Froneman, Pierre William, Pakhomov, E A, Meaton, V

Surface chlorophyll-a (chl-a) concentrations, microphytoplankton (>20 μm) species composition and distribution along a repeat transect between Cape Town and the Prince Edward Islands were investigated in early austral autumn (April/May) 1996. Samples were collected at approximately 30 nautical mile intervals for the analysis of size-fractionated chl-a and the identification and enumeration of microphytoplankton species. Peaks in total chl-a (>1 μg 1 [superscript -1]) were recorded at the Subtrop...

Cedras, Riaan Brinley

Philosophiae Doctor - PhD (Biodiversity and Conservation Biology) / The primary objective of this study was to investigate patterns in diversity, abundance, distribution and community structure of epi-pelagic copepods across the South West Indian Ocean Ridge (SWIOR). A survey was conducted across the SWIOR at two off-ridge and five seamount stations between 26.94 oS to 41.48 oS in November and December 2009. Copepod species richness and abundance was compared at vertical and horizontal scales da...

Reid, Kirrin Gail

Eddies within oceans act as vehicles, transporting smaller bodies of water, with certain oceanographic characteristics, from one place to another within a larger body of water. The South West Indian Ridge [SWIR] is a topographically complex bathymetric feature which amplifies the production of mesoscale eddies in and around the Antarctic Circumpolar Current [ACC]. Within the Southern Ocean [SO], a section of this ridge - the Andrew Bain Fracture Zone [ABFZ] - has been found to be the starting li...

Annasawmy, Pavanee

Inlcudes bibliographical references / Micronekton fauna was investigated as part of a multi-disciplinary research project carried out in two different bioregions of the South West Indian Ocean: the East African Coastal Province (EAFR) and the Indian South Subtropical Gyre (ISSG). Food web structure was addressed using stable isotopes. Since particulate organic matter had high δ 15 N values in the ISSG province, copepods were chosen as baseline in trophic level estimations. Feeding regime and ...

Lennartsson, Linda

In this thesis a case of advection fog over the Baltic Sea is studied. The period examined is from June 5th to 7th 1995. Data is taken from the instrumented mast, situated on the island Östergarnsholm, a small and flat island without trees outside of Gotland. From the measurements among others the heat flux, relative humidity and temperature are analyzed. In the evening June 5th 1995 the fog is advected in over Östergarnsholm. This can both be seen from the increasing relative humidity and the d...

O'Rourke, Shannon Laraine

This thesis explores conceptions and experiences of motherhood in Ocean View, South Africa through the investigation of a maternal and child health intervention. The Moms and Tots support programme seeks to provide mothers with health education and supportive social networks to improve maternal and child health in a resource-poor context. Based on data collected from participant observation and interviews, three major themes have emerged from the research: the framing of Ocean View and its resid...

Ingersoll, Jim L.

International Telemetering Conference Proceedings / October 13-15, 1981 / Bahia Hotel, San Diego, California / The Mobile Sea Range (MSR) is a set of portable instrumentation designed to allow Fleet Commanders the flexibility to exercise their forces under realistic conditions in an open ocean environment while providing for safety, exercise control, and accurate data collection for reconstruction and analysis. This instrumentation includes targets which require little or no ground control; ...

Attar, Armaghan

Sediment samples were collected during three Ocean Network Canada expeditions to three hydrothermal vent fields at the Endeavour segment of the Juan de Fuca Ridge. The sediments were collected at variable distances (≤ 1340 m) from the vents fields by push core and, in some cases, by suction sampling from base of a chimney structure. The geochemistry of the sediments was investigated in order to understand their formation and the mass fluxes associated with these hydrothermal systems. Qualitative...

Fernández Aymerich, Ismael

There is a lack on ocean dynamics understanding, and that lead oceanographers to the need of acquiring more reliable data to study ocean characteristics. Oceanographic measurements are difficult and expensive but essential for effective study oceanic and atmospheric systems. Despite rapid advances in ocean sampling capabilities, the number of disciplinary variables that are necessary to solve oceanographic problems are large. In addition, the time scales of important processes span over ten orde...

Little, Hazel Jean

Phytoplankton in the Sub-Antarctic Southern Ocean have a distinct seasonal cycle, which is highly variable in both space and time. The seasonal and spatial distribution of chlorophyll can be attributed to the complex nature of the physical and biogeochemical factors controlling phytoplankton production. Studies show that high-resolution sampling is required to understand variability in phytoplankton distribution and primary production. In this study, high-resolution glider data sampled in the At...

