Articles | Volume 19, issue 10
https://doi.org/10.5194/bg-19-2599-2022
© Author(s) 2022. 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-19-2599-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
25 May 2022
Research article |
| 25 May 2022
| 25 May 2022
Summer trends and drivers of sea surface fCO2 and pH changes observed in the southern Indian Ocean over the last two decades (1998–2019)
Coraline Leseurre
CORRESPONDING AUTHOR
Laboratoire d'Océanographie et du Climat: Expérimentation et Approches Numériques (LOCEAN-IPSL), Sorbonne Université-CNRS-IRD-MNHN, Paris, 75005, France
Claire Lo Monaco
Laboratoire d'Océanographie et du Climat: Expérimentation et Approches Numériques (LOCEAN-IPSL), Sorbonne Université-CNRS-IRD-MNHN, Paris, 75005, France
Gilles Reverdin
Laboratoire d'Océanographie et du Climat: Expérimentation et Approches Numériques (LOCEAN-IPSL), Sorbonne Université-CNRS-IRD-MNHN, Paris, 75005, France
Nicolas Metzl
Laboratoire d'Océanographie et du Climat: Expérimentation et Approches Numériques (LOCEAN-IPSL), Sorbonne Université-CNRS-IRD-MNHN, Paris, 75005, France
Jonathan Fin
Laboratoire d'Océanographie et du Climat: Expérimentation et Approches Numériques (LOCEAN-IPSL), Sorbonne Université-CNRS-IRD-MNHN, Paris, 75005, France
Claude Mignon
Laboratoire d'Océanographie et du Climat: Expérimentation et Approches Numériques (LOCEAN-IPSL), Sorbonne Université-CNRS-IRD-MNHN, Paris, 75005, France
Léa Benito
Laboratoire d'Océanographie et du Climat: Expérimentation et Approches Numériques (LOCEAN-IPSL), Sorbonne Université-CNRS-IRD-MNHN, Paris, 75005, France
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In the southern Indian Ocean, south of the Polar Front, observed increase of sea surface fCO2 and decrease of pH over 1985–2021 are mainly driven by anthropogenic CO2 uptake but in the last decade (2010–2020) fCO2 and pH were stable in summer highlighting the competitive balance between anthropogenic CO2 and primary production. In the water column the increase of anthropogenic CO2 concentrations leads to a migration of the aragonite saturation state from 600 m in 1985 up to 400 m in 2021.
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During an oceanographic cruise conducted in January 2020 in the south-western Indian Ocean, we observed very low CO2 concentrations associated with a strong phytoplankton bloom that occurred south-east of Madagascar. This biological event led to a strong regional CO2 ocean sink not previously observed.
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Coraline Leseurre, Claire Lo Monaco, Gilles Reverdin, Nicolas Metzl, Jonathan Fin, Solveig Olafsdottir, and Virginie Racapé
Biogeosciences, 17, 2553–2577, https://doi.org/10.5194/bg-17-2553-2020, https://doi.org/10.5194/bg-17-2553-2020, 2020
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In this study, we investigate the evolution of CO2 uptake and ocean acidification in the North Atlantic Subpolar surface water. Our results show an important reduction in the capacity of the ocean to absorb CO2 from the atmosphere (1993–2007), due to a rapid increase in the fCO2 and associated with a rapid decrease in pH. Conversely, data obtained during the last decade (2008–2017) show a stagnation of fCO2 (increasing the ocean sink for CO2) and pH.
Manon Tonnard, Hélène Planquette, Andrew R. Bowie, Pier van der Merwe, Morgane Gallinari, Floriane Desprez de Gésincourt, Yoan Germain, Arthur Gourain, Marion Benetti, Gilles Reverdin, Paul Tréguer, Julia Boutorh, Marie Cheize, François Lacan, Jan-Lukas Menzel Barraqueta, Leonardo Pereira-Contreira, Rachel Shelley, Pascale Lherminier, and Géraldine Sarthou
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We investigated the spatial distribution of dissolved Fe during spring 2014, in order to understand the processes influencing the biogeochemical cycle in the North Atlantic. Our results highlighted elevated Fe close to riverine inputs at the Iberian Margin and glacial inputs at the Newfoundland and Greenland margins. Atmospheric deposition appeared to be a minor source of Fe. Convection was an important source of Fe in the Irminger Sea, which was depleted in Fe relative to nitrate.
Tanguy Szekely, Jérôme Gourrion, Sylvie Pouliquen, and Gilles Reverdin
Ocean Sci., 15, 1601–1614, https://doi.org/10.5194/os-15-1601-2019, https://doi.org/10.5194/os-15-1601-2019, 2019
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This study is an attempt to validate the quality of a global temperature and salinity dataset by estimating the effects of measurement errors on the estimated ocean variability. The study shows that the effects of the measurement errors decrease during the quality control process and are almost null for the delayed-time-mode quality-controlled dataset.
Camille Risi, Joseph Galewsky, Gilles Reverdin, and Florent Brient
Atmos. Chem. Phys., 19, 12235–12260, https://doi.org/10.5194/acp-19-12235-2019, https://doi.org/10.5194/acp-19-12235-2019, 2019
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Water molecules can be light (one oxygen atom and two hydrogen atoms) or heavy (one hydrogen atom is replaced by a deuterium atom). These different molecules are called water isotopes. The isotopic composition of water vapor can potentially provide information about physical processes along the water cycle, but the factors controlling it are complex. As a first step, we propose an equation to predict the water vapor isotopic composition near the surface of tropical oceans.
Gilles Reverdin, Nicolas Metzl, Solveig Olafsdottir, Virginie Racapé, Taro Takahashi, Marion Benetti, Hedinn Valdimarsson, Alice Benoit-Cattin, Magnus Danielsen, Jonathan Fin, Aicha Naamar, Denis Pierrot, Kevin Sullivan, Francis Bringas, and Gustavo Goni
Earth Syst. Sci. Data, 10, 1901–1924, https://doi.org/10.5194/essd-10-1901-2018, https://doi.org/10.5194/essd-10-1901-2018, 2018
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This paper presents the SURATLANT data set (SURveillance ATLANTique), consisting of individual data of temperature, salinity, parameters of the carbonate system, nutrients, and water stable isotopes (δ18O and δD) collected mostly from ships of opportunity since 1993 along transects between Iceland and Newfoundland. These data are used to quantify the seasonal cycle and can be used to investigate long-term tendencies in the surface ocean, including of pCO2 and pH.
Gilles Reverdin, Hedinn Valdimarsson, Gael Alory, Denis Diverres, Francis Bringas, Gustavo Goni, Lars Heilmann, Leon Chafik, Tanguy Szekely, and Andrew R. Friedman
Earth Syst. Sci. Data, 10, 1403–1415, https://doi.org/10.5194/essd-10-1403-2018, https://doi.org/10.5194/essd-10-1403-2018, 2018
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We report monthly time series of surface temperature, salinity, and density in the North Atlantic subpolar gyre in 1993–2017 from hydrographical data collected in particular from thermosalinographs onboard selected ships of opportunity. Most of the time, this data set reproduces well the large-scale variability, except for a few seasons with limited sampling, in particular in winter along western Greenland or northeast of Newfoundland in the presence of sea ice.
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Seasonal cycles of biogeochemical fluxes in the Scotia Sea, Southern Ocean: a stable isotope approach
Absence of photophysiological response to iron addition in autumn phytoplankton in the Antarctic sea-ice zone
Optimal parameters for the ocean's nutrient, carbon, and oxygen cycles compensate for circulation biases but replumb the biological pump
Importance of multiple sources of iron for the upper-ocean biogeochemistry over the northern Indian Ocean
Exploring the role of different data types and timescales in the quality of marine biogeochemical model calibration
All about nitrite: exploring nitrite sources and sinks in the eastern tropical North Pacific oxygen minimum zone
Fossil coccolith morphological attributes as a new proxy for deep ocean carbonate chemistry
Reconstructing ocean carbon storage with CMIP6 Earth system models and synthetic Argo observations
Using machine learning and Biogeochemical-Argo (BGC-Argo) floats to assess biogeochemical models and optimize observing system design
The representation of alkalinity and the carbonate pump from CMIP5 to CMIP6 Earth system models and implications for the carbon cycle
North Atlantic patterns of primary production and phenology in two Earth System Models
Model estimates of metazoans' contributions to the biological carbon pump
Tracing differences in iron supply to the Mid-Atlantic Ridge valley between hydrothermal vent sites: implications for the addition of iron to the deep ocean
Nitrite cycling in the primary nitrite maxima of the eastern tropical North Pacific
Hotspots and drivers of compound marine heatwaves and low net primary production extremes
Ecosystem impacts of marine heat waves in the northeast Pacific
Tracing the role of Arctic shelf processes in Si and N cycling and export through the Fram Strait: insights from combined silicon and nitrate isotopes
Controls on the relative abundances and rates of nitrifying microorganisms in the ocean
The response of diazotrophs to nutrient amendment in the South China Sea and western North Pacific
Influence of GEOTRACES data distribution and misfit function choice on objective parameter retrieval in a marine zinc cycle model
Physiological flexibility of phytoplankton impacts modelled chlorophyll and primary production across the North Pacific Ocean
Observation-constrained estimates of the global ocean carbon sink from Earth system models
Early winter barium excess in the southern Indian Ocean as an annual remineralisation proxy (GEOTRACES GIPr07 cruise)
Controlling factors on the global distribution of a representative marine non-cyanobacterial diazotroph phylotype (Gamma A)
Global nutrient cycling by commercially targeted marine fish
Major processes of the dissolved cobalt cycle in the North and equatorial Pacific Ocean
The impact of the South-East Madagascar Bloom on the oceanic CO2 sink
Nitrite regeneration in the oligotrophic Atlantic Ocean
Bridging the gaps between particulate backscattering measurements and modeled particulate organic carbon in the ocean
Biological production in two contrasted regions of the Mediterranean Sea during the oligotrophic period: an estimate based on the diel cycle of optical properties measured by BioGeoChemical-Argo profiling floats
Acidification of the Nordic Seas
Reconstruction of global surface ocean pCO2 using region-specific predictors based on a stepwise FFNN regression algorithm
Biogeochemical controls on ammonium accumulation in the surface layer of the Southern Ocean
Oxygen export to the deep ocean following Labrador Sea Water formation
N2 fixation in the Mediterranean Sea related to the composition of the diazotrophic community and impact of dust under present and future environmental conditions
Dissolution of a submarine carbonate platform by a submerged lake of acidic seawater
Seasonal flux patterns and carbon transport from low-oxygen eddies at the Cape Verde Ocean Observatory: lessons learned from a time series sediment trap study (2009–2016)
Subsurface iron accumulation and rapid aluminum removal in the Mediterranean following African dust deposition
Long-distance particle transport to the central Ionian Sea
Nicole M. Travis, Colette L. Kelly, and Karen L. Casciotti
Biogeosciences, 21, 1985–2004, https://doi.org/10.5194/bg-21-1985-2024, https://doi.org/10.5194/bg-21-1985-2024, 2024
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We conducted experimental manipulations of light level on microbial communities from the primary nitrite maximum. Overall, while individual microbial processes have different directions and magnitudes in their response to increasing light, the net community response is a decline in nitrite production with increasing light. We conclude that while increased light may decrease net nitrite production, high-light conditions alone do not exclude nitrification from occurring in the surface ocean.
Zoë Rebecca van Kemenade, Zeynep Erdem, Ellen Christine Hopmans, Jaap Smede Sinninghe Damsté, and Darci Rush
Biogeosciences, 21, 1517–1532, https://doi.org/10.5194/bg-21-1517-2024, https://doi.org/10.5194/bg-21-1517-2024, 2024
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The California Current system (CCS) hosts the eastern subtropical North Pacific oxygen minimum zone (ESTNP OMZ). This study shows anaerobic ammonium oxidizing (anammox) bacteria cause a loss of bioavailable nitrogen (N) in the ESTNP OMZ throughout the late Quaternary. Anammox occurred during both glacial and interglacial periods and was driven by the supply of organic matter and changes in ocean currents. These findings may have important consequences for biogeochemical models of the CCS.
Cathy Wimart-Rousseau, Tobias Steinhoff, Birgit Klein, Henry Bittig, and Arne Körtzinger
Biogeosciences, 21, 1191–1211, https://doi.org/10.5194/bg-21-1191-2024, https://doi.org/10.5194/bg-21-1191-2024, 2024
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The marine CO2 system can be measured independently and continuously by BGC-Argo floats since numerous pH sensors have been developed to suit these autonomous measurements platforms. By applying the Argo correction routines to float pH data acquired in the subpolar North Atlantic Ocean, we report the uncertainty and lack of objective criteria associated with the choice of the reference method as well the reference depth for the pH correction.
