Articles | Volume 16, issue 11
https://doi.org/10.5194/bg-16-2247-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-16-2247-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Jun 2019
Research article |
| 04 Jun 2019
| 04 Jun 2019
Seasonality of archaeal lipid flux and GDGT-based thermometry in sinking particles of high-latitude oceans: Fram Strait (79° N) and Antarctic Polar Front (50° S)
Eunmi Park
CORRESPONDING AUTHOR
Alfred Wegener Institute, Helmholtz Center for Polar and Marine
Sciences, 27570 Bremerhaven, Germany
MARUM – Center for Marine Environmental Sciences, University of Bremen, 28334 Bremen, Germany
Department of Geosciences, University of Bremen, 28334 Bremen,
Germany
Jens Hefter
Alfred Wegener Institute, Helmholtz Center for Polar and Marine
Sciences, 27570 Bremerhaven, Germany
Gerhard Fischer
MARUM – Center for Marine Environmental Sciences, University of Bremen, 28334 Bremen, Germany
Department of Geosciences, University of Bremen, 28334 Bremen,
Germany
Morten Hvitfeldt Iversen
Alfred Wegener Institute, Helmholtz Center for Polar and Marine
Sciences, 27570 Bremerhaven, Germany
MARUM – Center for Marine Environmental Sciences, University of Bremen, 28334 Bremen, Germany
Simon Ramondenc
Alfred Wegener Institute, Helmholtz Center for Polar and Marine
Sciences, 27570 Bremerhaven, Germany
MARUM – Center for Marine Environmental Sciences, University of Bremen, 28334 Bremen, Germany
Eva-Maria Nöthig
Alfred Wegener Institute, Helmholtz Center for Polar and Marine
Sciences, 27570 Bremerhaven, Germany
Gesine Mollenhauer
Alfred Wegener Institute, Helmholtz Center for Polar and Marine
Sciences, 27570 Bremerhaven, Germany
MARUM – Center for Marine Environmental Sciences, University of Bremen, 28334 Bremen, Germany
Department of Geosciences, University of Bremen, 28334 Bremen,
Germany
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Bingbing Wei, Guodong Jia, Jens Hefter, Manyu Kang, Eunmi Park, Shizhu Wang, and Gesine Mollenhauer
Biogeosciences, 17, 4489–4508, https://doi.org/10.5194/bg-17-4489-2020, https://doi.org/10.5194/bg-17-4489-2020, 2020
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Jutta E. Wollenburg, Morten Iversen, Christian Katlein, Thomas Krumpen, Marcel Nicolaus, Giulia Castellani, Ilka Peeken, and Hauke Flores
The Cryosphere, 14, 1795–1808, https://doi.org/10.5194/tc-14-1795-2020, https://doi.org/10.5194/tc-14-1795-2020, 2020
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Oscar E. Romero, Karl-Heinz Baumann, Karin A. F. Zonneveld, Barbara Donner, Jens Hefter, Bambaye Hamady, Vera Pospelova, and Gerhard Fischer
Biogeosciences, 17, 187–214, https://doi.org/10.5194/bg-17-187-2020, https://doi.org/10.5194/bg-17-187-2020, 2020
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Thomas Opel, Julian B. Murton, Sebastian Wetterich, Hanno Meyer, Kseniia Ashastina, Frank Günther, Hendrik Grotheer, Gesine Mollenhauer, Petr P. Danilov, Vasily Boeskorov, Grigoriy N. Savvinov, and Lutz Schirrmeister
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Maria-Elena Vorrath, Juliane Müller, Oliver Esper, Gesine Mollenhauer, Christian Haas, Enno Schefuß, and Kirsten Fahl
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Julie Lattaud, Frédérique Kirkels, Francien Peterse, Chantal V. Freymond, Timothy I. Eglinton, Jens Hefter, Gesine Mollenhauer, Sergio Balzano, Laura Villanueva, Marcel T. J. van der Meer, Ellen C. Hopmans, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 15, 4147–4161, https://doi.org/10.5194/bg-15-4147-2018, https://doi.org/10.5194/bg-15-4147-2018, 2018
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Catarina V. Guerreiro, Karl-Heinz Baumann, Geert-Jan A. Brummer, Gerhard Fischer, Laura F. Korte, Ute Merkel, Carolina Sá, Henko de Stigter, and Jan-Berend W. Stuut
Biogeosciences, 14, 4577–4599, https://doi.org/10.5194/bg-14-4577-2017, https://doi.org/10.5194/bg-14-4577-2017, 2017
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Annette Hahn, Enno Schefuß, Sergio Andò, Hayley C. Cawthra, Peter Frenzel, Martin Kugel, Stephanie Meschner, Gesine Mollenhauer, and Matthias Zabel
Clim. Past, 13, 649–665, https://doi.org/10.5194/cp-13-649-2017, https://doi.org/10.5194/cp-13-649-2017, 2017
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Shuwen Sun, Enno Schefuß, Stefan Mulitza, Cristiano M. Chiessi, André O. Sawakuchi, Matthias Zabel, Paul A. Baker, Jens Hefter, and Gesine Mollenhauer
Biogeosciences, 14, 2495–2512, https://doi.org/10.5194/bg-14-2495-2017, https://doi.org/10.5194/bg-14-2495-2017, 2017
Vera D. Meyer, Jens Hefter, Gerrit Lohmann, Lars Max, Ralf Tiedemann, and Gesine Mollenhauer
Clim. Past, 13, 359–377, https://doi.org/10.5194/cp-13-359-2017, https://doi.org/10.5194/cp-13-359-2017, 2017
Anna Belcher, Morten Iversen, Sarah Giering, Virginie Riou, Stephanie A. Henson, Leo Berline, Loic Guilloux, and Richard Sanders
Biogeosciences, 13, 4927–4943, https://doi.org/10.5194/bg-13-4927-2016, https://doi.org/10.5194/bg-13-4927-2016, 2016
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We address the imbalance between the supply and loss of organic carbon to the upper layer of the ocean by measuring a previously poorly quantified term: particle-associated microbial respiration of in situ particles. We find rates that are too low to account for the missing sink of carbon and suggest instead that zooplankton drive the transformation of large fast-sinking particles into slow-sinking and suspended particles. This apparent loss may help explain imbalances in the carbon budget.
Gerhard Fischer, Johannes Karstensen, Oscar Romero, Karl-Heinz Baumann, Barbara Donner, Jens Hefter, Gesine Mollenhauer, Morten Iversen, Björn Fiedler, Ivanice Monteiro, and Arne Körtzinger
Biogeosciences, 13, 3203–3223, https://doi.org/10.5194/bg-13-3203-2016, https://doi.org/10.5194/bg-13-3203-2016, 2016
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Particle fluxes at the Cape Verde Ocean Observatory in the eastern tropical North Atlantic for the period December 2009 until May 2011 are discussed based on deep sediment trap time-series data collected at 1290 and 3439 m water depths. The typically open-ocean flux pattern with weak seasonality is modified by the appearance of a highly productive and low oxygen eddy in winter 2010. The eddy passage was accompanied by high biogenic and lithogenic fluxes, lasting from December 2009 to May 2010.
Gerhard Fischer, Oscar Romero, Ute Merkel, Barbara Donner, Morten Iversen, Nico Nowald, Volker Ratmeyer, Götz Ruhland, Marco Klann, and Gerold Wefer
Biogeosciences, 13, 3071–3090, https://doi.org/10.5194/bg-13-3071-2016, https://doi.org/10.5194/bg-13-3071-2016, 2016
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The studies were initiated to investigate potential changes in the important coastal upwelling system off NW Africa and to evaluate the role of mineral dust for carbon sequestration into the deep ocean. For this purpose, we deployed time series sediment traps in the deep water column off Cape Blanc, Mauritania. A more than two-decadal sediment trap record from this coastal upwelling system is now presented with respect to deep ocean mass fluxes, flux components and their longer term variability.
C. M. Chiessi, S. Mulitza, G. Mollenhauer, J. B. Silva, J. Groeneveld, and M. Prange
Clim. Past, 11, 915–929, https://doi.org/10.5194/cp-11-915-2015, https://doi.org/10.5194/cp-11-915-2015, 2015
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Here we show that temperatures in the western South Atlantic increased markedly during the major slowdown event of the Atlantic meridional overturning circulation (AMOC) of the last deglaciation. Over the adjacent continent, however, temperatures followed the rise in atmospheric carbon dioxide, lagging changes in oceanic temperature. Our records corroborate the notion that the long duration of the major slowdown event of the AMOC was fundamental in driving the Earth out of the last glacial.
M. Winterfeld, T. Laepple, and G. Mollenhauer
Biogeosciences, 12, 3769–3788, https://doi.org/10.5194/bg-12-3769-2015, https://doi.org/10.5194/bg-12-3769-2015, 2015
J. Karstensen, B. Fiedler, F. Schütte, P. Brandt, A. Körtzinger, G. Fischer, R. Zantopp, J. Hahn, M. Visbeck, and D. Wallace
Biogeosciences, 12, 2597–2605, https://doi.org/10.5194/bg-12-2597-2015, https://doi.org/10.5194/bg-12-2597-2015, 2015
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This study is the first report of the formation of dead zones in the open ocean. A combination of multiple ocean observing system elements (mooring, floats, satellites, ships) allowed us to reconstruct the generation of the dead zones and to connect the formation to enhanced respiration within mesoscale ocean eddies. The dead zones present specific threats to the ecosystem, such as the interruption of the diurnal migration of zooplankters.
