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	Provedor de dados 5 (8) 20 (5) Autor Bannerman, P. (1) Barbarin, Nicolas (1) Bauer, Robert (1) Beaufort, Luc (1) Cajas, J. (1) Carrillo, P. (1) Carton, Xavier (1) Castro, R. (1) Chavarría, J. (1) Cleroux, Caroline (1) Coello, D. (1) Cortijo, Elsa (1) Crucifix, Michel (1) Cuadra, T. de la (1) Daher, Abdourahman (1) De Garidel-thoron, Thibault (1) Droxler, Andre W. (1) Duplessy, Jean-claude (1) Duvielbourg, Eric (1) Elías, E. (1) Mais... Palavra-chave Thermocline (13) By catch (2) North Atlantic (2) Acoustic (1) Argo (1) Atlantic Ocean (1) Biogeochemical Structures (1) Biological sampling (1) Body length (1) Carbonate (1) Chaos (1) Classification North Atlantic (1) Climate change (1) Climatic changes (1) Climatic data (1) Cruise reports (1) Deep ocean ventilation rates (1) Deep-dwelling foraminifera (1) Deglacial (1) Depth habitat (1) Mais... Tipo do documento Text (8) Journal Contribution (5) Ano 2017 (2) 2016 (1) 2015 (3) 2013 (1) 2012 (1) 2010 (1) 2007 (1) 2005 (1) 2004 (1) 1996 (1) Mais... País France (8) Belgium (5) Idioma Inglês (9) Espanhol (4)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 13 Primeira ... 1 ... Última Atlantic Meridional Overturning Circulation during the Last Glacial and Deglacial: Inferences from the Atlantic Tropical Thermocline Temperature and Seawater Radiocarbon Activity 5 Huang, Enqing. This thesis aims to investigate variations of the last glacial and deglacial Atlantic Ocean circulation, with emphasize on the Atlantic deepwater ventilation rate during the Last Glacial Maximum (LGM). The highlights of the thesis are as the followings: (1) the modern frontal zone between the North Atlantic and the South Atlantic central waters off NW Africa shifted to the south during the last glacial and deglacial time periods. (2) The radiocarbon-based circulation age of the deep Atlantic (> 1500 m) was estimated to be less than 400 years during the LGM, which was equal to or less than its pre-bomb value. Therefore, the LGM deep Atlantic was inferred to be well ventilated. (3) The abyssal Atlantic (below 2500 m) prior to the LGM was more depleted in... Tipo: Text Palavras-chave: Climate change; Ocean circulation; Atlantic Ocean; Glacial; Deglacial; Thermocline; Radiocarbon; Global carbon cycle; Foraminifera; Carbonate; Trace elements; Deep ocean ventilation rates. Ano: 2013 URL: https://archimer.ifremer.fr/doc/00493/60446/63891.pdf Características oceanográficas frente a Ecuador durante noviembre de 1995 20 Cuadra, T. de la. In this work, the oceanographics and atmospheric index showed normals climatical conditions. The horizontal and vertical distributions obtained from 34 oceanographic stations, partitioned the area researched in two: The 1th area in association with weak upwelling in the south of Golfo de Guayaquil, and influenced probably the distributions and abundance of fishery resources. The 2th in the north of the point Sta Elena, in association with a strong thermocline. Tipo: Journal Contribution Palavras-chave: Oceanographic data; Climatic data; Thermocline; Climatic data; Http://aims.fao.org/aos/agrovoc/c_29553. Ano: 1996 URL: http://hdl.handle.net/1834/2967 Characterizing the chaotic nature of ocean ventilation 5 Macgilchrist, Graeme A.; Marshall, David P.; Johnson, Helen L.; Lique, Camille; Thomas, Matthew. Ventilation of the upper ocean plays an important role in climate variability on interannual to decadal timescales by influencing the exchange of heat and carbon dioxide between the atmosphere and ocean. The turbulent nature of ocean circulation, manifest in a vigorous mesoscale eddy field, means that pathways of ventilation, once thought to be quasi-laminar, are in fact highly chaotic. We characterize the chaotic nature of ventilation pathways according to a nondimensional filamentation number, which estimates the reduction in filament width of a ventilated fluid parcel due to mesoscale strain. In the subtropical North Atlantic