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| Denis, Delphine; Crosta, Xavier; Schmidt, Sabine; Carson, Damien S.; Ganeshram, Raja S.; Renssen, Hans; Crespin, Julien; Ther, Olivier; Billy, Isabelle; Giraudeau, Jacques. |
| This study presents the first high-resolution multiproxy investigation of primary productivity ( PP) during the Holocene from the Antarctic continental margins. Micropaleontological and geochemical data from the sediment core MD03-2601, associated to sea ice model outputs, give unprecedented insights into the biological pump of the Antarctic coastal area off Adelie Land in response to climatic changes. Plurimillennial and millennial changes of PP are observed in the study area in response to changes in nutrient availability, stratification, and growing season duration, which are linked to sea ice, upwelling, wind, and glacier dynamics. The precessional cycle seems to be responsible in the PP long-term variations, while forcing factors involved at the... |
| Tipo: Text |
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| Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/00218/32930/31442.pdf |
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| Price, Andrea M.; Mertens, Kenneth; Pospelova, Vera; Pedersen, Thomas F.; Ganeshram, Raja S.. |
| A high-resolution record of organic-walled dinoflagellate cyst production in Guaymas Basin, Gulf of California (Mexico) reveals a complex paleoceanographic history over the last similar to 40 ka. Guaymas Basin is an excellent location to perform high resolution studies of changes in late Quaternary climate and paleo-productivity because it is characterized by high primary productivity, high sedimentation rates, and low oxygen bottom waters. These factors contribute to the deposition and preservation of laminated sediments throughout large portions of the core MD02-2515. In this study, we document dinoflagellate cyst production at a centennial to millennial scale throughout the late Quaternary. Based on the cyst assemblages, three dinoflagellate cyst zones... |
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| Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00262/37306/35718.pdf |
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| Ganeshram, Raja S.; Pedersen, Thomas F.; Calvert, Stephen E.; Mcneill, Gavin W.; Fontugne, Michel R.. |
| The late Quaternary history of water-column denitrification of the eastern Pacific margins and the Arabian Sea is reconstructed using sedimentary delta(15)N measurements. The delta(15)N values in six piston cores raised from these regions show remarkably similar cyclic variations, being heavy (9-10.5 parts per thousand) during the interglacials and 2-3 parts per thousand lighter during the glacials. This implies that denitrification in these regions decreased substantially during the glacial periods. The glacial decline in denitrification is attributed to reduced upwelling and flux of organic material through the oxygen minimum zone. Since water-column denitrification in these areas accounts for about half of the fixed-nitrogen loss in the modern ocean,... |
| Tipo: Text |
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| Ano: 2000 |
URL: https://archimer.ifremer.fr/doc/00220/33123/31655.pdf |
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| Schlitzer, Reiner; Anderson, Robert F.; Dodas, Elena Masferrer; Lohan, Maeve; Geibere, Walter; Tagliabue, Alessandro; Bowie, Andrew; Jeandel, Catherine; Maldonado, Maria T.; Landing, William M.; Cockwell, Donna; Abadie, Cyril; Abouchami, Wafa; Achterberg, Eric P.; Agather, Alison; Aguliar-islas, Ana; Van Aken, Hendrik M.; Andersen, Morten; Archer, Corey; Auro, Maureen; De Baar, Hein J.; Baars, Oliver; Baker, Alex R.; Bakker, Karel; Basak, Chandranath; Baskaran, Mark; Bates, Nicholas R.; Bauch, Dorothea; Van Beek, Pieter; Behrens, Melanie K.; Black, Erin; Bluhm, Katrin; Bopp, Laurent; Bouman, Heather; Bowman, Katlin; Bown, Johann; Boyd, Philip; Boye, Marie; Boyle, Edward A.; Branellec, Pierre; Bridgestock, Luke; Brissebrat, Guillaume; Browning, Thomas; Bruland, Kenneth W.; Brumsack, Hans-juergen; Brzezinski, Mark; Buck, Clifton S.; Buck, Kristen N.; Buesseler, Ken; Bull, Abby; Butler, Edward; Cai, Pinghe; Camara