M. Winterfeld, M. A. Goñi, J. Just, J. Hefter, and G. Mollenhauer
Biogeosciences, 12, 2261–2283, https://doi.org/10.5194/bg-12-2261-2015, https://doi.org/10.5194/bg-12-2261-2015, 2015
A. Cherkasheva, E.-M. Nöthig, E. Bauerfeind, C. Melsheimer, and A. Bracher
Ocean Sci., 9, 431–445, https://doi.org/10.5194/os-9-431-2013, https://doi.org/10.5194/os-9-431-2013, 2013
Related subject area
Paleobiogeoscience: Proxy use, Development & Validation
Deep-sea stylasterid δ18O and δ13C maps inform sampling scheme for paleotemperature reconstructions
A long-term drought reconstruction based on oxygen isotope tree ring data
Mg/Ca and δ18O in multiple species of planktonic foraminifera from 15 Ma to Recent
Disentangling influences of climate variability and lake-system evolution on climate proxies derived from isoprenoid and branched glycerol dialkyl glycerol tetraethers (GDGTs): the 250 kyr Lake Chala record
Electron backscatter diffraction analysis unveils foraminiferal calcite microstructure and processes of diagenetic alteration
Quantifying the δ15N trophic offset in a cold-water scleractinian coral (CWC): implications for the CWC diet and coral δ15N as a marine N cycle proxy
Stable oxygen isotopes of crocodilian tooth enamel allow tracking Plio-Pleistocene evolution of freshwater environments and climate in the Shungura Formation (Turkana Depression, Ethiopia)
Reviews and syntheses: Review of proxies for low-oxygen paleoceanographic reconstructions
Charcoal morphologies and morphometrics of a Eurasian grass-dominated system for robust interpretation of past fuel and fire type
Single-species dinoflagellate cyst carbon isotope fractionation in core-top sediments: environmental controls, CO2 dependency and proxy potential
Past fire dynamics inferred from polycyclic aromatic hydrocarbons and monosaccharide anhydrides in a stalagmite from the archaeological site of Mayapan, Mexico
Examination of the parameters controlling the triple oxygen isotope composition of grass leaf water and phytoliths at a Mediterranean site: a model–data approach
Biomarker characterization of the North Water Polynya, Baffin Bay: implications for local sea ice and temperature proxies
Technical note: No impact of alkenone extraction on foraminiferal stable isotope, trace element and boron isotope geochemistry
Experimental burial diagenesis of aragonitic biocarbonates: from organic matter loss to abiogenic calcite formation
A modern snapshot of the isotopic composition of lacustrine biogenic carbonates – records of seasonal water temperature variability
Performance of temperature and productivity proxies based on long-chain alkane-1, mid-chain diols at test: a 5-year sediment trap record from the Mauritanian upwelling
Validation of a coupled δ2Hn-alkane–δ18Osugar paleohygrometer approach based on a climate chamber experiment
Experimental production of charcoal morphologies to discriminate fuel source and fire type: an example from Siberian taiga
Toward a global calibration for quantifying past oxygenation in oxygen minimum zones using benthic Foraminifera
Calibration of Mg ∕ Ca and Sr ∕ Ca in coastal marine ostracods as a proxy for temperature
Technical note: Accelerate coccolith size separation via repeated centrifugation
Mg∕Ca, Sr∕Ca and stable isotopes from the planktonic foraminifera T. sacculifer: testing a multi-proxy approach for inferring paleotemperature and paleosalinity
Chemical destaining and the delta correction for blue intensity measurements of stained lake subfossil trees
Modern calibration of Poa flabellata (tussac grass) as a new paleoclimate proxy in the South Atlantic
Seawater pH reconstruction using boron isotopes in multiple planktonic foraminifera species with different depth habitats and their potential to constrain pH and pCO2 gradients
Bottom-water deoxygenation at the Peruvian margin during the last deglaciation recorded by benthic foraminifera
The pH dependency of the boron isotopic composition of diatom opal (Thalassiosira weissflogii)
Benthic foraminifera as tracers of brine production in the Storfjorden “sea ice factory”
Evaluation of bacterial glycerol dialkyl glycerol tetraether and 2H–18O biomarker proxies along a central European topsoil transect
Leaf wax n-alkane patterns and compound-specific δ13C of plants and topsoils from semi-arid and arid Mongolia
Organic-carbon-rich sediments: benthic foraminifera as bio-indicators of depositional environments
Strong correspondence between nitrogen isotope composition of foliage and chlorin across a rainfall gradient: implications for paleo-reconstruction of the nitrogen cycle
Environmental and biological controls on Na∕Ca ratios in scleractinian cold-water corals
Depth habitat of the planktonic foraminifera Neogloboquadrina pachyderma in the northern high latitudes explained by sea-ice and chlorophyll concentrations
Temporal variability in foraminiferal morphology and geochemistry at the West Antarctic Peninsula: a sediment trap study
Long-chain diols in settling particles in tropical oceans: insights into sources, seasonality and proxies
Multi-trace-element sea surface temperature coral reconstruction for the southern Mozambique Channel reveals teleconnections with the tropical Atlantic
Oxygen isotope composition of the final chamber of planktic foraminifera provides evidence of vertical migration and depth-integrated growth
Mg ∕ Ca and δ18O in living planktic foraminifers from the Caribbean, Gulf of Mexico and Florida Straits
Manganese incorporation in living (stained) benthic foraminiferal shells: a bathymetric and in-sediment study in the Gulf of Lions (NW Mediterranean)
Effects of light and temperature on Mg uptake, growth, and calcification in the proxy climate archive Clathromorphum compactum
A systematic look at chromium isotopes in modern shells – implications for paleo-environmental reconstructions
Reviews and syntheses: Revisiting the boron systematics of aragonite and their application to coral calcification
Physico-chemical and biological factors influencing dinoflagellate cyst production in the Cariaco Basin
Effects of alkalinity and salinity at low and high light intensity on hydrogen isotope fractionation of long-chain alkenones produced by Emiliania huxleyi
Interplay of community dynamics, temperature, and productivity on the hydrogen isotope signatures of lipid biomarkers
Benthic foraminiferal Mn / Ca ratios reflect microhabitat preferences
The effects of environment on Arctica islandica shell formation and architecture
Diatoms as a paleoproductivity proxy in the NW Iberian coastal upwelling system (NE Atlantic)
Theresa M. King, Brad E. Rosenheim, and Noel P. James
Biogeosciences, 21, 5361–5379, https://doi.org/10.5194/bg-21-5361-2024, https://doi.org/10.5194/bg-21-5361-2024, 2024
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Corals can record ocean properties such as temperature in their skeletons. These records are useful for where and when we have no instrumental record like in the distant past. However, coral growth must be understood to interpret these records. Here, we analyze slices of a branching deep-sea coral from Antarctica to determine how to best sample these corals for past-climate work. We recommend sampling from the innermost portion of a coral skeleton for accurate temperature reconstructions.
Viorica Nagavciuc, Gerhard Helle, Maria Rădoane, Cătălin-Constantin Roibu, Mihai-Gabriel Cotos, and Monica Ionita
EGUsphere, https://doi.org/10.5194/egusphere-2024-2144, https://doi.org/10.5194/egusphere-2024-2144, 2024
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We reconstructed drought conditions for the past 200 years using δ18O in oak tree ring cellulose from Romania, revealing periods of both extreme wetness (e.g., 1905–1915) and dryness (e.g., 1818–1835). The most severe droughts occurred in the 19th and 21st centuries. The study suggests a connection between drought patterns and large-scale atmospheric circulation. This research highlights the potential of tree rings to improve our understanding of long-term climate variability in Europe.
Flavia Boscolo-Galazzo, David Evans, Elaine Mawbey, William Gray, Paul Pearson, and Bridget Wade
EGUsphere, https://doi.org/10.5194/egusphere-2024-1608, https://doi.org/10.5194/egusphere-2024-1608, 2024
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Here we present a comparison of results from the Mg/Ca and oxygen stable isotopes paleothermometers obtained from 57 modern to fossil species of planktonic foraminifera from the last 15 million of years. We find that the occurrence (or not) of species-species offsets in Mg/Ca is conservative between ancestor-descendent species, and that taking into account species kinship can significantly improve temperature reconstructions by several degrees.
Allix J. Baxter, Francien Peterse, Dirk Verschuren, Aihemaiti Maitituerdi, Nicolas Waldmann, and Jaap S. Sinninghe Damsté
Biogeosciences, 21, 2877–2908, https://doi.org/10.5194/bg-21-2877-2024, https://doi.org/10.5194/bg-21-2877-2024, 2024
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This study investigates the impact of long-term lake-system evolution on the climate signal recorded by glycerol dialkyl glycerol tetraethers (GDGTs), a popular biomarker in paleoclimate research. It compares downcore changes in GDGTs in the 250 000 year sediment sequence of Lake Chala (Kenya/Tanzania) to independent data for lake mixing and water-column chemistry. These factors influence the GDGT proxies in the earliest depositional phases (before ~180 ka), confounding the climate signal.
Frances A. Procter, Sandra Piazolo, Eleanor H. John, Richard Walshaw, Paul N. Pearson, Caroline H. Lear, and Tracy Aze
Biogeosciences, 21, 1213–1233, https://doi.org/10.5194/bg-21-1213-2024, https://doi.org/10.5194/bg-21-1213-2024, 2024
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This study uses novel techniques to look at the microstructure of planktonic foraminifera (single-celled marine organisms) fossils, to further our understanding of how they form their hard exterior shells and how the microstructure and chemistry of these shells can change as a result of processes that occur after deposition on the seafloor. Understanding these processes is of critical importance for using planktonic foraminifera for robust climate and environmental reconstructions of the past.
Josie L. Mottram, Anne M. Gothmann, Maria G. Prokopenko, Austin Cordova, Veronica Rollinson, Katie Dobkowski, and Julie Granger
Biogeosciences, 21, 1071–1091, https://doi.org/10.5194/bg-21-1071-2024, https://doi.org/10.5194/bg-21-1071-2024, 2024
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Knowledge of ancient ocean N cycling can help illuminate past climate change. Using field and lab studies, this work ground-truths a promising proxy for marine N cycling, the N isotope composition of cold-water coral (CWC) skeletons. Our results estimate N turnover in CWC tissue; quantify the isotope effects between CWC tissue, diet, and skeleton; and suggest that CWCs possibly feed mainly on metazoan zooplankton, suggesting that the marine N proxy may be sensitive to the food web structure.
Axelle Gardin, Emmanuelle Pucéat, Géraldine Garcia, Jean-Renaud Boisserie, Adélaïde Euriat, Michael M. Joachimski, Alexis Nutz, Mathieu Schuster, and Olga Otero
Biogeosciences, 21, 437–454, https://doi.org/10.5194/bg-21-437-2024, https://doi.org/10.5194/bg-21-437-2024, 2024
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We introduce a novel approach using stable oxygen isotopes from crocodilian fossil teeth to unravel palaeohydrological changes in past continental contexts. Applying it to the Plio-Pleistocene Ethiopian Shungura Formation, we found a significant increase in δ18O in the last 3 million years, likely due to monsoonal shifts and reduced rainfall, and that the local diversity of waterbodies (lakes, rivers, ponds) became restricted.