Lieke, Kirsten Inga

During the Saharan Mineral Dust Experiment (SAMUM) 2008 field campaign, particles with geometric diameters between approximately 0.1 to 25 µm were collected on board of the Falcon sampling aircraft of the Deutsches Zentrum für Luft- und Raumfahrt (DLR, German Aerospace Centre). To investigate the spatial and vertical distribution of aerosol in the Cape Verde region, sampling was performed along the West African coastline and in the Cape Verde region. The chemical composition of these samples was...

Nag, Amitabh, Cummins, Kenneth L.

We examine downward leader characteristics for negative first return strokes, along with estimated first stroke peak currents, for lightning occurring over land and ocean reported by the U. S. National Lightning Detection Network (NLDN). For the first time, to the best of our knowledge, we report independent evidence that supports the observations by lightning locating systems of higher first stroke peak currents for lightning occurring over ocean than land. We analyzed lightning occurring in fi...

Devlin, Adam Thomas

<p> Ocean tides worldwide have exhibited secular changes in the past century, simultaneous with a global secular rise in mean sea level (MSL). The combination of these two factors contributes to higher water levels, and may increase threats to coastal regions and populations over the next century. Equally as important as these long-term changes are the short-term fluctuations in sea levels and tidal properties. These fluctuations may interact to yield locally extreme water level events, espec...

Hallonsten, Simon

The paper studies the degree of engagement in questions of HIV in the local Anglican Church in Ocean View, Cape Town, using a triangulation design combining participant observation, survey results and interviews. Survey results from two other parishes in the Cape Town area and from clergy in the dioceses of Cape Town and False Bay are used to extend the material and to establish wider patterns in an extended case study approach. The findings show that people in the congregation of St Clare of As...

Butterworth, Brian J.

<p> The Southern Ocean is an important part of the global carbon cycle, responsible for roughly half of the carbon dioxide (CO₂) absorbed by the global ocean. The air-sea CO₂ flux (<i>F_c</i>) can be expressed as the product of the water-air CO₂ partial pressure difference (&Delta;pCO₂) and the gas transfer velocity (<i> k</i>), an exchange coefficient which represents the efficiency of gas exchange. Generally, <i>F_c</i> is negativ...

Lguensat, Redouane

Reconstruire des champs géophysiques à partir d'observations bruitées et partielles est un problème classique bien étudié dans la littérature. L'assimilation de données est une méthode populaire pour aborder ce problème, et se fait par l'utilisation de techniques classiques, comme le filtrage de Kalman d’ensemble ou des filtres particulaires qui procèdent à une évaluation online du modèle physique afin de fournir une prévision de l'état. La performance de l'assimilation de données dépend alors f...

Fiddler, David Michael

Dissertation submitted in compliance with the requirements for the Masters Diploma: Mechanical Engineering, Technikon Natal, 1990. / Increasing fuel prices have forced marine engineers and diesel engine manufacturers to look at methods of. reducing fuel consumption without a loss in output power. Engineers are always Investigating the following points: (1) decreasing the specific fuel consumption (2) enabling engines to use worse fuels ... (3) extending part load capability (4) using as m...

abstract: The numerical climate models have provided scientists, policy makers and the general public, crucial information for climate projections since mid-20th century. An international effort to compare and validate the simulations of all major climate models is organized by the Coupled Model Intercomparison Project (CMIP), which has gone through several phases since 1995 with CMIP5 being the state of the art. In parallel, an organized effort to consolidate all observational data in the past ...

Courgeon, Simon

Bien que l’évolution long terme des plateformes carbonates peu profondes ait été le sujet de nombreuses études au cours des dernières décennies, les processus de contrôles associés et les interactions potentielles avec l’activité géodynamiques restent largement discutées. Le Canal du Mozambique, situé entre les marges continentales est-africaines et malgaches, est caractérisé par plusieurs plateformes carbonatées isolées et par des monts sous-marins à toits plats aujourd’hui ennoyés à plusieurs ...

Lange, Louise

The population structure and feeding dynamics of the hyperiid amphipod, Themisto gaudichaudii, was investigated during two cruises of the South African National Antarctic Programme conducted in the Indian sector of the Polar Frontal Zone during austral autumn (April) 2004 and 2005. During the 2004 cruise the frontal features that delimit the PFZ converged to form a single distinctive feature. In 2005, the research cruise was conducted in the vicinity of a cold-core eddy which was spawned from th...

