Physical and geochemical tracer measurements were collected at one oceanographic station (Station A: 72 N 143 W) in the southern Canada Basin from 1989 to 1995, along sections from the Beaufort Shelf to this station in 1993 and 1995, and along a section westward of Banks Island in 1995. These measurements were examined to see how recent events in three upstream Arctic Ocean sub-basins impacted upon Canada Basin waters. Upstream events included Atlantic layer warming, relocation of the Atlantic/Pacific water mass boundary, and increased ventilation of boundary current waters. Early signals of change appeared first in the Canada Basin in 1993 along the continental margin and, by 1995, were evident at Station A in the basin interior and farther downstream. Differences in physical and geochemical properties (nutrients, oxygen, ¹²⁹I and CFCs) were observed throughout much of the water column to depths greater than 1600 m. In particular, the boundary distinguishing Pacific from Atlantic-origin water was found to be shallower and Atlantic-origin water occupied more of the Canada Basin water column. By 1995, Atlantic-origin water in the lower halocline at Station A was found to be colder and more ventilated. Likewise, within the Atlantic layer, Fram Strait Branch (FSB) water was colder, fresher, and more ventilated, and Barents Sea Branch (BSB) water was warmer, fresher, and more ventilated than during previous years. By comparing observations at Station A with eastern Nansen Basin observations, the main source of these changes was traced to dense water outflow from the Barents Sea. Studies indicated that in early 1989 Barents Sea waters were 2°C warmer and that, between 1988 and 1989, a large volume of dense water had left the shelf. These events coincided with an atmospheric shift to increased cyclonic circulation in 1989, a transition unprecedented in its magnitude, geographic reach, and apparent oceanographic impact. The effects of a large outflow of dense Barents Sea water were observed some 5000 km away downstream in the Canada Basin where the BSB component of the Atlantic layer had increased 20% by 1995. / Graduate

No description available.

No description available.

This dissertation explores the uses for data collected at broadband seismic stations to investigate upper mantle structures. In the Barents Sea region, we use seismic waveform modeling on data collected from arrays in Norway and Finland to investigate the nature of the Hales discontinuity in this area. We find that the unusually high velocities required by the move-out of the diffracted first arrival requires a discontinuity below the Moho, which we believe is probably caused by a phase transition from spinel to garnet peridotite. In Chile and Argentina, we use data collected during the Chile Argentina Geophysical Experiment to perform a regional travel time tomography in order to investigate the nature of the mantle above this unusual subduction zone. The northern half of the study area (between 30° and 33°S) is characterized by the central Chilean flat slab segment, where the descending Nazca slab dives to 100 km depth and then flattens, traveling horizontally for hundreds of kilometers before resuming its descent into the mantle. The Nazca plate in the southern half of the study area has a relatively constant dip of about 30°. The southern half exhibits normal arc volcanism roughly above the 100 - 125 km contours of the downgoing slab. The northern half has had no active volcanism in the past 2 Ma, and underwent an eastward displacement of arc volcanism beginning ~10 Ma. The northern half is also remarkable for the basement-cored uplifts of the Sierras Pampeanas. Our study of the upper mantle above the southern half indicates low P wave velocities, low S wave velocities, and high Vp/Vs ratios below the arc, consistent with partial melt. Above the flat slab segment we find low Vp, high Vs, and low Vp/Vs ratios. While the nature of the material responsible for these velocities cannot be uniquely determined, the velocities indicate it must be dry, cold, and depleted. In the transition from flat to normal subduction geometries, we find velocities consistent with frozen asthenosphere, which may have been displaced by the advancing flat slab during the Miocene.

