Ogunkoya, Ayodele Gilbert

Phytoplankton is an important component of the oceanic carbon cycle, and deriving a good estimate of its carbon biomass (Cphyto) at ocean scale is difficult due to the lack of automatic sampling procedures. This is particularly difficult in the Southern Ocean, where winter conditions limit the sampling. This study explored the opportunity of using a high resolution data from the glider tracks in the Sub-Antarctic Zone of the Southern Ocean. The data consisted of particulate backscattering and ch...

Monteiro, Pedro M S

Bibliography: leaf 78-83. / Analysis and interpretation was carried out on trace metal samples (Cu,Zn,Cd) collected in the Southern Ocean south of South Africa. The results tentatively show that there is a significant copper flux from interstitial waters of the Weddell - Enderby basins. There is little evidence that these trace metals follow the systematics of nutrients throughout the water column; advection appears to play an important role in determining the vertical distribution of these chem...

Abrams, Ronald Woolf

Includes bibliography. / This study investigated the potential usefulness of aerial seabirds as indicators of the distribution of peculiar oceanic biotopes and prey populations in the African sector of the Southern ocean. The hypothesis examined was that the distribution and abundance of seabirds are non-random and predictable with respect to the availability of prey at the sea-surface. The distribution of seabirds was correlated with prey density, in cases where the appropriate information was ...

Halo, Issufo Ferr?o M?rio

Includes abstract. / Includes bibliographical references (leaves 85-92). / The Mozambique Channel and the region south of Madagascar are dominated by high variability of the oceanic flow due to the ubiquitous presence of mesoscale eddies. The bottom topography of this region has several shallow ridges. The water flowing through the Mozambique Channel propagates southwards predominantly as a train of anti-cyclonic eddies, moving towards the Agulhas Current. South of Madagascar, dipolar vortices r...

Billany, William T B

Includes abstract. / Includes bibliographical references (p. 44-46). / The study found that the meridional positions and gradients of MADT exhibit interannual variability as well as considerable trends over the 15-year time-series. The meridional zones along the Greenwich Meridian also displayed clear trends over the period from June 2002 - November 2007 in integrated SST. The trends suggest a warming and shift in the climate state driving some of the variability in the ACC, which is consistent ...

Bergman, Selwyn

Bibliography: leaves 98-104. / The Southern Benguela has, for various reasons, been a focal point for research particularly in recent years. One of the most notable reasons for this interest can he found in the presence of economically viable fish species and their relationship to the process of upwelling. A numerical model of the entire Southern Benguela Region has previously been set up in order to assist furlher studies in the region. This dissertation presents the use of the model in an inve...

Di Santo, Valentina

A major goal in conservation biology is to understand the effects of short and long term environmental change on organisms. Fishes are the most valuable marine resource, however very little is known about the synergistic effect of current ocean warming and acidification, and the role of body size and local adaptation on their resilience. There is growing evidence that increased environmental temperature correlates with a reduction in ectotherm body size, suggesting a universal response to warm...

Balsama, Joseph J.

Thesis (M.A.)--Boston University

Lewis, Colin A

Bird bones from unconsolidated sediments provide a record of the changing avifauna of St Helena from the Late Glacial, at ~ 14000BP, until the present. Changes in avifauna apparently reflect climatic and associated ecological conditions, as well as the effects of human occupation since the island was discovered in 1502. Introduced mammals decimated birds in the seventeenth century and seven endemic species are now extinct, while seven other species are locally extinct. At least nine species that...

Sithole, Yonela

Expected release date-April 2019

Bronselaer, Benjamin, Winton, Michael, Russell, Joellen, Sabine, Christopher L., Khatiwala, Samar

Previous studies found large biases between individual observational and model estimates of historical ocean anthropogenic carbon uptake. We show that the largest bias between the Coupled Model Intercomparison Project phase 5 (CMIP5) ensemble mean and between two observational estimates of ocean anthropogenic carbon is due to a difference in start date. After adjusting the CMIP5 and observational estimates to the 1791-1995 period, all three carbon uptake estimates agree to within 3Pg of C, about...

Froneman, Pierre William, Ansorge, I J, Richoux, Nicole Bertine, Blake, J, Daly, R, Sterley, J, Mostert, B, Heyns, E, Sheppard, J, Kuyper, B, Hart, N, George, C, Howard, J, Mustafa, E, Pey, F, Lutjeharms, J R E

A detailed hydrographic and biological survey was conducted in the region of the Subtropical Convergence in the Indian sector of the Southern Ocean in April 2007. Hydrographic data revealed that the subsurface expression of the Subtropical Convergence (at 200 m), marked by the 10°C isotherm, appeared to meander considerably between 41°S and 42°15’S. Total surface chlorophyll- a concentration was low and ranged from 0.03 to 0.42 µg l–1 and was always dominated by the pico- (<2 µm) and nano- (2–12...