Sabine Mecking and Kyla Drushka
Biogeosciences, 21, 1117–1133, https://doi.org/10.5194/bg-21-1117-2024, https://doi.org/10.5194/bg-21-1117-2024, 2024
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This study investigates whether northeastern North Pacific oxygen changes may be caused by surface density changes in the northwest as water moves along density horizons from the surface into the subsurface ocean. A correlation is found with a lag that about matches the travel time of water from the northwest to the northeast. Salinity is the main driver causing decadal changes in surface density, whereas salinity and temperature contribute about equally to long-term declining density trends.
Takamitsu Ito, Hernan E. Garcia, Zhankun Wang, Shoshiro Minobe, Matthew C. Long, Just Cebrian, James Reagan, Tim Boyer, Christopher Paver, Courtney Bouchard, Yohei Takano, Seth Bushinsky, Ahron Cervania, and Curtis A. Deutsch
Biogeosciences, 21, 747–759, https://doi.org/10.5194/bg-21-747-2024, https://doi.org/10.5194/bg-21-747-2024, 2024
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This study aims to estimate how much oceanic oxygen has been lost and its uncertainties. One major source of uncertainty comes from the statistical gap-filling methods. Outputs from Earth system models are used to generate synthetic observations where oxygen data are extracted from the model output at the location and time of historical oceanographic cruises. Reconstructed oxygen trend is approximately two-thirds of the true trend.
Robert W. Izett, Katja Fennel, Adam C. Stoer, and David P. Nicholson
Biogeosciences, 21, 13–47, https://doi.org/10.5194/bg-21-13-2024, https://doi.org/10.5194/bg-21-13-2024, 2024
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This paper provides an overview of the capacity to expand the global coverage of marine primary production estimates using autonomous ocean-going instruments, called Biogeochemical-Argo floats. We review existing approaches to quantifying primary production using floats, provide examples of the current implementation of the methods, and offer insights into how they can be better exploited. This paper is timely, given the ongoing expansion of the Biogeochemical-Argo array.
Qian Liu, Yingjie Liu, and Xiaofeng Li
Biogeosciences, 20, 4857–4874, https://doi.org/10.5194/bg-20-4857-2023, https://doi.org/10.5194/bg-20-4857-2023, 2023
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In the Southern Ocean, abundant eddies behave opposite to our expectations. That is, anticyclonic (cyclonic) eddies are cold (warm). By investigating the variations of physical and biochemical parameters in eddies, we find that abnormal eddies have unique and significant effects on modulating the parameters. This study fills a gap in understanding the effects of abnormal eddies on physical and biochemical parameters in the Southern Ocean.
France Van Wambeke, Pascal Conan, Mireille Pujo-Pay, Vincent Taillandier, Olivier Crispi, and Elvira Pulido-Villena
EGUsphere, https://doi.org/10.5194/egusphere-2023-2578, https://doi.org/10.5194/egusphere-2023-2578, 2023
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Distribution of phosphomonoesterase (PME) and phosphodiesterase (PDE) activities over the epipelagic zone are described in the eastern Mediterranean Sea, in winter and spring. The type of concentration kinetics obtained for PDE (saturation at 50 µM, high Km, high turnovertimes) compared to those of PME (saturation at 1 µM, low Km, low turnovertimes) are discussed in regard to possible inequal distribution of PDE and PME among organic material size continuum, and accessibility to phosphodiesters.
Caroline Ulses, Claude Estournel, Patrick Marsaleix, Karline Soetaert, Marine Fourrier, Laurent Coppola, Dominique Lefèvre, Franck Touratier, Catherine Goyet, Véronique Guglielmi, Fayçal Kessouri, Pierre Testor, and Xavier Durrieu de Madron
Biogeosciences, 20, 4683–4710, https://doi.org/10.5194/bg-20-4683-2023, https://doi.org/10.5194/bg-20-4683-2023, 2023
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Deep convection plays a key role in the circulation, thermodynamics, and biogeochemical cycles in the Mediterranean Sea, considered to be a hotspot of biodiversity and climate change. In this study, we investigate the seasonal and annual budget of dissolved inorganic carbon in the deep-convection area of the northwestern Mediterranean Sea.
Daniela König and Alessandro Tagliabue
Biogeosciences, 20, 4197–4212, https://doi.org/10.5194/bg-20-4197-2023, https://doi.org/10.5194/bg-20-4197-2023, 2023
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Using model simulations, we show that natural and anthropogenic changes in the global climate leave a distinct fingerprint in the isotopic signatures of iron in the surface ocean. We find that these climate effects on iron isotopes are often caused by the redistribution of iron from different external sources to the ocean, due to changes in ocean currents, and by changes in algal growth, which take up iron. Thus, isotopes may help detect climate-induced changes in iron supply and algal uptake.
Chloé Baumas, Robin Fuchs, Marc Garel, Jean-Christophe Poggiale, Laurent Memery, Frédéric A. C. Le Moigne, and Christian Tamburini
Biogeosciences, 20, 4165–4182, https://doi.org/10.5194/bg-20-4165-2023, https://doi.org/10.5194/bg-20-4165-2023, 2023
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Through the sink of particles in the ocean, carbon (C) is exported and sequestered when reaching 1000 m. Attempts to quantify C exported vs. C consumed by heterotrophs have increased. Yet most of the conducted estimations have led to C demands several times higher than C export. The choice of parameters greatly impacts the results. As theses parameters are overlooked, non-accurate values are often used. In this study we show that C budgets can be well balanced when using appropriate values.
Anna Belcher, Sian F. Henley, Katharine Hendry, Marianne Wootton, Lisa Friberg, Ursula Dallman, Tong Wang, Christopher Coath, and Clara Manno
Biogeosciences, 20, 3573–3591, https://doi.org/10.5194/bg-20-3573-2023, https://doi.org/10.5194/bg-20-3573-2023, 2023
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The oceans play a crucial role in the uptake of atmospheric carbon dioxide, particularly the Southern Ocean. The biological pumping of carbon from the surface to the deep ocean is key to this. Using sediment trap samples from the Scotia Sea, we examine biogeochemical fluxes of carbon, nitrogen, and biogenic silica and their stable isotope compositions. We find phytoplankton community structure and physically mediated processes are important controls on particulate fluxes to the deep ocean.
Asmita Singh, Susanne Fietz, Sandy J. Thomalla, Nicolas Sanchez, Murat V. Ardelan, Sébastien Moreau, Hanna M. Kauko, Agneta Fransson, Melissa Chierici, Saumik Samanta, Thato N. Mtshali, Alakendra N. Roychoudhury, and Thomas J. Ryan-Keogh
Biogeosciences, 20, 3073–3091, https://doi.org/10.5194/bg-20-3073-2023, https://doi.org/10.5194/bg-20-3073-2023, 2023
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Despite the scarcity of iron in the Southern Ocean, seasonal blooms occur due to changes in nutrient and light availability. Surprisingly, during an autumn bloom in the Antarctic sea-ice zone, the results from incubation experiments showed no significant photophysiological response of phytoplankton to iron addition. This suggests that ambient iron concentrations were sufficient, challenging the notion of iron deficiency in the Southern Ocean through extended iron-replete post-bloom conditions.
Benoît Pasquier, Mark Holzer, Matthew A. Chamberlain, Richard J. Matear, Nathaniel L. Bindoff, and François W. Primeau
Biogeosciences, 20, 2985–3009, https://doi.org/10.5194/bg-20-2985-2023, https://doi.org/10.5194/bg-20-2985-2023, 2023
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Modeling the ocean's carbon and oxygen cycles accurately is challenging. Parameter optimization improves the fit to observed tracers but can introduce artifacts in the biological pump. Organic-matter production and subsurface remineralization rates adjust to compensate for circulation biases, changing the pathways and timescales with which nutrients return to the surface. Circulation biases can thus strongly alter the system’s response to ecological change, even when parameters are optimized.
Priyanka Banerjee
Biogeosciences, 20, 2613–2643, https://doi.org/10.5194/bg-20-2613-2023, https://doi.org/10.5194/bg-20-2613-2023, 2023
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This study shows that atmospheric deposition is the most important source of iron to the upper northern Indian Ocean for phytoplankton growth. This is followed by iron from continental-shelf sediment. Phytoplankton increase following iron addition is possible only with high background levels of nitrate. Vertical mixing is the most important physical process supplying iron to the upper ocean in this region throughout the year. The importance of ocean currents in supplying iron varies seasonally.
Iris Kriest, Julia Getzlaff, Angela Landolfi, Volkmar Sauerland, Markus Schartau, and Andreas Oschlies
Biogeosciences, 20, 2645–2669, https://doi.org/10.5194/bg-20-2645-2023, https://doi.org/10.5194/bg-20-2645-2023, 2023
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Global biogeochemical ocean models are often subjectively assessed and tuned against observations. We applied different strategies to calibrate a global model against observations. Although the calibrated models show similar tracer distributions at the surface, they differ in global biogeochemical fluxes, especially in global particle flux. Simulated global volume of oxygen minimum zones varies strongly with calibration strategy and over time, rendering its temporal extrapolation difficult.
John C. Tracey, Andrew R. Babbin, Elizabeth Wallace, Xin Sun, Katherine L. DuRussel, Claudia Frey, Donald E. Martocello III, Tyler Tamasi, Sergey Oleynik, and Bess B. Ward
Biogeosciences, 20, 2499–2523, https://doi.org/10.5194/bg-20-2499-2023, https://doi.org/10.5194/bg-20-2499-2023, 2023
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Nitrogen (N) is essential for life; thus, its availability plays a key role in determining marine productivity. Using incubations of seawater spiked with a rare form of N measurable on a mass spectrometer, we quantified microbial pathways that determine marine N availability. The results show that pathways that recycle N have higher rates than those that result in its loss from biomass and present new evidence for anaerobic nitrite oxidation, a process long thought to be strictly aerobic.
Amanda Gerotto, Hongrui Zhang, Renata Hanae Nagai, Heather M. Stoll, Rubens César Lopes Figueira, Chuanlian Liu, and Iván Hernández-Almeida
Biogeosciences, 20, 1725–1739, https://doi.org/10.5194/bg-20-1725-2023, https://doi.org/10.5194/bg-20-1725-2023, 2023
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Based on the analysis of the response of coccolithophores’ morphological attributes in a laboratory dissolution experiment and surface sediment samples from the South China Sea, we proposed that the thickness shape (ks) factor of fossil coccoliths together with the normalized ks variation, which is the ratio of the standard deviation of ks (σ) over the mean ks (σ/ks), is a robust and novel proxy to reconstruct past changes in deep ocean carbon chemistry.
Katherine E. Turner, Doug M. Smith, Anna Katavouta, and Richard G. Williams
Biogeosciences, 20, 1671–1690, https://doi.org/10.5194/bg-20-1671-2023, https://doi.org/10.5194/bg-20-1671-2023, 2023
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We present a new method for reconstructing ocean carbon using climate models and temperature and salinity observations. To test this method, we reconstruct modelled carbon using synthetic observations consistent with current sampling programmes. Sensitivity tests show skill in reconstructing carbon trends and variability within the upper 2000 m. Our results indicate that this method can be used for a new global estimate for ocean carbon content.
Alexandre Mignot, Hervé Claustre, Gianpiero Cossarini, Fabrizio D'Ortenzio, Elodie Gutknecht, Julien Lamouroux, Paolo Lazzari, Coralie Perruche, Stefano Salon, Raphaëlle Sauzède, Vincent Taillandier, and Anna Teruzzi
Biogeosciences, 20, 1405–1422, https://doi.org/10.5194/bg-20-1405-2023, https://doi.org/10.5194/bg-20-1405-2023, 2023
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Numerical models of ocean biogeochemistry are becoming a major tool to detect and predict the impact of climate change on marine resources and monitor ocean health. Here, we demonstrate the use of the global array of BGC-Argo floats for the assessment of biogeochemical models. We first detail the handling of the BGC-Argo data set for model assessment purposes. We then present 23 assessment metrics to quantify the consistency of BGC model simulations with respect to BGC-Argo data.
Alban Planchat, Lester Kwiatkowski, Laurent Bopp, Olivier Torres, James R. Christian, Momme Butenschön, Tomas Lovato, Roland Séférian, Matthew A. Chamberlain, Olivier Aumont, Michio Watanabe, Akitomo Yamamoto, Andrew Yool, Tatiana Ilyina, Hiroyuki Tsujino, Kristen M. Krumhardt, Jörg Schwinger, Jerry Tjiputra, John P. Dunne, and Charles Stock
Biogeosciences, 20, 1195–1257, https://doi.org/10.5194/bg-20-1195-2023, https://doi.org/10.5194/bg-20-1195-2023, 2023
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Ocean alkalinity is critical to the uptake of atmospheric carbon and acidification in surface waters. We review the representation of alkalinity and the associated calcium carbonate cycle in Earth system models. While many parameterizations remain present in the latest generation of models, there is a general improvement in the simulated alkalinity distribution. This improvement is related to an increase in the export of biotic calcium carbonate, which closer resembles observations.