Babette Hoogakker, Catherine Davis, Yi Wang, Stepanie Kusch, Katrina Nilsson-Kerr, Dalton Hardisty, Allison Jacobel, Dharma Reyes Macaya, Nicolaas Glock, Sha Ni, Julio Sepúlveda, Abby Ren, Alexandra Auderset, Anya Hess, Katrina Meissner, Jorge Cardich, Robert Anderson, Christine Barras, Chandranath Basak, Harold Bradbury, Inda Brinkmann, Alexis Castillo, Madelyn Cook, Kassandra Costa, Constance Choquel, Paula Diz, Jonas Donnenfield, Felix Elling, Zeynep Erdem, Helena Filipsson, Sebastian Garrido, Julia Gottschalk, Anjaly Govindankutty Menon, Jeroen Groeneveld, Christian Hallman, Ingrid Hendy, Rick Hennekam, Wanyi Lu, Jean Lynch-Stieglitz, Lelia Matos, Alfredo Martínez-García, Giulia Molina, Práxedes Muñoz, Simone Moretti, Jennifer Morford, Sophie Nuber, Svetlana Radionovskaya, Morgan Raven, Christopher Somes, Anja Studer, Kazuyo Tachikawa, Raúl Tapia, Martin Tetard, Tyler Vollmer, Shuzhuang Wu, Yan Zhang, Xin-Yuan Zheng, and Yuxin Zhou
EGUsphere, https://doi.org/10.5194/egusphere-2023-2981, https://doi.org/10.5194/egusphere-2023-2981, 2024
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Paleo-oxygen proxies can extend current records, bound pre-anthropogenic baselines, provide datasets necessary to test climate models under different boundary conditions, and ultimately understand how ocean oxygenation responds on longer timescales. Here we summarize current proxies used for the reconstruction of Cenozoic seawater oxygen levels. This includes an overview of the proxy's history, how it works, resources required, limitations, and future recommendations.
Angelica Feurdean, Richard S. Vachula, Diana Hanganu, Astrid Stobbe, and Maren Gumnior
Biogeosciences, 20, 5069–5085, https://doi.org/10.5194/bg-20-5069-2023, https://doi.org/10.5194/bg-20-5069-2023, 2023
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This paper presents novel results of laboratory-produced charcoal forms from various grass, forb and shrub taxa from the Eurasian steppe to facilitate more robust interpretations of fuel sources and fire types in grassland-dominated ecosystems. Advancements in identifying fuel sources and changes in fire types make charcoal analysis relevant to studies of plant evolution and fire management.
Joost Frieling, Linda van Roij, Iris Kleij, Gert-Jan Reichart, and Appy Sluijs
Biogeosciences, 20, 4651–4668, https://doi.org/10.5194/bg-20-4651-2023, https://doi.org/10.5194/bg-20-4651-2023, 2023
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We present a first species-specific evaluation of marine core-top dinoflagellate cyst carbon isotope fractionation (εp) to assess natural pCO2 dependency on εp and explore its geological deep-time paleo-pCO2 proxy potential. We find that εp differs between genera and species and that in Operculodinium centrocarpum, εp is controlled by pCO2 and nutrients. Our results highlight the added value of δ13C analyses of individual micrometer-scale sedimentary organic carbon particles.
Julia Homann, Niklas Karbach, Stacy A. Carolin, Daniel H. James, David Hodell, Sebastian F. M. Breitenbach, Ola Kwiecien, Mark Brenner, Carlos Peraza Lope, and Thorsten Hoffmann
Biogeosciences, 20, 3249–3260, https://doi.org/10.5194/bg-20-3249-2023, https://doi.org/10.5194/bg-20-3249-2023, 2023
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Cave stalagmites contain substances that can be used to reconstruct past changes in local and regional environmental conditions. We used two classes of biomarkers (polycyclic aromatic hydrocarbons and monosaccharide anhydrides) to detect the presence of fire and to also explore changes in fire regime (e.g. fire frequency, intensity, and fuel source). We tested our new method on a stalagmite from Mayapan, a large Maya city on the Yucatán Peninsula.
Claudia Voigt, Anne Alexandre, Ilja M. Reiter, Jean-Philippe Orts, Christine Vallet-Coulomb, Clément Piel, Jean-Charles Mazur, Julie C. Aleman, Corinne Sonzogni, Helene Miche, and Jérôme Ogée
Biogeosciences, 20, 2161–2187, https://doi.org/10.5194/bg-20-2161-2023, https://doi.org/10.5194/bg-20-2161-2023, 2023
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Data on past relative humidity (RH) ARE needed to improve its representation in Earth system models. A novel isotope parameter (17O-excess) of plant silica has been developed to quantify past RH. Using comprehensive monitoring and novel methods, we show how environmental and plant physiological parameters influence the 17O-excess of plant silica and leaf water, i.e. its source water. The insights gained from this study will help to improve estimates of RH from fossil plant silica deposits.
David J. Harning, Brooke Holman, Lineke Woelders, Anne E. Jennings, and Julio Sepúlveda
Biogeosciences, 20, 229–249, https://doi.org/10.5194/bg-20-229-2023, https://doi.org/10.5194/bg-20-229-2023, 2023
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In order to better reconstruct the geologic history of the North Water Polynya, we provide modern validations and calibrations of lipid biomarker proxies in Baffin Bay. We find that sterols, rather than HBIs, most accurately capture the current extent of the North Water Polynya and will be a valuable tool to reconstruct its past presence or absence. Our local temperature calibrations for GDGTs and OH-GDGTs reduce the uncertainty present in global temperature calibrations.
Jessica G. M. Crumpton-Banks, Thomas Tanner, Ivan Hernández Almeida, James W. B. Rae, and Heather Stoll
Biogeosciences, 19, 5633–5644, https://doi.org/10.5194/bg-19-5633-2022, https://doi.org/10.5194/bg-19-5633-2022, 2022
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Past ocean carbon is reconstructed using proxies, but it is unknown whether preparing ocean sediment for one proxy might damage the data given by another. We have tested whether the extraction of an organic proxy archive from sediment samples impacts the geochemistry of tiny shells also within the sediment. We find no difference in shell geochemistry between samples which come from treated and untreated sediment. This will help us to maximize scientific return from valuable sediment samples.
Pablo Forjanes, María Simonet Roda, Martina Greiner, Erika Griesshaber, Nelson A. Lagos, Sabino Veintemillas-Verdaguer, José Manuel Astilleros, Lurdes Fernández-Díaz, and Wolfgang W. Schmahl
Biogeosciences, 19, 3791–3823, https://doi.org/10.5194/bg-19-3791-2022, https://doi.org/10.5194/bg-19-3791-2022, 2022
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Aragonitic skeletons are employed to decipher past climate dynamics and environmental change. Unfortunately, the information that these skeletons keep can be destroyed during diagenesis. In this work, we study the first changes undergone by aragonitic skeletons upon hydrothermal alteration. We observe that major changes occur from the very beginning of the alteration, even without mineralogical changes. These results have major implications for the use of these archives to understand the past.
Inga Labuhn, Franziska Tell, Ulrich von Grafenstein, Dan Hammarlund, Henning Kuhnert, and Bénédicte Minster
Biogeosciences, 19, 2759–2777, https://doi.org/10.5194/bg-19-2759-2022, https://doi.org/10.5194/bg-19-2759-2022, 2022
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This study presents the isotopic composition of recent biogenic carbonates from several lacustrine species which calcify during different times of the year. The authors demonstrate that when biological offsets are corrected, the dominant cause of differences between species is the seasonal variation in temperature-dependent fractionation of oxygen isotopes. Consequently, such carbonates from lake sediments can provide proxy records of seasonal water temperature changes in the past.
Gerard J. M. Versteegh, Karin A. F. Zonneveld, Jens Hefter, Oscar E. Romero, Gerhard Fischer, and Gesine Mollenhauer
Biogeosciences, 19, 1587–1610, https://doi.org/10.5194/bg-19-1587-2022, https://doi.org/10.5194/bg-19-1587-2022, 2022
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A 5-year record of long-chain mid-chain diol export flux and composition is presented with a 1- to 3-week resolution sediment trap CBeu (in the NW African upwelling). All environmental parameters as well as the diol composition are dominated by the seasonal cycle, albeit with different phase relations for temperature and upwelling. Most diol-based proxies are dominated by upwelling. The long-chain diol index reflects temperatures of the oligotrophic summer sea surface.
Johannes Hepp, Christoph Mayr, Kazimierz Rozanski, Imke Kathrin Schäfer, Mario Tuthorn, Bruno Glaser, Dieter Juchelka, Willibald Stichler, Roland Zech, and Michael Zech
Biogeosciences, 18, 5363–5380, https://doi.org/10.5194/bg-18-5363-2021, https://doi.org/10.5194/bg-18-5363-2021, 2021
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Deriving more quantitative climate information like relative air humidity is one of the key challenges in paleostudies. Often only qualitative reconstructions can be done when single-biomarker-isotope data are derived from a climate archive. However, the coupling of hemicellulose-derived sugar with leaf-wax-derived n-alkane isotope results has the potential to overcome this limitation and allow a quantitative relative air humidity reconstruction.
Angelica Feurdean
Biogeosciences, 18, 3805–3821, https://doi.org/10.5194/bg-18-3805-2021, https://doi.org/10.5194/bg-18-3805-2021, 2021
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This study characterized the diversity of laboratory-produced charcoal morphological features of various fuel types from Siberia at different temperatures. The results obtained improve the attribution of charcoal particles to fuel types and fire characteristics. This work also provides recommendations for the application of this information to refine the past wildfire history.
Martin Tetard, Laetitia Licari, Ekaterina Ovsepyan, Kazuyo Tachikawa, and Luc Beaufort
Biogeosciences, 18, 2827–2841, https://doi.org/10.5194/bg-18-2827-2021, https://doi.org/10.5194/bg-18-2827-2021, 2021
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Oxygen minimum zones are oceanic regions almost devoid of dissolved oxygen and are currently expanding due to global warming. Investigation of their past behaviour will allow better understanding of these areas and better prediction of their future evolution. A new method to estimate past [O2] was developed based on morphometric measurements of benthic foraminifera. This method and two other approaches based on foraminifera assemblages and porosity were calibrated using 45 core tops worldwide.
Maximiliano Rodríguez and Christelle Not
Biogeosciences, 18, 1987–2001, https://doi.org/10.5194/bg-18-1987-2021, https://doi.org/10.5194/bg-18-1987-2021, 2021
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Mg/Ca in calcium carbonate shells of marine organisms such as foraminifera and ostracods has been used as a proxy to reconstruct water temperature. Here we provide new Mg/Ca–temperature calibrations for two shallow marine species of ostracods. We show that the water temperature in spring produces the best calibrations, which suggests the potential use of ostracod shells to reconstruct this parameter at a seasonal scale.