Pakhomov, E A, Ansorge, I J, Kaehler, S, Vumazonke, Lukhanyiso Unam, Gulekana, K, Bushula, T, Balt, C, Paul, D, Hargey, N, Stewart, H, Chang, N, Furno, L, Mkatshwa, S, Visser, C, Lutjeharms, J R E, Hayes-Foley, P

The Dynamics of Eddy Impacts on Marion’s Ecosystem Study (DEIMEC) programme was begun in 2002 with the aim of understanding the importance of the oceanic, upstream environment to the ecosystem of the Prince Edward Islands. This island group consists of two small volcanic islands and provides many opportunities for studying ecological and evolutionary processes, for monitoring ecological changes in relation to global climate change and for conserving a unique component of the planet’s biological ...

Tsei, Senam Kofi

Numerous Argo floats (approximately 3800 floats) have been deployed in the world's oceans to gather hydrographic and biogeochemical data from the upper 2000 m. However, limited research has been done on the spatial and temporal distribution and potential sampling bias of Argo profiling floats brought on by the effects of bathymetric steering of currents, as well as oceanic features, such as meanders and eddies, that affect their distribution over the global ocean. This study investigates the sam...

Wang, Manman

The upper ocean is host to overlapping vortical and internal waves dynamics over the submesoscales (10-100km), both of which are poorly represented in eddy-resolving ocean models. We analyze upper-ocean (0-200 m) horizontal-wavenumber spectra along Line P in the North Pacific subpolar gyre from shipboard ADCP measurements in February and June (2013-2015), and compare them to spectra from a 1/36th degree numerical simulation output. At scales between 10 and 100 km, the ADCP along-track (Cv) and a...

Li, Wei

Ocean wave energy is considered to be one of the important potential renewable energy resources for sustainable development. Various wave energy converter technologies have been proposed to harvest the energy from ocean waves. This thesis is based on the linear generator wave energy converter developed at Uppsala University. The research in this thesis focuses on the foundation optimization and the power absorption optimization of the wave energy converters and on the wave climate modelling at t...

Eriksson, Carolina

Wave power is currently a hot topic of research, and has shown great potential as a renewable energy source. There have been lot of progress made in developing cost effective Wave Energy Converters (WECs) that can compete with other sources of energy in regard to price and electrical power. Theoretical studies has shown that optimal control can increase the generated power for idealized WECs. This thesis is done in collaboration with CorPower Ocean, and investigates the use of economic Model Pred...

Bolton, Ingrid

This text is presented in conjunction with my exhibition Crossing the Ecoline and is a visual response to changing levels of ocean acidification. My art making is informed by the processes of dispersal and dissolution that occur at the point where the absorption of carbon dioxide takes place between the atmosphere and the ocean. This project is of an interdisciplinary nature and traverses art and science - both technically and through collaboration. By working in close consultation with marine s...

Firth, Robert James

Numerical weather prediction is a computationally expensive task that requires not only the numerical solution to a complex set of non-linear partial differential equations, but also the creation of a parameterization scheme to estimate sub-grid scale phenomenon. The proposed method is an alternative approach to developing a mesoscale meteorological model a modified recurrent convolutional neural network that learns to simulate the solution to these equations. Along with an appropriate time inte...

PUN, IAM-FEI, 潘任飛

碩士 / 國立臺灣師範大學 / 地球科學系 / 93 / Lack of the information on upper-ocean thermal structure is one of the identified major reasons causing unsatisfactory typhoon intensity forecast. Therefore it is critical to study the relationship between upper-ocean thermal structure typhoon intensity change. This study uses a two-layer reduced gravity ocean model (TLM_NWPO), TOPEX/Poseidon and JASON-1 sea surface height anomaly data, TRMM/TMI sea surface temperature data and climatological ocean data estimate uppe...

Wang, Su

We trained a combined deep convolutional neural network to predict seals’ age (3 categories) and gender (2 categories). The entire dataset contains 110 seals with around 489 thousand location records. Most records are continuous and measured in a certain step. We created five convolutional layers for feature representation and established two fully connected structure as age’s and gender’s classifier, respectively. Each classifier consists of three fully connected layers. Treating seals’ latitud...

Coats, S., Smerdon, J. E., Cook, B. I., Seager, R., Cook, E. R., Anchukaitis, K. J.