Gurney, Leigh Josephine

The feeding biology of three euphausiid species, Euphausia vallentini (adults and juveniles), E. longirostris and Nematoscelis megalops was investigated during austral autumn (April/May) of 1998 and 1999, in the vicinity of the Prince Edward Islands (Southern Ocean). Data on the abundance and biomass of these species, estimated from bongo net tows, were investigated. Trophic position was assessed using gut contents and stable nitrogen isotope measurements. Feeding rate and daily carbon ration we...

Nascimento, Andreas.

Orientador: Mauro Hugo Mathias / Coorientador: Gerhard Thonhauser / Banca: Edson Cocchieri Botelho / Banca: João Andrade de Carvalho Junior / Banca: José Luis Gonçalves / Banca: Behzad Elahifar / Abstract: Pre-salt basins and their exploration have become more and more frequently mentioned over the years, not just for their potential reserves, but also for the implicit challenges in terms of operations to face in order to make these fields commercially viable. Several research efforts aimed at a...

Lukáč, Danica

The community structure and predation impact of carnivorous macrozooplankton (>2 cm; chaetognaths, medusae, ctenophores and mysids), with particular emphasis on the chaetognaths Eukrohnia hamata and Sagitta gazellae, were investigated during three surveys conducted in late austral summer (April/May) of 2001, 2004 and 2005 in the Polar Frontal Zone in the vicinity of the Prince Edward Islands (46º45’S, 37º50’E), Southern Ocean. The 2001 survey formed part of the Marion Offshore Variability Ecosys...

Danckwerts, Daniel Keith

Global seabird populations have declined by 70%, since 1950, largely in response to human mediated threats. Identifying the pressures that the remaining populations face has therefore become a top priority. Many breeding colonies are now monitored annually, though others have been almost completely neglected. Considerable bias also exists towards higher latitude species, while fewer studies have been conducted on tropical groups. Beyond tracking population sizes, numerous knowledge gaps also exi...

Madzokere, Eugene T.

>Magister Scientiae - MSc / Maize streak disease (MSD), caused by variants of the Maize streak virus (MSV) A strain, is the world's third and Africa’s most important maize foliar disease. Outbreaks of the disease occur frequently and in an erratic fashion across Africa and Islands in the Indian Ocean causing devastating yield losses such that the emergence, resurgence and rapid diffusion of MSV-A variants in this region presents a serious threat to maize production, farmer livelihoods and food s...

Tragin, Margot

La lignée verte (i.e. les plantes) est représentée dans l'océan par les algues appartenant aux Chlorophyta. Celles-ci contribuent en moyenne à 25% des séquences photosynthétiques (Dinoflagellés exclus) retrouvées dans les inventaires moléculaires pan-océanique. Bien que les Chlorophyta jouent un rôle important dans l'écologie de l'océan et nous permettent de comprendre l'histoire évolutive des plantes terrestres, leur diversité et leur distribution dans les eaux marines du globe est peu document...

Goddard, Paul Brent, Goddard, Paul Brent

Sea level rise (SLR) threatens coastal communities, infrastructure, and ecosystems. Worldwide, stakeholders critically depend on SLR projections with the associated uncertainty for risk assessments, decision-making and coastal planning. Recent research suggests that the Antarctic ice sheet mass loss during the 21st century may contribute up to an additional one meter of global SLR by year 2100. While uncertainty still exists, this value would double the ‘likely’ (> 66% probability) range of glob...

Prasanna, K

The thesis presents observations on the CO2 concentration and carbon isotopes in air CO2 (δ13C) to constrain the inter-annual variability of carbon inventory over the Southern Ocean between the years 2011-2013. Based on the observation, the region of CO2 venting was identified over the Southern Ocean. Further, isotopic characterization allowed inferring about the possible sources of CO2 degassing and contribution from the dissolved inorganic carbon (DIC) that exsolved to generate CO2. It is conc...

Conry, Danielle Shanè

Long-lived, top-level predators, such as some marine mammals, serve as important indicators of ecosystem health. Assessing the abundance and habitat use of such marine top predators is essential for the formulation of effective conservation and management actions. There is considerable concern over the viability of small humpback dolphin opulations across a global scale and a number of studies have raised concerns over their vulnerability to extinction. In light of the recent uplisting of Indian...

Nelson, A. D.

<p> This thesis explores the concepts and techniques of observation-model comparisons of the natural variability of the near-surface ocean on three different time scales. The emphasis on natural variability includes removing the all-time trend and seasonality of the data. All analyses used model outputs of the Community Climate System Model version 3.5 (CCSM3.5). </p><p> The first work, <u>An Ensemble Observing System Simulation Experiment of Global Ocean Heat Content Variability,</u> introduc...

