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On The Existence Of An Ei Niño-Type Phenomenon In The Benguela System, L. V. Shannon, A. J. Boyd, G. B. Brundrit, J. Taunton-Clark

Journal of Marine Research

Since the early 1950s, although there have been several warm and cool periods in the Benguela region off southwestern Africa, e.g. the warm event in the southern part of the system during the austral summer of 1982/83, only two events which approximate to an El Niño-type situation have occurred, viz in 1963 and in 1984. During the 1963 event temperatures 2–4°C and salinities 0.1–0.2 × 10⁻³ above normal were recorded in the upper 50 m off Namibia up to at least 150 km offshore. The pressure adjusted sea level during 1963 was on average 4 cm above the …

A Variational Method For Inverting Hydrographic Data, Christine Provost, Rick Salmon

Journal of Marine Research

We present a new method for estimating the three-dimensional field of geostrophic velocity from hydrographic station data. Very simply, we ask for the smoothest velocity field (in the sense of an arbitrarily defined norm) which is consistent with the data and with selected approximate dynamical constraints to within prescribed misfits, which, we will argue, should never be zero. The misfits represent errors in the data and in the approximate dynamical constraints. By varying the misfits relatively to one another, we explore the full envelope of physically plausible estimates of the average geostrophic flow. We illustrate the method by application to …

Rossby Adjustment Over A Step, A. E. Gill, M. K. Davey, E. R. Johnson, P. F. Linden

Journal of Marine Research

The adjustment of a rotating fluid to a geostrophic equilibrium is now a classical problem in the theory of rotating fluids and is associated with the name of Rossby because of his pioneering work in this subject. The case of particular interest here is the one where the fluid is initially at rest but has a discontinuity in surface elevation along a certain line. If the bottom is flat, the adjustment gives rise to a jet flowing along the line of the initial discontinuity, the width of the jet being the Rossby radius of deformation. This paper examines how the …

Yale Medicine : Alumni Bulletin Of The School Of Medicine, Fall 1985- Summer 1988, Yale University. School Of Medicine

Yale Medicine Magazine - alumni bulletin and magazine

This volume contains Yale medicine: alumni bulletin of the School of Medicine, v.20 (Fall 1985) through v.22 (Summer 1988). Prepared in cooperation with the alumni and development offices at the School of Medicine. Earlier volumes are called Yale School of Medicine alumni bulletins, dating from v.1 (1953) through v.13 (1965).

Digitized with funding from the Arcadia fund, 2017.

Schooling, Information And Non-Market Productivity: Contraceptive Use And Its Effectiveness, Mark Rosenzweig, T. Paul Schultz

Discussion Papers

No abstract provided.

School Expenditures And Enrollments, 1960-1980: The Effects Of Income, Price And Population Growth, T. Paul Schultz

Discussion Papers

No abstract provided.

Estuarine Mean Flow Estimation Revisited: Application To The St. Lawrence Estuary, V. G. Koutitonsky, M. I. El-Sabh

Journal of Marine Research

Mean value estimate errors for estuarine (and oceanic) parameters which exhibit serial correlation and nonstationarity over a finite record length are discussed. It is shown that when trends are nonlinear over the record length, the mean value estimate error does not decrease with time. Instead, it goes through a minimum and then increases again. An optimal averaging time over which the mean estimate error is minimum is presented. The mean circulation in the lower St. Lawrence estuary is described over a record length of 78.5 days in 1979. Standard, bias, and rms errors in mean value estimates are discussed, and …

Average Velocity And Transport Of The Gulf Stream Near 55w, P. L. Richardson

Journal of Marine Research

Long-term current measurements made with surface drifters, SOFAR floats at 700 m and 2000 m, and current meters at 4000 m have been combined to produce for the first time a vertical section of directly measured average zonal currents in and adjacent to the Gulf Stream. The results from the different data sets are remarkably consistent in showing three vertically coherent zonal jets—the Gulf Stream and two flanking countercurrents. The consistency in location, velocity and transport (per unit width) of these currents supports the conclusion that these are real features of the long-term average velocity field. The current jets coincide …