Multidecadal droughts that occurred during the Medieval Climate Anomaly represent an important target for validating the ability of climate models to adequately characterize drought risk over the near-term future. A prominent hypothesis is that these megadroughts were driven by a centuries-long radiatively forced shift in the mean state of the tropical Pacific Ocean. Here we use a novel combination of spatiotemporal tree ring reconstructions of Northern Hemisphere hydroclimate to infer the atmos...

Kim, Won-Gyu, 1962-

The Hamiltonian of a stably stratified incompressible fluid in an internal water wave in a deep ocean is constructed. Studying the ocean internal wave field with its full dynamics is formidable (or unsolvable) so we consider a test-wave Hamiltonian to study the dynamical and statistical properties of the internal water wave field in a deep ocean. Chaos is present in the internal test-wave dynamics using actual coupling coefficients. Moreover, there exists a certain separatrix net that fills the ...

Yao, Qichao, Brown, Peter M., Liu, Shirong, Rocca, Monique E., Trouet, Valerie, Zheng, Ben, Chen, Haonan, Li, Yinchao, Liu, Duanyang, Wang, Xiaochun

Identification of effects that climate teleconnections, such as El Nino-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and North Atlantic Oscillation (NAO), have on wildfires is difficult because of short and incomplete records in many areas of the world. We developed the first multicentury wildfire chronologies for northeast China from fire-scarred trees. Regional wildfires occurred every 7years from the 1700s to 1947, after which fire suppression policies were implemented. Reg...

Cowen, Steven J.

International Telemetering Conference Proceedings / October 13-15, 1981 / Bahia Hotel, San Diego, California / This paper describes results obtained at the Naval Ocean Systems Center, San Diego, under Independent Exploratory Development funding. The objective was to develop a robust, fully-demountable, high pressure penetrator design suitable for coupling light signals transmitted by optical fiber elements in an undersea cable operated at high ambient hydrostatic pressure into an electronics...

Williams, N. L., Juranek, L. W., Johnson, K. S., Feely, R. A., Riser, S. C., Talley, L. D., Russell, J. L., Sarmiento, J. L., Wanninkhof, R.

Empirical algorithms are developed using high-quality GO-SHIP hydrographic measurements of commonly measured parameters (temperature, salinity, pressure, nitrate, and oxygen) that estimate pH in the Pacific sector of the Southern Ocean. The coefficients of determination, R-2, are 0.98 for pH from nitrate (pH(N)) and 0.97 for pH from oxygen (pH(Ox)) with RMS errors of 0.010 and 0.008, respectively. These algorithms are applied to Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM...

Sharp, Kirk, Thompson, Lorraine Masi

International Telemetering Conference Proceedings / October 30-November 02, 1989 / Town & Country Hotel & Convention Center, San Diego, California / The Naval Ocean Research and Development Activity (NORDA) has adapted the Loral Instrumentation Advanced Decommutation system (ADS 100) as a portable maintenance system for one of its remotely deployable buoy systems. This particular buoy system sends up to 128 channels of amplified sensor data to a centralized A/D for formatting and storage on a hi...

Stenberg, Emma, Östling, Elin

This study's purpose is to provide empirical evidence on how fund companies can reason according to SRI when selecting investment in different Asia and Pacific Ocean companies and describe why they make the selection they do. To fulfil the purpose, a case study has been conducted containing interviews with fund managers and representatives that bare the same knowledge about making and managing fund portfolios. The respondents represented one fund company each and also had knowledge about fund ma...

Rodriguez, J. Alexis P., Fairén, Alberto G., Tanaka, Kenneth L., Zarroca, Mario, Linares, Rogelio, Platz, Thomas, Komatsu, Goro, Miyamoto, Hideaki, Kargel, Jeffrey S., Yan, Jianguo, Gulick, Virginia, Higuchi, Kana, Baker, Victor R., Glines, Natalie

It has been proposed that similar to 3.4 billion years ago an ocean fed by enormous catastrophic floods covered most of the Martian northern lowlands. However, a persistent problem with this hypothesis is the lack of definitive paleoshoreline features. Here, based on geomorphic and thermal image mapping in the circum-Chryse and northwestern Arabia Terra regions of the northern plains, in combination with numerical analyses, we show evidence for two enormous tsunami events possibly triggered by b...

Ohlsson, Alexandra

The aim of this study is to investigate how well the wind stress is described in the regional climate model RCA (Rossby Centre Atmospheric model). The model data is compared with measurements taken at Östergarnsholm, an island located east of Gotland in the Baltic Sea. The investigation covers the period October 1997 to September 2000. Compared with the measurements RCA underestimates the wind speed over ocean in most cases. When the wind speed is studied in monthly mean it was found that the wi...

