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2. Groundwater discharge impacts marine isotope budgets of Li, Mg, Ca, Sr, and Ba

Author

Mayfield, Kimberley K, Eisenhauer, Anton, Santiago Ramos, Danielle P, Higgins, John A, Horner, Tristan J, Auro, Maureen, Magna, Tomas, Moosdorf, Nils, Charette, Matthew A, Gonneea, Meagan Eagle, Brady, Carolyn E, Komar, Nemanja, Peucker-Ehrenbrink, Bernhard, and Paytan, Adina

Subjects
Climate Change Impacts and Adaptation, Earth Sciences, Environmental Sciences, Geochemistry, Geology, Life Below Water
Abstract

Groundwater-derived solute fluxes to the ocean have long been assumed static and subordinate to riverine fluxes, if not neglected entirely, in marine isotope budgets. Here we present concentration and isotope data for Li, Mg, Ca, Sr, and Ba in coastal groundwaters to constrain the importance of groundwater discharge in mediating the magnitude and isotopic composition of terrestrially derived solute fluxes to the ocean. Data were extrapolated globally using three independent volumetric estimates of groundwater discharge to coastal waters, from which we estimate that groundwater-derived solute fluxes represent, at a minimum, 5% of riverine fluxes for Li, Mg, Ca, Sr, and Ba. The isotopic compositions of the groundwater-derived Mg, Ca, and Sr fluxes are distinct from global riverine averages, while Li and Ba fluxes are isotopically indistinguishable from rivers. These differences reflect a strong dependence on coastal lithology that should be considered a priority for parameterization in Earth-system models.

Published
2021

12. Zinc stimulation of coastal productivity in low carbon dioxide environments

Author

Kell, Riss M., primary, Subhas, Adam V., additional, Schanke, Nicole L., additional, Lees, Lauren E., additional, Chmiel, Rebecca J., additional, Rao, Deepa, additional, Brisbin, Margaret M., additional, Moran, Dawn M., additional, McIlvin, Matthew R., additional, Bolinesi, Francesco, additional, Mangoni, Olga, additional, Casotti, Raffaella, additional, Balestra, Cecilia, additional, Horner, Tristan J., additional, Dunbar, Robert B., additional, Allen, Andrew E., additional, DiTullio, Giacomo R., additional, and Saito, Mak A., additional

Published
2023
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15. Cadmium isotope fractionation in seawater : driving mechanisms and palaeoceanographic applications

Author

Horner, Tristan J., Henderson, Gideon M., and Rickaby, Rosalind E. M.

Subjects
551.9, Earth sciences, Geochemistry, Geobiology, Cadmium, Cadmium Isotope, Isotope Fractionation, Seawater, Trace Metal
Abstract

The global marine distributions of Cd and phosphate are closely correlated, which has led to Cd being considered as a marine micronutrient. Recent developments in Cd stable isotope mass spectrometry have revealed that Cd uptake by phytoplankton causes isotopic fractionation in the open ocean and in culture. The explanation for this nutrient-like behaviour is unknown as there is only one identified biochemical function for Cd, an unusual Cd/Zn carbonic anhydrase (CdCA1). This thesis investigates why Cd appears to act as an algal nutrient by performing subcellular analyses of microorganisms genetically-modified to express the CdCA1 gene. It was found that CdCA1 was not a significant contributor to whole-cell Cd isotope compositions. Instead, a large proportion of the internalized Cd is sequestered into cell membranes with a similar direction and magnitude of Cd isotopic fractionation as seen in surface seawater. This observation is explained if Cd is mistakenly imported with other divalent metals and subsequently managed by binding within the cell to avoid toxicity. This result implies that surface seawater Cd isotope compositions, if captured by an appropriate archive, may be invaluable for reconstructions of past marine productivity. The role of environmental factors in modulating the inorganic partitioning of Cd isotopes into calcite was investigated through a series of laboratory analogue experiments. In seawater, the light isotopes of Cd are always preferred in calcite. The magnitude of fractionation showed no response to temperature, ambient [Mg], or precipitation rate. To further identify suitable palaeaoceanographic archives, the Cd isotopic composition of a suite of modern deep-sea corals were investigated. It was found that the Cd/Ca and Cd isotope composition of coralline calcium carbonate followed the predicted trend for closed-system Rayleigh fractionation in the calcifying space. The lack of isotopic offsets between some corals and seawater will simplify the application of Cd isotopes in deep-sea corals -- and potentially other marine calcifying organisms that vacuolize seawater prior to calcium carbonate precipitation -- to palaeoceanography.