Mor, Patricia; Cardinal, Damien; Carlson, Craig; Carrasco, Gonzalo; Casacuberta, Nuria; Casciotti, Karen L.; Castrillejo, Maxi; Chamizo, Elena; Chance, Rosie; Charette, Matthew A.; Chaves, Joaquin E.; Cheng, Hai; Chever, Fanny; Christl, Marcus; Church, Thomas M.; Closset, Ivia; Colman, Albert; Conway, Tim M.; Cossa, Daniel; Croot, Peter; Cullen, Jay T.; Cutter, Gregory A.; Daniels, Chris; Dehairs, Frank; Deng, Feifei; Dieu, Huong Thi; Duggan, Brian; Dulaquais, Gabriel; Dumousseaud, Cynthia; Echegoyen-sanz, Yolanda; Edwards, R. Lawrence; Ellwood, Michael; Fahrbach, Eberhard; Fitzsimmons, Jessica N.; Flegal, A. Russell; Fleisher, Martin Q.; Van De Flierdt, Tina; Frank, Martin; Friedrich, Jana; Fripiat, Francois; Froellje, Henning; Galer, Stephen J. G.; Gamo, Toshitaka; Ganeshram, Raja S.; Garcia-orellana, Jordi; Garcia-solsona, Ester; Gault-ringold, Melanie; George, Ejin; Gerringa, Loes J. A.; Gilbert, Melissa; Godoy, Jose M.; Goldstein, Steven L.; Gonzalez, Santiago R.; Grissom, Karen; Hammerschmidt, Chad; Hartman, Alison; Hassler, Christel S.; Hathorne, Ed C.; Hatta, Mariko; Hawco, Nicholas; Hayes, Christopher T.; Heimburger, Lars-eric; Helgoe, Josh; Heller, Maija Iris; Henderson, Gideon M.; Henderson, Paul B.; Van Heuven, Steven; Ho, Peng; Horner, Tristan J.; Hsieh, Yu-te; Huang, Kuo-fang; Humphreys, Matthew P.; Isshiki, Kenji; Jacquot, Jeremy E.; Janssen, David J.; Jenkins, William J.; John, Seth; Jones, Elizabeth M.; Jones, Janice L.; Kadko, David C.; Kayser, Rick; Kenna, Timothy C.; Khondoker, Roulin; Kim, Taejin; Kipp, Lauren; Klar, Jessica K.; Klunder, Maarten; Kretschmer, Sven; Kumamoto, Yuichiro; Laan, Patrick; Labatut, Marie; Lacan, Francois; Lam, Phoebe J.; Lambelet, Myriam; Lamborg, Carl H.; Le Moigne, Frederic A. C.; Le Roy, Emilie; Lechtenfeld, Oliver J.; Lee, Jong-mi; Lherminier, Pascale; Little, Susan; Lopez-lora, Mercedes; Lu, Yanbin; Masque, Pere; Mawji, Edward; Mcclain, Charles R.; Measures, Christopher; Mehic, Sanjin; Barraqueta, Jan-lukas Menzel; Van Der Merwe, Pier; Middag, Rob; Mieruch, Sebastian; Milne, Angela; Minami, Tomoharu; Moffett, James W.; Moncoiffe, Gwenaelle; Moore, Willard S.; Morris, Paul J.; Morton, Peter L.; Nakaguchi, Yuzuru; Nakayama, Noriko; Niedermiller, John; Nishioka, Jun; Nishiuchi, Akira; Noble, Abigail; Obata, Hajime; Ober, Sven; Ohnemus, Daniel C.; Van Ooijen, Jan; O'Sullivan, Jeanette; Owens, Stephanie; Pahnke, Katharina; Paul, Maxence; Pavia, Frank; Pena, Leopoldo D.; Petersh, Brian; Planchon, Frederic; Planquette, Helene; Pradoux, Catherine; Puigcorbe, Viena; Quay, Paul; Queroue, Fabien; Radic, Amandine; Rauschenberg, S.; Rehkamper, Mark; Rember, Robert; Remenyi, Tomas; Resing, Joseph A.; Rickli, Joerg; Rigaud, Sylvain; Rijkenberg, Micha J. A.; Rintoul, Stephen; Robinson, Laura F.; Roca-marti, Montserrat; Rodellas, Valenti; Roeske, Tobias; Rolison, John M.; Rosenberg, Mark; Roshan, Saeed; Van Der Loaff, Michiel M. Rutgers; Ryabenko, Evgenia; Saito, Mak A.; Salt, Lesley A.; Sanial, Virginie; Sarthou, Geraldine; Schallenberg, Christina; Schauer, Ursula; Scher, Howie; Schlosser, Christian; Schnetger, Bernhard; Scott, Peter; Sedwick, Peter N.; Semiletov, Igor; Shelley, Rachel; Sherrell, Robert M.; Shiller, Alan M.; Sigman, Daniel M.; Singh, Sunil Kumar; Slagter, Hans A.; Slater, Emma; Smethie, William M.; Snaith, Helen; Sohrin, Yoshiki; Sohst, Bettina; Sonke, Jeroen E.; Speich, Sabrina; Steinfeldt, Reiner; Stewart, Gillian; Stichel, Torben; Stirling, Claudine H.; Stutsman, Johnny; Swarr, Gretchen J.; Swift, James H.; Thomas, Alexander; Thorne, Kay; Till, Claire P.; Till, Ralph; Townsend, Ashley T.; Townsend, Emily; Tuerena, Robyn; Twining, Benjamin S.; Vance, Derek; Velazquez, Sue; Venchiarutti, Celia; Villa-alfageme, Maria; Vivancos, Sebastian M.; Voelker, Antje H. L.; Wake, Bronwyn; Warner, Mark J.; Watson, Ros; Van Weerlee, Evaline; Weigand, M. Alexandra; Weinstein, Yishai; Weiss, Dominik; Wisotzki, Andreas; Woodward, E. Malcolm S.; Wu, Jingfeng; Wu, Yingzhe; Wuttig, Kathrin; Wyatt, Neil; Xiang, Yang; Xie, Ruifang C.; Xue, Zichen; Yoshikawa, Hisayuki; Zhang, Jing; Zhang, Pu; Zhao, Ye; Zheng, Linjie; Zheng, Xin-yuan; Zieringer, Moritz; Zimmer, Louise A.; Ziveri, Patrizia; Zunino, Patricia; Zurbrick, Cheryl. |