Harlander, Uwe

In einer kürzlich erschienenen Arbeit haben Greatbatch und Zhang darauf hingewiesen, daß interdekadische Oszillationen in einem Ozean-Becken-Modell gefunden werden können, falls dieses mit festgehaltenen Wärmeflüssen angetrieben wird. Diese Oszillationen haben Ahnlichkeit mit jenen, welche Delworth et al. in einem gekoppelten Ozean-Atmosphären-Modell fanden. In der vorliegenden Arbeit werden Mechanismen verglichen, die in drei einfachen Ozeanmodellen mit festgehaltenen Antrieben zu Schwingungen ...

Vandenberg, Nathan

The Salish Sea is a ecologically important coastal region located on the southwest part of British Columbia. Optical measurements were taken using a set of hyperspectral radiometers, the SAS Solar Tracker developed by Satlantic. This sensor is installed on the Queen of Oak Bay ferry, that runs between Nanaimo and Vancouver, as part of the Ferry Ocean Colour Observation Systems (FOCOS) project. We developed a computer program to process the raw sensor data and generate remote sensing reflec...

Germineaud, Cyril

Dans le Pacifique sud-ouest, le cheminement des eaux depuis la gyre subtropicale vers l'équateur est réalisé via les courants de bord ouest (WBCs), associés à des changements de température ou de quantité d'eau à di?érentes échelles de temps. La mer des Salomon située au sud de la Pa- pouasie Nouvelle-Guinée est considérée comme une région clé pour étudier les WBCs juste avant qu'ils rejoignent l'équateur. Dans le cadre d'une collaboration internationale, deux campagnes en mer ont été réalisées ...

Janssen, David

Zinc (Zn) and cadmium (Cd) have nutrient-type vertical distributions reflecting control driven by biological uptake in surface waters and remineralization of sinking biogenic particles at depth. Both metals show strong correlations with major algal nutrients (Cd with phosphate (PO43-) and Zn with silicic acid (Si)) in the world ocean. Through their roles as micronutrients and toxins to marine phytoplankton, Zn and Cd can influence surface biological community composition. Preserved Zn and Cd rec...

Boodhraj, Kirodh

The sub-Antarctic Zone (SAZ) is a zone of vigorous vertical mixing in the Southern Ocean where it is difficult to obtain data for model validation on the turbulence conditions. In this study, a onedimensional configuration from the Nucleus for the European Modelling of the Ocean (NEMO) model was implemented in order to determine the sensitivity and turbulence response of an idealized SAZ water column. Various turbulence scheme parameterizations that are available for ocean models were tested. Fu...

Robertson Lain, Elisabeth

There is increasing interdisciplinary interest in phytoplankton community dynamics as the growing environmental problems of water quality (particularly eutrophication) and climate change demand attention. This has led to a pressing need for improved biophysical and causal understanding of Phytoplankton Functional Type (PFT) optical signals, in order that satellite radiometry may be used to detect ecologically relevant phytoplankton assemblage changes. This understanding can best be achieved with...

abstract: This thesis research focuses on developing a single-cell gene expression analysis method for marine diatom Thalassiosira pseudonana and constructing a chip level tool to realize the single cell RT-qPCR analysis. This chip will serve as a conceptual foundation for future deployable ocean monitoring systems. T. pseudonana, which is a common surface water microorganism, was detected in the deep ocean as confirmed by phylogenetic and microbial community functional studies. Six-fold copy nu...

abstract: The oceans play an essential role in global biogeochemical cycles and in regulating climate. The biological carbon pump, the photosynthetic fixation of carbon dioxide by phytoplankton and subsequent sequestration of organic carbon into deep water, combined with the physical carbon pump, make the oceans the only long-term net sink for anthropogenic carbon dioxide. A full understanding of the workings of the biological carbon pump requires a knowledge of the role of different taxonomic g...

Vousden, D, Scott, Lucy Elizabeth Powell, Sauer, W H H, Bornman, T G, Ngoile, M, Stapley, J, Lutjeharms, J R E

An ambitious multinational programme, with generous funding for an initial five years, aims to provide understanding of marine resources for the benefit of impoverished island and coastal populations in a much-neglected ocean region.

Kaparulina, E. (Ekaterina)

Abstract In this Ph.D. thesis sediment cores from the central Arctic Ocean, southwestern Barents Sea and sediment exposures from the Kola Peninsula were investigated in order to reveal interactions between the late middle Pleistocene and late Pleistocene Arctic ice sheets, between Marine Isotope Stages 6 and 1 (MIS 6 and MIS 1). One of the main objectives of this work is to establish provenance areas for the sediments studied in the central Arctic, the southwestern (SW) Barents Sea and the Kola...