Hongrui Zhang, Chuanlian Liu, Luz María Mejía, and Heather Stoll
Biogeosciences, 18, 1909–1916, https://doi.org/10.5194/bg-18-1909-2021, https://doi.org/10.5194/bg-18-1909-2021, 2021
Delphine Dissard, Gert Jan Reichart, Christophe Menkes, Morgan Mangeas, Stephan Frickenhaus, and Jelle Bijma
Biogeosciences, 18, 423–439, https://doi.org/10.5194/bg-18-423-2021, https://doi.org/10.5194/bg-18-423-2021, 2021
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Results from a data set acquired from living foraminifera T. sacculifer collected from surface waters are presented, allowing us to establish a new Mg/Ca–Sr/Ca–temperature equation improving temperature reconstructions. When combining equations, δ18Ow can be reconstructed with a precision of ± 0.5 ‰, while successive reconstructions involving Mg/Ca and δ18Oc preclude salinity reconstruction with a precision better than ± 1.69. A new direct linear fit to reconstruct salinity could be established.
Feng Wang, Dominique Arseneault, Étienne Boucher, Shulong Yu, Steeven Ouellet, Gwenaëlle Chaillou, Ann Delwaide, and Lily Wang
Biogeosciences, 17, 4559–4570, https://doi.org/10.5194/bg-17-4559-2020, https://doi.org/10.5194/bg-17-4559-2020, 2020
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Wood stain is challenging the use of the blue intensity technique for dendroclimatic reconstructions. Using stained subfossil trees from eastern Canadian lakes, we compared chemical destaining approaches with the
delta bluemathematical correction of blue intensity data. Although no chemical treatment was completely efficient, the delta blue method is unaffected by the staining problem and thus is promising for climate reconstructions based on lake subfossil material.
Dulcinea V. Groff, David G. Williams, and Jacquelyn L. Gill
Biogeosciences, 17, 4545–4557, https://doi.org/10.5194/bg-17-4545-2020, https://doi.org/10.5194/bg-17-4545-2020, 2020
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Tussock grasses that grow along coastlines of the Falkland Islands are slow to decay and build up thick peat layers over thousands of years. Grass fragments found in ancient peat can be used to reconstruct past climate because grasses can preserve a record of growing conditions in their leaves. We found that modern living tussock grasses in the Falkland Islands reliably record temperature and humidity in their leaves, and the peat they form can be used to understand past climate change.
Maxence Guillermic, Sambuddha Misra, Robert Eagle, Alexandra Villa, Fengming Chang, and Aradhna Tripati
Biogeosciences, 17, 3487–3510, https://doi.org/10.5194/bg-17-3487-2020, https://doi.org/10.5194/bg-17-3487-2020, 2020
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Boron isotope ratios (δ11B) of foraminifera are a promising proxy for seawater pH and can be used to constrain pCO2. In this study, we derived calibrations for new foraminiferal taxa which extend the application of the boron isotope proxy. We discuss the origin of different δ11B signatures in species and also discuss the potential of using multispecies δ11B analyses to constrain vertical pH and pCO2 gradients in ancient water columns to shed light on biogeochemical carbon cycling in the past.
Zeynep Erdem, Joachim Schönfeld, Anthony E. Rathburn, Maria-Elena Pérez, Jorge Cardich, and Nicolaas Glock
Biogeosciences, 17, 3165–3182, https://doi.org/10.5194/bg-17-3165-2020, https://doi.org/10.5194/bg-17-3165-2020, 2020
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Recent observations from today’s oceans revealed that oxygen concentrations are decreasing, and oxygen minimum zones are expanding together with current climate change. With the aim of understanding past climatic events and their relationship with oxygen content, we looked at the fossils, called benthic foraminifera, preserved in the sediment archives from the Peruvian margin and quantified the bottom-water oxygen content for the last 22 000 years.
Hannah K. Donald, Gavin L. Foster, Nico Fröhberg, George E. A. Swann, Alex J. Poulton, C. Mark Moore, and Matthew P. Humphreys
Biogeosciences, 17, 2825–2837, https://doi.org/10.5194/bg-17-2825-2020, https://doi.org/10.5194/bg-17-2825-2020, 2020
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The boron isotope pH proxy is increasingly being used to reconstruct ocean pH in the past. Here we detail a novel analytical methodology for measuring the boron isotopic composition (δ11B) of diatom opal and apply this to the study of the diatom Thalassiosira weissflogii grown in culture over a range of pH. To our knowledge this is the first study of its kind and provides unique insights into the way in which diatoms incorporate boron and their potential as archives of palaeoclimate records.
Eleonora Fossile, Maria Pia Nardelli, Arbia Jouini, Bruno Lansard, Antonio Pusceddu, Davide Moccia, Elisabeth Michel, Olivier Péron, Hélène Howa, and Meryem Mojtahid
Biogeosciences, 17, 1933–1953, https://doi.org/10.5194/bg-17-1933-2020, https://doi.org/10.5194/bg-17-1933-2020, 2020
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This study focuses on benthic foraminiferal distribution in an Arctic fjord characterised by continuous sea ice production during winter and the consequent cascading of salty and corrosive waters (brine) to the seabed. The inner fjord is dominated by calcareous species (C). In the central deep basins, where brines are persistent, calcareous foraminifera are dissolved and agglutinated (A) dominate. The high A/C ratio is suggested as a proxy for brine persistence and sea ice production.
Johannes Hepp, Imke Kathrin Schäfer, Verena Lanny, Jörg Franke, Marcel Bliedtner, Kazimierz Rozanski, Bruno Glaser, Michael Zech, Timothy Ian Eglinton, and Roland Zech
Biogeosciences, 17, 741–756, https://doi.org/10.5194/bg-17-741-2020, https://doi.org/10.5194/bg-17-741-2020, 2020
Julian Struck, Marcel Bliedtner, Paul Strobel, Jens Schumacher, Enkhtuya Bazarradnaa, and Roland Zech
Biogeosciences, 17, 567–580, https://doi.org/10.5194/bg-17-567-2020, https://doi.org/10.5194/bg-17-567-2020, 2020
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We present leaf wax n-alkanes and their compound-specific (CS) δ13C isotopes from semi-arid and/or arid Mongolia to test their potential for paleoenvironmental reconstructions. Plants and topsoils were analysed and checked for climatic control. Chain-length variations are distinct between grasses and Caragana, which are not biased by climate. However CS δ13C is strongly correlated to climate, so n-alkanes and their CS δ13C show great potential for paleoenvironmental reconstruction in Mongolia.
Elena Lo Giudice Cappelli, Jessica Louise Clarke, Craig Smeaton, Keith Davidson, and William Edward Newns Austin
Biogeosciences, 16, 4183–4199, https://doi.org/10.5194/bg-16-4183-2019, https://doi.org/10.5194/bg-16-4183-2019, 2019
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Fjords are known sinks of organic carbon (OC); however, little is known about the long-term fate of the OC stored in these sediments. The reason for this knowledge gap is the post-depositional degradation of OC. This study uses benthic foraminifera (microorganisms with calcite shells) to discriminate between post-depositional OC degradation and actual OC burial and accumulation in fjordic sediments, as foraminifera would only preserve the latter information in their assemblage composition.
Sara K. E. Goulden, Naohiko Ohkouchi, Katherine H. Freeman, Yoshito Chikaraishi, Nanako O. Ogawa, Hisami Suga, Oliver Chadwick, and Benjamin Z. Houlton
Biogeosciences, 16, 3869–3882, https://doi.org/10.5194/bg-16-3869-2019, https://doi.org/10.5194/bg-16-3869-2019, 2019
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We investigate whether soil organic compounds preserve information about nitrogen availability to plants. We isolate chlorophyll degradation products in leaves, litter, and soil and explore possible species and climate effects on preservation and interpretation. We find that compound-specific nitrogen isotope measurements in soil have potential as a new tool to reconstruct changes in nitrogen cycling on a landscape over time, avoiding issues that have limited other proxies.
Nicolai Schleinkofer, Jacek Raddatz, André Freiwald, David Evans, Lydia Beuck, Andres Rüggeberg, and Volker Liebetrau
Biogeosciences, 16, 3565–3582, https://doi.org/10.5194/bg-16-3565-2019, https://doi.org/10.5194/bg-16-3565-2019, 2019
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In this study we tried to correlate Na / Ca ratios from cold-water corals with environmental parameters such as salinity, temperature and pH. We do not observe a correlation between Na / Ca ratios and seawater salinity, but we do observe a strong correlation with temperature. Na / Ca data from warm-water corals (Porites spp.) and bivalves (Mytilus edulis) support this correlation, indicating that similar controls on the incorporation of sodium exist in these aragonitic organisms.
Mattia Greco, Lukas Jonkers, Kerstin Kretschmer, Jelle Bijma, and Michal Kucera
Biogeosciences, 16, 3425–3437, https://doi.org/10.5194/bg-16-3425-2019, https://doi.org/10.5194/bg-16-3425-2019, 2019
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To be able to interpret the paleoecological signal contained in N. pachyderma's shells, its habitat depth must be known. Our investigation on 104 density profiles of this species from the Arctic and North Atlantic shows that specimens reside closer to the surface when sea-ice and/or surface chlorophyll concentrations are high. This is in contrast with previous investigations that pointed at the position of the deep chlorophyll maximum as the main driver of N. pachyderma vertical distribution.
Anna Mikis, Katharine R. Hendry, Jennifer Pike, Daniela N. Schmidt, Kirsty M. Edgar, Victoria Peck, Frank J. C. Peeters, Melanie J. Leng, Michael P. Meredith, Chloe L. C. Jones, Sharon Stammerjohn, and Hugh Ducklow
Biogeosciences, 16, 3267–3282, https://doi.org/10.5194/bg-16-3267-2019, https://doi.org/10.5194/bg-16-3267-2019, 2019
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Antarctic marine calcifying organisms are threatened by regional climate change and ocean acidification. Future projections of regional carbonate production are challenging due to the lack of historical data combined with complex climate variability. We present a 6-year record of flux, morphology and geochemistry of an Antarctic planktonic foraminifera, which shows that their growth is most sensitive to sea ice dynamics and is linked with the El Niño–Southern Oscillation.