Jenny Hieronymus, Magnus Hieronymus, Matthias Gröger, Jörg Schwinger, Raffaele Bernadello, Etienne Tourigny, Valentina Sicardi, Itzel Ruvalcaba Baroni, and Klaus Wyser
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-54, https://doi.org/10.5194/bg-2023-54, 2023
Revised manuscript accepted for BG
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Changes in the seasonality of primary production has been examined using daily data from two earth system models covering the period 1750–2100. The daily data made it possible to detect shifts in the day of the year during which the net primary production reaches its peak value. It was found that the day of peak primary production occurs earlier and earlier during the 21st century and that a major change in the time series occurs in the beginning of the 21st century.
Jérôme Pinti, Tim DeVries, Tommy Norin, Camila Serra-Pompei, Roland Proud, David A. Siegel, Thomas Kiørboe, Colleen M. Petrik, Ken H. Andersen, Andrew S. Brierley, and André W. Visser
Biogeosciences, 20, 997–1009, https://doi.org/10.5194/bg-20-997-2023, https://doi.org/10.5194/bg-20-997-2023, 2023
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Large numbers of marine organisms such as zooplankton and fish perform daily vertical migration between the surface (at night) and the depths (in the daytime). This fascinating migration is important for the carbon cycle, as these organisms actively bring carbon to depths where it is stored away from the atmosphere for a long time. Here, we quantify the contributions of different animals to this carbon drawdown and storage and show that fish are important to the biological carbon pump.
Alastair J. M. Lough, Alessandro Tagliabue, Clément Demasy, Joseph A. Resing, Travis Mellett, Neil J. Wyatt, and Maeve C. Lohan
Biogeosciences, 20, 405–420, https://doi.org/10.5194/bg-20-405-2023, https://doi.org/10.5194/bg-20-405-2023, 2023
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Iron is a key nutrient for ocean primary productivity. Hydrothermal vents are a source of iron to the oceans, but the size of this source is poorly understood. This study examines the variability in iron inputs between hydrothermal vents in different geological settings. The vents studied release different amounts of Fe, resulting in plumes with similar dissolved iron concentrations but different particulate concentrations. This will help to refine modelling of iron-limited ocean productivity.
Nicole M. Travis, Colette L. Kelly, Margaret R. Mulholland, and Karen L. Casciotti
Biogeosciences, 20, 325–347, https://doi.org/10.5194/bg-20-325-2023, https://doi.org/10.5194/bg-20-325-2023, 2023
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The primary nitrite maximum is a ubiquitous upper ocean feature where nitrite accumulates, but we still do not understand its formation and the co-occurring microbial processes involved. Using correlative methods and rates measurements, we found strong spatial patterns between environmental conditions and depths of the nitrite maxima, but not the maximum concentrations. Nitrification was the dominant source of nitrite, with occasional high nitrite production from phytoplankton near the coast.
Natacha Le Grix, Jakob Zscheischler, Keith B. Rodgers, Ryohei Yamaguchi, and Thomas L. Frölicher
Biogeosciences, 19, 5807–5835, https://doi.org/10.5194/bg-19-5807-2022, https://doi.org/10.5194/bg-19-5807-2022, 2022
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Compound events threaten marine ecosystems. Here, we investigate the potentially harmful combination of marine heatwaves with low phytoplankton productivity. Using satellite-based observations, we show that these compound events are frequent in the low latitudes. We then investigate the drivers of these compound events using Earth system models. The models share similar drivers in the low latitudes but disagree in the high latitudes due to divergent factors limiting phytoplankton production.
Abigale M. Wyatt, Laure Resplandy, and Adrian Marchetti
Biogeosciences, 19, 5689–5705, https://doi.org/10.5194/bg-19-5689-2022, https://doi.org/10.5194/bg-19-5689-2022, 2022
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Marine heat waves (MHWs) are a frequent event in the northeast Pacific, with a large impact on the region's ecosystems. Large phytoplankton in the North Pacific Transition Zone are greatly affected by decreased nutrients, with less of an impact in the Alaskan Gyre. For small phytoplankton, MHWs increase the spring small phytoplankton population in both regions thanks to reduced light limitation. In both zones, this results in a significant decrease in the ratio of large to small phytoplankton.
Margot C. F. Debyser, Laetitia Pichevin, Robyn E. Tuerena, Paul A. Dodd, Antonia Doncila, and Raja S. Ganeshram
Biogeosciences, 19, 5499–5520, https://doi.org/10.5194/bg-19-5499-2022, https://doi.org/10.5194/bg-19-5499-2022, 2022
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We focus on the exchange of key nutrients for algae production between the Arctic and Atlantic oceans through the Fram Strait. We show that the export of dissolved silicon here is controlled by the availability of nitrate which is influenced by denitrification on Arctic shelves. We suggest that any future changes in the river inputs of silica and changes in denitrification due to climate change will impact the amount of silicon exported, with impacts on Atlantic algal productivity and ecology.
Emily J. Zakem, Barbara Bayer, Wei Qin, Alyson E. Santoro, Yao Zhang, and Naomi M. Levine
Biogeosciences, 19, 5401–5418, https://doi.org/10.5194/bg-19-5401-2022, https://doi.org/10.5194/bg-19-5401-2022, 2022
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We use a microbial ecosystem model to quantitatively explain the mechanisms controlling observed relative abundances and nitrification rates of ammonia- and nitrite-oxidizing microorganisms in the ocean. We also estimate how much global carbon fixation can be associated with chemoautotrophic nitrification. Our results improve our understanding of the controls on nitrification, laying the groundwork for more accurate predictions in global climate models.
Zuozhu Wen, Thomas J. Browning, Rongbo Dai, Wenwei Wu, Weiying Li, Xiaohua Hu, Wenfang Lin, Lifang Wang, Xin Liu, Zhimian Cao, Haizheng Hong, and Dalin Shi
Biogeosciences, 19, 5237–5250, https://doi.org/10.5194/bg-19-5237-2022, https://doi.org/10.5194/bg-19-5237-2022, 2022
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Fe and P are key factors controlling the biogeography and activity of marine N2-fixing microorganisms. We found lower abundance and activity of N2 fixers in the northern South China Sea than around the western boundary of the North Pacific, and N2 fixation rates switched from Fe–P co-limitation to P limitation. We hypothesize the Fe supply rates and Fe utilization strategies of each N2 fixer are important in regulating spatial variability in community structure across the study area.
Claudia Eisenring, Sophy E. Oliver, Samar Khatiwala, and Gregory F. de Souza
Biogeosciences, 19, 5079–5106, https://doi.org/10.5194/bg-19-5079-2022, https://doi.org/10.5194/bg-19-5079-2022, 2022
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Given the sparsity of observational constraints on micronutrients such as zinc (Zn), we assess the sensitivities of a framework for objective parameter optimisation in an oceanic Zn cycling model. Our ensemble of optimisations towards synthetic data with varying kinds of uncertainty shows that deficiencies related to model complexity and the choice of the misfit function generally have a greater impact on the retrieval of model Zn uptake behaviour than does the limitation of data coverage.
Yoshikazu Sasai, Sherwood Lan Smith, Eko Siswanto, Hideharu Sasaki, and Masami Nonaka
Biogeosciences, 19, 4865–4882, https://doi.org/10.5194/bg-19-4865-2022, https://doi.org/10.5194/bg-19-4865-2022, 2022
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We have investigated the adaptive response of phytoplankton growth to changing light, nutrients, and temperature over the North Pacific using two physical-biological models. We compare modeled chlorophyll and primary production from an inflexible control model (InFlexPFT), which assumes fixed carbon (C):nitrogen (N):chlorophyll (Chl) ratios, to a recently developed flexible phytoplankton functional type model (FlexPFT), which incorporates photoacclimation and variable C:N:Chl ratios.
Jens Terhaar, Thomas L. Frölicher, and Fortunat Joos
Biogeosciences, 19, 4431–4457, https://doi.org/10.5194/bg-19-4431-2022, https://doi.org/10.5194/bg-19-4431-2022, 2022
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Estimates of the ocean sink of anthropogenic carbon vary across various approaches. We show that the global ocean carbon sink can be estimated by three parameters, two of which approximate the ocean ventilation in the Southern Ocean and the North Atlantic, and one of which approximates the chemical capacity of the ocean to take up carbon. With observations of these parameters, we estimate that the global ocean carbon sink is 10 % larger than previously assumed, and we cut uncertainties in half.
Natasha René van Horsten, Hélène Planquette, Géraldine Sarthou, Thomas James Ryan-Keogh, Nolwenn Lemaitre, Thato Nicholas Mtshali, Alakendra Roychoudhury, and Eva Bucciarelli
Biogeosciences, 19, 3209–3224, https://doi.org/10.5194/bg-19-3209-2022, https://doi.org/10.5194/bg-19-3209-2022, 2022
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The remineralisation proxy, barite, was measured along 30°E in the southern Indian Ocean during early austral winter. To our knowledge this is the first reported Southern Ocean winter study. Concentrations throughout the water column were comparable to observations during spring to autumn. By linking satellite primary production to this proxy a possible annual timescale is proposed. These findings also suggest possible carbon remineralisation from satellite data on a basin scale.
Zhibo Shao and Ya-Wei Luo
Biogeosciences, 19, 2939–2952, https://doi.org/10.5194/bg-19-2939-2022, https://doi.org/10.5194/bg-19-2939-2022, 2022
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Non-cyanobacterial diazotrophs (NCDs) may be an important player in fixing N2 in the ocean. By conducting meta-analyses, we found that a representative marine NCD phylotype, Gamma A, tends to inhabit ocean environments with high productivity, low iron concentration and high light intensity. It also appears to be more abundant inside cyclonic eddies. Our study suggests a niche differentiation of NCDs from cyanobacterial diazotrophs as the latter prefers low-productivity and high-iron oceans.
Priscilla Le Mézo, Jérôme Guiet, Kim Scherrer, Daniele Bianchi, and Eric Galbraith
Biogeosciences, 19, 2537–2555, https://doi.org/10.5194/bg-19-2537-2022, https://doi.org/10.5194/bg-19-2537-2022, 2022
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This study quantifies the role of commercially targeted fish biomass in the cycling of three important nutrients (N, P, and Fe), relative to nutrients otherwise available in water and to nutrients required by primary producers, and the impact of fishing. We use a model of commercially targeted fish biomass constrained by fish catch and stock assessment data to assess the contributions of fish at the global scale, at the time of the global peak catch and prior to industrial fishing.
Rebecca Chmiel, Nathan Lanning, Allison Laubach, Jong-Mi Lee, Jessica Fitzsimmons, Mariko Hatta, William Jenkins, Phoebe Lam, Matthew McIlvin, Alessandro Tagliabue, and Mak Saito
Biogeosciences, 19, 2365–2395, https://doi.org/10.5194/bg-19-2365-2022, https://doi.org/10.5194/bg-19-2365-2022, 2022
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Dissolved cobalt is present in trace amounts in seawater and is a necessary nutrient for marine microbes. On a transect from the Alaskan coast to Tahiti, we measured seawater concentrations of dissolved cobalt. Here, we describe several interesting features of the Pacific cobalt cycle including cobalt sources along the Alaskan coast and Hawaiian vents, deep-ocean particle formation, cobalt activity in low-oxygen regions, and how our samples compare to a global biogeochemical model’s predictions.
Nicolas Metzl, Claire Lo Monaco, Coraline Leseurre, Céline Ridame, Jonathan Fin, Claude Mignon, Marion Gehlen, and Thi Tuyet Trang Chau
Biogeosciences, 19, 1451–1468, https://doi.org/10.5194/bg-19-1451-2022, https://doi.org/10.5194/bg-19-1451-2022, 2022
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During an oceanographic cruise conducted in January 2020 in the south-western Indian Ocean, we observed very low CO2 concentrations associated with a strong phytoplankton bloom that occurred south-east of Madagascar. This biological event led to a strong regional CO2 ocean sink not previously observed.
Darren R. Clark, Andrew P. Rees, Charissa M. Ferrera, Lisa Al-Moosawi, Paul J. Somerfield, Carolyn Harris, Graham D. Quartly, Stephen Goult, Glen Tarran, and Gennadi Lessin
Biogeosciences, 19, 1355–1376, https://doi.org/10.5194/bg-19-1355-2022, https://doi.org/10.5194/bg-19-1355-2022, 2022
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Measurements of microbial processes were made in the sunlit open ocean during a research cruise (AMT19) between the UK and Chile. These help us to understand how microbial communities maintain the function of remote ecosystems. We find that the nitrogen cycling microbes which produce nitrite respond to changes in the environment. Our insights will aid the development of models that aim to replicate and ultimately project how marine environments may respond to ongoing climate change.