Evidence Of A Double-Cell Subtropical Gyre In The South Atlantic Ocean, Mizuki Tsuchiya

Journal of Marine Research

A map of the sea-surface geopotential anomaly relative to 10 MPa (1000 dbar) suggests that the subtropical gyre in the South Atlantic contains two high cells centered at about 22S and 32S just off the coast of South America. The two cells mayor may not be connected to each other by a narrow band of high geopotential anomaly along the western boundary. This circulation pattern is associated with a general poleward-deepening trend of the isanosteres below 300 m and a reversed trend in the shallower layer. The reversed trend of the isanosteres is particularly pronounced near 25S. This pattern is …

Spatial Patterns In Temperature And Chlorophyll On Nantucket Shoals From Airborne Remote Sensing Data, May 7-9, 1981, Janet W. Campbell, Wayne E. Esaias

Journal of Marine Research

Spatial patterns in 4 aerial mappings of temperature and chlorophyll over Nantucket Shoals were analyzed using a variety of statistical techniques. The goal was to determine whether statistical methods could provide insight concerning phytoplankton dynamics on the Shoals. Statistical techniques included a covariance analysis of large scale trends and a spectral analysis of detrended data. Airborne remote sensors had provided the necessary synopticity in which to observe temporal variability on scales of 0.5–2 days. Maximum correlations between chlorophyll, temperature and depth occurred at nonzero lags, suggesting westward movement of water over the Shoals and a time lag in phytoplankton growth. …

Acoustical Patchiness Of Mesopelagic Micronekton, Charles F. Greenlaw, William G. Pearcy

Journal of Marine Research

Patterns of acoustical scattering in both depth and horizontal extent were analyzed to estimate the spatial and temporal scales of variability in biomass of mesopelagic sound scatterers, principally micronekton. The patterns observed included extensive layers of low and nearly uniform scattering strength and distinct three-dimensional patches of stronger scattering. These patches dispersed vertically at night after diel migration of a portion of the scatterers, but reassembled quite accurately the following day. Analysis of variance spectra for average acoustical scattering profiles within a patch suggest that micro-patches, with dimensions on the order of 15 m vertically by 1 km horizontally, are …

Dispersal Of Meiofauna In A Turbulent Tidal Creek, M. A. Palmer, G. Gust

Journal of Marine Research

Traditionally meiofauna have been viewed as strictly infaunal organisms adapted for life between sediment grains. Recent evidence has shown that marine meiofauna also occur in the water column. A set of field experiments investigated processes controlling the abundance of meiofauna in the water column. The transport of meiofauna in a tidal creek was identified to be primarily a passive process resulting from mechanical removal due to current scour. Drifting meiofauna included interstitial, burrowing, and epibenthic species. Copepods, foraminiferans, and juvenile bivalves were suspended in greatest numbers relative to their sediment abundances. Suspension of meiofauna was greatest for species residing in …

Computer Simulations Of The Fraser River Plume, Louise Royer, W. J. Emery

Journal of Marine Research

Instruments sampling the engine cooling water on two B.C. ferries were used to monitor the temporal and spatial variations of the Fraser River Plume, in the central Strait of Georgia (British Columbia, Canada) for nearly two years. Travelling along two different routes north and south of the river mouth, each ferry provided eight horizontal near-surface salinity transects per day. From each transect, the arithmetic average salinity along the section (denoted southern or northern section average salinity) was extracted, formulated as a time series of hourly or daily values and then compared to equivalent computer simulated series.A numerical model, previously developed …

Some Physical Factors Affecting Ecosystems, Patrice Klein, John H. Steele

Journal of Marine Research

The response of a simple pelagic ecosystem is investigated in a domain with zero, one- and two-dimensional descriptions of the physical processes. Assuming complete mixing, internal recycling and external exchange of nutrients and their biological products are not additive in terms of the rate of primary production. In a one-dimensional system, advection without diffusion leads to low values of primary production. With two horizontal dimensions, cross diffusion at the boundary gives higher values of production. The consequences for higher trophic levels are described.

