Obata Hajime

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Obata
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Hajime
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  • Preprint
    The recent distribution of lead in the Indian Ocean reflects the impact of regional emissions
    ( 2014-09) Echegoyen, Yolanda ; Boyle, Edward A. ; Lee, Jong-Mi ; Gamo, Toshitaka ; Obata, Hajime ; Norisuye, Kazuhiro
    Humans have injected lead (Pb) massively into the earth surface environment in a temporally and spatially evolving pattern. A significant fraction is transported by the atmosphere into the surface ocean where we can observe its transport by ocean currents and sinking particles. This study of the Indian Ocean documents high Pb concentrations in the northern and tropical surface waters, and extremely low Pb levels in the deep water. North of 20°S, dissolved Pb concentrations decrease from 42-82 pmol/Kg in surface waters to 1.5-3.3 pmol/Kg in deep waters. South of 20°S, surface water Pb concentrations decrease from 21 pmol/Kg at 31°S to 7 pmol/Kg at 62°S. This surface Pb concentration gradient reflects a southward decrease in anthropogenic Pb emissions. The upper waters of the north and central Indian Ocean have high Pb concentrations resulting from recent regional rapid industrialization and a late phase-out of leaded gasoline, and these concentrations are now higher than currently seen in the central North Pacific and North Atlantic Oceans. The Antarctic sector of the Indian Ocean shows very low concentrations due to limited regional anthropogenic Pb emissions, high scavenging rates, and rapid vertical mixing, but Pb still occurs at higher levels than would have existed centuries ago. Penetration of Pb into the northern and central Indian Ocean thermocline waters is minimized by limited ventilation. Pb concentrations in the deep Indian Ocean are comparable to the other oceans at the same latitude, and deep waters of the central Indian Ocean match the lowest observed oceanic Pb concentrations.
  • Article
    The GEOTRACES Intermediate Data Product 2014
    (Elsevier, 2015-04-16) Mawji, Edward ; Schlitzer, Reiner ; Dodas, Elena Masferrer ; Abadie, Cyril ; Abouchami, Wafa ; Anderson, Robert F. ; Baars, Oliver ; Bakker, Karel ; Baskaran, Mark ; Bates, Nicholas R. ; Bluhm, Katrin ; Bowie, Andrew R. ; Bown, Johann ; Boye, Marie ; Marie, Edward A. ; Branellec, Pierre ; Bruland, Kenneth W. ; Brzezinski, Mark A. ; Bucciarelli, Eva ; Buesseler, Ken O. ; Butler, Edward ; Cai, Pinghe ; Cardinal, Damien ; Casciotti, Karen L. ; Chaves, Joaquin E. ; Cheng, Hai ; Chever, Fanny ; Church, Thomas M. ; Colman, Albert S. ; Conway, Tim M. ; Croot, Peter L. ; Cutter, Gregory A. ; Baar, Hein J. W. de ; de Souza, Gregory F. ; Dehairs, Frank ; Deng, Feifei ; Dieu, Huong Thi ; Dulaquais, Gabriel ; Echegoyen-Sanz, Yolanda ; Edwards, R. Lawrence ; Fahrbach, Eberhard ; Fitzsimmons, Jessica N. ; Fleisher, Martin Q. ; Frank, Martin ; Friedrich, Jana ; Fripiat, Francois ; Galer, Stephen J. G. ; Gamo, Toshitaka ; Garcia Solsona, Ester ; Gerringa, Loes J. A. ; Godoy, Jose Marcus ; Gonzalez, Santiago ; Grossteffan, Emilie ; Hatta, Mariko ; Hayes, Christopher T. ; Heller, Maija Iris ; Henderson, Gideon M. ; Huang, Kuo-Fang ; Jeandel, Catherine ; Jenkins, William J. ; John, Seth G. ; Kenna, Timothy C. ; Klunder, Maarten ; Kretschmer, Sven ; Kumamoto, Yuichiro ; Laan, Patrick ; Labatut, Marie ; Lacan, Francois ; Lam, Phoebe J. ; Lannuzel, Delphine ; le Moigne, Frederique ; Lechtenfeld, Oliver J. ; Lohan, Maeve C. ; Lu, Yanbin ; Masqué, Pere ; McClain, Charles R. ; Measures, Christopher I. ; Middag, Rob ; Moffett, James W. ; Navidad, Alicia ; Nishioka, Jun ; Noble, Abigail E. ; Obata, Hajime ; Ohnemus, Daniel C. ; Owens, Stephanie A. ; Planchon, Frederic ; Pradoux, Catherine ; Puigcorbe, Viena ; Quay, Paul D. ; Radic, Amandine ; Rehkamper, Mark ; Remenyi, Tomas A. ; Rijkenberg, Micha J. A. ; Rintoul, Stephen R. ; Robinson, Laura F. ; Roeske, Tobias ; Rosenberg, Mark ; Rutgers van der Loeff, Michiel M. ; Ryabenko, Evgenia ; Saito, Mak A. ; Roshan, Saeed ; Salt, Lesley ; Sarthou, Geraldine ; Schauer, Ursula ; Scott, Peter M. ; Sedwick, Peter N. ; Sha, Lijuan ; Shiller, Alan M. ; Sigman, Daniel M. ; Smethie, William M. ; Smith, Geoffrey J. ; Sohrin, Yoshiki ; Speich, Sabrina ; Stichel, Torben ; Stutsman, Johnny ; Swift, James H. ; Tagliabue, Alessandro ; Thomas, Alexander L. ; Tsunogai, Urumu ; Twining, Benjamin S. ; van Aken, Hendrik M. ; van Heuven, Steven ; van Ooijen, Jan ; van Weerlee, Evaline ; Venchiarutti, Celia ; Voelker, Antje H. L. ; Wake, Bronwyn ; Warner, Mark J. ; Woodward, E. Malcolm S. ; Wu, Jingfeng ; Wyatt, Neil ; Yoshikawa, Hisayuki ; Zheng, Xin-Yuan ; Xue, Zichen ; Zieringer, Moritz ; Zimmer, Louise A.
    The GEOTRACES Intermediate Data Product 2014 (IDP2014) is the first publicly available data product of the international GEOTRACES programme, and contains data measured and quality controlled before the end of 2013. It consists of two parts: (1) a compilation of digital data for more than 200 trace elements and isotopes (TEIs) as well as classical hydrographic parameters, and (2) the eGEOTRACES Electronic Atlas providing a strongly inter-linked on-line atlas including more than 300 section plots and 90 animated 3D scenes. The IDP2014 covers the Atlantic, Arctic, and Indian oceans, exhibiting highest data density in the Atlantic. The TEI data in the IDP2014 are quality controlled by careful assessment of intercalibration results and multi-laboratory data comparisons at cross-over stations. The digital data are provided in several formats, including ASCII spreadsheet, Excel spreadsheet, netCDF, and Ocean Data View collection. In addition to the actual data values the IDP2014 also contains data quality flags and 1-σ data error values where available. Quality flags and error values are useful for data filtering. Metadata about data originators, analytical methods and original publications related to the data are linked to the data in an easily accessible way. The eGEOTRACES Electronic Atlas is the visual representation of the IDP2014 data providing section plots and a new kind of animated 3D scenes. The basin-wide 3D scenes allow for viewing of data from many cruises at the same time, thereby providing quick overviews of large-scale tracer distributions. In addition, the 3D scenes provide geographical and bathymetric context that is crucial for the interpretation and assessment of observed tracer plumes, as well as for making inferences about controlling processes.