Martí Galí, Marcus Falls, Hervé Claustre, Olivier Aumont, and Raffaele Bernardello
Biogeosciences, 19, 1245–1275, https://doi.org/10.5194/bg-19-1245-2022, https://doi.org/10.5194/bg-19-1245-2022, 2022
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Part of the organic matter produced by plankton in the upper ocean is exported to the deep ocean. This process, known as the biological carbon pump, is key for the regulation of atmospheric carbon dioxide and global climate. However, the dynamics of organic particles below the upper ocean layer are not well understood. Here we compared the measurements acquired by autonomous robots in the top 1000 m of the ocean to a numerical model, which can help improve future climate projections.
Marie Barbieux, Julia Uitz, Alexandre Mignot, Collin Roesler, Hervé Claustre, Bernard Gentili, Vincent Taillandier, Fabrizio D'Ortenzio, Hubert Loisel, Antoine Poteau, Edouard Leymarie, Christophe Penkerc'h, Catherine Schmechtig, and Annick Bricaud
Biogeosciences, 19, 1165–1194, https://doi.org/10.5194/bg-19-1165-2022, https://doi.org/10.5194/bg-19-1165-2022, 2022
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This study assesses marine biological production in two Mediterranean systems representative of vast desert-like (oligotrophic) areas encountered in the global ocean. We use a novel approach based on non-intrusive high-frequency in situ measurements by two profiling robots, the BioGeoChemical-Argo (BGC-Argo) floats. Our results indicate substantial yet variable production rates and contribution to the whole water column of the subsurface layer, typically considered steady and non-productive.
Filippa Fransner, Friederike Fröb, Jerry Tjiputra, Nadine Goris, Siv K. Lauvset, Ingunn Skjelvan, Emil Jeansson, Abdirahman Omar, Melissa Chierici, Elizabeth Jones, Agneta Fransson, Sólveig R. Ólafsdóttir, Truls Johannessen, and Are Olsen
Biogeosciences, 19, 979–1012, https://doi.org/10.5194/bg-19-979-2022, https://doi.org/10.5194/bg-19-979-2022, 2022
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Ocean acidification, a direct consequence of the CO2 release by human activities, is a serious threat to marine ecosystems. In this study, we conduct a detailed investigation of the acidification of the Nordic Seas, from 1850 to 2100, by using a large set of samples taken during research cruises together with numerical model simulations. We estimate the effects of changes in different environmental factors on the rate of acidification and its potential effects on cold-water corals.
Guorong Zhong, Xuegang Li, Jinming Song, Baoxiao Qu, Fan Wang, Yanjun Wang, Bin Zhang, Xiaoxia Sun, Wuchang Zhang, Zhenyan Wang, Jun Ma, Huamao Yuan, and Liqin Duan
Biogeosciences, 19, 845–859, https://doi.org/10.5194/bg-19-845-2022, https://doi.org/10.5194/bg-19-845-2022, 2022
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A predictor selection algorithm was constructed to decrease the predicting error in the surface ocean partial pressure of CO2 (pCO2) mapping by finding better combinations of pCO2 predictors in different regions. Compared with previous research using the same combination of predictors in all regions, using different predictors selected by the algorithm in different regions can effectively decrease pCO2 predicting errors.
Shantelle Smith, Katye E. Altieri, Mhlangabezi Mdutyana, David R. Walker, Ruan G. Parrott, Sedick Gallie, Kurt A. M. Spence, Jessica M. Burger, and Sarah E. Fawcett
Biogeosciences, 19, 715–741, https://doi.org/10.5194/bg-19-715-2022, https://doi.org/10.5194/bg-19-715-2022, 2022
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Ammonium is a crucial yet poorly understood component of the Southern Ocean nitrogen cycle. We attribute our finding of consistently high ammonium concentrations in the winter mixed layer to limited ammonium consumption and sustained ammonium production, conditions under which the Southern Ocean becomes a source of carbon dioxide to the atmosphere. From similar data collected over an annual cycle, we propose a seasonal cycle for ammonium in shallow polar waters – a first for the Southern Ocean.
Jannes Koelling, Dariia Atamanchuk, Johannes Karstensen, Patricia Handmann, and Douglas W. R. Wallace
Biogeosciences, 19, 437–454, https://doi.org/10.5194/bg-19-437-2022, https://doi.org/10.5194/bg-19-437-2022, 2022
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In this study, we investigate oxygen variability in the deep western boundary current in the Labrador Sea from multiyear moored records. We estimate that about half of the oxygen taken up in the interior Labrador Sea by air–sea gas exchange during deep water formation is exported southward the same year. Our results underline the complexity of the oxygen uptake and export in the Labrador Sea and highlight the important role this region plays in supplying oxygen to the deep ocean.
Céline Ridame, Julie Dinasquet, Søren Hallstrøm, Estelle Bigeard, Lasse Riemann, France Van Wambeke, Matthieu Bressac, Elvira Pulido-Villena, Vincent Taillandier, Fréderic Gazeau, Antonio Tovar-Sanchez, Anne-Claire Baudoux, and Cécile Guieu
Biogeosciences, 19, 415–435, https://doi.org/10.5194/bg-19-415-2022, https://doi.org/10.5194/bg-19-415-2022, 2022
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We show that in the Mediterranean Sea spatial variability in N2 fixation is related to the diazotrophic community composition reflecting different nutrient requirements among species. Nutrient supply by Saharan dust is of great importance to diazotrophs, as shown by the strong stimulation of N2 fixation after a simulated dust event under present and future climate conditions; the magnitude of stimulation depends on the degree of limitation related to the diazotrophic community composition.
Matthew P. Humphreys, Erik H. Meesters, Henk de Haas, Szabina Karancz, Louise Delaigue, Karel Bakker, Gerard Duineveld, Siham de Goeyse, Andreas F. Haas, Furu Mienis, Sharyn Ossebaar, and Fleur C. van Duyl
Biogeosciences, 19, 347–358, https://doi.org/10.5194/bg-19-347-2022, https://doi.org/10.5194/bg-19-347-2022, 2022
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A series of submarine sinkholes were recently discovered on Luymes Bank, part of Saba Bank, a carbonate platform in the Caribbean Netherlands. Here, we investigate the waters inside these sinkholes for the first time. One of the sinkholes contained a body of dense, low-oxygen and low-pH water, which we call the
acid lake. We use measurements of seawater chemistry to work out what processes were responsible for forming the acid lake and discuss the consequences for the carbonate platform.
Gerhard Fischer, Oscar E. Romero, Johannes Karstensen, Karl-Heinz Baumann, Nasrollah Moradi, Morten Iversen, Götz Ruhland, Marco Klann, and Arne Körtzinger
Biogeosciences, 18, 6479–6500, https://doi.org/10.5194/bg-18-6479-2021, https://doi.org/10.5194/bg-18-6479-2021, 2021
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Low-oxygen eddies in the eastern subtropical North Atlantic can form an oasis for phytoplankton growth. Here we report on particle flux dynamics at the oligotrophic Cape Verde Ocean Observatory. We observed consistent flux patterns during the passages of low-oxygen eddies. We found distinct flux peaks in late winter, clearly exceeding background fluxes. Our findings suggest that the low-oxygen eddies sequester higher organic carbon than expected for oligotrophic settings.
Matthieu Bressac, Thibaut Wagener, Nathalie Leblond, Antonio Tovar-Sánchez, Céline Ridame, Vincent Taillandier, Samuel Albani, Sophie Guasco, Aurélie Dufour, Stéphanie H. M. Jacquet, François Dulac, Karine Desboeufs, and Cécile Guieu
Biogeosciences, 18, 6435–6453, https://doi.org/10.5194/bg-18-6435-2021, https://doi.org/10.5194/bg-18-6435-2021, 2021
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Phytoplankton growth is limited by the availability of iron in about 50 % of the ocean. Atmospheric deposition of desert dust represents a key source of iron. Here, we present direct observations of dust deposition in the Mediterranean Sea. A key finding is that the input of iron from dust primarily occurred in the deep ocean, while previous studies mainly focused on the ocean surface. This new insight will enable us to better represent controls on global marine productivity in models.
Léo Berline, Andrea Michelangelo Doglioli, Anne Petrenko, Stéphanie Barrillon, Boris Espinasse, Frederic A. C. Le Moigne, François Simon-Bot, Melilotus Thyssen, and François Carlotti
Biogeosciences, 18, 6377–6392, https://doi.org/10.5194/bg-18-6377-2021, https://doi.org/10.5194/bg-18-6377-2021, 2021
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While the Ionian Sea is considered a nutrient-depleted and low-phytoplankton biomass area, it is a crossroad for water mass circulation. In the central Ionian Sea, we observed a strong contrast in particle distribution across a ~100 km long transect. Using remote sensing and Lagrangian simulations, we suggest that this contrast finds its origin in the long-distance transport of particles from the north, west and east of the Ionian Sea, where phytoplankton production was more intense.
Cited articles
Auger, M., Morrow, R., Kestenare, E., Sallée, J.-B., and Cowley, R.:
Southern Ocean in-situ temperature trends over 25 years emerge from interannual variability, Nat. Commun., 12, 514, https://doi.org/10.1038/s41467-020-20781-1, 2021.
Bakker, D. C. E., Nielsdóttir, M. C., Morris, P. J., Venables, H. J., and Watson, A. J.:
The island mass effect and biological carbon uptake for the subantarctic Crozet Archipelago, Deep-Sea Res. Pt. II, 54, 2174–2190, https://doi.org/10.1016/j.dsr2.2007.06.009, 2007.
Bakker, D. C. E., Hoppema, M., Schröder, M., Geibert, W., and de Baar, H. J. W.:
A rapid transition from ice covered
Bakker, D. C. E., Pfeil, B., Landa, C. S., Metzl, N., O'Brien, K. M., Olsen, A., Smith, K., Cosca, C., Harasawa, S., Jones, S. D., Nakaoka, S., Nojiri, Y., Schuster, U., Steinhoff, T., Sweeney, C., Takahashi, T., Tilbrook, B., Wada, C., Wanninkhof, R., Alin, S. R., Balestrini, C. F., Barbero, L., Bates, N. R., Bianchi, A. A., Bonou, F., Boutin, J., Bozec, Y., Burger, E. F., Cai, W.-J., Castle, R. D., Chen, L., Chierici, M., Currie, K., Evans, W., Featherstone, C., Feely, R. A., Fransson, A., Goyet, C., Greenwood, N., Gregor, L., Hankin, S., Hardman-Mountford, N. J., Harlay, J., Hauck, J., Hoppema, M., Humphreys, M. P., Hunt, C. W., Huss, B., Ibánhez, J. S. P., Johannessen, T., Keeling, R., Kitidis, V., Körtzinger, A., Kozyr, A., Krasakopoulou, E., Kuwata, A., Landschützer, P., Lauvset, S. K., Lefèvre, N., Lo Monaco, C., Manke, A., Mathis, J. T., Merlivat, L., Millero, F. J., Monteiro, P. M. S., Munro, D. R., Murata, A., Newberger, T., Omar, A. M., Ono, T., Paterson, K., Pearce, D., Pierrot, D., Robbins, L. L., Saito, S., Salisbury, J., Schlitzer, R., Schneider, B., Schweitzer, R., Sieger, R., Skjelvan, I., Sullivan, K. F., Sutherland, S. C., Sutton, A. J., Tadokoro, K., Telszewski, M., Tuma, M., van Heuven, S. M. A. C., Vandemark, D., Ward, B., Watson, A. J., and Xu, S.:
A multi-decade record of high-quality fCO2 data in version 3 of the Surface Ocean CO2 Atlas (SOCAT), Earth Syst. Sci. Data, 8, 383–413, https://doi.org/10.5194/essd-8-383-2016, 2016.