Wong, Sun, Behrangi, Ali

Differences in gridded precipitation (P), surface evaporation (E), and the resultant surface freshwater exchange (P - E) among different products over the ocean are diagnosed as functions of moisture advection (Q(advt)) and moisture tendency by dynamical convergence (Q(cnvg)). Compared to the GPCP product, the TRMM3B42 product captures higher frequency of precipitation with larger extreme precipitation rates in regimes of deep convection and more light rain detections in regimes of frequent occu...

Semeniuk, David Mathew

Copper (Cu) is an essential micronutrient for phytoplankton, particularly during iron limitation, but can also be toxic at relatively low concentrations. While Cu stoichiometry and metabolic functions in marine phytoplankton have been studied, little is known about the substrates for Cu transport and the Cu nutritional state of indigenous phytoplankton communities. The aim of my thesis was two-fold: investigate the bioavailability of organically bound Cu to laboratory and indigenous phytoplankto...

Chandana, K. R., Bhushan, Ravi, Jull, A. J. T.

Multi-proxy approach for the reconstruction of paleo-redox conditions is attempted on a radiocarbon (C-14) dated sediment core near the equatorial Indian Ocean. Based on the behavior and distribution of redox sensitive and productivity proxies, study demonstrates prevalence of anoxic bottom water conditions during LGM due to poorly ventilated bottom waters augmented by high surface productivity resulting in better preservation of organic carbon (OC). During early Holocene, the equatorial Indian ...

Komacek, Thaddeus D., Abbot, Dorian S.

Terrestrial exoplanets in the canonical habitable zone may have a variety of initial water fractions due to random volatile delivery by planetesimals. If the total planetary water complement is high, the entire surface may be covered in water, forming a "waterworld." On a planet with active tectonics, competing mechanisms act to regulate the abundance of water on the surface by determining the partitioning of water between interior and surface. Here we explore how the incorporation of different ...

Lindkvist, Marcus

The uptake of carbon in the ocean may change with global warming, which can have significant feedback effects on the climate. To investigate the change, a two box ocean model has been used to simulate the temperature and carbon content in the atmosphere, in a shallow and deep layer of the ocean, when doubling the amount of carbon dioxide in the atmosphere. The results were compared with a low-resolution Earth system model called cGENIE, which is a more complex model. The two box ocean model show...

Sha, Yingkai

The Arctic Ocean freshwater plays important roles in regional and global climate. Dissolved Barium and the Oxygen isotope ratio are two tracers that provide key information on the river runoff and the sea-ice melt water as two Arctic Ocean freshwater components. In this research, an offline tracer model was developed with dissolved Barium and Oxygen isotope ratio modules and appropriate boundary conditions were applied to the Arctic Ocean to simulate the spatial and temporal variations of the tw...

Sternsdorff Cisterna, Nicolas Igor

What motivates businesses to voluntarily join an eco-label and pledge to uphold standards over and above those required by the state? The academic literature has generally approached this question by analyzing the economic benefits a business derives from their participation. We can explain their behaviour because they are receiving economic benefits in the form of price premiums, brand equity or market share. The benefits can also come in the form of risk mitigation by designing your own e...

Zedel, Len

This thesis describes a study of near surface ocean processes based on observations made with an instrument incorporating both active and passive acoustical systems. The topics addressed include the organization of bubble clouds by Langmuir circulation, the modulation of ambient sound levels by surface wave action, and the interactions of vortices associated with Langmuir circulation. Observations in a deep ocean environment reveal bubble clouds organized into plumes of 100 m length and widths ...

Scott, Beth Emily

A main concern in fisheries science has been to identify an accurate index of fish abundance. An underlying paradigm in the science has been that the amount of effort (calculated in hours and standardized for boat size) spent fishing was the best variable to be used to account for the variation in catches. The use of the ratio, catch per unit of effort (cpue), assumes that variations in fish abundance are due to human-controlled processes above the ocean's surface. It does not account for variat...

Leaman, Bruce Michael

This study examines the reproductive and population biology of a long-lived (80-y life span) fish, Sebastes alutus (Gilbert). The objectives of the study were (i) to establish whether groups of adult S. alutus delineated by exploitation histories could be objectively identified as separate sub-populations; (ii) to identify the effects of density-independent mortality caused by exploitation, and relate them to predictions of life history theory (iii) to examine the long-term implications of this ...