| The new IDP2017 is a significant improvement over the earlier IDP2014 and roughly doubles the number of included cruises, stations, samples and parameters. The IDP2017 is a truly international product containing data from 326 researchers from 25 countries. The IDP2017 provides data for the Pacific Ocean, and the Mediterranean and Black seas, in addition to Atlantic, Arctic and Indian Oceans that were already represented in the previous data product. For the first time, the IDP2017 contains significant amounts of biogeochemistry data as well as TEI data for aerosols and rain. As before, users can obtain complete IDP2017 data sets as bulk downloads. Alternatively, there is now a customisable online data extraction service that allows data selections by... |
| Tipo: Text |
Palavras-chave: GEOTRACES; Trace elements; Isotopes; Electronic atlas; IDP2017. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00442/55362/56877.pdf |
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| Pichevin, Laetitia; Ganeshram, Raja S.; Reynolds, Ben C.; Prahl, Fredrick; Pedersen, Thomas F.; Thunell, Robert; Mcclymont, Erin L.. |
| Iron is considered to play a large role in the cycling of Si in Fe-limited regions of the ocean, but little is known about its role in Si biogeochemistry outside these areas. Here, we present published sediment trap data, new nutrient profiles and high resolution sedimentary records (Si isotopes, Biogenic silica%, N% and C%) from the Gulf of California, a non-Fe-limited region, to investigate the history of Si cycling in this highly productive basin. Modern nutrient profiles show that silicic acid in subsurface waters is in excess relative to nitrate and is therefore incompletely utilized during moderate winter upwelling events. Modern data, however, suggest that during intense upwelling episodes, silicic acid is preferentially utilized relative to nitrate... |
| Tipo: Text |
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| Ano: 2012 |
URL: https://archimer.ifremer.fr/doc/00265/37665/36967.pdf |
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| Mcclymont, Erin L.; Ganeshram, Raja S.; Pichevin, Laetitia; Talbot, Helen M.; Van Dongen, Bart E.; Thunell, Robert C.; Haywood, Alan M.; Singarayer, Joy S.; Valdes, Paul J.. |
| Centennial-scale records of sea-surface temperature and opal composition spanning the Last Glacial Maximum and Termination 1 (circa 25-6 ka) are presented here from Guaymas Basin in the Gulf of California. Through the application of two organic geochemistry proxies, the U-37(K') index and the TEX86H index, we present evidence for rapid, stepped changes in temperatures during deglaciation. These occur in both temperature proxies at 13 ka (similar to 3 degrees C increase in 270 years), 10.0 ka (similar to 2 degrees C decrease over similar to 250 years) and at 8.2 ka (3 degrees C increase in <200 years). An additional rapid warming step is also observed in TEX86H at 11.5 ka. In comparing the two temperature proxies and opal content, we consider the... |
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| Ano: 2012 |
URL: https://archimer.ifremer.fr/doc/00265/37664/36972.pdf |
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| Pichevin, Laetitia; Ganeshram, Raja S.; Francavilla, Stephen; Arellano-torres, Elsa; Pedersen, Tom F.; Beaufort, Luc. |
| We present new high-resolution N isotope records from the Gulf of Tehuantepec and the Nicaragua Basin spanning the last 50-70 ka. The Tehuantepec site is situated within the core of the north subtropical denitrification zone while the Nicaragua site is at the southern boundary. The delta N-15 record from Nicaragua shows an "Antarctic" timing similar to denitrification changes observed off Peru-Chile but is radically different from the northern records. We attribute this to the leakage of isotopically heavy nitrate from the South Pacific oxygen minimum zone (OMZ) into the Nicaragua Basin. The Nicaragua record leads the other eastern tropical North Pacific (ETNP) records by about 1000 years because denitrification peaks in the eastern tropical South Pacific... |
| Tipo: Text |
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| Ano: 2010 |
URL: https://archimer.ifremer.fr/doc/00231/34244/32645.pdf |
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