Consulta: creatorFacets:"Trull, Thomas W."
Registros recuperados: 6
Data/hora: 03/06/2024 05:19:24

Differentiating Lithogenic Supplies, Water Mass Transport, and Biological Processes On and Off the Kerguelen Plateau Using Rare Earth Element Concentrations and Neodymium Isotopic Compositions
Provedor de dados: 5
Autores: Grenier, Melanie; Garcia-solsona, Ester; Lemaitre, Nolwenn; Trull, Thomas W.; Bouvier, Vincent; Nonnotte, Philippe; Van Beek, Pieter; Souhaut, Marc; Lacan, Francois; Jeandel, Catherine.
Distributions of dissolved rare earth element (REE) concentrations and neodymium isotopic compositions (expressed as epsilon(Nd)) of seawater over and off the Kerguelen Plateau in the Southern Ocean are presented. The sampling took place during the austral spring bloom in October-November 2011 (KEOPS2 project, GEOTRACES process study) and aimed to further the investigations of the KEOPS1 austral summer study in terms of sources and transport of lithogenic material, and to investigate the impact of local biogeochemical cycles on the REE distributions. The REE signature of the coastal eastern Kerguelen Islands waters was characterized by negative europium anomalies (Eu/Eu*) and negative epsilon(Nd) in filtered samples. By contrast, the unfiltered sample...
Tipo: Text
Palavras-chave: Southern Ocean; Kerguelen Islands; Rare earth elements; Fractionation; Anomalies; Lithogenic; Biologic; GEOTRACES.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00616/72764/72274.pdf

The fate of diatom valves in the Subantarctic and Polar Frontal Zones of the Southern Ocean: Sediment trap versus surface sediment assemblages
Provedor de dados: 5
Autores: Rigual-hernandez, Andres S.; Trull, Thomas W.; Bray, Stephen G.; Armand, Leanne K.
An array of deep ocean sediment traps was initiated in 1997 within the Australian sector of the Southern Ocean, and serviced annually for over a decade (the Subantarctic site is ongoing as part of the Southern Ocean Time Series). Here, we expand on previous findings obtained from the shallow traps (~ 1000 m depth) in the Polar Frontal Zone (PFZ) and Subantarctic Zone (SAZ) by examining the chemical composition and diatom assemblages collected by sediment traps deployed at bathypelagic depths in the PFZ (1500 m depth; years 1997–1998, 1999–2000 and 2003–2004) and SAZ (2000 and 3800 m; year 1999–2000). Additionally, the diatom assemblages of the surface sediments below the traps were analyzed to document how the seasonal signal is recorded in the sedimentary...
Tipo: Text
Palavras-chave: Diatoms; POC; Sediment traps; Surface sediments; Subantarctic Zone; Polar Frontal Zone.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00341/45215/44642.pdf

Phytoplankton morphology controls on marine snow sinking velocity
Provedor de dados: 5
Autores: Laurenceau-cornec, Emmanuel C.; Trull, Thomas W.; Davies, Diana M.; De La Rocha, Christina L.; Blain, Stephane.
During the second KErguelen Ocean and Plateau compared Study (KEOPS2) in October-November 2011, marine snow was formed in roller tanks by physical aggregation of phytoplankton assemblages sampled at 6 stations over and downstream of the Kerguelen Plateau. Sinking velocities, morphology, bulk composition (transparent exopolymer particles, biogenic silica, particulate organic carbon), and phytoplankton contents were measured individually on 66 aggregates to identify controls on sinking velocities. Equivalent spherical diameters (ESD) ranged from 1 to 12 mm, and the particle aspect ratios, Corey shape factors, and fractal dimensions (D-F1 = 1.5, D-F2 = 1.8) were close to those of smaller natural aggregates (0.2 to 1.5 mm) collected in polyacrylamide...
Tipo: Text
Palavras-chave: Sinking velocity Marine snow; Aggregation; Phytoplankton; Porosity.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00352/46275/46044.pdf

Optical imaging of mesopelagic particles indicates deep carbon flux beneath a natural iron-fertilized bloom in the Southern Ocean
Provedor de dados: 5
Autores: Jouandet, Marie-paule; Trull, Thomas W.; Guidi, Lionel; Picheral, Marc; Ebersbach, Friederike; Stemmann, Lars; Blain, Stephane.
We recorded vertical profiles of size distributions of particles (ranging from 0.052 to several mm in equivalent spherical diameter) in the natural iron-fertilized bloom southeast of Kerguelen Island (Southern Ocean) and in surrounding high-nutrient, low-chlorophyll (HNLC) waters with an Under Water Video Profiler during the Kerguelen Ocean and Plateau Compared Study cruise (Jan-Feb 2005). Total particle numerical abundance and total particle volume (TPV) in the 0-200-m layer were respectively 3-fold and 20-fold higher in the bloom, and integrated TPV was correlated to integrated chlorophyll concentration. The difference persisted well into the ocean interior with a 10-fold higher TPV at 400-m depth beneath the natural iron-fertilized bloom. Below 400 m,...
Tipo: Text
Ano: 2011
URL: https://archimer.ifremer.fr/doc/00214/32507/30994.pdf