of an eddy-permitting ocean model, the filamentation number is large everywhere across three upper ocean density... Tipo: Text Palavras-chave: Ventilation; North Atlantic; Thermocline; Chaos; Mesoscale eddies; Lagrangian trajectories. Ano: 2017 URL: https://archimer.ifremer.fr/doc/00410/52104/52807.pdf Coherent heat patterns revealed by unsupervised classification of Argo temperature profiles in the North Atlantic Ocean 5 Maze, Guillaume; Mercier, Herle; Fablet, Ronan; Tandeo, Pierre; Radcenco, Manuel Lopez; Lenca, Philippe; Feucher, Charlene; Le Goff, Clement. A quantitative understanding of the integrated ocean heat content depends on our ability to determine how heat is distributed in the ocean and what are the associated coherent patterns. This study demonstrates how this can be achieved using unsupervised classification of Argo temperature profiles. The classification method used is a Gaussian Mixture Model (GMM) that decomposes the Probability Density Function of a dataset into a weighted sum of Gaussian modes. It is determined that the North Atlantic Argo dataset of temperature profiles con- tains 8 groups of vertically coherent heat patterns, or classes. Each of the temperature profile classes reveals unique and physically coherent heat distributions along the vertical axis. A key result of this study is... Tipo: Text Palavras-chave: Heat content; Classification North Atlantic; Stratification; Water mass; Thermocline; Argo; Pattern. Ano: 2017 URL: http://archimer.ifremer.fr/doc/00363/47431/47456.pdf Deep-dwelling foraminifera as thermocline temperature recorders 5 Cleroux, Caroline; Cortijo, Elsa; Duplessy, Jean-claude; Zahn, Rainer. We measured the oxygen isotopic composition of the deep-dwelling foraminiferal species G. inflata, G. truncatulinoides dextral and sinistral, and P. obliquiloculata in 29 modern core tops raised from the North Atlantic Ocean. We compared calculated isotopic temperatures with atlas temperatures and defined ecological models for each species. G. inflata and G. truncatulinoides live preferentially at the base of the seasonal thermocline. Under temperature stress, i.e., when the base of the seasonal thermocline is warmer than 16 degrees C, G. inflata and G. truncatulinoides live deeper in the main thermocline. P. obliquiloculata inhabits the seasonal thermocline in warm regions. We tested our model using 10 cores along the Mauritanian upwelling and show that... Tipo: Text Palavras-chave: Deep-dwelling foraminifera; Depth habitat; Isotopic temperature; Thermocline; North Atlantic; Mauritanian upwelling; Ecological prediction; Stable isotopes; Micropaleontology. Ano: 2007 URL: https://archimer.ifremer.fr/doc/00236/34727/33178.pdf Effects of Monsoon Winds and Topographical Features on the Vertical Thermohaline and Biogeochemical Structure in the Gulf of Tadjourah (Djibouti) 5 Omar, Youssouf Moussa; Memery, Laurent; Carton, Xavier; Daher, Abdourahman; Duvielbourg, Eric. The vertical thermohaline and biogeochemical structures of the upper layer (0 - 200 m) were studied in the Gulf of Tadjourah using high-resolution hydrographic data collected in July-August 2013, September 2013 and February 2014. During summer, the superficial layer consisted of the mixed layer (ML) extending to a depth of about 20 - 30 m followed by the thermocline located between 30 and 50 m depth. The ML was thicker in the west and the southeast where the thermal gradient and chlorophyll a concentrations were particularly high. During September, this stratification persisted but the ML became warmer and saltier and the thermocline moved slightly deeper. In February, the ML extended to about 120 m, and the thermocline was less pronounced. A comparison of... Tipo: Text Palavras-chave: Thermohaline; Biogeochemical Structures; Mixed Layer Depth; Thermocline; Monsoon Wind; Topography. Ano: 2016 URL: https://archimer.ifremer.fr/doc/00601/71286/69693.pdf Las estaciones costeras y la vigilancia de "El Niño" en el Ecuador 20 