Bakker, D. C. E., Alin, S. R., Bates, N., Becker, M., Castaño-Primo, R., Cosca, C. E., Cronin, M., Kadono, K., Kozyr, A., Lauvset, S. K., Metzl, N., Munro, D. R., Nakaoka, S., O'Brien, K. M., Ólafsson, J., Olsen, A., Pfeil, B., Pierrot, D., Smith, K., Sutton, A. J., Takahashi, T., Tilbrook, B., Wanninkhof, R., Andersson, A., Atamanchuk, D., Benoit-Cattin, A., Bott, R., Burger, E. F., Cai, W.-J., Cantoni, C., Collins, A., Corredor, J. E., Cronin, M. F., Cross, J. N., Currie, K. I., De Carlo, E. H., DeGrandpre, M. D., Dietrich, C., Emerson, S., Enright, M. P., Evans, W., Feely, R. A., García-Ibáñez, M. I., Gkritzalis, T., Glockzin, M., Hales, B., Hartman, S. E., Hashida, G., Herndon, J., Howden, S. D., Humphreys, M. P., Hunt, C. W., Jones, S. D., Kim, S., Kitidis, V., Landa, C. S., Landschützer, P., Lebon, G. T., Lefèvre, N., Lo Monaco, C., Luchetta, A., Maenner Jones, S., Manke, A. B., Manzello, D. P., Mears, P., Mickett, J., Monacci, N. M., Morell, J. M., Musielewicz, S., Newberger, T., Newton, J., Noakes, S., Noh, J.-H., Nojiri, Y., Ohman, M., Ólafsdóttir, S. R., Omar, A. M., Ono, T., Osborne, J., Plueddemann, A. J., Rehder, G., Sabine, C. L., Salisbury, J. E., Schlitzer, R., Send, U., Skjelvan, I., Sparnocchia, S., Steinhoff, T., Sullivan, K. F., Sutherland, S. C., Sweeney, C., Tadokoro, K., Tanhua, T., Telszewski, M., Tomlinson, M., Tribollet, A., Trull, T., Vandemark, D., Wada, C., Wallace, D. W. R., Weller, R. A., and Woosley, R. J.: Surface Ocean CO2 Atlas Database Version 2020 (SOCATv2020) (NCEI Accession 0210711), NOAA National Centers for Environmental Information [data set], https://doi.org/10.25921/4xkx-ss49, 2020.
Bakker, D. C. E., Alin, S. R., Castaño-Primo, R., Cronin, M., Gkritzalis, T., Kozyr, A., Lauvset, S. K., Metzl, N., Munro, D. R., Nakaoka, S., O'Brien, K. M., Olsen, A., Omar, A. M., Pfeil, B., Pierrot, D., Rodriguez, C., Steinhoff, T., Sutton, A. J., Tilbrook, B., Wanninkhof, R., Willstrand Wranne, A., Ahmed, M., Andersson, A., Apelthun, L. B., Bates, N., Battisti, R., Beaumont, L., Becker, M., Benoit-Cattin, A., Berghoff, C. F., Boutin, J., Burger, E. F., Burgers, T. M., Cantoni, C., Cattrijsse, A., Chierici, M., Cross, J. N., Coppola, L., Cosca, C. E., Currie, K. I., De Carlo, E. H., Else, B., Enright, M. P., Ericson, Y., Evans, W., Feely, R. A., Fiedler, B., Fransson, A., García-Ibáñez, M. I., Gehrung, M., Glockzin, M., González-Dávila, M., Gutekunst, S., Hermes, R., Humphreys, M. P., Hunt, C. W., Ibánhez, J. S. P., Jones, S. D., Kitidis, V., Körtzinger, A., Kosugi, N., Landa, C. S., Landschützer, P., Lefèvre, N., Lo Monaco, C., Luchetta, A., Lutz, V. A., Macovei, V. A., Manke, A. B., Merlivat, L., Millero, F. J., Monacci, N. M., Negri, R. M., Newberger, T., Newton, J., Nickford, S. E., Nojiri, Y., Ohman, M., Ólafsdóttir, S. R., Sweeney, C., Ono, T., Palter, J. B., Papakyriakou, T., Peterson, W. T., Plueddemann, A. J., Qi, D., Rehder, G., Ritschel, M., Rutgersson, A., Sabine, C. L., Salisbury, J. E., Santana-Casiano, J. M., Schlitzer, R., Send, U., Skjelvan, I., Smith, K., Sparnocchia, S., Sullivan, K. F., Sutherland, S. C., Szuts, Z. B., Tadokoro, K., Tanhua, T., Telszewski, Ma., Theetaert, H., Vandemark, D., Voynova, Y. G., Wada, C., Weller, R. A., and Woosley, R. J.: Surface Ocean CO2 Atlas Database Version 2021 (SOCATv2021) (NCEI Accesion 0235360), NOAA National Centers for Envrionmental Information [data set], https://doi.org/10.25921/yg69-jd96, 2021.
Balch, W. M., Bates, N. R., Lam, P. J., Twining, B. S., Rosengard, S. Z., Bowler, B. C., Drapeau, D. T., Garley, R., Lubelczyk, L. C., Mitchell, C., and Rauschenberg, S.:
Factors regulating the Great Calcite Belt in the Southern Ocean and its biogeochemical significance, Global. Biogeochem. Cy., 30, 1124–1144, https://doi.org/10.1002/2016GB005414, 2016.
Bates, N., Astor, Y., Church, M., Currie, K., Dore, J., Gonaález-Dávila, M., Lorenzoni, L., Muller-Karger, F., Olafsson, J., and Santa-Casiano, M.:
A Time-Series View of Changing Ocean Chemistry Due to Ocean Uptake of Anthropogenic CO2 and Ocean Acidification, Oceanography, 27, 126–141, https://doi.org/10.5670/oceanog.2014.16, 2014.
Benson, B. B. and Krause, D.:
The concentration and isotopic fractionation of gases dissolved in freshwater in equilibrium with the atmosphere. 1. Oxygen, Limnol. Oceanogr., 25, 662–671, https://doi.org/10.4319/lo.1980.25.4.0662, 1980.
Blain, S., Quéguiner, B., Armand, L., Belviso, S., Bombled, B., Bopp, L., Bowie, A., Brunet, C., Brussaard, C., Carlotti, F., Christaki, U., Corbière, A., Durand, I., Ebersbach, F., Fuda, J.-L., Garcia, N., Gerringa, L., Griffiths, B., Guigue, C., Guillerm, C., Jacquet, S., Jeandel, C., Laan, P., Lefèvre, D., Lo Monaco, C., Malits, A., Mosseri, J., Obernosterer, I., Park, Y.-H., Picheral, M., Pondaven, P., Remenyi, T., Sandroni, V., Sarthou, G., Savoye, N., Scouarnec, L., Souhaut, M., Thuiller, D., Timmermans, K., Trull, T., Uitz, J., van Beek, P., Veldhuis, M., Vincent, D., Viollier, E., Vong, L., and Wagener, T.:
Effect of natural iron fertilization on carbon sequestration in the Southern Ocean, Nature, 446, 1070–1074, https://doi.org/10.1038/nature05700, 2007.
Blain, S., Quéguiner, B., and Trull, T.:
The natural iron fertilization experiment KEOPS (KErguelen Ocean and Plateau compared Study): An overview, Deep-Sea Res. Pt. II, 55, 559–565, https://doi.org/10.1016/j.dsr2.2008.01.002, 2008.
Bopp, L., Resplandy, L., Orr, J. C., Doney, S. C., Dunne, J. P., Gehlen, M., Halloran, P., Heinze, C., Ilyina, T., Séférian, R., Tjiputra, J., and Vichi, M.:
Multiple stressors of ocean ecosystems in the 21st century: projections with CMIP5 models, Biogeosciences, 10, 6225–6245, https://doi.org/10.5194/bg-10-6225-2013, 2013.
Borrione, I. and Schlitzer, R.:
Distribution and recurrence of phytoplankton blooms around South Georgia, Southern Ocean, Biogeosciences, 10, 217–231, https://doi.org/10.5194/bg-10-217-2013, 2013.
Brewer, P. G.:
Direct observation of the oceanic CO2 increase, Geophys. Res. Lett., 5, 997–1000, https://doi.org/10.1029/GL005i012p00997, 1978.
Broullón, D., Pérez, F. F., Velo, A., Hoppema, M., Olsen, A., Takahashi, T., Key, R. M., Tanhua, T., Santana-Casiano, J. M., and Kozyr, A.:
A global monthly climatology of oceanic total dissolved inorganic carbon: a neural network approach, Earth Syst. Sci. Data, 12, 1725–1743, https://doi.org/10.5194/essd-12-1725-2020, 2020.
Brown, M. S., Munro, D. R., Feehan, C. J., Sweeney, C., Ducklow, H. W., and Schofield, O. M.:
Enhanced oceanic CO2 uptake along the rapidly changing West Antarctic Peninsula, Nat. Clim. Change, 9, 678–683, https://doi.org/10.1038/s41558-019-0552-3, 2019.
Bushinsky, S. M., Landschützer, P., Rödenbeck, C., Gray, A. R., Baker, D., Mazloff, M. R., Resplandy, L., Johnson, K. S., and Sarmiento, J. L.:
Reassessing Southern Ocean Air-Sea CO2 Flux Estimates With the Addition of Biogeochemical Float Observations, Global. Biogeochem. Cy., 33, 1370–1388, https://doi.org/10.1029/2019GB006176, 2019.
Canadell, J. G., Monteiro, P. M. S., Costa, M. H., Cotrim da Cunha, L., Cox, P. M., Eliseev, A. V., Henson, S., Ishii, M., Jaccard, S.,
Koven, C., Lohila, A., Patra, P. K., Piao, S., Rogelj, J., Syampungani, S., Zaehle, S., and Zickfeld, K.: Global Carbon and
other Biogeochemical Cycles and Feedbacks, in: Climate Change 2021: The Physical Science Basis. Contribution of
Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Masson-Delmotte, V., Zhai, P., Pirani, A., Connors, S. L., Péan, C., Berger, S., Caud, N., Chen, Y., Goldfarb, L., Gomis, M. I., Huang, M., Leitzell, K., Lonnoy, E., Matthews, J. B. R., Maycock, T. K., Waterfield, T., Yelekçi, O., Yu, R., and Zhou, B., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 673–816, 2021.
Carpenter, J. H.:
The Accuracy of the Winkler Method for Dissolved Oxygen Analysis, Limnol. Oceanogr., 10, 135–140, https://doi.org/10.4319/lo.1965.10.1.0135, 1965.
Chau, T. T. T., Gehlen, M., and Chevallier, F.:
QUALITY INFORMATION DOCUMENT for Global Ocean Surface Carbon Product MULTIOBS_GLO_BIO_CARBON_SURFACE_REP_015_008, Res. Rap. Lab. Sci. Clim. Environ., 25, https://hal.archives-ouvertes.fr/hal-02957656 (last access: 27 January 2022), 2020.
Chau, T. T. T., Gehlen, M., and Chevallier, F.:
A seamless ensemble-based reconstruction of surface ocean pCO2 and air–sea CO2 fluxes over the global coastal and open oceans, Biogeosciences, 19, 1087–1109, https://doi.org/10.5194/bg-19-1087-2022, 2022.
Chen, G.-T. and Millero, F. J.:
Gradual increase of oceanic CO2, Nature, 277, 205, https://doi.org/10.1038/277205a0, 1979.
Copin-Montegut, C.:
A new formula for the effect of temperature on the partial pressure of CO2 in seawater, Mar. Chem., 25, 29–37, https://doi.org/10.1016/0304-4203(88)90012-6, 1988.
Copin-Montegut, C.:
A new formula for the effect of temperature on the partial pressure of CO2 in seawater, Corrigendum, Mar. Chem., 27, 143–144, https://doi.org/10.1016/0304-4203(89)90034-0, 1989.
Coverly, S. C., Aminot, A., and Kérouel, R.:
Nutrients in Seawater Using Segmented Flow Analysis, in: Practical Guidelines for the Analysis of Seawater, 1st Edn., CRC Press, 143–178, 2009.
de Baar, H. J. W., Boyd, P. W., Coale, K. H., Landry, M. R., Tsuda, A., Assmy, P., Bakker, D. C. E., Bozec, Y., Barber, R. T., Brzezinski, M. A., Buesseler, K. O., Boyé, M., Croot, P. L., Gervais, F., Gorbunov, M. Y., Harrison, P. J., Hiscock, W. T., Laan, P., Lancelot, C., Law, C. S., Levasseur, M., Marchetti, A., Millero, F. J., Nishioka, J., Nojiri, Y., Oijen, T. van, Riebesell, U., Rijkenberg, M. J. A., Saito, H., Takeda, S., Timmermans, K. R., Veldhuis, M. J. W., Waite, A. M., and Wong, C.-S.:
Synthesis of iron fertilization experiments: From the Iron Age in the Age of Enlightenment, J. Geophys. Res.-Oceans, 110, C09S16, https://doi.org/10.1029/2004JC002601, 2005.
Dickson, A. G.:
Standard potential of the reaction: AgCl(s) +
Dickson, A. G. and Millero, F. J.:
A comparison of the equilibrium constants for the dissociation of carbonic acid in seawater media, Deep-Sea Res., 34, 1733–1743, https://doi.org/10.1016/0198-0149(87)90021-5, 1987.
Doney, S. C., Fabry, V. J., Feely, R. A., and Kleypas, J. A.:
Ocean Acidification: The Other CO2 Problem, Annu. Rev. Mar. Sci., 1, 169–192, https://doi.org/10.1146/annurev.marine.010908.163834, 2009.
Edmond, J. M.:
High precision determination of titration alkalinity and total carbon dioxide content of sea water by potentiometric titration, Deep Sea Res. Oceanogr. Abstr., 17, 737–750, https://doi.org/10.1016/0011-7471(70)90038-0, 1970.