Fissel, D. B.

The standard 3-hourly meteorological observations from Ocean Weather Station "Papa" (50N 145W) for the period 1958 to 196 7 are examined. Power spectra of the wind speed, air pressure, air temperature, absolute humidity, and sea temperature are computed. The wind speed spectra from the open ocean environment are compared with those found at ether ocean, coastal and land stations. The seasonal spectra of these quantities averaged over each of the ten years indicate that the character of the activ...

Collins, A. Kathleen

A coupled biophysical model of the Strait of Georgia, British Columbia, Canada has been developed and successfully predicts the timing of the spring phytoplankton bloom. The physical model is a one dimensional vertical mixing model that is forced with hourly winds, cloud fraction, air temperature, and humidity, daily hydrographic data, and initial profiles of temperature, salinity, and fluorescence. The physical model uses a K Profile Parameterization of the boundary layer, and includes loc...

Morrison, Donald Anthony

Culture is a dynamic entity that changes and adapts over time. However, as our world grows increasingly interconnected, indigenous cultures throughout the world are being assimilated into a 'global' culture, and losing many of the attributes that keep them unique. For instance, the traditional culture of the Outer Hebrides of Scotland is being squeezed between the need for increased development and modernization, and the desire to remain distinct and separate from the cultures of Britain an...

Li, Jingxuan

This thesis, focusing on the Canadian Arctic Ocean, investigates the cycling of particulate trace metals, and the bioavailability of iron to phytoplankton in this rapidly changing ocean. Full depth profiles of particulate Al, Cd, Pb, P, V, Mn, Fe, Co, Cu, Zn and Ba were determined. Trace elements displayed various vertical distributions. Firstly, some elements had a strong lithogenic component (Al, Fe and V), and were characterized by a maximum at the surface. Indeed, their concentrations strong...

Yu, Xiaoxin

Recently observed ²³⁰Th concentrations in 2007 and 2009 documented very high ²³⁰Th values within the Atlantic layer in the Canada Basin of the Arctic Ocean. Similar levels of high ²³⁰Th had only been previously observed in the Alpha Ridge region, implying that the Alpha Ridge is the potential source of the high ²³⁰Th waters. As the Alpha Ridge is downstream in the classic cyclonic circulation, that circulation is believed to have changed. Motivated by this, a three-dimensional Arctic ²³⁰Th model...

Drost, Helen E.

The recent rapid and unprecedented changes to the physical and biogeochemical properties of the Arctic Ocean have gained worldwide attention. The greater than 50% reduction in sea ice volume below average is of great concern. My thesis investigates the potential effects of a warmer Arctic Ocean upon the indigenous Arctic cod, Boreogadus saida. This fish make up a significant proportion of the lower trophic energy reserve available in Arctic marine systems. Predators rely upon Arctic cod to provi...

Fenwick, Lindsay Alexandra

We collected Arctic Ocean water column samples for methane (CH₄) and nitrous oxide (N₂O) analysis on three separate cruises in the summer and fall of 2015, covering a ~10,000 km transect from the Bering Sea to Baffin Bay. Our sampling program provides a large-scale, three-dimensional view of methane and nitrous oxide concentrations across contrasting hydrographic environments, from the deep oligotrophic waters of the deep Canada Basin and Baffin Bay, to the productive continental shelf regions o...

Wade, Lowell

A study of the mineralogy and major element geochemistry of ferromanganese crusts and nodules from the northeastern equatorial Pacific Ocean involved three inter-related projects: ft) the major element geochemistry of crusts and nodules from two study areas, (2) the development of a selective sequential extraction scheme (SSES) and a differential X-ray diffraction technique (DXRD) for the study of the mineralogy of the deposits, and (3) the application of the SSES and DXRD to a small population ...

Cheung, Henry P. Y.

An 80 km seismic refraction line was recorded on an array of three ocean bottom seismometers located 5 km west of the northern tip of Explorer ridge and parallel to Revere-Dellwood fracture zone on the Pacific plate. One reversed and two split-spread profiles have been obtained. The combined use of rotated SV component and polarization filtered record sections enabled identification and timing of the refracted S-wave on most sections. The travel time - distance relation for both P and S ...

Weaver, Anthony T.

The feasibility of sea surface temperature (SST) data improving the performance of an ocean general circulation model (OGCM) is investigated through a series of idealized numerical experiments. The GFDL Bryan-Cox-Semtner primitive equation model is set-up as an eddy resolving, unforced, flat bottomed channel of uniform depth. 'Observed' SST data taken from a reference ocean established in a control run are continuously assimilated into an 'imperfect' model using a simple 'nudging' scheme based...