Carrillo, P.; Zambrano Quiñonez, E.. Se revisa la estructura térmica de dos estaciones costeras del Ecuador ubicadas frente a los puertos de Salinas y Manta y se las compara con la boya oceánica de la NOAA, localizada en 0° y 140°W (Región Niño 3.4). Cada una de las tres estaciones tiene una isoterma característic que marca el inicio y fin de los eventos cálidos y fríos. Se advierte además que los eventos ENOS cuyo ONI es igual o superior que 1.8, considerados como fuertes o extraordinarios presentan una configuración termal muy similar en las tres estaciones aquí analizadas. Tipo: Journal Contribution Palavras-chave: Thermocline; El Nino phenomena; Thermal structure. Ano: 2012 URL: http://hdl.handle.net/1834/4718 Multiscale seismic reflectivity of shallow thermoclines 5 Ker, Stephan; Le Gonidec, Yves; Marie, Louis; Thomas, Yannick; Gibert, Dominique. Seismic Oceanography is coming of age as an established technique of observation of the thermohaline structure of the ocean. The present paper deals with the seismic reflectivity of the Armorican Shelf seasonal thermocline, west of France, based on two seismic experiments performed with a sparker source. The peak frequency was 500 Hz for the ASPEX experiment, where the thermocline was located at 27 m water depth, and reduced to 400 Hz associated to a higher source level for the IFOSISMO experiment, where the thermocline was 12 m deeper. Despite this settings, only the first experiment could clearly highlight the thermocline reflector, providing the first seismic observation of a shallow oceanic structure. To better understand the limitation of... Tipo: Text Palavras-chave: Thermocline; Seismic method; Wavelet analysis; Acoustic. Ano: 2015 URL: https://archimer.ifremer.fr/doc/00254/36535/35066.pdf Obervations on the commercial light fishing operation in Ghana 20 Quartey, R.; Bannerman, P.. Light fishing operations (LFO) in Ghana is concentrated in the three major coastal municipalities of Greater Accra (Tema), Central (Mumford & Elmina) and Western (Sekondi) Regions; these areas have the port facilities for landing of the catch by the larger inshore vessels that operate the purse seine fishery in Ghana and which predominantly operate the light attraction. Currently there are about 250 registered inshore vessels in the country whose sizes range between 39 – 60 feet , only a small fraction are actually working at the moment due to problems with spare parts and operations. Light attraction is the technique of aggregating fish by artificial light; and light fishing is the process of fishing the attracted fish by hooking, gill-netting or by... Tipo: Journal Contribution Palavras-chave: Lenght frequency; Body length; By catch; Fishery economics; Pelagic fisheries; Size composition; Thermocline; Pelagic fisheries; Http://aims.fao.org/aos/agrovoc/c_5659. Ano: 2005 URL: http://hdl.handle.net/1834/1267 Optimizing PAT data transmission: assessing the accuracy of temperature summary data to estimate environmental conditions 5 Bauer, Robert; Forget, Fabien; Fromentin, Jean-marc. Pop-up archival tags (PAT) provide summary and high-resolution time series data at predefined temporal intervals. The limited battery capabilities of PATs often restrict the transmission success and thus temporal coverage of both data products. While summary data are usually less affected by this problem, as a result of its lower size, it might be less informative. We here investigate the accuracy and feasibility of using temperature at depth summary data provided by PATs to describe encountered oceanographic conditions. Interpolated temperature at depth summary data was found to provide accurate estimates of three major thermal water column structure indicators: thermocline depth, stratification and ocean heat content. Such indicators are useful for the... Tipo: Text Palavras-chave: Mixed layer depth; Ocean heat content; Pop-up archival tags; PAT-style Depth-Temperature Profiles; Temperature at depth; Thermal