Fay, A. R. and McKinley, G. A.:
Global trends in surface ocean pCO2 from in situ data, Global. Biogeochem. Cy., 27, 541–557, https://doi.org/10.1002/gbc.20051, 2013.
Fay, A. R. and McKinley, G. A.:
Global open-ocean biomes: mean and temporal variability, Earth Syst. Sci. Data, 6, 273–284, https://doi.org/10.5194/essd-6-273-2014, 2014.
Fay, A. R., Lovenduski, N. S., McKinley, G. A., Munro, D. R., Sweeney, C., Gray, A. R., Landschützer, P., Stephens, B. B., Takahashi, T., and Williams, N.:
Utilizing the Drake Passage Time-series to understand variability and change in subpolar Southern Ocean pCO2, Biogeosciences, 15, 3841–3855, https://doi.org/10.5194/bg-15-3841-2018, 2018.
Freeman, N. M. and Lovenduski, N. S.:
Decreased calcification in the Southern Ocean over the satellite record, Geophys. Res. Lett., 42, 1834–1840, https://doi.org/10.1002/2014GL062769, 2015.
Friis, K., Körtzinger, A., and Wallace, D. W. R.:
The salinity normalization of marine inorganic carbon chemistry data, Geophys. Res. Lett., 30, 1085, https://doi.org/10.1029/2002GL015898, 2003.
GLODAP: Global Ocean Data Analysis Project, http://www.glodap.info, last access: 23 March 2022.
Gray, A. R., Johnson, K. S., Bushinsky, S. M., Riser, S. C., Russell, J. L., Talley, L. D., Wanninkhof, R., Williams, N. L., and Sarmiento, J. L.:
Autonomous Biogeochemical Floats Detect Significant Carbon Dioxide Outgassing in the High-Latitude Southern Ocean, Geophys. Res. Lett., 45, 9049–9057, https://doi.org/10.1029/2018GL078013, 2018.
Gregg, W. W. and Rousseaux, C. S.:
Decadal trends in global pelagic ocean chlorophyll: A new assessment integrating multiple satellites, in situ data, and models, J. Geophys. Res.-Oceans, 119, 5921–5933, https://doi.org/10.1002/2014JC010158, 2014.
Gregor, L. and Gruber, N.:
OceanSODA-ETHZ: a global gridded data set of the surface ocean carbonate system for seasonal to decadal studies of ocean acidification, Earth Syst. Sci. Data, 13, 777–808, https://doi.org/10.5194/essd-13-777-2021, 2021.
Gregor, L., Kok, S., and Monteiro, P. M. S.:
Interannual drivers of the seasonal cycle of CO2 in the Southern Ocean, Biogeosciences, 15, 2361–2378, https://doi.org/10.5194/bg-15-2361-2018, 2018.
Gruber, N., Clement, D., Carter, B. R., Feely, R. A., Heuven, S. van, Hoppema, M., Ishii, M., Key, R. M., Kozyr, A., Lauvset, S. K., Lo Monaco, C., Mathis, J. T., Murata, A., Olsen, A., Perez, F. F., Sabine, C. L., Tanhua, T., and Wanninkhof, R.:
The oceanic sink for anthropogenic CO2 from 1994 to 2007, Science, 363, 1193–1199, https://doi.org/10.1126/science.aau5153, 2019a.
Gruber, N., Landschützer, P., and Lovenduski, N. S.:
The Variable Southern Ocean Carbon Sink, Annu. Rev. Mar. Sci., 11, 159–186, https://doi.org/10.1146/annurev-marine-121916-063407, 2019b.
Hartmann, D. L., Klein Tank, A. M. G., Rusticucci, M., Alexander, L. V., Brönnimann, S., Charabi, Y., Dentener, F. J., Dlugokencky, E. J., Easterling, D. R., Kaplan, A., Soden, B. J., Thorne, P. W., Wild, M., and Zhai, P. M.:
Observations: Atmosphere and Surface, in: Climate Change 2013: The Physical Science Basis, Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Stocker, T. F., Qin, D., Plattner, G.-K., Tignor, M., Allen, S. K., Boschung, J., Nauels, A., Xia, Y., Bex, V., and Midgley, P. M., Cambridge University Press, Cambridge, UK and New York, NY, USA, 159–254, https://doi.org/10.1017/CBO9781107415324.008, 2013.
Hauck, J., Völker, C., Wang, T., Hoppema, M., Losch, M., and Wolf-Gladrow, D. A.:
Seasonally different carbon flux changes in the Southern Ocean in response to the southern annular mode, Global. Biogeochem. Cy., 27, 1236–1245, https://doi.org/10.1002/2013GB004600, 2013.
Hauck, J., Zeising, M., Le Quéré, C., Gruber, N., Bakker, D. C. E., Bopp, L., Chau, T. T. T., Gürses, Ö., Ilyina, T., Landschützer, P., Lenton, A., Resplandy, L., Rödenbeck, C., Schwinger, J., and Séférian, R.:
Consistency and Challenges in the Ocean Carbon Sink Estimate for the Global Carbon Budget, Front. Mar. Sci., 7, 852, https://doi.org/10.3389/fmars.2020.571720, 2020.
Hauri, C., Friedrich, T., and Timmermann, A.:
Abrupt onset and prolongation of aragonite undersaturation events in the Southern Ocean, Nat. Clim. Change, 6, 172–176, https://doi.org/10.1038/nclimate2844, 2016.
Iida, Y., Takatani, Y., Kojima, A., and Ishii, M.:
Global trends of ocean CO2 sink and ocean acidification: an observation-based reconstruction of surface ocean inorganic carbon variables, J. Oceanogr., 77, 323–358, https://doi.org/10.1007/s10872-020-00571-5, 2021.
Ishii, M., Inoue, H. Y., Matsueda, H., and Tanoue, E.:
Close coupling between seasonal biological production and dynamics of dissolved inorganic carbon in the Indian Ocean sector and the western Pacific Ocean sector of the Antarctic Ocean, Deep-Sea Res., 45, 1187–1209, https://doi.org/10.1016/S0967-0637(98)00010-7, 1998.
Jabaud-Jan, A., Metzl, N., Brunet, C., Poisson, A., and Schauer, B.:
Interannual variability of the carbon dioxide system in the southern Indian Ocean (20∘ S–60∘ S): The impact of a warm anomaly in austral summer 1998, Global. Biogeochem. Cy., 18, https://doi.org/10.1029/2002GB002017, 2004.
Jiang, L.-Q., Carter, B. R., Feely, R. A., Lauvset, S. K., and Olsen, A.:
Surface ocean pH and buffer capacity: past, present and future, Sci. Rep.-UK, 9, 1–11, https://doi.org/10.1038/s41598-019-55039-4, 2019.
Jones, E. M., Bakker, D. C. E., Venables, H. J., and Watson, A. J.:
Dynamic seasonal cycling of inorganic carbon downstream of South Georgia, Southern Ocean, Deep-Sea Res. Pt. II, 59–60, 25–35, https://doi.org/10.1016/j.dsr2.2011.08.001, 2012.
Jouandet, M. P., Blain, S., Metzl, N., Brunet, C., Trull, T. W., and Obernosterer, I.:
A seasonal carbon budget for a naturally iron-fertilized bloom over the Kerguelen Plateau in the Southern Ocean, Deep-Sea Res. Pt. II, 55, 856–867, https://doi.org/10.1016/j.dsr2.2007.12.037, 2008.
Keeling, C. D., Brix, H., and Gruber, N.:
Seasonal and long-term dynamics of the upper ocean carbon cycle at Station ALOHA near Hawaii, Global. Biogeochem. Cy., 18, GB4006, https://doi.org/10.1029/2004GB002227, 2004.
Keppler, L. and Landschützer, P.:
Regional Wind Variability Modulates the Southern Ocean Carbon Sink, Sci. Rep.-UK, 9, 7384, https://doi.org/10.1038/s41598-019-43826-y, 2019.
Kessler, A. and Tjiputra, J.:
The Southern Ocean as a constraint to reduce uncertainty in future ocean carbon sinks, Earth Syst. Dynam., 7, 295–312, https://doi.org/10.5194/esd-7-295-2016, 2016.
Key, R. M., Olsen, A., van Heuven, S., Lauvset, S. K., Velo, A., Lin, X., Schirnick, C., Kozyr, A., Tanhua, T., Hoppema, M., Jutterström, S., Steinfeldt, R., Jeansson, E., Ishii, M., Perez, F. F., and Suzuki, T.: Global Ocean Data Analysis Project, Version 2 (GLODAPv2), ORNL/CDIAC-162, ND-P093. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, US Department of Energy, Oak Ridge, Tennessee, 2015.
Khatiwala, S., Primeau, F., and Hall, T.:
Reconstruction of the history of anthropogenic CO2 concentrations in the ocean, Nature, 462, 346–349, https://doi.org/10.1038/nature08526, 2009.
Körtzinger, A., Mintrop, L., and Duinker, J. C.:
On the penetration of anthropogenic CO2 into the North Atlantic Ocean, J. Geophys. Res.-Oceans, 103, 18681–18689, https://doi.org/10.1029/98JC01737, 1998.
Körtzinger, A., Hedges, J. I., and Quay, P. D.:
Redfield ratios revisited: Removing the biasing effect of anthropogenic CO2, Limnol. Oceanogr., 46, 964–970, https://doi.org/10.4319/lo.2001.46.4.0964, 2001.
Kwiatkowski, L., Torres, O., Bopp, L., Aumont, O., Chamberlain, M., Christian, J. R., Dunne, J. P., Gehlen, M., Ilyina, T., John, J. G., Lenton, A., Li, H., Lovenduski, N. S., Orr, J. C., Palmieri, J., Santana-Falcón, Y., Schwinger, J., Séférian, R., Stock, C. A., Tagliabue, A., Takano, Y., Tjiputra, J., Toyama, K., Tsujino, H., Watanabe, M., Yamamoto, A., Yool, A., and Ziehn, T.:
Twenty-first century ocean warming, acidification, deoxygenation, and upper-ocean nutrient and primary production decline from CMIP6 model projections, Biogeosciences, 17, 3439–3470, https://doi.org/10.5194/bg-17-3439-2020, 2020.
Landschützer, P., Gruber, N., Haumann, F. A., Rödenbeck, C., Bakker, D. C. E., Heuven, S. van, Hoppema, M., Metzl, N., Sweeney, C., Takahashi, T., Tilbrook, B., and Wanninkhof, R.:
The reinvigoration of the Southern Ocean carbon sink, Science, 349, 1221–1224, https://doi.org/10.1126/science.aab2620, 2015.
Landschützer, P., Gruber, N., and Bakker, D. C. E.:
Decadal variations and trends of the global ocean carbon sink, Global. Biogeochem. Cy., 30, 1396–1417, https://doi.org/10.1002/2015GB005359, 2016.
Lauvset, S. K., Gruber, N., Landschützer, P., Olsen, A., and Tjiputra, J.:
Trends and drivers in global surface ocean pH over the past 3 decades, Biogeosciences, 12, 1285–1298, https://doi.org/10.5194/bg-12-1285-2015, 2015.
Le Quéré, C., Rödenbeck, C., Buitenhuis, E. T., Conway, T. J., Langenfelds, R., Gomez, A., Labuschagne, C., Ramonet, M., Nakazawa, T., Metzl, N., Gillett, N., and Heimann, M.:
Saturation of the Southern Ocean CO2 Sink Due to Recent Climate Change, Science, 316, 1735–1738, https://doi.org/10.1126/science.1136188, 2007.
Lee, K., Tong, L. T., Millero, F. J., Sabine, C. L., Dickson, A. G., Goyet, C., Park, G.-H., Wanninkhof, R., Feely, R. A., and Key, R. M.:
Global relationships of total alkalinity with salinity and temperature in surface waters of the world's oceans, Geophys. Res. Lett., 33, L19605, https://doi.org/10.1029/2006GL027207, 2006.
Lenton, A. and Matear, R. J.:
Role of the Southern Annular Mode (SAM) in Southern Ocean CO2 uptake, Global. Biogeochem. Cy., 21, GB2016, https://doi.org/10.1029/2006GB002714, 2007.
Lenton, A., Codron, F., Bopp, L., Metzl, N., Cadule, P., Tagliabue, A., and Le Sommer, J.:
Stratospheric ozone depletion reduces ocean carbon uptake and enhances ocean acidification, Geophys. Res. Lett., 36, L12606, https://doi.org/10.1029/2009GL038227, 2009.
Lenton, A., Metzl, N., Takahashi, T., Kuchinke, M., Matear, R. J., Roy, T., Sutherland, S. C., Sweeney, C., and Tilbrook, B.:
The observed evolution of oceanic pCO2 and its drivers over the last two decades, Global. Biogeochem. Cy., 26, GB2021, https://doi.org/10.1029/2011GB004095, 2012.