On the Future of Argo: A Global, Full-Depth, Multi-Disciplinary Array
Provedor de dados: 5
Autores: Roemmich, Dean; Alford, Matthew H.; Claustre, Hervé; Johnson, Kenneth; King, Brian; Moum, James; Oke, Peter; Owens, W. Brechner; Pouliquen, Sylvie; Purkey, Sarah; Scanderbeg, Megan; Suga, Toshio; Wijffels, Susan; Zilberman, Nathalie; Bakker, Dorothee; Baringer, Molly; Belbeoch, Mathieu; Bittig, Henry C.; Boss, Emmanuel; Calil, Paulo; Carse, Fiona; Carval, Thierry; Chai, Fei; Conchubhair, Diarmuid Ó.; D’ortenzio, Fabrizio; Dall’olmo, Giorgio; Desbruyeres, Damien; Fennel, Katja; Fer, Ilker; Ferrari, Raffaele; Forget, Gael; Freeland, Howard; Fujiki, Tetsuichi; Gehlen, Marion; Greenan, Blair; Hallberg, Robert; Hibiya, Toshiyuki; Hosoda, Shigeki; Jayne, Steven; Jochum, Markus; Johnson, Gregory C.; Kang, Kiryong; Kolodziejczyk, Nicolas; Körtzinger, Arne; Traon, Pierre-yves Le; Lenn, Yueng-djern; Maze, Guillaume; Mork, Kjell Arne; Morris, Tamaryn; Nagai, Takeyoshi; Nash, Jonathan; Garabato, Alberto Naveira; Olsen, Are; Pattabhi, Rama Rao; Prakash, Satya; Riser, Stephen; Schmechtig, Catherine; Schmid, Claudia; Shroyer, Emily; Sterl, Andreas; Sutton, Philip; Talley, Lynne; Tanhua, Toste; Thierry, Virginie; Thomalla, Sandy; Toole, John; Troisi, Ariel; Trull, Thomas W.; Turton, Jon; Velez-belchi, Pedro Joaquin; Walczowski, Waldemar; Wang, Haili; Wanninkhof, Rik; Waterhouse, Amy F.; Waterman, Stephanie; Watson, Andrew; Wilson, Cara; Wong, Annie P. S.; Xu, Jianping; Yasuda, Ichiro.
The Argo Program has been implemented and sustained for almost two decades, as a global array of about 4000 profiling floats. Argo provides continuous observations of ocean temperature and salinity versus pressure, from the sea surface to 2000 dbar. The successful installation of the Argo array and its innovative data management system arose opportunistically from the combination of great scientific need and technological innovation. Through the data system, Argo provides fundamental physical observations with broad societally-valuable applications, built on the cost-efficient and robust technologies of autonomous profiling floats. Following recent advances in platform and sensor technologies, even greater opportunity exists now than 20 years ago to (i)...
Tipo: Text
Palavras-chave: Argo; Floats; Global; Ocean; Warming; Circulation; Temperature; Salinity.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00509/62043/66192.pdf

A BGC-Argo Guide: Planning, Deployment, Data Handling and Usage
Provedor de dados: 5
Autores: Bittig, Henry C.; Maurer, Tanya L.; Plant, Joshua N.; Schmechtig, Catherine; Wong, Annie P. S.; Claustre, Hervé; Trull, Thomas W.; Udaya Bhaskar, T. V. S.; Boss, Emmanuel; Dall’olmo, Giorgio; Organelli, Emanuele; Poteau, Antoine; Johnson, Kenneth S.; Hanstein, Craig; Leymarie, Edouard; Le Reste, Serge; Riser, Stephen C.; Rupan, A. Rick; Taillandier, Vincent; Thierry, Virginie; Xing, Xiaogang.
The Biogeochemical-Argo program (BGC-Argo) is a new profiling-float-based, ocean wide, and distributed ocean monitoring program which is tightly linked to, and has benefited significantly from, the Argo program. The community has recommended for BGC-Argo to measure six additional properties in addition to pressure, temperature and salinity measured by Argo, to include oxygen, pH, nitrate, downwelling light, chlorophyll fluorescence and the optical backscattering coefficient. The purpose of this addition is to enable the monitoring of ocean biogeochemistry and health, and in particular, monitor major processes such as ocean deoxygenation, acidification and warming and their effect on phytoplankton, the main source of energy of marine ecosystems. Here we...
Tipo: Text
Palavras-chave: Ocean observation; Ocean biogeochemical cycles; Sensors; Carbon cycle; Ocean optics; Best practices; Argo.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00512/62344/66607.pdf