Marijke W. de Bar, Jenny E. Ullgren, Robert C. Thunnell, Stuart G. Wakeham, Geert-Jan A. Brummer, Jan-Berend W. Stuut, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 16, 1705–1727, https://doi.org/10.5194/bg-16-1705-2019, https://doi.org/10.5194/bg-16-1705-2019, 2019
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We analyzed sediment traps from the Cariaco Basin, the tropical Atlantic and the Mozambique Channel to evaluate seasonal imprints in the concentrations and fluxes of long-chain diols (LDIs), in addition to the long-chain diol index proxy (sea surface temperature proxy) and the diol index (upwelling indicator). Despite significant degradation, LDI-derived temperatures were very similar for the sediment traps and seafloor sediments, and corresponded to annual mean sea surface temperatures.
Jens Zinke, Juan P. D'Olivo, Christoph J. Gey, Malcolm T. McCulloch, J. Henrich Bruggemann, Janice M. Lough, and Mireille M. M. Guillaume
Biogeosciences, 16, 695–712, https://doi.org/10.5194/bg-16-695-2019, https://doi.org/10.5194/bg-16-695-2019, 2019
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Here we report seasonally resolved sea surface temperature (SST) reconstructions for the southern Mozambique Channel in the SW Indian Ocean, a region located along the thermohaline ocean surface circulation route, based on multi-trace-element temperature proxy records preserved in two Porites sp. coral cores for the past 42 years. Particularly, we show the suitability of both separate and combined Sr / Ca and Li / Mg proxies for improved multielement SST reconstructions.
Hilde Pracht, Brett Metcalfe, and Frank J. C. Peeters
Biogeosciences, 16, 643–661, https://doi.org/10.5194/bg-16-643-2019, https://doi.org/10.5194/bg-16-643-2019, 2019
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In palaeoceanography the shells of single-celled foraminifera are routinely used as proxies to reconstruct the temperature, salinity and circulation of the ocean in the past. Traditionally a number of specimens were pooled for a single stable isotope measurement; however, technical advances now mean that a single shell or chamber of a shell can be measured individually. Three different hypotheses regarding foraminiferal biology and ecology were tested using this approach.
Anna Jentzen, Dirk Nürnberg, Ed C. Hathorne, and Joachim Schönfeld
Biogeosciences, 15, 7077–7095, https://doi.org/10.5194/bg-15-7077-2018, https://doi.org/10.5194/bg-15-7077-2018, 2018
Shauna Ní Fhlaithearta, Christophe Fontanier, Frans Jorissen, Aurélia Mouret, Adriana Dueñas-Bohórquez, Pierre Anschutz, Mattias B. Fricker, Detlef Günther, Gert J. de Lange, and Gert-Jan Reichart
Biogeosciences, 15, 6315–6328, https://doi.org/10.5194/bg-15-6315-2018, https://doi.org/10.5194/bg-15-6315-2018, 2018
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This study looks at how foraminifera interact with their geochemical environment in the seabed. We focus on the incorporation of the trace metal manganese (Mn), with the aim of developing a tool to reconstruct past pore water profiles. Manganese concentrations in foraminifera are investigated relative to their ecological preferences and geochemical environment. This study demonstrates that Mn in foraminiferal tests is a promising tool to reconstruct oxygen conditions in the seabed.
Siobhan Williams, Walter Adey, Jochen Halfar, Andreas Kronz, Patrick Gagnon, David Bélanger, and Merinda Nash
Biogeosciences, 15, 5745–5759, https://doi.org/10.5194/bg-15-5745-2018, https://doi.org/10.5194/bg-15-5745-2018, 2018
Robert Frei, Cora Paulukat, Sylvie Bruggmann, and Robert M. Klaebe
Biogeosciences, 15, 4905–4922, https://doi.org/10.5194/bg-15-4905-2018, https://doi.org/10.5194/bg-15-4905-2018, 2018
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The reconstruction of paleo-redox conditions of seawater has the potential to link to climatic changes on land and therefore to contribute to our understanding of past climate change. The redox-sensitive chromium isotope system is applied to marine calcifiers in order to characterize isotope offsets that result from vital processes during calcification processes and which can be eventually used in fossil equivalents to reconstruct past seawater compositions.
Thomas M. DeCarlo, Michael Holcomb, and Malcolm T. McCulloch
Biogeosciences, 15, 2819–2834, https://doi.org/10.5194/bg-15-2819-2018, https://doi.org/10.5194/bg-15-2819-2018, 2018
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Understanding the mechanisms of coral calcification is limited by the isolation of the calcifying environment. The boron systematics (B / Ca and δ11B) of aragonite have recently been developed as a proxy for the carbonate chemistry of the calcifying fluid, but a variety of approaches have been utilized. We assess the available experimental B / Ca partitioning data and present a computer code for deriving calcifying fluid carbonate chemistry from the boron systematics of coral skeletons.
Manuel Bringué, Robert C. Thunell, Vera Pospelova, James L. Pinckney, Oscar E. Romero, and Eric J. Tappa
Biogeosciences, 15, 2325–2348, https://doi.org/10.5194/bg-15-2325-2018, https://doi.org/10.5194/bg-15-2325-2018, 2018
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We document 2.5 yr of dinoflagellate cyst production in the Cariaco Basin using a sediment trap record. Each species' production pattern is interpreted in the context of the physico-chemical (e.g., temperature, nutrients) and biological (other planktonic groups) environment. Most species respond positively to upwelling, but seem to be negatively impacted by an El Niño event with a 1-year lag. This work helps understanding dinoflagellate ecology and interpreting fossil assemblages in sediments.
Gabriella M. Weiss, Eva Y. Pfannerstill, Stefan Schouten, Jaap S. Sinninghe Damsté, and Marcel T. J. van der Meer
Biogeosciences, 14, 5693–5704, https://doi.org/10.5194/bg-14-5693-2017, https://doi.org/10.5194/bg-14-5693-2017, 2017
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Algal-derived compounds allow us to make assumptions about environmental conditions in the past. In order to better understand how organisms record environmental conditions, we grew microscopic marine algae at different light intensities, salinities, and alkalinities in a temperature-controlled environment. We determined how these environmental parameters affected specific algal-derived compounds, especially their relative deuterium content, which seems to be mainly affected by salinity.
S. Nemiah Ladd, Nathalie Dubois, and Carsten J. Schubert
Biogeosciences, 14, 3979–3994, https://doi.org/10.5194/bg-14-3979-2017, https://doi.org/10.5194/bg-14-3979-2017, 2017
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Hydrogen isotopes of lipids provide valuable information about microbial activity, climate, and environmental stress. We show that heavy hydrogen in fatty acids declines from spring to summer in a nutrient-rich and a nutrient-poor lake and that the effect is nearly 3 times as big in the former. This effect is likely a combination of increased biomass from algae, warmer temperatures, and higher algal growth rates.
Karoliina A. Koho, Lennart J. de Nooijer, Christophe Fontanier, Takashi Toyofuku, Kazumasa Oguri, Hiroshi Kitazato, and Gert-Jan Reichart
Biogeosciences, 14, 3067–3082, https://doi.org/10.5194/bg-14-3067-2017, https://doi.org/10.5194/bg-14-3067-2017, 2017
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Here we report Mn / Ca ratios in living benthic foraminifera from the NE Japan margin. The results show that the Mn incorporation directly reflects the environment where the foraminifera calcify. Foraminifera that live deeper in sediment, under greater redox stress, generally incorporate more Mn into their carbonate skeletons. As such, foraminifera living close to the Mn reduction zone in sediment appear promising tools for paleoceanographic reconstructions of sedimentary redox conditions.
Stefania Milano, Gernot Nehrke, Alan D. Wanamaker Jr., Irene Ballesta-Artero, Thomas Brey, and Bernd R. Schöne
Biogeosciences, 14, 1577–1591, https://doi.org/10.5194/bg-14-1577-2017, https://doi.org/10.5194/bg-14-1577-2017, 2017
Diana Zúñiga, Celia Santos, María Froján, Emilia Salgueiro, Marta M. Rufino, Francisco De la Granda, Francisco G. Figueiras, Carmen G. Castro, and Fátima Abrantes
Biogeosciences, 14, 1165–1179, https://doi.org/10.5194/bg-14-1165-2017, https://doi.org/10.5194/bg-14-1165-2017, 2017
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Diatoms are one of the most important primary producers in highly productive coastal regions. Their silicified valves are susceptible to escape from the upper water column and be preserved in the sediment record, and thus are frequently used to reconstruct environmental conditions in the past from sediment cores. Here, we assess how water column diatom’s community in the NW Iberian coastal upwelling system is seasonally transferred from the surface to the seafloor sediments.
Cited articles
Abbott, M. R., Richman, J. G., Nahorniak, J. S., and Barksdale, B. S.:
Meanders in the Antarctic Polar Frontal Zone and their impact on
phytoplankton, Deep-Sea Res. Pt. II, 48, 3891–3912,
https://doi.org/10.1016/S0967-0645(01)00073-X, 2001.
Alonso-Sáez, L., Andersson, A., Heinrich, F., and Bertilsson, S.: High
archaeal diversity in Antarctic circumpolar deep waters, Env. Microbiol.
Rep., 3, 689–697, https://doi.org/10.1111/j.1758-2229.2011.00282.x, 2011.
Bauerfeind, E., Nöthig, E. M., Beszczynska, A., Fahl, K., Kaleschke, L.,
Kreker, K., Klages, M., Soltwedel, T., Lorenzen, C., and Wegner, J.: Particle
sedimentation patterns in the eastern Fram Strait during 2000–2005: Results
from the Arctic long-term observatory HAUSGARTEN, Deep-Sea Res. Pt. I, 56, 1471–1487, https://doi.org/10.1016/j.dsr.2009.04.011, 2009.
Bauerfeind, E., Kattner, G., Ludwichowski, K.-U., Nöthig, E.-M., and
Sandhop, N.: Inorganic nutrients measured on water bottle samples at AWI
HAUSGARTEN during POLARSTERN cruise MSM29, PANGAEA, https://doi.org/10.1594/PANGAEA.834685,
2014.
Beman, J. M., Popp, B. N., and Francis, C. A.: Molecular and biogeochemical
evidence for ammonia oxidation by marine Crenarchaeota in the Gulf of
California, ISME J., 2, 429–441, https://doi.org/10.1038/ismej.2008.33, 2008.
Bendle, J. and Rosell-Melé, A.: Distributions of
Beszczynska-Möller, A., Fahrbach, E., Rohardt, G., and Schauer, U.:
Physical oceanography and current meter data from mooring F7-8, PANGAEA,
https://doi.org/10.1594/PANGAEA.800396, 2012a.