Lenton, A., Tilbrook, B., Law, R. M., Bakker, D., Doney, S. C., Gruber, N., Ishii, M., Hoppema, M., Lovenduski, N. S., Matear, R. J., McNeil, B. I., Metzl, N., Mikaloff Fletcher, S. E., Monteiro, P. M. S., Rödenbeck, C., Sweeney, C., and Takahashi, T.:
Sea–air CO2 fluxes in the Southern Ocean for the period 1990–2009, Biogeosciences, 10, 4037–4054, https://doi.org/10.5194/bg-10-4037-2013, 2013.
Leseurre, C., Lo Monaco, C., Reverdin, G., Metzl, N., Fin, J., Olafsdottir, S., and Racapé, V.:
Ocean carbonate system variability in the North Atlantic Subpolar surface water (1993–2017), Biogeosciences, 17, 2553–2577, https://doi.org/10.5194/bg-17-2553-2020, 2020.
Lewis, E., Wallace, D., and Allison, L. J.:
Program developed for CO2 system calculations, Brookhaven National Lab., Dept. of Applied Science, Upton, NY (USA), Oak Ridge National Lab., Carbon Dioxide Information Analysis Center, TN (USA), https://doi.org/10.2172/639712, 1998.
Lo Monaco, C., Metzl, N., Poisson, A., Brunet, C., and Schauer, B.:
Anthropogenic CO2 in the Southern Ocean: Distribution and inventory at the Indian-Atlantic boundary (World Ocean Circulation Experiment line I6), J. Geophys. Res.-Oceans, 110, 1–18, https://doi.org/10.1029/2004JC002643, 2005a.
Lo Monaco, C., Goyet, C., Metzl, N., Poisson, A., and Touratier, F.:
Distribution and inventory of anthropogenic CO2 in the Southern Ocean: Comparison of three data-based methods, J. Geophys. Res.-Oceans, 110, C09S02, https://doi.org/10.1029/2004JC002571, 2005b.
Lo Monaco, C., Álvarez, M., Key, R. M., Lin, X., Tanhua, T., Tilbrook, B., Bakker, D. C. E., van Heuven, S., Hoppema, M., Metzl, N., Ríos, A. F., Sabine, C. L., and Velo, A.:
Assessing the internal consistency of the CARINA database in the Indian sector of the Southern Ocean, Earth Syst. Sci. Data, 2, 51–70, https://doi.org/10.5194/essd-2-51-2010, 2010.
Lo Monaco, C., Metzl, N., D'Ovidio, F., Llort, J., and Ridame, C.:
Rapid establishment of the CO2 sink associated with Kerguelen's bloom observed during the KEOPS2/OISO20 cruise, Biogeosciences Discuss., 11, 17543–17578, https://doi.org/10.5194/bgd-11-17543-2014, 2014.
Lo Monaco, C., Metzl, N., Fin, J., Mignon, C., Cuet, P., Douville, E., Gehlen, M., Chau, T. T. T., and Tribollet, A.:
Distribution and long-term change of the sea surface carbonate system in the Mozambique Channel (1963–2019), Deep-Sea Res. Pt. II, 186–188, 104936, https://doi.org/10.1016/j.dsr2.2021.104936, 2021.
Long, M. C., Stephens, B. B., McKain, K., Sweeney, C., Keeling, R. F., Kort, E. A., Morgan, E. J., Bent, J. D., Chandra, N., Chevallier, F., Commane, R., Daube, B. C., Krummel, P. B., Loh, Z., Luijkx, I. T., Munro, D., Patra, P., Peters, W., Ramonet, M., Rödenbeck, C., Stavert, A., Tans, P., and Wofsy, S. C.:
Strong Southern Ocean carbon uptake evident in airborne observations, Science, 374, 1275–1280, https://doi.org/10.1126/science.abi4355, 2021.
Lourantou, A. and Metzl, N.:
Decadal evolution of carbon sink within a strong bloom area in the subantarctic zone, Geophys. Res. Lett., 38, 1–7, https://doi.org/10.1029/2011GL049614, 2011.
Lovenduski, N. S., Gruber, N., Doney, S. C., and Lima, I. D.:
Enhanced CO2 outgassing in the Southern Ocean from a positive phase of the Southern Annular Mode, Global. Biogeochem. Cy., 21, GB2026, https://doi.org/10.1029/2006GB002900, 2007.
Mackay, N. and Watson, A.:
Winter Air–Sea CO2 Fluxes Constructed From Summer Observations of the Polar Southern Ocean Suggest Weak Outgassing, J. Geophys. Res.-Oceans, 126, e2020JC016600, https://doi.org/10.1029/2020JC016600, 2021.
Mahieu, L., Lo Monaco, C., Metzl, N., Fin, J., and Mignon, C.:
Variability and stability of anthropogenic CO2 in Antarctic Bottom Water observed in the Indian sector of the Southern Ocean, 1978–2018, Ocean Sci., 16, 1559–1576, https://doi.org/10.5194/os-16-1559-2020, 2020.
Martin, J. H., Fitzwater, S. E., and Gordon, R. M.:
Iron deficiency limits phytoplankton growth in Antarctic waters, Global. Biogeochem. Cy., 4, 5–12, https://doi.org/10.1029/GB004i001p00005, 1990.
McNeil, B. I. and Matear, R. J.:
Southern Ocean acidification: A tipping point at 450-ppm atmospheric CO2, P. Natl. Acad. Sci. USA, 105, 18860–18864, https://doi.org/10.1073/pnas.0806318105, 2008.
McNeil, B. I., Tilbrook, B., and Matear, R. J.:
Accumulation and uptake of anthropogenic CO2 in the Southern Ocean, south of Australia between 1968 and 1996, J. Geophys. Res.-Oceans, 106, 31431–31445, https://doi.org/10.1029/2000JC000331, 2001.
Mehrbach, C., Culberson, C. H., Hawley, J. E., and Pytkowicx, R. M.:
Measurement of the Apparent Dissociation Constants of Carbonic Acid in Seawater at Atmospheric Pressure1, Limnol. Oceanogr., 18, 897–907, https://doi.org/10.4319/lo.1973.18.6.0897, 1973.
Metzl, N.:
Decadal increase of oceanic carbon dioxide in Southern Indian Ocean surface waters (1991–2007), Deep-Sea Res. Pt. II, 56, 607–619, https://doi.org/10.1016/j.dsr2.2008.12.007, 2009.
Metzl, N., Brunet, C., Jabaud-Jan, A., Poisson, A., and Schauer, B.:
Summer and winter air–sea CO2 fluxes in the Southern Ocean, Deep-Sea Res., 53, 1548–1563, https://doi.org/10.1016/j.dsr.2006.07.006, 2006.
Midorikawa, T., Ishii, M., Saito, S., Sasano, D., Kosugi, N., Motoi, T., Kamiya, H., Nakadate, A., Nemoto, K., and Inoue, H. Y.:
Decreasing pH trend estimated from 25-yr time series of carbonate parameters in the western North Pacific, Tellus B, 62, 649–659, https://doi.org/10.1111/j.1600-0889.2010.00474.x, 2010.
Midorikawa, T., Inoue, H. Y., Ishii, M., Sasano, D., Kosugi, N., Hashida, G., Nakaoka, S., and Suzuki, T.:
Decreasing pH trend estimated from 35-year time series of carbonate parameters in the Pacific sector of the Southern Ocean in summer, Deep-Sea Res., 61, 131–139, https://doi.org/10.1016/j.dsr.2011.12.003, 2012.
Millero, F. J., Lee, K., and Roche, M.:
Distribution of alkalinity in the surface waters of the major oceans, Mar. Chem., 60, 111–130, https://doi.org/10.1016/S0304-4203(97)00084-4, 1998.
Minas, H. and Minas, M.:
Net community production in high nutrient-low chlorophyll waters of the tropical and antarctic oceans – grazing vs iron hypothesis, Oceanol. Acta, 15, 145–162, 1992.
Mongwe, N. P., Vichi, M., and Monteiro, P. M. S.:
The seasonal cycle of pCO2 and CO2 fluxes in the Southern Ocean: diagnosing anomalies in CMIP5 Earth system models, Biogeosciences, 15, 2851–2872, https://doi.org/10.5194/bg-15-2851-2018, 2018.
Moore, J. K. and Abbott, M. R.:
Phytoplankton chlorophyll distributions and primary production in the Southern Ocean, J. Geophys. Res.-Oceans, 105, 28709–28722, https://doi.org/10.1029/1999JC000043, 2000.
Munro, D. R., Lovenduski, N. S., Takahashi, T., Stephens, B. B., Newberger, T., and Sweeney, C.:
Recent evidence for a strengthening CO2 sink in the Southern Ocean from carbonate system measurements in the Drake Passage (2002–2015), Geophys. Res. Lett., 42, 7623–7630, https://doi.org/10.1002/2015GL065194, 2015.
Murphy, J. and Riley, J. P.:
A modified single solution method for the determination of phosphate in natural waters, Anal. Chim. Acta, 27, 31–36, https://doi.org/10.1016/S0003-2670(00)88444-5, 1962.
NOAA: The OISO Lines, NOAA [data set], https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/OISO.html, last access: 30 April 2020.
Olsen, A., Key, R. M., van Heuven, S., Lauvset, S. K., Velo, A., Lin, X., Schirnick, C., Kozyr, A., Tanhua, T., Hoppema, M., Jutterström, S., Steinfeldt, R., Jeansson, E., Ishii, M., Pérez, F. F., and Suzuki, T.:
The Global Ocean Data Analysis Project version 2 (GLODAPv2) – an internally consistent data product for the world ocean, Earth Syst. Sci. Data, 8, 297–323, https://doi.org/10.5194/essd-8-297-2016, 2016.
Olsen, A., Lange, N., Key, R. M., Tanhua, T., Álvarez, M., Becker, S., Bittig, H. C., Carter, B. R., Cotrim da Cunha, L., Feely, R. A., van Heuven, S., Hoppema, M., Ishii, M., Jeansson, E., Jones, S. D., Jutterström, S., Karlsen, M. K., Kozyr, A., Lauvset, S. K., Lo Monaco, C., Murata, A., Pérez, F. F., Pfeil, B., Schirnick, C., Steinfeldt, R., Suzuki, T., Telszewski, M., Tilbrook, B., Velo, A., and Wanninkhof, R.:
GLODAPv2.2019 – an update of GLODAPv2, Earth Syst. Sci. Data, 11, 1437–1461, https://doi.org/10.5194/essd-11-1437-2019, 2019.
Orr, J. C., Fabry, V. J., Aumont, O., Bopp, L., Doney, S. C., Feely, R. A., Gnanadesikan, A., Gruber, N., Ishida, A., Joos, F., Key, R. M., Lindsay, K., Maier-Reimer, E., Matear, R., Monfray, P., Mouchet, A., Najjar, R. G., Plattner, G.-K., Rodgers, K. B., Sabine, C. L., Sarmiento, J. L., Schlitzer, R., Slater, R. D., Totterdell, I. J., Weirig, M.-F., Yamanaka, Y., and Yool, A.:
Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms, Nature, 437, 681–686, https://doi.org/10.1038/nature04095, 2005.
Orr, J. C., Epitalon, J.-M., Dickson, A. G., and Gattuso, J.-P.:
Routine uncertainty propagation for the marine carbon dioxide system, Mar. Chem., 207, 84–107, https://doi.org/10.1016/j.marchem.2018.10.006, 2018.
Pardo, P. C., Pérez, F. F., Khatiwala, S., and Ríos, A. F.:
Anthropogenic CO2 estimates in the Southern Ocean: Storage partitioning in the different water masses, Prog. Oceanogr., 120, 230–242, https://doi.org/10.1016/j.pocean.2013.09.005, 2014.
Pardo, P. C., Tilbrook, B., Langlais, C., Trull, T. W., and Rintoul, S. R.:
Carbon uptake and biogeochemical change in the Southern Ocean, south of Tasmania, Biogeosciences, 14, 5217–5237, https://doi.org/10.5194/bg-14-5217-2017, 2017.
Park, Y.-H., Gamberoni, L., and Charriaud, E.:
Frontal structure, water masses, and circulation in the Crozet Basin, J. Geophys. Res.-Oceans, 98, 12361–12385, https://doi.org/10.1029/93JC00938, 1993.
Pauthenet, E., Roquet, F., Madec, G., Guinet, C., Hindell, M., McMahon, C. R., Harcourt, R., and Nerini, D.:
Seasonal Meandering of the Polar Front Upstream of the Kerguelen Plateau, Geophys. Res. Lett., 45, 9774–9781, https://doi.org/10.1029/2018GL079614, 2018.
Pellichero, V., Boutin, J., Claustre, H., Merlivat, L., Sallée, J.-B., and Blain, S.:
Relaxation of Wind Stress Drives the Abrupt Onset of Biological Carbon Uptake in the Kerguelen Bloom: A Multisensor Approach, Geophys. Res. Lett., 47, e2019GL085992, https://doi.org/10.1029/2019GL085992, 2020.