Minipellets: A New And Abundant Size Class Of Marine Fecal Pellets, Marcia M. Gowing, Mary W. Silver

Journal of Marine Research

Minipellets, fecal pellets from 3 to 50 μm in diameter, were found on detritus collected by a particle interceptor trap array in the upper 2000 m of the eastern tropical Pacific. The fluxes of minipellets reached 5 × 10⁶ m⁻² day⁻¹, and exceeded fluxes of larger (>50 μm diameter) fecal pellets by 3 orders of magnitude. Carbon flux of minipellets was 11–49% that of larger pellets; however, carbon flux of ultrastructurally intact cells (microalgae and bacteria) in minipellets was equal to that of intact cells in the larger pellets. Minipellets also occurred in …

Flow Disruption By An Animal-Tube Mimic Affects Sediment Bacterial Colonization, James E. Eckman

Journal of Marine Research

Simple flume experiments demonstrate that local flow perturbations by a protruding animal-tube mimic can cause a significant increase in bacterial colonization at the sediment-seawater interface. The occurrence and extent of this increase depend on properties of the viscous sublayer adjoining the bed—specifically, its spatial and temporal continuity, and its thickness relative to tube height. In the field homologous tube effects on bacterial colonization and abundances are likely to be common. These effects are postulated to be important to larval recruitment, community composition, the nutrition of deposit feeders, and sediment dynamics.

The Role Of Double Diffusive Interleaving In Mesoscale Dynamics: An Hypothesis, Eric S. Posmentier, A. D. Kirwan Jr.

Journal of Marine Research

It is hypothesized that double diffusive interleaving can act to enhance the temperature, salinity and buoyancy signatures of some mesoscale structures. The hypothesis is founded on theoretical results showing that the fluxes produced by double diffusive interleaving can have counter-gradient components, and on the observations that isolated mesoscale rings have a long lifetime and that there is intense interleaving in the frontal zone typically surrounding the ring. Quantitative examples for a warm and a cold core ring demonstrate the feasibility of the hypothesis. Some suggestions are given for extending the hypothesis to include other mesoscale features. Also theoretical investigations and …

Analyses Of The Settling Velocities Of Fecal Pellets From The Subtidal Polychaete Amphicteis Scaphobranchiata, Paul D. Komar, Gary L. Taghon

Journal of Marine Research

Measured settling velocities of fecal pellets produced by Amphicteis scaphobranchiata, a deposit-feeding subtidal polychaete worm, are analyzed to determine the effects of pellet shapes and to arrive at improved formulae for predicting settling rates of fecal pellets in general. Drag coefficients calculated from the measured settling velocities and pellet densities decrease with increasing Reynolds numbers, the trend roughly paralleling the drag-coefficient curve for spheres but having higher values due to the nonspherical shapes of the pellets. No clear dependence could be found on the pellet shapes, however, when the shape is expressed as pellet elongation (length/width). Comparisons are also made …

Tidal Rectification And Frontal Circulation On The Sides Of Georges Bank, John W. Loder, Daniel G. Wright

Journal of Marine Research

Using Wright and Loder's (l985a,b) depth-dependent tidal rectification model and Garrett and Loder's (1981) diagnostic frontal circulation model, predictions of the residual circulation associated with the topographic rectification of tidal currents and the summertime density field on the northwestern and open ocean sides of Georges Bank are made and compared with observations. In general, the estimates of both wintertime and summertime along-isobath currents are in qualitative agreement with observations, but the agreement between predicted and observed cross-isobath currents is poor. The circulation associated with tidal rectification is primarily along isobaths in an anticyclonic sense around the Bank at all depths. …

Effects Of The Marine Deposit-Feeders Heteromastus Filiformis (Polychaeta), Macoma Balthica (Bivalvia), And Tellina Texana (Bivalvia) On Averaged Sedimentary Solute Transport, Reaction Rates, And Microbial Distributions, Robert C. Aller, Josephine Y. Yingst