Beszczynska-Möller, A., Fahrbach, E., Schauer, U., and Hansen, E.:
Variability in Atlantic water temperature and transport at the entrance to
the Arctic Ocean, 1997–2010, ICES J. Mar. Sci., 69, 852–863,
https://doi.org/10.1093/icesjms/fss056, 2012b.
Blaga, C. I., Reichart, G. J., Heiri, O., and Sinninghe Damsté, J. S.:
Tetraether membrane lipid distributions in water-column particulate matter
and sediments: A study of 47 European lakes along a north-south transect, J.
Paleolimnol., 41, 523–540, https://doi.org/10.1007/s10933-008-9242-2, 2009.
Chen, W., Mohtadi, M., Schefuß, E., and Mollenhauer, G.:
Organic-geochemical proxies of sea surface temperature in surface sediments
of the tropical eastern Indian Ocean, Deep-Sea Res. Pt. I,
88, 17–29, https://doi.org/10.1016/j.dsr.2014.03.005, 2014.
Chen, W., Mohtadi, M., Schefuß, E., and Mollenhauer, G.: Concentrations
and abundance ratios of long-chain alkenones and glycerol dialkyl glycerol
tetraethers in sinking particles south of Java, Deep-Sea Res. Pt. I, 112, 14–24, https://doi.org/10.1016/j.dsr.2016.02.010, 2016.
Church, M. J., DeLong, E. F., Ducklow, H. W., Karner, M. B., Preston, C. M.,
and Karl, D. M.: Abundance and distribution of planktonic Archaea and
Bacteria in the waters west of the Antarctic Peninsula, Limnol. Oceanogr.,
48, 1893–1902, https://doi.org/10.4319/lo.2003.48.5.1893, 2003.
Conley, K. R. and Sutherland, K. R.: Particle shape impacts export and fate
in the ocean through interactions with the globally abundant appendicularian
Oikopleura dioica, PLoS One, 12, 1–17, https://doi.org/10.1371/journal.pone.0183105,
2017.
Fahrbach, E. and Cruise Participants: Report and preliminary results of the
Expeditions ANTARKTIS IX/2 of the Research Vessel Polarstern in 1990/91,
Punta Arenas-Cape Town, 16 November–30 December 1990, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany, 1992.
Fietz, S., Huguet, C., Rueda, G., Hambach, B., and Rosell-Melé, A.:
Hydroxylated isoprenoidal GDGTs in the Nordic Seas, Mar. Chem., 152, 1–10,
https://doi.org/10.1016/j.marchem.2013.02.007, 2013.
Fischer, G. and Karakaş, G.: Sinking rates and ballast composition of particles in the Atlantic Ocean: implications for the organic carbon fluxes to the deep ocean, Biogeosciences, 6, 85–102, https://doi.org/10.5194/bg-6-85-2009, 2009.
Fischer, G., Gersonde, R., and Wefer, G.: Organic carbon, biogenic silica and
diatom fluxes in the marginal winter sea-ice zone and in the Polar Front
Region: Interannual variations and differences in composition, Deep-Sea Res.
Pt. II, 49, 1721–1745,
https://doi.org/10.1016/S0967-0645(02)00009-7, 2002.
Freeman, N. M. and Lovenduski, N. S.: Mapping the Antarctic Polar Front: weekly realizations from 2002 to 2014, Earth Syst. Sci. Data, 8, 191–198, https://doi.org/10.5194/essd-8-191-2016, 2016.
Garcia, H. E., Locarnini, R. A., Boyer, T. P., Antonov, J. I., Baranova, O.
K., Zweng, M. M., Reagan, J. R., and Johnson, D. R.: World Ocean Atlas 2013,
Volume 4?: Dissolved Inorganic Nutrients (phosphate, nitrate, silicate),
NOAA Atlas NESDIS, 76, 25, https://doi.org/10.1182/blood-2011-06-357442, 2013.
Gersonde, R. and Participants, C.: Report and preliminary results of the
Expeditions ANTARKTIS VIII/3 of the Research Vessel Polarstern in 1989/90,
Cape Town-Punta Arenas, 1 November–1 December 1989, available at:
http://epic.awi.de/29793/1/PE_17.pdf (last access: 7 August 2018), 1990.
Hebbeln, D.: Flux of ice-rafted detritus from sea ice in the Fram Strait,
Deep-Sea Res. Pt. II, 47, 1773–1790,
https://doi.org/10.1016/S0967-0645(00)00006-0, 2000.
Hebbeln, D. and Wefer, G.: Effects of ice coverage and ice-rafted material
on sedimentation in the Fram Strait, Nature, 350, 409–411,
https://doi.org/10.1038/350409a0, 1991.
Herfort, L., Schouten, S., Abbas, B., Veldhuis, M. J. W., Coolen, M. J. L.,
Wuchter, C., Boon, J. P., Herndl, G. J., and Sinninghe Damsté, J. S.:
Variations in spatial and temporal distribution of Archaea in the North Sea
in relation to environmental variables, FEMS Microbiol. Ecol., 62,
242–257, https://doi.org/10.1111/j.1574-6941.2007.00397.x, 2007.
Ho, S. L., Mollenhauer, G., Fietz, S., Martínez-Garcia, A., Lamy, F.,
Rueda, G., Schipper, K., Méheust, M., Rosell-Melé, A., Stein, R., and
Tiedemann, R.: Appraisal of TEX86 and
Hopmans, E. C., Schouten, S., Pancost, R. D., Van Der Meer, M. T. J., and
Sinninghe Damsté, J. S.: Analysis of intact tetraether lipids in
archaeal cell material and sediments by high performance liquid
chromatography/atmospheric pressure chemical ionization mass spectrometry,
Rapid Commun. Mass Sp., 14, 585–589,
https://doi.org/10.1002/(SICI)1097-0231(20000415)14:7<585::AID-RCM913>3.0.CO;2-N, 2000.
Hopmans, E. C., Weijers, J. W. H., Schefuß, E., Herfort, L., Sinninghe
Damsté, J. S., and Schouten, S.: A novel proxy for terrestrial organic
matter in sediments based on branched and isoprenoid tetraether lipids,
Earth Planet. Sc. Lett., 224, 107–116, https://doi.org/10.1016/j.epsl.2004.05.012,
2004.
Horak, R. E. A., Qin, W., Bertagnolli, A. D., Nelson, A., Heal, K. R., Han,
H., Heller, M., Schauer, A. J., Jeffrey, W. H., Armbrust, E. V., Moffett, J.
W., Ingalls, A. E., Stahl, D. A., and Devol, A. H.: Relative impacts of
light, temperature, and reactive oxygen on thaumarchaeal ammonia oxidation
in the North Pacific Ocean, Limnol. Oceanogr., 63, 1–16,
https://doi.org/10.1002/lno.10665, 2017.
Huguet, C., Cartes, J. E., Sinninghe Damsté, J. S., and Schouten, S.:
Marine crenarchaeotal membrane lipids in decapods: Implications for the
TEX86 paleothermometer, Geochem. Geophy.
Geosy., 7, Q11010, https://doi.org/10.1029/2006GC001305, 2006.
Huguet, C., Schimmelmann, A., Thunell, R., Lourens, L. J., Sinninghe
Damsté, J. S., and Schouten, S.: A study of the
TEX86 paleothermometer in the water column and
sediments of the Santa Barbara Basin, California, Paleoceanography, 22,
PA3203, https://doi.org/10.1029/2006PA001310, 2007.
Huguet, C., Fietz, S., and Rosell-Melé, A.: Global distribution patterns
of hydroxy glycerol dialkyl glycerol tetraethers, Org. Geochem., 57,
107–118, https://doi.org/10.1016/j.orggeochem.2013.01.010, 2013.
Hurley, S. J., Elling, F. J., Könneke, M., Buchwald, C., Wankel, S. D.,
Santoro, A. E., Lipp, J. S., Hinrichs, K.-U., and Pearson, A.: Influence of
ammonia oxidation rate on thaumarchaeal lipid composition and the
TEX86 temperature proxy, P. Natl. Acad. Sci.
USA, 113, 7762–7767, https://doi.org/10.1073/pnas.1518534113, 2016.
Inglis, G. N., Farnsworth, A., Lunt, D., Foster, G. L., Hollis, C. J.,
Pagani, M., Jardine, P. E., Pearson, P. N., Markwick, P., and Galsworthy, A.
M. J.: Descent toward the Icehouse: Eocene sea surface cooling inferred from
GDGT distributions, Paleoceanography, 30, 1000–1020,
https://doi.org/10.1002/2014PA002723, 2015.
Iversen, M. H. and Ploug, H.: Ballast minerals and the sinking carbon flux in the ocean: carbon-specific respiration rates and sinking velocity of marine snow aggregates, Biogeosciences, 7, 2613–2624, https://doi.org/10.5194/bg-7-2613-2010, 2010.
Iversen, M. H., Nowald, N., Ploug, H., Jackson, G. A., and Fischer, G.: High
resolution profiles of vertical particulate organic matter export off Cape
Blanc, Mauritania: Degradation processes and ballasting effects, Deep-Sea Res.
Pt. I, 57, 771–784, https://doi.org/10.1016/j.dsr.2010.03.007,
2010.
Iversen, M. H., Pakhomov, E. A., Hunt, B. P. V., van der Jagt, H.,
Wolf-Gladrow, D., and Klaas, C.: Sinkers or floaters? Contribution from salp
pellets to the export flux during a large bloom event in the Southern Ocean,
Deep-Sea Res. Pt. II, 138, 116–125,
https://doi.org/10.1016/j.dsr2.2016.12.004, 2017.
Jackson, G. A. and Checkley Jr., D. M.: Particle size distribution in the
upper 100 m water column and their implications for animal feeding in the
plankton, Deep-Sea Res. Pt. I, 58, 283–297,
https://doi.org/10.1016/j.dsr.2010.12.008, 2011.
Kattner, G. and Participants, C.: Reports on Polar and Marine Research. The
Expedition of the Research Vessel Polarstern to the Arctic in 2008
(ARK-XXIII/2), Longyearbyen-Reykjavik, 6 July–10 August 2008, available
at: http://epic.awi.de/28933/1/Kat2009b.pdf (last access: 7 August 2018), 2009.
Kim, J. H., Schouten, S., Hopmans, E. C., Donner, B. and Sinninghe Damsté, J. S.: Global sediment core-top calibration of the TEX86 paleothermometer in the ocean, Geochim. Cosmochim. Acta, 72, 1154–1173, https://doi.org/10.1016/j.gca.2007.12.010, 2008.