Published
2012

16. The GEOTRACES Intermediate Data Product 2017

Author

Schlitzer, Reiner, Anderson, Robert F., Dodas, Elena Masferrer, Lohan, Maeve, Geibert, 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-Jürgen, Brzezinski, Mark, Buck, Clifton S., Buck, Kristen N., Buesseler, Ken, Bull, Abby, Butler, Edward, Cai, Pinghe, Mor, Patricia Cámara, Cardinal, Damien, Carlson, Craig, Carrasco, Gonzalo, Casacuberta, Núria, 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., Russell Flegal, A., 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 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., Heimbürger, Lars-Eric, Helgoe, Josh, Heller, Maija, 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, Frédéric A.C., 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, 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., Peters, Brian, Planchon, Frederic, Planquette, Helene, Pradoux, Catherine, Puigcorbé, Viena, Quay, Paul, Queroue, Fabien, Radic, Amandine, Rauschenberg, S., Rehkämper, Mark, Rember, Robert, Remenyi, Tomas, Resing, Joseph A., Rickli, Joerg, Rigaud, Sylvain, Rijkenberg, Micha J.A., Rintoul, Stephen, 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 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, Alexandra Weigand, M., 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, and Zurbrick, Cheryl

Published
2018
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17. Barium in seawater: dissolved distribution, relationship to silicon, and barite saturation state determined using machine learning.

Author

Mete, Öykü Z., Subhas, Adam V., Kim, Heather H., Dunlea, Ann G., Whitmore, Laura M., Shiller, Alan M., Gilbert, Melissa, Leavitt, William D., and Horner, Tristan J.

Subjects
MACHINE learning, BARITE, OCEANOGRAPHIC observations, KRIGING, SEAWATER, SEAWATER salinity
Abstract

Barium is widely used as a proxy for dissolved silicon and particulate organic carbon fluxes in seawater. However, these proxy applications are limited by insufficient knowledge of the dissolved distribution of Ba ([Ba]). For example, there is significant spatial variability in the barium–silicon relationship, and ocean chemistry may influence sedimentary Ba preservation. To help address these issues, we developed 4095 models for predicting [Ba] using Gaussian process regression machine learning. These models were trained to predict [Ba] from standard oceanographic observations using GEOTRACES data from the Arctic, Atlantic, Pacific, and Southern oceans. Trained models were then validated by comparing predictions against withheld [Ba] data from the Indian Ocean. We find that a model trained using depth, temperature, and salinity, as well as dissolved dioxygen, phosphate, nitrate, and silicate, can accurately predict [Ba] in the Indian Ocean with a mean absolute percentage deviation of 6.0 %. We use this model to simulate [Ba] on a global basis using these same seven predictors in the World Ocean Atlas. The resulting [Ba] distribution constrains the Ba budget of the ocean to 122(± 7) × 10 12 mol and reveals oceanographically consistent variability in the barium–silicon relationship. We then calculate the saturation state of seawater with respect to barite. This calculation reveals systematic spatial and vertical variations in marine barite saturation and shows that the ocean below 1000 m is at equilibrium with respect to barite. We describe a number of possible applications for our model outputs, ranging from use in mechanistic biogeochemical models to paleoproxy calibration. Our approach demonstrates the utility of machine learning in accurately simulating the distributions of tracers in the sea and provides a framework that could be extended to other trace elements. Our model, the data used in training and validation, and global outputs are available in Horner and Mete (2023, 10.26008/1912/bco-dmo.885506.2). [ABSTRACT FROM AUTHOR]

Published
2023
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20. Strong Margin Influence on the Arctic Ocean Barium Cycle Revealed by Pan‐Arctic Synthesis

Author

Whitmore, Laura M., primary, Shiller, Alan M., additional, Horner, Tristan J., additional, Xiang, Yang, additional, Auro, Maureen E., additional, Bauch, Dorothea, additional, Dehairs, Frank, additional, Lam, Phoebe J., additional, Li, Jingxuan, additional, Maldonado, Maria T., additional, Mears, Chantal, additional, Newton, Robert, additional, Pasqualini, Angelica, additional, Planquette, Hélène, additional, Rember, Robert, additional, and Thomas, Helmuth, additional

Published
2022
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22. Hydrothermal trace metal release and microbial metabolism in the northeastern Lau Basin of the South Pacific Ocean