L’étendue hivernale de la banquise en mer de Barents n’a cessé de diminuer, et un certain nombre d’études suggèrent que cette diminution pourrait coïncider avec des hivers très froids en Europe et Asie. L’eau Atlantique (AW) transportée vers la mer de Barents, se réchauffe. En mer de Barents, l’AW se transforme en Barents Sea Water (BSW), plus froide et moins salée. Etudier cette dernière nous permet d’en savoir plus sur l’influence de la saisonnalité de la banquise Arctique sur la stratification et la circulation de l’océan.Tout d’abord, nous utilisons des observations satellites pour localiser le Front Polaire (PF) qui matérialise la limite entre la BSW et l’eau Arctique. Nous établissons que l’étendue de la banquise était indépendante du PF jusqu’au milieu des années 2000, jusqu’à ce que le réchauffement de l’AW commence à limiter l’extension de la banquise hivernale au sud du front. Ensuite, en combinant données satellites et in situ, nous montrons que l’on peut surveiller ‘à distance’ les propriétés de la BSW : les variations de la température de surface de l’océan sont ainsi corrélées à celles du contenu en chaleur de la mer de Barents qui, associées à celles de la hauteur stérique, permettent également d’estimer son contenu en eau douce.Pour finir, nous utilisons un modèle à haute résolution pour calculer les bilans de volume, transport et flux des masses d’eau. Le volume de la BSW atteint un minimum en 1990 et 2004 : l’étendue de glace de mer hivernale ayant fondue l’été suivant était alors conséquente, résultant notamment d’une masse d’AW plus froide. L’événement de 2004 a permis une entrée massive d’AW, de plus en plus chaude, dans la mer de Barents. / Winter sea ice has declined in the Barents Sea and there is growing evidence that the low sea ice here coincides with cold, winter surface air temperature in Europe and Asia. Atlantic Water (AW) transported into the Barents Sea is warming and its temperature variability is correlated with variability in sea ice extent. As AW extends into the Barents Sea it is modified into a cooler, fresher water mass called BarentsSea Water (BSW). There are limited observations of BSW despite its importance in the Arctic Ocean system, leading to the question, how does the seasonal sea ice impact ocean stratification and mean flow?First, satellite observations are used to find the Polar Front, a water mass boundary between BSW and fresher Arctic Water to the north. The sea ice extent was found to be independent of the Polar Front until the mid-2000s when warming AW prevented the extension of winter sea ice south of the front.Second, by combining satellite and in situ data, it is shown that sea surface temperature can approximate heat content in the Barents Sea. Using heat content with satellite steric height, freshwater content can also be estimated, showing the potential for remote monitoring of BSW properties.Third, a high-resolution model is used to calculate the volume, transport and flux budgets within the AW and BSW domain south of the Polar Front. The model shows BSW volume minimum years in 1990 and2004. Both events were preceded by extensive winter sea ice and substantial summer sea ice melt, a result of preceding, cool AW. The event in 2004 was more extreme and allowed warming AW a greater volume in the Barents Sea.

This study presents a conceptual and theoretical framework for peace building and restorative action in the Arctic Barents Region where the Sami of the Scandinavian region live. Based on Johan Galtung´s theory of peace, the study approaches the issue of peace building and restorative action by considering the history of colonialism and the meaningful lessons drawn from it as a pedagogic field and with human development as the goal. Central to this imperative is the issue of cognitive justice. The study explores the peace potential in including indigenous knowledge systems and the ethics embedded in them in the developmental discourse going forward. The word “ethics” is explored within this imperative, with the study arguing that developing an ethical rationality compatible with the goal of peace and human development in this context is not primarily about the mastering of rules and principles or adjusting to modernity´s mores but about something far more fundamental, namely, the work of re-establishing the esteem for the Other – the very fundamental condition of human community – in a context in which respect for the intrinsic value, dignity and individual autonomy of others and therein their active participation in the world, are under severe strain. The remote space that is devoted to this fundamental relation with the Other in today's leading moral-philosophical discourse thus stresses the need to open up new “cognitive spaces” so that wisdom may emanate more freely from non-western traditions in order to expand the range of ethical rationality. This argument is supported by hermeneutical theory, especially that of Gadamer, the core of which is that communicative acknowledgement of the Other must be based exclusively on the Other’s premises, where the world of the Other is prioritised as the key for understanding oneself. The arbitrative lesson of hermeneutics is that true comprehension is not possible by evading the Other. It is at this point that Levinas’ analysis of the “face” becomes central: The Other is experienced “face-to-face”, meaning “without horizons” and refers to an experience before my will and freedom and which implies that I transcend myself when I acknowledge my responsibility for my Self as the responsibility for the Other. The study concludes that building peace by restoring indigenous systems of trust and hospitality is vital in any attempt to cope with current difficulties and for moving forward in a restorative paradigm. / Educational Studies / D. Ed. (Philosophy of Education)