Kim, J. H., Crosta, X., Michel, E., Schouten, S., Duprat, J., and Sinninghe
Damsté, J. S.: Impact of lateral transport on organic proxies in the
Southern Ocean, Quaternary Res., 71, 246–250,
https://doi.org/10.1016/j.yqres.2008.10.005, 2009.
Kim, J.-H., van der Meer, J., Schouten, S., Helmke, P., Willmott, V.,
Sangiorgi, F., Koç, N., Hopmans, E. C., and Sinninghe Damsté, J. S.:
New indices and calibrations derived from the distribution of crenarchaeal
isoprenoid tetraether lipids: Implications for past sea surface temperature
reconstructions, Geochim. Cosmochim. Ac., 74, 4639–4654,
https://doi.org/10.1016/j.gca.2010.05.027, 2010.
Kim, J.-H., Schouten, S., Rodrigo-Gámiz, M., Rampen, S., Marino, G.,
Huguet, C., Helmke, P., Buscail, R., Hopmans, E. C., Pross, J., Sangiorgi,
F., Middelburg, J. B. M., and Sinninghe Damsté, J. S.: Influence of
deep-water derived isoprenoid tetraether lipids on the
Klages, M. and Participants, C.: Reports on Polar and Marine Research, The
Expedition of the Research Vessel Polarstern to the Arctic in 2007
(ARK-XXII/1a-c, Bremerhaven-Tromso-Longyarbyen-Tromso, 29 May–25 July 2007,
Alfred-Wegener Institute, available at:
http://epic.awi.de/29744/1/Kla2011a.pdf (last access: 7 August 2018), 2007.
Könneke, M., Bernhard, A. E., de la Torre, J. R., Walker, C. B.,
Waterbury, J. B., and Stahl, D. A.: Isolation of an autotrophic
ammonia-oxidizing marine archaeon, Nature, 437, 543–546,
https://doi.org/10.1038/nature03911, 2005.
Lalande, C., Bauerfeind, E., Nöthig, E. M., and Beszczynska-Möller,
A.: Impact of a warm anomaly on export fluxes of biogenic matter in the
eastern Fram Strait, Prog. Oceanogr., 109, 70–77,
https://doi.org/10.1016/j.pocean.2012.09.006, 2013.
Lalande, C., Nöthig, E. M., Bauerfeind, E., Hardge, K.,
Beszczynska-Möller, A., and Fahl, K.: Lateral supply and downward export
of particulate matter from upper waters to the seafloor in the deep eastern
Fram Strait, Deep-Sea Res. Pt. I, 114, 78–89,
https://doi.org/10.1016/j.dsr.2016.04.014, 2016.
Laubscher, R. K., Prissinotto, R., and McQuaid, C. D.: Phytoplankton
production and biomass at frontal zones in the Atlantic sector of the
Southern Ocean, Polar Biol., 13, 471–481, 1993.
Lee, K. E., Kim, J.-H., Wilke, I., Helmke, P., and Schouten, S.: A study of
the alkenone, TEX86, and planktonic foraminifera in
the Benguela Upwelling System: Implications for past sea surface temperature
estimates, Geochem. Geophy. Geosy., 9, 1–19,
https://doi.org/10.1029/2008GC002056, 2008.
Lincoln, S. A., Wai, B., Eppley, J. M., Church, M. J., Summons, R. E., and
DeLong, E. F.: Planktonic Euryarchaeota are a significant source of archaeal
tetraether lipids in the ocean, P. Natl. Acad. Sci. USA, 111,
9858–9863, https://doi.org/10.1073/pnas.1409439111, 2014.
Liu, X. L., Lipp, J. S., Simpson, J. H., Lin, Y. S., Summons, R. E., and
Hinrichs, K. U.: Mono- and dihydroxyl glycerol dibiphytanyl glycerol
tetraethers in marine sediments: Identification of both core and intact
polar lipid forms, Geochim. Cosmochim. Ac., 89, 102–115,
https://doi.org/10.1016/j.gca.2012.04.053, 2012.
Locarnini, R. A., Mishonov, A. V., Antonov, J. I., Boyer, T. P., Garcia, H.
E., Baranova, O. K., Zweng, M. M., Paver, C. R., Reagan, J. R., Johnson, D.
R., Hamilton, M., and Seidov, D.: World Ocean Atlas 2013, Volume 1:
Temperature, edited by: Levitus, S. and Mishonov, A., NOAA Atlas NESDIS, 73,
40, https://doi.org/10.1182/blood-2011-06-357442, 2013.
López-García, P., Rodriguez-Valera, F., Pedrós-Alió, C., and
Moreira, D.: Unexpected diversity of small eukaryotes in deep-sea Antarctic
plankton, Nature, 409, 603–607, https://doi.org/10.1038/35054537, 2001.
Lü, X., Liu, X. L., Elling, F. J., Yang, H., Xie, S., Song, J., Li, X.,
Yuan, H., Li, N., and Hinrichs, K. U.: Hydroxylated isoprenoid GDGTs in
Chinese coastal seas and their potential as a paleotemperature proxy for
mid-to-low latitude marginal seas, Org. Geochem., 89–90, 31–43,
https://doi.org/10.1016/j.orggeochem.2015.10.004, 2015.
Manley, T. O.: Branching of Atlantic Water within the Greenland-Spitsbergen
Passage: An estimate of recirculation, J. Geophys. Res., 100, 20627–20634,
https://doi.org/10.1029/95JC01251, 1995.
Martin-Cuadrado, A.-B., Rodriguez-Valera, F., Moreira, D., Alba, J. C.,
Ivars-Martínez, E., Henn, M. R., Talla, E., and López-García,
P.: Hindsight in the relative abundance, metabolic potential and genome
dynamics of uncultivated marine archaea from comparative metagenomic
analyses of bathypelagic plankton of different oceanic regions, ISME J., 2,
865–886, https://doi.org/10.1038/ismej.2008.40, 2008.
Meyer, V. D., Max, L., Hefter, J., Tiedemann, R., and Mollenhauer, G.:
Glacial-to-Holocene evolution of sea surface temperature and surface
circulation in the subarctic northwest Pacific and the Western Bering Sea,
Paleoceanography, 31, 916–927, https://doi.org/10.1002/2015PA002877, 2016.
Mollenhauer, G., Eglinton, T. I., Hopmans, E. C., and Sinninghe Damsté,
J. S.: A radiocarbon-based assessment of the preservation characteristics of
crenarchaeol and alkenones from continental margin sediments, Org. Geochem.,
39, 1039–1045, https://doi.org/10.1016/j.orggeochem.2008.02.006, 2008.
Mollenhauer, G., Basse, A., Kim, J.-H., Sinninghe Damsté, J. S., and
Fischer, G.: A four-year record of
Moore, J. K. and Abbott, M. R.: Phytoplankton chlorophyll distributions and
primary production in the Southern Ocean, J. Geophys. Res.-Ocean., 105,
28709–28722, https://doi.org/10.1029/1999JC000043, 2000.
Moore, J. K. and Abbott, M. R.: Surface chlorophyll concentrations in
relation to the Antarctic Polar Front: seasonal and spatial patterns from
satellite observations, J. Marine Syst., 37, 69–86,
https://doi.org/10.1016/S0924-7963(02)00196-3, 2002.
Moore, J. K., Abbott, M. R., and Richman, J. G.: Location and dynamics of the
Antarctic Polar Front from satellite sea surface temperature data, J.
Geophys. Res., 102, 3059–3074, https://doi.org/10.1029/97JC01705, 1999.
Moreau, R. A., Whitaker, B. D., and Hicks, K. B.: Phytosterols, phytostanols,
and their conjugates in foods: structural diversity, quantitative analysis,
and health-promoting uses, Prog. Lipid Res., 41, 457–500,
https://doi.org/10.1016/S0163-7827(02)00006-1, 2002.
Moreira, D., Rodríguez-Valera, F., and López-García, P.:
Analysis of a genome fragment of a deep-sea uncultivated Group II
euryarchaeote containing 16S rDNA, a spectinomycin-like operon and several
energy metabolism genes, Environ. Microbiol., 6, 959–969,
https://doi.org/10.1111/j.1462-2920.2004.00644.x, 2004.
Müller, P. J. and Fischer, G.: C37-Alkenones as Paleotemperature
Tool: Fundamentals Based on Sediment Traps and Surface Sediments from the
South Atlantic Ocean, in: The South Atlantic in the Late Quaternary, edited
by: Wefer, G., Mulitza, S., and Ratmeyer, V., 167–193, Springer, Berlin,
Heidelberg, 2003.
Murray, A. E., Wul, K. Y., Moyer, C. L., Karl, D. M., and Delong, E. F.:
Evidence for Circumpolar Distribution of Planktonic Archaea in the Southern
Ocean, Aquat. Microbiol. Ecol., 18, 263–273, 1999.
Nöthig, E.-M., Bracher, A., Engel, A., Metfies, K., Niehoff, B., Peeken,
I., Bauerfeind, E., Cherkasheva, A., Gäbler-Schwarz, S., Hardge, K.,
Kilias, E., Kraft, A., Kidane, Y. M., Lalande, C., Piontek, J., Thomisch, K.,
and Wurst, M.: Summertime plankton ecology in Fram Strait-a compilation of
long-and short-term observations, Polar Res., 34, 1–18,
https://doi.org/10.3402/polar.v34.23349, 2015.
Orsi, A. H., Whitworth III, T., and Nowlin Jr., W. D.: On the meridional
extent and fronts of the Antarctic Circumpolar Current, Deep-Sea Res. Pt. I, 42, 641–673, https://doi.org/10.1016/0967-0637(95)00021-W, 1995.
Park, E., Hefter, J., Fischer, G., and Mollenhauer, G.:
TEX86 in sinking particles in three eastern
Atlantic upwelling regimes, Org. Geochem., 124, 151–163,
https://doi.org/10.1016/j.orggeochem.2018.07.015, 2018.
Park, E., Hefter, J., Fischer, G., Iversen, M. H., Ramondenc, S., Nöthig, E.-M., and Mollenhauer, G.: Fractional abundances and concentrations of GDGT collected by sediment trap moored in two latitude regions of the Atlantic Ocean: in the eastern Fram Strait (FEVI16) and in the Antarctic Polar Front (PF3), PANGAEA, https://doi.org/10.1594/PANGAEA.897268, 2019.
Pitcher, A., Wuchter, C., Siedenberg, K., Schouten, S., and Sinninghe
Damsté, J. S.: Crenarchaeol tracks winter blooms of ammonia-oxidizing
Thaumarchaeota in the coastal North Sea, Limnol. Oceanogr., 56, 2308–2318,
https://doi.org/10.4319/lo.2011.56.6.2308, 2011.