Author

Cohen, Natalie R., primary, Noble, Abigail E., additional, Moran, Dawn M., additional, McIlvin, Matthew R., additional, Goepfert, Tyler J., additional, Hawco, Nicholas J., additional, German, Christopher R., additional, Horner, Tristan J., additional, Lamborg, Carl H., additional, McCrow, John P., additional, Allen, Andrew E., additional, and Saito, Mak A., additional

Published
2021
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23. The Sedimentary Geochemistry and Paleoenvironments Project

Author

Farrell, Úna C., primary, Samawi, Rifaat, additional, Anjanappa, Savitha, additional, Klykov, Roman, additional, Adeboye, Oyeleye O., additional, Agic, Heda, additional, Ahm, Anne‐Sofie C., additional, Boag, Thomas H., additional, Bowyer, Fred, additional, Brocks, Jochen J., additional, Brunoir, Tessa N., additional, Canfield, Donald E., additional, Chen, Xiaoyan, additional, Cheng, Meng, additional, Clarkson, Matthew O., additional, Cole, Devon B., additional, Cordie, David R., additional, Crockford, Peter W., additional, Cui, Huan, additional, Dahl, Tais W., additional, Mouro, Lucas D., additional, Dewing, Keith, additional, Dornbos, Stephen Q., additional, Drabon, Nadja, additional, Dumoulin, Julie A., additional, Emmings, Joseph F., additional, Endriga, Cecilia R., additional, Fraser, Tiffani A., additional, Gaines, Robert R., additional, Gaschnig, Richard M., additional, Gibson, Timothy M., additional, Gilleaudeau, Geoffrey J., additional, Gill, Benjamin C., additional, Goldberg, Karin, additional, Guilbaud, Romain, additional, Halverson, Galen P., additional, Hammarlund, Emma U., additional, Hantsoo, Kalev G., additional, Henderson, Miles A., additional, Hodgskiss, Malcolm S.W., additional, Horner, Tristan J., additional, Husson, Jon M., additional, Johnson, Benjamin, additional, Kabanov, Pavel, additional, Brenhin Keller, C., additional, Kimmig, Julien, additional, Kipp, Michael A., additional, Knoll, Andrew H., additional, Kreitsmann, Timmu, additional, Kunzmann, Marcus, additional, Kurzweil, Florian, additional, LeRoy, Matthew A., additional, Li, Chao, additional, Lipp, Alex G., additional, Loydell, David K., additional, Lu, Xinze, additional, Macdonald, Francis A., additional, Magnall, Joseph M., additional, Mänd, Kaarel, additional, Mehra, Akshay, additional, Melchin, Michael J., additional, Miller, Austin J., additional, Mills, N. Tanner, additional, Mwinde, Chiza N., additional, O'Connell, Brennan, additional, Och, Lawrence M., additional, Ossa Ossa, Frantz, additional, Pagès, Anais, additional, Paiste, Kärt, additional, Partin, Camille A., additional, Peters, Shanan E., additional, Petrov, Peter, additional, Playter, Tiffany L., additional, Plaza‐Torres, Stephanie, additional, Porter, Susannah M., additional, Poulton, Simon W., additional, Pruss, Sara B., additional, Richoz, Sylvain, additional, Ritzer, Samantha R., additional, Rooney, Alan D., additional, Sahoo, Swapan K., additional, Schoepfer, Shane D., additional, Sclafani, Judith A., additional, Shen, Yanan, additional, Shorttle, Oliver, additional, Slotznick, Sarah P., additional, Smith, Emily F., additional, Spinks, Sam, additional, Stockey, Richard G., additional, Strauss, Justin V., additional, Stüeken, Eva E., additional, Tecklenburg, Sabrina, additional, Thomson, Danielle, additional, Tosca, Nicholas J., additional, Uhlein, Gabriel J., additional, Vizcaíno, Maoli N., additional, Wang, Huajian, additional, White, Tristan, additional, Wilby, Philip R., additional, Woltz, Christina R., additional, Wood, Rachel A., additional, Xiang, Lei, additional, Yurchenko, Inessa A., additional, Zhang, Tianran, additional, Planavsky, Noah J., additional, Lau, Kimberly V., additional, Johnston, David T., additional, and Sperling, Erik A., additional

Published
2021
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24. Supplementary material to "Hydrothermal trace metal release and microbial metabolism in the Northeast Lau Basin of the south Pacific Ocean"