Journal of Marine Research

Experimental studies of the deposit-feeders Heteromastus flliformis, Tellina texana, and Macoma balthica demonstrate that, at natural population abundances, each species has major effects on sediment overlying water solute transport, bulk sediment reaction rates, and microbial distributions. Using Cl⁻ as a conservative tracer, one-dimensional transport models show that the effective diffusion coefficient, D_e, in the presence of these macrofauna is ∼2–5× the molecular diffusion value in the upper 8–12 cm of sediment. In general, the exact value of D_e is time dependent as shown by time-course experiments with Heteromastus and by comparison of one-dimensional model predictions with …

Factors Affecting The Distribution Of The Introduced Bivalve, Mercenaria Mercenaria, In A California Lagoon—The Importance Of Bioturbation, Richard C. Murphy

Journal of Marine Research

Quantitative surveys of the Colorado Lagoon and Marine Stadium (Long Beach, California, USA) indicated that the bivalve communities in the Lagoon and in the Stadium were dramatically different, even though water exchanged freely between the two systems for most of the year. In the Lagoon the mean total bivalve density was 143 · m⁻² with a density of the introduced clam, Mercenaria mercenaria, of 78 · m⁻². In the Stadium the mean total clam density was 57 · m⁻² and M. mercenaria was absent. In the Lagoon, bivalve populations were dominated by suspension-feeders, while in the …

Biological Observations In The Marginal Ice Zone Of The East Greenland Sea, Sharon L. Smith, Walker O. Smith, Louis A. Codispoti, David L. Wilson

Journal of Marine Research

The distribution of nutrients, phytoplankton and zooplankton was investigated during summer, 1983 in the marginal ice zone of the East Greenland Sea. Nutrient levels, especially inorganic nitrogen, were extremely low, and probably limited the growth of phytoplankton during this period. An ammonium maximum at the base of the euphotic zone, generally around 50 m, was found repeatedly and appeared to be controlled by active nitrogen regeneration and decreased ammonium uptake at low light levels. Chlorophyll a levels were elevated at the ice-edge, but were even higher in an area influenced by an eddy. Species of zooplankton were accurate indicators of …

Large Scale Pattern Of Recruitment By The Labrid, Semicossyphus Pulcher: Causes And Implications, Robert K. Cowen

Journal of Marine Research

The pattern of recruitment of sheephead, Semicossyphus pulcher, is described throughout a major portion of its range over a period of 7–9 years. The relative recruitment success was determined using both field transects and age-structure data. The observed pattern of recruitment was compared to both spatial and year-to-year variations in the current regime within the region using both average flow data (CalCOFI data base) and satellite imagery. It was found that in areas with larval sources to the north and south, recruitment occurred consistently from year-to-year. However, in areas where there was no larval sources "upstream" of the typical current …

Wind-Driven Mid-Ocean Baroclinic Gyres Over Topography: A Circulation Equation Extending The Sverdrup Relation, R. A. De Szoeke

Journal of Marine Research

What is the circulation driven by wind stress in a stratified ocean above topography? This question was answered by Sverdrup (1947) for vertically integrated transport over flat topography only. By applying the ideas and methods of Rhines and Young (1982a,b), a modified form of the Sverdrup transport relation can be derived for the case of stratification and topography in certain circumstances. This circulation equation is, in quasigeostrophic form,J(Ψ, βy + χf₀h′_T/H) = − χf₀⁻¹gAH J(βy, h′_T) + z · ∇xτ/ …

Annual Cycles Of Nutrients And Chlorophyll In Narragansett Bay, Rhode Island, Michael E. Q. Pilson

Journal of Marine Research

Nutrient concentrations in Narragansett Bay change in a regular way through the seasons, so that characteristic and well defined cycles are observed, but are different for each nutrient. The cyclic changes are not explainable by processes in the water column alone, nor by advection, even though the replacement time of water in the bay is only 10–40 days. It appears possible to incorporate much of the cycling activity in 13-m³ microcosms, so these must include the dominating features of the complex biogeochemical processes involved. Observations in the microcosms suggest that the processes maintaining the annual cycles are sufficiently strong …

Coupling Of The Gulf Of California To Large-Scale Interannual Climatic Variability, Tim R. Baumgartner, Niels C. Christensen Jr.

