Articles | Volume 17, issue 2
https://doi.org/10.5194/cp-17-603-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-17-603-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
09 Mar 2021
Research article |
| 09 Mar 2021
| 09 Mar 2021
Nutrient utilization and diatom productivity changes in the low-latitude south-eastern Atlantic over the past 70 ka: response to Southern Ocean leakage
Katharine Hendry
CORRESPONDING AUTHOR
University of Bristol, School of Earth Sciences, Bristol BS8 1RJ, UK
Oscar Romero
MARUM – Center for Marine Environmental Sciences, University of Bremen, 28359 Bremen, Germany
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, 27568 Bremerhaven, Germany
Vanessa Pashley
Geochronology and Tracers Facility, British Geological Survey, Keyworth NG12 5GG, UK
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Alan Marron, Lucie Cassarino, Jade Hatton, Paul Curnow, and Katharine R. Hendry
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Gerard J. M. Versteegh, Karin A. F. Zonneveld, Jens Hefter, Oscar E. Romero, Gerhard Fischer, and Gesine Mollenhauer
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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
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Monitoring of the multiannual evolution of populations representing different trophic levels allows for obtaining insights into the impact of climate variability in marine coastal upwelling ecosystems. By using a multiyear, continuous (1,900 d) sediment trap record, we assess the dynamics and fluxes of calcareous, organic and siliceous microorganisms off Mauritania (NW Africa). The experiment allowed for the recognition of a general sequence of seasonal variations of the main populations.
Alan Marron, Lucie Cassarino, Jade Hatton, Paul Curnow, and Katharine R. Hendry
Biogeosciences, 16, 4805–4813, https://doi.org/10.5194/bg-16-4805-2019, https://doi.org/10.5194/bg-16-4805-2019, 2019
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Lucie Cassarino, Christopher D. Coath, Joana R. Xavier, and Katharine R. Hendry
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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.
V. N. Panizzo, G. E. A. Swann, A. W. Mackay, E. Vologina, M. Sturm, V. Pashley, and M. S. A. Horstwood
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Lake Baikal, Siberia, is the world's most voluminous lake. Diatoms are the most dominant primary producers in the lake and form the basis of the food chain. This paper investigated the productivity of these organisms over the course of a year with a view to understanding their preservation in sediments and their value for reconstructing past productivity in the lake. This is important when recent climate change and the pressures of pollution are having demonstrable impacts in the region.
C. L. McKay, J. Groeneveld, H. L. Filipsson, D. Gallego-Torres, M. J. Whitehouse, T. Toyofuku, and O.E. Romero
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O. Cartapanis, K. Tachikawa, O. E. Romero, and E. Bard
Clim. Past, 10, 405–418, https://doi.org/10.5194/cp-10-405-2014, https://doi.org/10.5194/cp-10-405-2014, 2014
Related subject area
Subject: Carbon Cycle | Archive: Marine Archives | Timescale: Pleistocene
Environmental controls of rapid terrestrial organic matter mobilization to the western Laptev Sea since the Last Deglaciation
Persistent deep-water formation in the Nordic Seas during Marine Isotope Stages 5 and 4 notwithstanding changes in Atlantic overturning
No detectable influence of the carbonate ion effect on changes in stable carbon isotope ratios (δ13C) of shallow dwelling planktic foraminifera over the past 160 kyr
Deglacial export of pre-aged terrigenous carbon to the Bay of Biscay
Atmospheric CO2 estimates for the Miocene to Pleistocene based on foraminiferal δ11B at Ocean Drilling Program Sites 806 and 807 in the Western Equatorial Pacific
Coccolithophore productivity at the western Iberian Margin during the Middle Pleistocene (310–455 ka) – evidence from coccolith Sr∕Ca data
Carbon burial in deep-sea sediment and implications for oceanic inventories of carbon and alkalinity over the last glacial cycle
Tsai-Wen Lin, Tommaso Tesi, Jens Hefter, Hendrik Grotheer, Jutta Wollenburg, Florian Adolphi, Henning A. Bauch, Alessio Nogarotto, Juliane Müller, and Gesine Mollenhauer
Clim. Past, 21, 753–772, https://doi.org/10.5194/cp-21-753-2025, https://doi.org/10.5194/cp-21-753-2025, 2025
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In order to understand the mechanisms governing permafrost organic matter remobilization, we investigated organic matter composition during past intervals of rapid sea-level rise, of inland warming, and of dense sea-ice cover in the Laptev Sea. We find that sea-level rise resulted in widespread erosion and transport of permafrost materials to the ocean but that erosion is mitigated by regional dense sea-ice cover. Factors like inland warming or floods increase permafrost mobilization locally.