Author

Cohen, Natalie R., primary, Noble, Abigail E., additional, Moran, Dawn M., additional, McIlvin, Matthew R., additional, Goepfert, Tyler J., additional, Hawco, Nicholas J., additional, German, Christopher R., additional, Horner, Tristan J., additional, Lamborg, Carl H., additional, McCrow, John P., additional, Allen, Andrew E., additional, and Saito, Mak A., additional

Published
2021
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25. Strong margin influence on the Arctic Ocean barium cycle revealed by Pan-Arctic synthesis

Author

Whitmore, Laura M., primary, Shiller, Alan M., additional, Horner, Tristan J, additional, Xiang, Yang, additional, Auro, Maureen E, additional, Bauch, Dorothea, additional, Dehairs, Frank, additional, Lam, Phoebe J., additional, LI, JINGXUAN, additional, Maldonado, Maria Teresa, additional, Mears, Chantal, additional, Newton, Robert, additional, Pasqualini, Angelica, additional, Planquette, Hélène, additional, Rember, Robert, additional, and Thomas, Helmuth, additional

Published
2021
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34. Mechanisms of pelagic barite precipitation

Author

Martínez Ruíz, Francisca C., Paytan, Adina, González Muñoz, M.T., Jroundi, Fadwa, Abad, María del Mar, Lam, P., Bishop, J. K. B., Horner, Tristan J., Morton, Peter L., and Kastner, M.

Subjects
Barite
Abstract

Goldschmidt 2019, Barcelona (Spain), 18th-23th august, 2019

Published
2019

35. Barium-isotopic constraints on the origin of post-Marinoan barites

Author

Crockford, Peter W., primary, Wing, Boswell A., additional, Paytan, Adina, additional, Hodgskiss, Malcolm S.W., additional, Mayfield, Kimberley K., additional, Hayles, Justin A., additional, Middleton, Julia E., additional, Ahm, Anne-Sofie C., additional, Johnston, David T., additional, Caxito, Fabricio, additional, Uhlein, Gabriel, additional, Halverson, Galen P., additional, Eickmann, Benjamin, additional, Torres, Marta, additional, and Horner, Tristan J., additional

Published
2019
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43. Pump it Up workshop report

Author

Buesseler, Ken O., primary, Adams, Allan, additional, Bellingham, James G., additional, Dever, Matthieu, additional, Edgcomb, Virginia P., additional, Estapa, Margaret L., additional, Frank, Alex, additional, Gallager, Scott M., additional, Govindarajan, Annette F., additional, Horner, Tristan J., additional, Hunter, Jon, additional, Jakuba, Michael V., additional, Kapit, Jason, additional, Katija, Kakani, additional, Lawson, Gareth L., additional, Lu, Yuehan, additional, Mahadevan, Amala, additional, Nicholson, David P., additional, Omand, Melissa M., additional, Palevsky, Hilary I., additional, Rauch, Chris, additional, Sosik, Heidi M., additional, Ulmer, Kevin M., additional, Wurgaft, Eyal, additional, and Yoerger, Dana R., additional

Published
2017
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49. A Common Reference Material for Cadmium Isotope Studies - NIST SRM 3108

Author

Abouchami, Wafa, primary, Galer, Stephen J. G., additional, Horner, Tristan J., additional, Rehkämper, Mark, additional, Wombacher, Frank, additional, Xue, Zichen, additional, Lambelet, Myriam, additional, Gault-Ringold, Melanie, additional, Stirling, Claudine H., additional, Schönbächler, Maria, additional, Shiel, Alyssa E., additional, Weis, Dominique, additional, and Holdship, Philip F., additional

Published
2012
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50. A Common Reference Material for Cadmium Isotope Studies - NIST SRM 3108.

Author

Abouchami, Wafa, Galer, Stephen J. G., Horner, Tristan J., Rehkämper, Mark, Wombacher, Frank, Xue, Zichen, Lambelet, Myriam, Gault‐Ringold, Melanie, Stirling, Claudine H., Schönbächler, Maria, Shiel, Alyssa E., Weis, Dominique, and Holdship, Philip F.

Subjects
REFERENCE sources, CADMIUM isotopes, DATA analysis, MASS spectrometry, POLYATOMIC molecules, COMPARATIVE studies, DOPING agents (Chemistry)
Abstract

Copyright of Geostandards & Geoanalytical Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2013
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