<p>Ekosystembaserad förvaltning bygger på en helhetlig syn på ekosystemen och dess förhållande till mänsklig aktivitet. Förvaltningsplanen för Barents hav utanför Norge är ett de längst framskridna försöken till implementering av denna förvaltningsmodell. Lång väg återstår dock för att uppnå de målsättningar som satts och särskilt gäller detta miljömålet för biologisk mångfald. Trots att fiskeri utpekats som den största påverkningsfaktorn på biologisk mångfald har det varit lite fokus på fiskeriernas negativa konsekvenser i arbetet med förvaltningsplanen. Den här uppsatsen försöker ge en bild av hur personer som jobbar inom förvaltningen ser på värdet med förvaltningsplanen, hur de uppfattar dess brister, och just varför de tror att fiskeriet negativa konsekvenser fått liten uppmärksamhet.</p><p>Helhetlighet och tvärsektoriellt samarbete kunde konkluderas som de främsta värdena med förvaltningsplanen. Organisationsproblem, konservatism och maktkamper ansågs dock skapa problem för implementering och samarbete över sektorerna, bland annat genom genom dålig kommunikation mellan utredningsgrupper och den implementerande organisationen. Konservatism och maktkamp uttrycktes i form av en ovillighet från andra att samarbeta över sektorerna, att bryta det sektoriella tankesättet, och en vilja att värna om sin maktsfär.  Strukturella problem lyftes även fram som en av de bakomliggande anledninganar till att fiskeriernas negativa effekter inte fått mer fokus. Starkt kulturellt fäste, fokus på petroleumsverksamhet och dålig kunskapsförmedling var andra faktorer som togs upp. </p> / <p>Ecosystem based management is a management approach that seeks to integrate ecological, social and economic goals. The Norwegian management plan for the Barents Sea is one of the most advanced attempts to ecosystem based management. There is, however, still a long way to go to achieve the goals that have been set. This is especially true for the environmental objective of biodiversity. Even though fishing activity has been pointed out as one of the main reasons for biodiversity loss, little attention has been drawn to this fact. This paper therefore tries to give the answer to the questions of how people working within the management perceive the plan; the core values of it, its flaws, and why they beleave that the negative consequenses of fisheries have been out of focus.</p><p> </p><p>The holistic viewpoint and the cooperation between the various sectors were the most emphazised values of the management plan. Organizational problems, conservatism, and power struggles were regarded as the main problems in trying to reach these goals. Lack of communication between  implementing bodies and investigating bodies was one example of this. Conservatism and power struggles were described as unwillingnes among individuals to adopt to the new intersectoral structures, and a wish to safeguard ones own power. The reason why the negative consequenses of fisheries have been out of focus, was also blamed on structural problems to a large extent. Other contributing factors were also the strong cultural role fisheries play in the norweigan society, the political focus on petroleum activity, and an insufficient spread of knowledge.</p>

Ekosystembaserad förvaltning bygger på en helhetlig syn på ekosystemen och dess förhållande till mänsklig aktivitet. Förvaltningsplanen för Barents hav utanför Norge är ett de längst framskridna försöken till implementering av denna förvaltningsmodell. Lång väg återstår dock för att uppnå de målsättningar som satts och särskilt gäller detta miljömålet för biologisk mångfald. Trots att fiskeri utpekats som den största påverkningsfaktorn på biologisk mångfald har det varit lite fokus på fiskeriernas negativa konsekvenser i arbetet med förvaltningsplanen. Den här uppsatsen försöker ge en bild av hur personer som jobbar inom förvaltningen ser på värdet med förvaltningsplanen, hur de uppfattar dess brister, och just varför de tror att fiskeriet negativa konsekvenser fått liten uppmärksamhet. Helhetlighet och tvärsektoriellt samarbete kunde konkluderas som de främsta värdena med förvaltningsplanen. Organisationsproblem, konservatism och maktkamper ansågs dock skapa problem för implementering och samarbete över sektorerna, bland annat genom genom dålig kommunikation mellan utredningsgrupper och den implementerande organisationen. Konservatism och maktkamp uttrycktes i form av en ovillighet från andra att samarbeta över sektorerna, att bryta det sektoriella tankesättet, och en vilja att värna om sin maktsfär.  Strukturella problem lyftes även fram som en av de bakomliggande anledninganar till att fiskeriernas negativa effekter inte fått mer fokus. Starkt kulturellt fäste, fokus på petroleumsverksamhet och dålig kunskapsförmedling var andra faktorer som togs upp. / Ecosystem based management is a management approach that seeks to integrate ecological, social and economic goals. The Norwegian management plan for the Barents Sea is one of the most advanced attempts to ecosystem based management. There is, however, still a long way to go to achieve the goals that have been set. This is especially true for the environmental objective of biodiversity. Even though fishing activity has been pointed out as one of the main reasons for biodiversity loss, little attention has been drawn to this fact. This paper therefore tries to give the answer to the questions of how people working within the management perceive the plan; the core values of it, its flaws, and why they beleave that the negative consequenses of fisheries have been out of focus.   The holistic viewpoint and the cooperation between the various sectors were the most emphazised values of the management plan. Organizational problems, conservatism, and power struggles were regarded as the main problems in trying to reach these goals. Lack of communication between  implementing bodies and investigating bodies was one example of this. Conservatism and power struggles were described as unwillingnes among individuals to adopt to the new intersectoral structures, and a wish to safeguard ones own power. The reason why the negative consequenses of fisheries have been out of focus, was also blamed on structural problems to a large extent. Other contributing factors were also the strong cultural role fisheries play in the norweigan society, the political focus on petroleum activity, and an insufficient spread of knowledge.