Reason, Christopher James Charles

A theoretical study is presented of generation of first mode annual period baroclinic Rossby waves by the observed wind stress curl in the South Atlantic and South West Indian Oceans. The forcing wind field for the area 15 S to 51 S, 45 W to 41 E was obtained from an harmonic analysis at the annual period of the monthly mean wind stress curl values derived from Hellerman and Rosenstein's 1983 data. The annual harmonic of the wind stress curl was then used to drive a linear, reduced gravity mode...

Erdman, Linda Ruth

Seventy-one samples of subalkaline and alkaline basalts from British Columbia and the adjacent Pacific seafloor were analyzed for 33 major, trace and rare earth elements using X-ray flourescence (XRF) and instrumental neutron activation analysis (INAA). These basalts are all less than 22 Ma in age and come from various magmatic belts, each with a distinct, well-known, tectonic setting; (1) Convergent margin (Garibaldi and Pemberton Belts), (2) Back-arc (Chilcotin Basalts), (3) Hotspot (Anahim Vo...

Cousens, Brian Lloyd

Fifty fragments of young, fresh basalts from the Explorer Ridge, Paul Revere Ridge (Fracture Zone), Dellwood Knolls, and the J. Tuzo Wilson Knolls have been analysed for 12 major and minor elements, as well as 11 trace elements, by X-ray fluorescence spectrometry. Rare earth element concentrations in 25 of the samples have been determined by instrumental neutron activation, and Sr⁸⁷/Sr⁸⁶ ratios have been obtained for 11 of the basalts. The Explorer Ridge basalts have major element compositions ...

Au, C.Y. Daniel

The Nootka fault zone is the boundary between the small Explorer and Juan de Fuca plates which lie off western Canada between the America and Pacific plates. To investigate the crustal structure in the region, three refraction lines were shot with explosives and a large airgun into three ocean bottom seismometers (OBS's) each equipped with three-component geophone assemblies. The P and S wave profile data are analysed primarily by synthetic seismogram modelling using the WKBJ algorithm. The inte...

Price, Michael Glyn

A regional survey of the sedimentology, geochemistry and mineralogy of the Pleistocene and Holocene deep-sea sediments from the Juan de Fuca Ridge between 47°00' and 48°15' North latitude and the adjacent Cascadia Plain indicates a mainly terrigenous, turbiditic source for most sediments in the area, with some admixture of biogenic material (mainly planktonic debris) throughout. Small hydrogenous and hydrothermal components may also be present. Sedimentation rates during the Pleistocene of about...

Gilchrist, Alfred William Raymond

The directional spectrum of wind-driven surface waves has been measured under conditions of well-defined fetch in Burrard Inlet, which separates the cities of Vancouver and West Vancouver in British Columbia, Canada, and extends seaward to Howe Sound and Strait of Georgia. This investigation was undertaken to check the predictions of two recent theories concerning the mechanism by which the wind acts on the water surface to produce waves. These theories, one due to Phillips and the other to Mil...

Green, John Marshall

The study was concerned first of all with the distribution pattern at low tide of Oligocottus maculosus Girard and other cottid fishes inhabiting tidepools on the west coast of Vancouver Island, B.C. Five species (O. maculosus, G. remensis, Clinocottus acuticeps, C. einbryum and C. globiceps) have their centers of distribution in the intertidal zone. Seven species (Hemilepidotus hernilepidotus, Artedius lateralis, A. fenestralis, Ascelichthys rhodorus, O. snyderi, Enophrys bison and Leptocottus ...

Garrett, John Frederick

The objectives of this study were to show how far the statistical assumptions usually made when dealing with the theory of continuum nonlinear interactions were relevant to the case of fetch limited wind generated wave fields, and to observe some consequence of the nonlinearity as a check on the other results. The usual assumption, that the first order wave field is composed of Gaussian random wave components stationary in space and time, is shown to require that the real and imaginary parts o...

Pramod, N C

No description available.

Fuentes Guerrero, César

Trigger core 07, is a 53 cm long sediment core that was collected during the Danish-Swedish expedition “Lomonosov Ridge off Greenland 2012” on the slope of the Lomonosov Ridge in the Arctic Ocean at a depth of 2522 m. This part of the world has experienced critical environmental changes during the Quaternary. Ice-sheets have advanced and retreated, and deposited sediments through all the Arctic Ocean. Glacial sediments contain coarser material and are gray, whereas interglacial sediments are bro...