Tim Beneke Stobbe, Henning Alexander Bauch, Daniel Alexander Frick, Jimin Yu, and Julia Gottschalk
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New bottom water [CO32-] reconstructions show higher levels in the deep Norwegian Sea during MIS 5 and 4 than during the Holocene. This suggests modern-like/persistent deep-water formation in this region, even when Atlantic overturning weakened and/or shoaled. Our data puts new constraints on the endmember [CO32-] composition of northern component-waters emerging from the Nordic Seas, with implications for the chemical characteristics and carbon storage capacity of the Atlantic Ocean.
Peter Köhler and Stefan Mulitza
Clim. Past, 20, 991–1015, https://doi.org/10.5194/cp-20-991-2024, https://doi.org/10.5194/cp-20-991-2024, 2024
Short summary
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We constructed 160 kyr long mono-specific stacks of δ13C and of δ18O from the wider tropics from the planktic foraminifera G. ruber and/or T. sacculifer and compared them with carbon cycle simulations using the BICYCLE-SE model. In our stacks and our model-based interpretation, we cannot detect a species-specific isotopic fractionation during hard-shell formation as a function of carbonate chemistry in the surrounding seawater, something which is called a carbonate ion effect.
Eduardo Queiroz Alves, Wanyee Wong, Jens Hefter, Hendrik Grotheer, Tommaso Tesi, Torben Gentz, Karin Zonneveld, and Gesine Mollenhauer
Clim. Past, 20, 121–136, https://doi.org/10.5194/cp-20-121-2024, https://doi.org/10.5194/cp-20-121-2024, 2024
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Our study reveals a previously unknown peat source for the massive influx of terrestrial organic matter that was exported from the European continent to the ocean during the last deglaciation. Our findings shed light on ancient terrestrial organic carbon mobilization, providing insights that are crucial for refining climate models.
Maxence Guillermic, Sambuddha Misra, Robert Eagle, and Aradhna Tripati
Clim. Past, 18, 183–207, https://doi.org/10.5194/cp-18-183-2022, https://doi.org/10.5194/cp-18-183-2022, 2022
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Here we reconstruct atmospheric CO2 values across major climate transitions over the past 16 million years (Myr) from two sites in the West Pacific Warm Pool using a pH proxy on surface-dwelling foraminifera. We are able to reproduce pCO2 data from ice cores; therefore we apply the same framework to older samples to create a long-term pH and pCO2 reconstruction. We give quantitative constraints on pH and pCO2 changes over the main climate transitions of the last 16 Myr.
Catarina Cavaleiro, Antje H. L. Voelker, Heather Stoll, Karl-Heinz Baumann, and Michal Kucera
Clim. Past, 16, 2017–2037, https://doi.org/10.5194/cp-16-2017-2020, https://doi.org/10.5194/cp-16-2017-2020, 2020
Olivier Cartapanis, Eric D. Galbraith, Daniele Bianchi, and Samuel L. Jaccard
Clim. Past, 14, 1819–1850, https://doi.org/10.5194/cp-14-1819-2018, https://doi.org/10.5194/cp-14-1819-2018, 2018
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A data-based reconstruction of carbon-bearing deep-sea sediment shows significant changes in the global burial rate over the last glacial cycle. We calculate the impact of these deep-sea changes, as well as hypothetical changes in continental shelf burial and volcanic outgassing. Our results imply that these geological fluxes had a significant impact on ocean chemistry and the global carbon isotopic ratio, and that the natural carbon cycle was not in steady state during the Holocene.
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Short summary
Productive eastern boundary upwelling systems (EBUs) are characterized by abundant siliceous algae and diatoms, and they play a key role in carbon fixation. Understanding past shifts in diatom production is critical for predicting the impact of future climate change. We combine existing sediment archives from the Benguela EBU with new diatom isotope analyses and modelling to reconstruct late Quaternary silica cycling, which we suggest depends on both upwelling intensity and surface utilization.
Productive eastern boundary upwelling systems (EBUs) are characterized by abundant siliceous...