Pérez, F. F., Olafsson, J., Ólafsdóttir, S. R., Fontela, M., and Takahashi, T.:
Contrasting drivers and trends of ocean acidification in the subarctic Atlantic, Sci. Rep.-UK, 11, 13991, https://doi.org/10.1038/s41598-021-93324-3, 2021.
Pfeil, B., Olsen, A., Bakker, D. C. E., Hankin, S., Koyuk, H., Kozyr, A., Malczyk, J., Manke, A., Metzl, N., Sabine, C. L., Akl, J., Alin, S. R., Bates, N., Bellerby, R. G. J., Borges, A., Boutin, J., Brown, P. J., Cai, W.-J., Chavez, F. P., Chen, A., Cosca, C., Fassbender, A. J., Feely, R. A., González-Dávila, M., Goyet, C., Hales, B., Hardman-Mountford, N., Heinze, C., Hood, M., Hoppema, M., Hunt, C. W., Hydes, D., Ishii, M., Johannessen, T., Jones, S. D., Key, R. M., Körtzinger, A., Landschützer, P., Lauvset, S. K., Lefèvre, N., Lenton, A., Lourantou, A., Merlivat, L., Midorikawa, T., Mintrop, L., Miyazaki, C., Murata, A., Nakadate, A., Nakano, Y., Nakaoka, S., Nojiri, Y., Omar, A. M., Padin, X. A., Park, G.-H., Paterson, K., Perez, F. F., Pierrot, D., Poisson, A., Ríos, A. F., Santana-Casiano, J. M., Salisbury, J., Sarma, V. V. S. S., Schlitzer, R., Schneider, B., Schuster, U., Sieger, R., Skjelvan, I., Steinhoff, T., Suzuki, T., Takahashi, T., Tedesco, K., Telszewski, M., Thomas, H., Tilbrook, B., Tjiputra, J., Vandemark, D., Veness, T., Wanninkhof, R., Watson, A. J., Weiss, R., Wong, C. S., and Yoshikawa-Inoue, H.:
A uniform, quality controlled Surface Ocean CO2 Atlas (SOCAT), Earth Syst. Sci. Data, 5, 125–143, https://doi.org/10.5194/essd-5-125-2013, 2013.
Planquette, H., Statham, P. J., Fones, G. R., Charette, M. A., Moore, C. M., Salter, I., Nédélec, F. H., Taylor, S. L., French, M., Baker, A. R., Mahowald, N., and Jickells, T. D.:
Dissolved iron in the vicinity of the Crozet Islands, Southern Ocean, Deep-Sea Res. Pt. II, 54, 1999–2019, https://doi.org/10.1016/j.dsr2.2007.06.019, 2007.
Poisson, A. and Chen, C.-T. A.:
Why is there little anthropogenic CO2 in the Antarttic bottom water?, Deep-Sea Res., 34, 1255–1275, https://doi.org/10.1016/0198-0149(87)90075-6, 1987.
Poisson, A., Metzl, N., Brunet, C., Schauer, B., Bres, B., Ruiz-Pino, D., and Louanchi, F.:
Variability of sources and sinks of CO2 in the western Indian and southern oceans during the year 1991, J. Geophys. Res.-Oceans, 98, 22759–22778, https://doi.org/10.1029/93JC02501, 1993.
Pollard, R., Sanders, R., Lucas, M., and Statham, P.:
The Crozet Natural Iron Bloom and Export Experiment (CROZEX), Deep-Sea Res. Pt. II, 54, 1905–1914, https://doi.org/10.1016/j.dsr2.2007.07.023, 2007.
Ritter, R., Landschützer, P., Gruber, N., Fay, A. R., Iida, Y., Jones, S., Nakaoka, S., Park, G.-H., Peylin, P., Rödenbeck, C., Rodgers, K. B., Shutler, J. D., and Zeng, J.:
Observation-Based Trends of the Southern Ocean Carbon Sink, Geophys. Res. Lett., 44, 12,339-12,348, https://doi.org/10.1002/2017GL074837, 2017.
Sabine, C. L., Feely, R. A., Gruber, N., Key, R. M., Lee, K., Bullister, J. L., Wanninkhof, R., Wong, C. S., Wallace, D. W. R., Tilbrook, B., Millero, F. J., Peng, T.-H., Kozyr, A., Ono, T., and Rios, A. F.:
The Oceanic Sink for Anthropogenic CO2, Science, 305, 367–371, https://doi.org/10.1126/science.1097403, 2004.
Sabine, C. L., Feely, R. A., Millero, F. J., Dickson, A. G., Langdon, C., Mecking, S., and Greeley, D.:
Decadal changes in Pacific carbon, J. Geophys. Res.-Oceans, 113, C07021, https://doi.org/10.1029/2007JC004577, 2008.
Sanial, V., van Beek, P., Lansard, B., d'Ovidio, F., Kestenare, E., Souhaut, M., Zhou, M., and Blain, S.:
Study of the phytoplankton plume dynamics off the Crozet Islands (Southern Ocean): A geochemical-physical coupled approach, J. Geophys. Res.-Oceans, 119, 2227–2237, https://doi.org/10.1002/2013JC009305, 2014.
Sasse, T. P., McNeil, B. I., Matear, R. J., and Lenton, A.:
Quantifying the influence of CO2 seasonality on future aragonite undersaturation onset, Biogeosciences, 12, 6017–6031, https://doi.org/10.5194/bg-12-6017-2015, 2015.
Schlitzer, R.:
Ocean Data View, AWI, http://odv.awi.de, last access: 6 January 2021.
Strickland, J. D. H. and Parsons, T. R.:
A Practical Hand Book of Seawater Analysis. Ficheries Research Board of Canada Bulletin, 2nd edn., 310 pp., Ottawa, 1972.
Sutton, A. J., Williams, N. L., and Tilbrook, B.:
Constraining Southern Ocean CO2 Flux Uncertainty Using Uncrewed Surface Vehicle Observations, Geophys. Res. Lett., 48, e2020GL091748, https://doi.org/10.1029/2020GL091748, 2021.
Takahashi, T., Olafsson, J., Goddard, J. G., Chipman, D. W., and Sutherland, S. C.:
Seasonal variation of CO2 and nutrients in the high-latitude surface oceans: A comparative study, Global. Biogeochem. Cy., 7, 843–878, https://doi.org/10.1029/93GB02263, 1993.
Takahashi, T., Sutherland, S. C., Wanninkhof, R., Sweeney, C., Feely, R. A., Chipman, D. W., Hales, B., Friederich, G., Chavez, F., Sabine, C., Watson, A., Bakker, D. C. E., Schuster, U., Metzl, N., Yoshikawa-Inoue, H., Ishii, M., Midorikawa, T., Nojiri, Y., Körtzinger, A., Steinhoff, T., Hoppema, M., Olafsson, J., Arnarson, T. S., Tilbrook, B., Johannessen, T., Olsen, A., Bellerby, R., Wong, C. S., Delille, B., Bates, N. R., and de Baar, H. J. W.:
Climatological mean and decadal change in surface ocean pCO2, and net sea–air CO2 flux over the global oceans, Deep-Sea Res. Pt. II, 56, 554–577, https://doi.org/10.1016/j.dsr2.2008.12.009, 2009.
Takahashi, T., Sweeney, C., Hales, B., Chipman, D., Newberger, T., Goddard, J., Iannuzzi, R., and Sutherland, S.:
The Changing Carbon Cycle in the Southern Ocean, Oceanography, 25, 26–37, https://doi.org/10.5670/oceanog.2012.71, 2012.
Takahashi, T., Sutherland, S. C., Chipman, D. W., Goddard, J. G., Ho, C., Newberger, T., Sweeney, C., and Munro, D. R.:
Climatological distributions of pH, pCO2, total CO2, alkalinity, and CaCO3 saturation in the global surface ocean, and temporal changes at selected locations, Mar. Chem., 164, 95–125, https://doi.org/10.1016/j.marchem.2014.06.004, 2014.
Tanhua, T., Hoppema, M., Jones, E. M., Stöven, T., Hauck, J., Dávila, M. G., Santana-Casiano, M., Álvarez, M., and Strass, V. H.:
Temporal changes in ventilation and the carbonate system in the Atlantic sector of the Southern Ocean, Deep-Sea Res. Pt. II, 138, 26–38, https://doi.org/10.1016/j.dsr2.2016.10.004, 2017.
Terrats, L., Claustre, H., Cornec, M., Mangin, A., and Neukermans, G.:
Detection of Coccolithophore Blooms With BioGeoChemical-Argo Floats, Geophys. Res. Lett., 47, e2020GL090559, https://doi.org/10.1029/2020GL090559, 2020.
Tjiputra, J. F., Olsen, A., Bopp, L., Lenton, A., Pfeil, B., Roy, T., Segschneider, J., Totterdell, I., and Heinze, C.:
Long-term surface pCO2 trends from observations and models, Tellus B, 66, 23083, https://doi.org/10.3402/tellusb.v66.23083, 2014.
Touratier, F. and Goyet, C.:
Applying the new TrOCA approach to assess the distribution of anthropogenic CO2 in the Atlantic Ocean, J. Marine Syst.. 46, 181–197, https://doi.org/10.1016/j.jmarsys.2003.11.020, 2004.
Touratier, F., Azouzi, L., and Goyet, C.:
CFC-11, Δ14C and 3H tracers as a means to assess anthropogenic CO2 concentrations in the ocean, Tellus B, 59, 318–325, https://doi.org/10.1111/j.1600-0889.2006.00247.x, 2007.
Tréguer, P. and Le Corre, P.:
Manuel d'analyse des sels nutritifs dans l'eau de mer (utilisation de l'autoanalyzer II Technicon R), UBO, Brest, France, 109 pp., 1975.
Tyrrell, T., Merico, A., Waniek, J. J., Wong, C. S., Metzl, N., and Whitney, F.:
Effect of seafloor depth on phytoplankton blooms in high-nitrate, low-chlorophyll (HNLC) regions, J. Geophys. Res.-Biogeo., 110, G02007, https://doi.org/10.1029/2005JG000041, 2005.
Uppström, L. R.:
The boron/chlorinity ratio of deep-sea water from the Pacific Ocean, Deep Sea Res. Oceanogr. Abstr., 21, 161–162, https://doi.org/10.1016/0011-7471(74)90074-6, 1974.
van Heuven, S., Pierrot, D., Rae, J. W. B., Lewis, E., and Wallace, D. W. R.:
MATLAB Program Developed for CO2 System Calculations, ORNL/CDIAC-105b, Oak Ridge National Laboratory, Oak Ridge, Tennesee, 2011.
Venables, H. J., Pollard, R. T., and Popova, E. E.:
Physical conditions controlling the development of a regular phytoplankton bloom north of the Crozet Plateau, Southern Ocean, Deep-Sea Res. Pt. II, 54, 1949–1965, https://doi.org/10.1016/j.dsr2.2007.06.014, 2007.
Wanninkhof, R. and Triñanes, J.:
The impact of changing wind speeds on gas transfer and its effect on global air–sea CO2 fluxes, Global. Biogeochem. Cy., 31, 961–974, https://doi.org/10.1002/2016GB005592, 2017.
Weiss, R. F. and Price, B. A.:
Nitrous oxide solubility in water and seawater, Mar. Chem., 8, 347–359, https://doi.org/10.1016/0304-4203(80)90024-9, 1980.
World Meteorological Organization (WMO): The Global Climate Observing System (GCOS), Chairperson, Publications Board, https://gcos.wmo.int/en/global-climate-indicators (last access: 14 September 2020), 2018.
Xue, L., Gao, L., Cai, W.-J., Yu, W., and Wei, M.:
Response of sea surface fugacity of CO2 to the SAM shift south of Tasmania: Regional differences, Geophys. Res. Lett., 42, 3973–3979, https://doi.org/10.1002/2015GL063926, 2015.
Xue, L., Cai, W.-J., Takahashi, T., Gao, L., Wanninkhof, R., Wei, M., Li, K., Feng, L., and Yu, W.:
Climatic modulation of surface acidification rates through summertime wind forcing in the Southern Ocean, Nat. Commun., 9, 3240, https://doi.org/10.1038/s41467-018-05443-7, 2018.
Short summary
Decadal trends of fugacity of CO2 (fCO2), total alkalinity (AT), total carbon (CT) and pH in surface waters are investigated in different domains of the southern Indian Ocean (45°S–57°S) from ongoing and station observations regularly conducted in summer over the period 1998–2019. The fCO2 increase and pH decrease are mainly driven by anthropogenic CO2 estimated just below the summer mixed layer, as well as by a warming south of the polar front or in the fertilized waters near Kerguelen Island.
Decadal trends of fugacity of CO2 (fCO2), total alkalinity (AT), total carbon (CT) and pH in...
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