturation Conditions, David K. Woolf, S. A. Thorpe Jan 1991

Bubbles And The Air-Sea Exchange Of Gases In Near-Saturation Conditions, David K. Woolf, S. A. Thorpe

Journal of Marine Research

The net air-sea transfer of gases is not simply proportional to the surface gradient of gas concentration as is widely assumed but, when proper account of bubbles is taken, is asymmetrical with a net invasion of gas at 100% saturation. The nitrogen and oxygen saturation levels and the variation of the composition of a bubble during its lifetime affect the transfer of all gases. The net transfer of gases is not a function of the size and depth of the bubbles and the concentration of dissolved gases alone, but is dependent on the composition of the bubbles and thus the …

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Time Scales Of Mesoscale Variability And Their Relationship With Space Scales In The North Atlantic, P. Y. Le Traon Jan 1991

Time Scales Of Mesoscale Variability And Their Relationship With Space Scales In The North Atlantic, P. Y. Le Traon

Journal of Marine Research

A systematic study of characteristic time scales of mesoscale variability over the North Atlantic was done using two years of Geosat data. Time scales are first characterized by 10° latitude by 10° longitude bins. A more detailed description was obtained by globally mapping the Sea Level Anomaly temporal correlation after one cycle (17.05 days). The scales are shortest in areas of high mesoscale activity (Gulf Stream, North Atlantic Current) while relatively long time scales are observed over the Mid-Atlantic Ridge and in the eastern part of the basin. In general, time scales are not proportional to space scales. Propagation velocities …

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Oxic And Anoxic Decomposition Of Tubes From The Burrowing Sea Anemone Ceriantheopsis Americanus: Implications For Bulk Sediment Carbon And Nitrogen Balance, Erik Kristensen, Robert C. Aller, Josephine Y. Aller Jan 1991

Oxic And Anoxic Decomposition Of Tubes From The Burrowing Sea Anemone Ceriantheopsis Americanus: Implications For Bulk Sediment Carbon And Nitrogen Balance, Erik Kristensen, Robert C. Aller, Josephine Y. Aller

Journal of Marine Research

Many marine infaunal animals form organic tube and burrow linings. The role of these materials in organic matter cycling and preservation in sediments is largely unknown. In the case examined here, the infaunal sea anemone, Ceriantheopsis americanus, (a common component of bottom communities along the east coast of North America) forms a leathery, fibrous tube lining 2–3 mm thick, ∼1 cm in diameter, and typically extending 20–30 cm into deposits. Tube fibers (∼2 mm long, 2–5 μm thick) formed from discharged specialized nematocyst cells, ptychocysts, are composed of a silk-like protein copolymer, cerianthin. Tubes incubated under oxic and anoxic conditions …

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Conservative Tracer Study Of Horizontal Sediment Mixing Rates In A Bathyal Basin, California Borderland, Robert A. Wheatcroft Jan 1991

Conservative Tracer Study Of Horizontal Sediment Mixing Rates In A Bathyal Basin, California Borderland, Robert A. Wheatcroft

Journal of Marine Research

In situ tracer (50–125 μm plastic particles) experiments conducted using the DSV Alvin over a two year period in the 1240 m deep Santa Catalina Basin (eastern Pacific) have yielded near-surface (0–1.5 cm) horizontal bioturbation rates of order 1–10 cm2yr–1. Vertical biodiffusivities obtained from the same and similar particulate tracers at the same site are approximately an order of magnitude less. Mixing of near-surface, coarse sediment in Santa Catalina Basin is anisotropic. Deeper within the sediment horizontal bioturbation is not diffusive on a two-year time scale, but would appear to be a form of mixing termed …

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Sources And Transport Of Suspended Calcites In Pacific Deep Water, J. C. Brun-Cottan, R. Auger, C. E. Lambert, R. Chesselet Jan 1991

Sources And Transport Of Suspended Calcites In Pacific Deep Water, J. C. Brun-Cottan, R. Auger, C. E. Lambert, R. Chesselet

Journal of Marine Research

Significantly large concentrations of suspended matter, especially calcites, are found at some locations in the Deep Pacific, particularly at the depth of the Pacific Benthic Thermocline. These particle-rich layers cannot be explained by simple classical settling processes nor by resuspension of the underlying sediment. A theoretical approach based on these data, on the hydrodynamic characteristics of the regional circulation and on some known physical and chemical parameters, leads us to postulate two possible mechanisms: the settling of large particles from surface waters and their preferential disaggregation at some specific depth, particularly at the Pacific Benthic Thermocline depth; or alternatively, the …

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Generation And Propagation Of Inertial Waves In The Subtropical Front, Dong-Ping Wang Jan 1991

Generation And Propagation Of Inertial Waves In The Subtropical Front, Dong-Ping Wang

Journal of Marine Research

A primitive-equation numerical model is used to examine the generation and propagation of internal-inertial waves in the Subtropical Front. The mesoscale variability in surface inertial currents is induced by radiation of internal-inertial waves out of the surface layer. On the warm side of the front, surface inertial energy is carried away by normal internal-inertial waves. A deep inertial energy maximum exists at the base of the thermocline where the effective local inertial frequency approaches the planetary inertial frequency. On the cold side of the front, the surface inertial energy is carried away by anomalously low frequency internal waves. A subsurface …

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Modeling Of Internal Tides In Fjords, V. Tverberg, B. Cushman-Roisin, H. Svendsen Jan 1991

Modeling Of Internal Tides In Fjords, V. Tverberg, B. Cushman-Roisin, H. Svendsen

Journal of Marine Research

A previous model for the distribution of internal tides above irregular topography is generalized to include arbitrary stratification and a radiation condition at the open boundary. Thanks to a small amount of dissipation, this model remains valid in the presence of resonant internal tides, leading to intense wave-energy beams. An application to a Norwegian fjord correctly reproduces the observed energy pattern consisting of two beams both originating at the 60-meter deep entrance sill and extending in-fjord, one upward toward the surface, the other downward toward the bottom. After correction for the varying width of the fjord, the observed and modelled …

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