Journal of Marine Research

The source of interannual changes in the ocean climate of the Gulf of California, indicated by sea level and shore temperature anomalies, is determined by comparison with large-scale circulation in the Pacific Ocean and atmosphere. Independent modes of variability in the large-scale circulation are defined by empirical orthogonal function analysis of eight time series representing the principle ocean currents and surface wind systems. Interannual ocean climate in the Gulf of California is related only to the equatorial mode of variability commonly known as the El Niño/Southern Oscillation. There is no discernible relationship between the Gulf and independent modes of variability …

Spectral "Fingerprinting" Of Phytoplankton Populations By Two-Dimensional Fluorescence And Fourier-Transform-Based Pattern Recognition, P. B. Oldham, E. J. Zillioux, I. M. Warner

Journal of Marine Research

The selectivity of fluorescence spectroscopy is exploited for the characterization of marine algae. Two-dimensional, digital images of in vivo fluorescence intensity versus excitation and emission wavelengths, called excitation-emission matrices (EEMs), are used as spectral "fingerprints" for marine phytoplankton populations. Fourier-transform-based pattern recognition is described along with its inherent strengths and weaknesses for the analysis of natural populations. The EEMs of unknown algae are compared to a library of standard EEMs representing 23 algal species and 6 classes with better than 80% accuracy. The EEMs acquired under different physiological conditions are used in determining pattern recognition reliability. The potential for fingerprinting …

Spectral Observations Of Pigment Fluorescence In Intermediate Depth Waters Of The North Pacific, William W. Broenkow, Alan J. Lewitus, Mark A. Yarbrough

Journal of Marine Research

Vertical profiles at three stations off the California coast showed spectral differences between fluorescence at the primary fluorescence maxima (near 100 m) and the deeper maximum (near 800 m). Two broad-band excitation and several narrow or high-pass emission filters were used with an in situ fluorometer to 1500 m. Interpretation of these data suggests: (1) chlorophyll a was found throughout the water column, with intermediate depth fluorescence about one-third the intensity of that in the primary maximum; (2) phycobilin fluorescence was stronger at intermediate depths than near the surface; and (3) a pigment which fluoresces beyond 700 nm was also …

The Role Of Bacteria In The Turnover Of Organic Carbon In Deep-Sea Sediments, Gilbert T. Rowe, Jody W. Deming

Journal of Marine Research

The cycling of organic carbon in the deep sea was inferred from measurements of sediment trap and box core samples taken on the Biscay and Demerara abyssal plains of the North Atlantic. Of the input of organic carbon to the bottom, less than 10% was buried, i.e., not consumed biologically. Based on laboratory measurements of bacterial activity in the sediment samples, incubated under in situ temperature and pressure, it was possible to attribute at least 13 to 30% of the total inferred biological consumption of organic carbon to microbial utilization. The complementarity of results from these biochemical and microbiological measurements …

Interstitial Water Iodine Enrichments In Sediments From The Eastern Pacific, S. J. Wakefield, H. Elderfield

Journal of Marine Research

The vertical distribution of iodine has been examined in interstitial waters of sediment cores from the Peru Basin, Bauer Basin, Guatemala Basin and the East Pacific Rise and the sediments have been analyzed for iodine and organic carbon. Interstitial water profiles show a strong enrichment of iodine at the sediment surface relative to overlying sea water. This enrichment is much greater than would have been expected had all the iodine originated solely from the breakdown of newly sedimented plankton. This implies recycling of iodine in the region of the water-sediment interface with most of the upward diffusing iodine being rescavenged …