stratification; Thermocline. Ano: 2015 URL: https://archimer.ifremer.fr/doc/00287/39800/45102.pdf Pesca exploratoria del recurso dorado (Coryphaena hippurus) frente a la costa ecuatoriana durante marzo de 2010 20 Herrera, M.; Coello, D.; Peralta, M.; Elías, E.; Cajas, J.; Castro, R.; Pesantes, F.; Chavarría, J.. Del 9 al 21 de marzo de 2010, se realizó el Crucero T10/03/01 durante el cual se efectuaron 10 lances de pesca entre 01º21.39' N-03º 02.55' S y entre las longitudes 080º 32.20' W-082º 57.08' W, empleando un palangre de superficie doradero. En los lances realizados frente a Esmeraldas y Manabí, se registraron las mayores capturas, con especímenes con mayor talla y peso promedio, con una temperatura superficial promedio de 27 ºC y termoclina ubicada entre los 10 y 50 m de profundidad con la isoterma de 20 ºC, próxima a la profundidad de cala de la línea de pesca. Hacia el sur (lances 7 al 10), ubicados frente al sur de Manabí, Península de Santa Elena y Golfo de Guayaquil. Las capturas estuvieron representadas por especímenes con talla y peso promedio... Tipo: Journal Contribution Palavras-chave: Exploratory fishing; Cruise reports; Biological sampling; Longlining; Thermocline; Feed composition; Stomach content; By catch. Ano: 2010 URL: http://hdl.handle.net/1834/4799 Progressive shoaling of the equatorial Pacific thermocline over the last eight glacial periods 5 Regoli, Fabienne; De Garidel-thoron, Thibault; Tachikawa, Kazuyo; Jian, Zhiming; Ye, Liming; Droxler, Andre W.; Lenoir, Guillaume; Crucifix, Michel; Barbarin, Nicolas; Beaufort, Luc. The depth of equatorial Pacific thermocline is diagnostic of the main modes of tropical climates. Past estimates of Pacific thermocline dynamics have been reconstructed either for the Last Glacial Maximum or on longer timescales at low resolution. Here we document a new high-resolution set of reconstructed past sea surface and subsurface waters temperatures from the southwestern subequatorial Pacific, core MD05-2930, in the Gulf of Papua, over the last 800 ka. We used two morphotypes of Globigerinoides ruber known to live at different water depths to reconstruct past stratification. We estimated calcification temperature of each morphotypes by Mg/Ca paleothermometry. Our subequatorial Pacific thermocline paleotemperature record indicates a response of the... Tipo: Text Palavras-chave: Equatorial Pacific; Thermocline; Pleistocene. Ano: 2015 URL: https://archimer.ifremer.fr/doc/00295/40572/39477.pdf Variaciones interanuales (1995-2000) de la temperatura y la salinidad registradas en los meses de enero en el golfo San Jorge y aguas adyacentes (43°S-47°S). 20 Louge, E.; Reta, R.; Santos, B.A.; Hernandez, D.R.. Temperature and salinity interannual variations are analyzed south ofthe hake (Merluccius hubbsi)spawning grounds area, in the San Jorge Gulf and adjacent waters Argentine Sea, SW Atlantic. The study period comprises the months of January 1995-2000. Results of cruises carried out on board of INIDEP research vessels to assess hake juveniles were studied. Statistically significant increase of temperature from 1997 was observed. Change trends over a period of 20 years at a global climate scale are discussed. Mean salinity did not show variations except for 2000 when it was slightly higher probably due to the scarce influence of the Patagonian Current in the area. Temperature and salinity fields showed a horizontal gradient south of the Gulf (thermohaline... Tipo: Journal Contribution Palavras-chave: Salinity; Temperature; Shelf fronts; Thermocline; Environmental factors; Nursery grounds; Climatic changes; Environmental factors; Salinity; Temperature; Nursery grounds; Http://aims.fao.org/aos/agrovoc/c_2594; Http://aims.fao.org/aos/agrovoc/c_6751; Http://aims.fao.org/aos/agrovoc/c_7657; Http://aims.fao.org/aos/agrovoc/c_25438. Ano: 2004 URL: http://hdl.handle.net/1834/1500 Registros recuperados: 13 Primeira ... 1 ... Última

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