La mer de Barents possède un écosystème particulièrement riche. Elle est affectée par le changement climatique actuel, comme le reste de l'Arctique. L'effet le plus visible et le plus connu est la réduction spectaculaire de la banquise. On examine dans cette thèse les répercussions de ces changements sur l'hydrologie et le phytoplancton en mer de Barents. Pour cela, on s'appuie sur la création d'une base de données historiques comprenant les paramètres hydrologiques et bio-géochimiques. Un modèle 3D bio-géochimique spécifique à l'écosystème arctique est aussi utilisé quand les observations sont manquantes. Enfin, les données satellites fournissent des séries temporelles de concentration de glace, de Chlorophyle-a...La mer de Barents est caractérisée par un front polaire séparant les eaux atlantiques issues des mers Nordiques des eaux arctiques dont la position est connue à l'ouest de 35°E. Nous avons pu montrer que ce front se sépare en deux branches dans l'Est du bassin: le front du Nord et le front du Sud. Ces fronts enferment les eaux de la mer de Barents qui se forment en hiver. Un doublement du volume des eaux atlantiques (une " Atlantification " de la mer de Barents), a aussi été mise en évidence. Elle accompagne un déplacement des fronts Nord et Sud vers le Nord-est. Le volume des eaux de la mer de Barents reste inchangé.Ces changements, affectant l'hydrologie et la glace de Mer, ont un impact significatif sur le phytoplancton. Les deux efflorescences qui le caractérisent ont lieu plus au Nord et à l'Est. La biomasse totale annuelle a augmenté de 40% lors des deux dernières décennies. Ce travail montre que les conditions de glace de mer et la structure frontale sont les paramètres clefs dirigeant la variabilitéinter-annuelle du phytoplancton. / The Barents Sea has a particularly rich ecosystem. This is an Arctic region subject to intense climate changes. The drastic decrease in sea ice cover is the most visible effect. What are the impacts of these climatic changes on the hydrology and phytoplankton? In order to answer these questions, this thesis relies on the creation of an extensive historical database of physical and bio-geochemical parameters. A 3D bio-geochemical model with an Arctic specific ecosystem is used when observations are lacking. At least, remote sensing data provides valuable time series of Ice concentration, Chlorophyll-a... The Polar Front, separating the Atlantic Water coming from the Nordic Sea from the Arctic Water, is the principal feature of the Barents Sea region. Its position is known west of 35°E, but we showed that the polar front splits into two branches in the East part of the Barents Sea: the "Southern Front" and the "Northern Front". They enclose the winter locally formed Barents Sea Water. An “Atlantification”, illustrating a doubling of the Atlantic Water volume, has been evidenced and goes along with a North-eastward shift of the fronts. These hydrological and sea ice changes have a significant impact on the phytoplankton development. The two blooms of the Barents Sea occur further North and East with a 40% total anual biomass increase for the last two decades. This study suggests that the winter sea ice conditions and the frontal structure are the key mechanisms driving the inter-annual phytoplankton variability.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. Description based on print version record. Includes bibliographical references (leaves 127-133).