Ploug, H., Iversen, M. H., and Fischer, G.: Ballast, sinking velocity, and
apparent diffusivity within marine snow and zooplankton fecal pellets:
Implications for substrate turnover by attached bacteria, Limnol. Oceanogr.,
53, 1878–1886, https://doi.org/10.4319/lo.2008.53.5.1878, 2008a.
Ploug, H., Iversen, M. H., Koski, M., and Buitenhuis, E. T.: Production,
oxygen respiration rates, and sinking velocity of copepod fecal pellets:
Direct measurements of ballasting by opal and calcite, Limnol. Oceanogr.,
53, 469–476, https://doi.org/10.4319/lo.2008.53.2.0469, 2008b.
Read, J. F., Pollard, R. T., and Bathmann, U.: Physical and biological
patchiness of an upper ocean transect from South Africa to the ice edge near
the Greenwich Meridian, Deep-Sea Res. Pt. II, 49,
3713–3733, https://doi.org/10.1016/S0967-0645(02)00108-X, 2002.
Reynolds, R. W., Smith, T. M., Liu, C., Chelton, D. B., Casey, K. S., and
Schlax, M. G.: Daily high-resolution-blended analyses for sea surface
temperature, J. Climate, 20, 5473–5496, https://doi.org/10.1175/2007JCLI1824.1, 2007.
Richey, J. N. and Tierney, J. E.: GDGT and alkenone flux in the northern
Gulf of Mexico: Implications for the TEX86 and
Rodrigo-Gámiz, M., Rampen, S. W., de Haas, H., Baas, M., Schouten, S., and Sinninghe Damsté, J. S.: Constraints on the applicability of the organic temperature proxies
Schlitzer, R.: Ocean Data View, available at:
http://odv.awi.de (last access: 3 May 2018), 2017.
Schouten, S., Hopmans, E. C., Schefuß, E., and Damsté, J. S. S.:
Distributional variations in marine crenarchaeotal membrane lipids: a new
tool for reconstructing ancient sea water temperatures?, Earth Planet. Sc.
Lett., 204, 265–274, https://doi.org/10.1016/S0012-821X(02)00979-2, 2002.
Schouten, S., van der Meer, M. T. J., Hopmans, E. C., and Sinninghe
Damsté, J. S.: Comment on “Lipids of marine Archaea: Patterns and
provenance in the water column and sediments” by Turich et al. (2007),
Geochim. Cosmochim. Ac., 72, 5342–5346, https://doi.org/10.1016/j.gca.2008.03.028,
2008.
Schouten, S., Villanueva, L., Hopmans, E. C., van der Meer, M. T. J., and
Sinninghe Damsté, J. S.: Are Marine Group II Euryarchaeota significant
contributors to tetraether lipids in the ocean?, P. Natl. Acad. Sci. USA, 111, E4285, https://doi.org/10.1073/pnas.1416176111, 2014.
Seki, O., Bendle, J. A., Harada, N., Kobayashi, M., Sawada, K., Moossen, H.,
Inglis, G. N., Nagao, S., and Sakamoto, T.: Assessment and calibration of
TEX86 paleothermometry in the Sea of Okhotsk and
sub-polar North Pacific region: Implications for paleoceanography, Prog.
Oceanogr., 126, 254–266, https://doi.org/10.1016/j.pocean.2014.04.013, 2014.
Shevenell, A. E., Ingalls, A. E., Domack, E. W., and Kelly, C.: Holocene
Southern Ocean surface temperature variability west of the Antarctic
Peninsula, Nature, 470, 250–254, https://doi.org/10.1038/nature09751, 2011.
Sluijs, A., Schouten, S., Pagani, M., Woltering, M., Brinkhuis, H.,
Damsté, J. S. S., Dickens, G. R., Huber, M., Reichart, G.-J., Stein, R.,
Matthiessen, J., Lourens, L. J., Pedentchouk, N., Backman, J., Moran, K., and
the Expedition 302 Scientists: Subtropical Arctic Ocean temperatures during
the Palaeocene/Eocene thermal maximum, Nature, 441, 610–613,
https://doi.org/10.1038/nature04668, 2006.
Soltwedel, T., Bauerfeind, E., Bergmann, M., Bracher, A., Budaeva, N.,
Busch, K., Cherkasheva, A., Fahl, K., Grzelak, K., Hasemann, C., Jacob, M.,
Kraft, A., Lalande, C., Metfies, K., Nöthig, E. M., Meyer, K.,
Quéric, N. V., Schewe, I., Włodarska-Kowalczuk, M., and Klages, M.:
Natural variability or anthropogenically-induced variation? Insights from 15
years of multidisciplinary observations at the arctic marine LTER site
HAUSGARTEN, Ecol. Indic., 65, 89–102, https://doi.org/10.1016/j.ecolind.2015.10.001,
2016.
Taylor, K. W. R., Huber, M., Hollis, C. J., Hernandez-Sanchez, M. T., and
Pancost, R. D.: Re-evaluating modern and Palaeogene GDGT distributions:
Implications for SST reconstructions, Global Planet. Change, 108, 158–174,
https://doi.org/10.1016/j.gloplacha.2013.06.011, 2013.
Tierney, J. E. and Tingley, M. P.: A TEX86 surface
sediment database and extended Bayesian calibration, Sci. Data, 2, 150029,
https://doi.org/10.1038/sdata.2015.29, 2015.
Tolar, B. B., Ross, M. J., Wallsgrove, N. J., Liu, Q., Aluwihare, L. I.,
Popp, B. N., and Hollibaugh, J. T.: Contribution of ammonia oxidation to
chemoautotrophy in Antarctic coastal waters, ISME J., 10, 2605–2619,
https://doi.org/10.1038/ismej.2016.61, 2016.
Turich, C., Freeman, K. H., Bruns, M. A., Conte, M., Jones, A. D., and
Wakeham, S. G.: Lipids of marine Archaea: Patterns and provenance in the
water-column and sediments, Geochim. Cosmochim. Ac., 71, 3272–3291,
https://doi.org/10.1016/j.gca.2007.04.013, 2007.
Walczowski, W.: Frontal structures in the West Spitsbergen Current margins, Ocean Sci., 9, 957–975, https://doi.org/10.5194/os-9-957-2013, 2013.
Walter, H. J., Geibert, W., Rutgers Van Der Loeff, M. M., Fischer, G., and
Bathmann, U.: Shallow vs. deep-water scavenging of 231Pa and 230Th
in radionuclide enriched waters of the Atlantic sector of the Southern
Ocean, Deep-Sea Res. Pt. I, 48, 471–493,
https://doi.org/10.1016/S0967-0637(00)00046-7, 2001.
Wassmann, P., Reigstad, M., Haug, T., Rudels, B., Carroll, M. L., Hop, H.,
Gabrielsen, G. W., Falk-Petersen, S., Denisenko, S. G., Arashkevich, E.,
Slagstad, D., and Pavlova, O.: Food webs and carbon flux in the Barents Sea,
Prog. Oceanogr., 71, 232–287, https://doi.org/10.1016/j.pocean.2006.10.003, 2006.
Weijers, J. W. H., Schouten, S., Spaargaren, O. C., and Sinninghe Damsté,
J. S.: Occurrence and distribution of tetraether membrane lipids in soils:
Implications for the use of the TEX86 proxy and the
BIT index, Org. Geochem., 37, 1680–1693,
https://doi.org/10.1016/j.orggeochem.2006.07.018, 2006.
Weijers, J. W. H., Lim, K. L. H., Aquilina, A., Damsté, J. S. S., and
Pancost, R. D.: Biogeochemical controls on glycerol dialkyl glycerol
tetraether lipid distributions in sediments characterized by diffusive
methane flux, Geochem. Geophys. Geosy., 12, 1–15,
https://doi.org/10.1029/2011GC003724, 2011.
Wekerle, C., Krumpen, T., Dinter, T., von Appen, W.-J., Iversen, M. H., and
Salter, I.: Properties of Sediment Trap Catchment Areas in Fram Strait:
Results From Lagrangian Modeling and Remote Sensing, Front. Mar. Sci.,
5, 1–16, https://doi.org/10.3389/fmars.2018.00407, 2018.
Wuchter, C., Abbas, B., Coolen, M. J. L., Herfort, L., van Bleijswijk, J.,
Timmers, P., Strous, M., Teira, E., Herndl, G. J., Middelburg, J. J.,
Schouten, S., and Sinninghe Damsté, J. S.: Archaeal nitrification in the
ocean, P. Natl. Acad. Sci. USA, 103, 12317–12322,
https://doi.org/10.1073/pnas.0701630104, 2006a.
Wuchter, C., Schouten, S., Wakeham, S. G., and Sinninghe Damsté, J. S.:
Archaeal tetraether membrane lipid fluxes in the northeastern Pacific and
the Arabian Sea: Implications for TEX86
paleothermometry, Paleoceanography, 21, 1–9, https://doi.org/10.1029/2006PA001279,
2006b.
Yamamoto, M., Shimamoto, A., Fukuhara, T., Tanaka, Y., and Ishizaka, J.:
Glycerol dialkyl glycerol tetraethers and TEX86
index in sinking particles in the western North Pacific, Org. Geochem., 53,
52–62, https://doi.org/10.1016/j.orggeochem.2012.04.010, 2012.
Zhang, Y. G., Zhang, C. L., Liu, X.-L., Li, L., Hinrichs, K.-U., and Noakes,
J. E.: Methane Index: A tetraether archaeal lipid biomarker indicator for
detecting the instability of marine gas hydrates, Earth Planet. Sc. Lett.,
307, 525–534, https://doi.org/10.1016/j.epsl.2011.05.031, 2011.
Zhang, Y. G., Pagani, M., and Wang, Z.: Ring Index: A new strategy to
evaluate the integrity of TEX86 paleothermometry,
Paleoceanography, 31, 220–232, https://doi.org/10.1002/2015PA002848, 2016.
Short summary
We analyzed GDGT-based proxy temperatures in the polar oceans. In the eastern Fram Strait (79° N), the nutrient distribution may determine the depth habit of Thaumarchaeota and thus the proxy temperature. In the Antarctic Polar Front (50° S), the contribution of Euryarchaeota or the nonlinear correlation between the proxy values and temperatures may cause the warm biases of the proxy temperatures relative to SSTs.
We analyzed GDGT-based proxy temperatures in the polar oceans. In the eastern Fram Strait...
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