  • Article
    Hydrothermal impacts on trace element and isotope ocean biogeochemistry
    (The Royal Society, 2016-10-17) German, Christopher R. ; Casciotti, Karen L. ; Dutay, Jean-Claude ; Heimburger, Lars-Eric ; Jenkins, William J. ; Measures, Christopher I. ; Mills, Rachel A. ; Obata, Hajime ; Schlitzer, Reiner ; Tagliabue, Alessandro ; Turner, David R. ; Whitby, Hannah
    Hydrothermal activity occurs in all ocean basins, releasing high concentrations of key trace elements and isotopes (TEIs) into the oceans. Importantly, the calculated rate of entrainment of the entire ocean volume through turbulently mixing buoyant hydrothermal plumes is so vigorous as to be comparable to that of deep-ocean thermohaline circulation. Consequently, biogeochemical processes active within deep-ocean hydrothermal plumes have long been known to have the potential to impact global-scale biogeochemical cycles. More recently, new results from GEOTRACES have revealed that plumes rich in dissolved Fe, an important micronutrient that is limiting to productivity in some areas, are widespread above mid-ocean ridges and extend out into the deep-ocean interior. While Fe is only one element among the full suite of TEIs of interest to GEOTRACES, these preliminary results are important because they illustrate how inputs from seafloor venting might impact the global biogeochemical budgets of many other TEIs. To determine the global impact of seafloor venting, however, requires two key questions to be addressed: (i) What processes are active close to vent sites that regulate the initial high-temperature hydrothermal fluxes for the full suite of TEIs that are dispersed through non-buoyant hydrothermal plumes? (ii) How do those processes vary, globally, in response to changing geologic settings at the seafloor and/or the geochemistry of the overlying ocean water? In this paper, we review key findings from recent work in this realm, highlight a series of key hypotheses arising from that research and propose a series of new GEOTRACES modelling, section and process studies that could be implemented, nationally and internationally, to address these issues.
  • Article
    The GEOTRACES Intermediate Data Product 2017
    (Elsevier, 2018-06-01) Schlitzer, Reiner ; Anderson, Robert F. ; Dodas, Elena Masferrer ; Lohan, Maeve C. ; Geibert, Walter ; Tagliabue, Alessandro ; Bowie, Andrew R. ; 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 E. ; Baar, Hein J. W. de ; Baars, Oliver ; Baker, Alex R. ; Bakker, Karel ; Basak, Chandranath ; Baskaran, Mark ; Bates, Nicholas R. ; Bauch, Dorothea ; van Beek, Pieter ; Behrens, Melanie K. ; Black, Erin E. ; 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 A. ; Bruland, Kenneth W. ; Brumsack, Hans-Jürgen ; Brzezinski, Mark A. ; Buck, Clifton S. ; Buck, Kristen N. ; Buesseler, Ken O. ; Bull, Abby ; Butler, Edward ; Cai, Pinghe ; Cámara 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 S. ; Conway, Tim M. ; Cossa, Daniel ; Croot, Peter L. ; 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 J. ; Fahrbach, Eberhard ; Fitzsimmons, Jessica N. ; Flegal, A. Russell ; Fleisher, Martin Q. ; van de Flierdt, Tina ; Frank, Martin ; Friedrich, Jana ; Fripiat, Francois ; Fröllje, 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 Marcus ; Goldstein, Steven L. ; Gonzalez, Santiago ; Grissom, Karen ; Hammerschmidt, Chad R. ; Hartman, Alison ; Hassler, Christel ; Hathorne, Ed C. ; Hatta, Mariko ; Hawco, Nicholas J. ; Hayes, Christopher T. ; Heimbürger, 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 ; 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, Frederique ; Le Roy, Emilie ; Lechtenfeld, Oliver J. ; Lee, Jong-Mi ; Lherminier, Pascale ; Little, Susan ; López-Lora, Mercedes ; Lu, Yanbin ; Masque, Pere ; Mawji, Edward ; McClain, Charles R. ; Measures, Christopher I. ; Mehic, Sanjin ; Menzel Barraqueta, Jan-Lukas ; Merwe, Pier van der ; 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 E. ; Obata, Hajime ; Ober, Sven ; Ohnemus, Daniel C. ; van Ooijen, Jan ; O'Sullivan, Jeanette ; Owens, Stephanie A. ; Pahnke, Katharina ; Paul, Maxence ; Pavia, Frank ; Pena, Leopoldo D. ; Peters, Brian ; Planchon, Frederic ; Planquette, Helene ; Pradoux, Catherine ; Puigcorbé, Viena ; Quay, Paul D. ; Queroue, Fabien ; Radic, Amandine ; Rauschenberg, Sara ; Rehkämper, Mark ; Rember, Robert ; Remenyi, Tomas A. ; Resing, Joseph A. ; Rickli, Joerg ; Rigaud, Sylvain ; Rijkenberg, Micha J. A. ; Rintoul, Stephen R. ; Robinson, Laura F. ; Roca-Martí, Montserrat ; Rodellas, Valenti ; Roeske, Tobias ; Rolison, John M. ; Rosenberg, Mark ; Roshan, Saeed ; Rutgers van der Loeff, Michiel M. ; Ryabenko, Evgenia ; Saito, Mak A. ; Salt, Lesley ; Sanial, Virginie ; Sarthou, Geraldine ; Schallenberg, Christina ; Schauer, Ursula ; Scher, Howie ; Schlosser, Christian ; Schnetger, Bernhard ; Scott, Peter M. ; Sedwick, Peter N. ; Semiletov, Igor P. ; Shelley, Rachel U. ; Sherrell, Robert M. ; Shiller, Alan M. ; Sigman, Daniel M. ; Singh, Sunil Kumar ; Slagter, Hans ; Slater, Emma ; Smethie, William M. ; Snaith, Helen ; Sohrin, Yoshiki ; Sohst, Bettina M. ; 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 GEOTRACES Intermediate Data Product 2017 (IDP2017) is the second publicly available data product of the international GEOTRACES programme, and contains data measured and quality controlled before the end of 2016. The IDP2017 includes data from the Atlantic, Pacific, Arctic, Southern and Indian oceans, with about twice the data volume of the previous IDP2014. For the first time, the IDP2017 contains data for a large suite of biogeochemical parameters as well as aerosol and rain data characterising atmospheric trace element and isotope (TEI) sources. The TEI data in the IDP2017 are quality controlled by careful assessment of intercalibration results and multi-laboratory data comparisons at crossover stations. The IDP2017 consists of two parts: (1) a compilation of digital data for more than 450 TEIs as well as standard hydrographic parameters, and (2) the eGEOTRACES Electronic Atlas providing an on-line atlas that includes more than 590 section plots and 130 animated 3D scenes. The digital data are provided in several formats, including ASCII, Excel spreadsheet, netCDF, and Ocean Data View collection. Users can download the full data packages or make their own custom selections with a new on-line data extraction service. In addition to the actual data values, the IDP2017 also contains data quality flags and 1-σ data error values where available. Quality flags and error values are useful for data filtering and for statistical analysis. Metadata about data originators, analytical methods and original publications related to the data are linked in an easily accessible way. The eGEOTRACES Electronic Atlas is the visual representation of the IDP2017 as section plots and rotating 3D scenes. The basin-wide 3D scenes combine data from many cruises and provide quick overviews of large-scale tracer distributions. These 3D scenes provide geographical and bathymetric context that is crucial for the interpretation and assessment of tracer plumes near ocean margins or along ridges. The IDP2017 is the result of a truly international effort involving 326 researchers from 25 countries. This publication provides the critical reference for unpublished data, as well as for studies that make use of a large cross-section of data from the IDP2017. This article is part of a special issue entitled: Conway GEOTRACES - edited by Tim M. Conway, Tristan Horner, Yves Plancherel, and Aridane G. González.