Articles | Volume 12, issue 18
Biogeosciences, 12, 5547–5562, 2015
https://doi.org/10.5194/bg-12-5547-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Biogeosciences, 12, 5547–5562, 2015
https://doi.org/10.5194/bg-12-5547-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article 30 Sep 2015
Research article | 30 Sep 2015
Can organic matter flux profiles be diagnosed using remineralisation rates derived from observed tracers and modelled ocean transport rates?
J. D. Wilson et al.
Related authors
Katherine A. Crichton, Jamie D. Wilson, Andy Ridgwell, and Paul N. Pearson
Geosci. Model Dev., 14, 125–149, https://doi.org/10.5194/gmd-14-125-2021, https://doi.org/10.5194/gmd-14-125-2021, 2021
Short summary
Short summary
Temperature is a controller of metabolic processes and therefore also a controller of the ocean's biological carbon pump (BCP). We calibrate a temperature-dependent version of the BCP in the cGENIE Earth system model. Since the pre-industrial period, warming has intensified near-surface nutrient recycling, supporting production and largely offsetting stratification-induced surface nutrient limitation. But at the same time less carbon that sinks out of the surface then reaches the deep ocean.
Jamie D. Wilson, Stephen Barker, Neil R. Edwards, Philip B. Holden, and Andy Ridgwell
Biogeosciences, 16, 2923–2936, https://doi.org/10.5194/bg-16-2923-2019, https://doi.org/10.5194/bg-16-2923-2019, 2019
Short summary
Short summary
The remains of plankton rain down from the surface ocean to the deep ocean, acting to store CO2 in the deep ocean. We used a model of biology and ocean circulation to explore the importance of this process in different regions of the ocean. The amount of CO2 stored in the deep ocean is most sensitive to changes in the Southern Ocean. As plankton in the Southern Ocean are likely those most impacted by future climate change, the amount of CO2 they store in the deep ocean could also be affected.
Maria Grigoratou, Fanny M. Monteiro, Daniela N. Schmidt, Jamie D. Wilson, Ben A. Ward, and Andy Ridgwell
Biogeosciences, 16, 1469–1492, https://doi.org/10.5194/bg-16-1469-2019, https://doi.org/10.5194/bg-16-1469-2019, 2019
Short summary
Short summary
The paper presents a novel study based on the traits of shell size, calcification and feeding behaviour of two planktonic foraminifera life stages using modelling simulations. With the model, we tested the cost and benefit of calcification and explored how the interactions of planktonic foraminifera among other plankton groups influence their biomass under different environmental conditions. Our results provide new insights into environmental controls in planktonic foraminifera ecology.
Ben A. Ward, Jamie D. Wilson, Ros M. Death, Fanny M. Monteiro, Andrew Yool, and Andy Ridgwell
Geosci. Model Dev., 11, 4241–4267, https://doi.org/10.5194/gmd-11-4241-2018, https://doi.org/10.5194/gmd-11-4241-2018, 2018
Short summary
Short summary
A novel configuration of an Earth system model includes a diverse plankton community. The model – EcoGEnIE – is sufficiently complex to reproduce a realistic, size-structured plankton community, while at the same time retaining the efficiency to run to a global steady state (~ 10k years). The increased capabilities of EcoGEnIE will allow future exploration of ecological communities on much longer timescales than have so far been examined in global ocean models and particularly for past climate.
Katherine A. Crichton, Andy Ridgwell, Daniel J. Lunt, Alex Farnsworth, and Paul N. Pearson
Clim. Past, 17, 2223–2254, https://doi.org/10.5194/cp-17-2223-2021, https://doi.org/10.5194/cp-17-2223-2021, 2021
Short summary
Short summary
The middle Miocene (15 Ma) was a period of global warmth up to 8 °C warmer than present. We investigate changes in ocean circulation and heat distribution since the middle Miocene and the cooling to the present using the cGENIE Earth system model. We create seven time slices at ~2.5 Myr intervals, constrained with paleo-proxy data, showing a progressive reduction in atmospheric CO2 and a strengthening of the Atlantic Meridional Overturning Circulation.
Yoshiki Kanzaki, Dominik Hülse, Sandra Kirtland Turner, and Andy Ridgwell
Geosci. Model Dev., 14, 5999–6023, https://doi.org/10.5194/gmd-14-5999-2021, https://doi.org/10.5194/gmd-14-5999-2021, 2021
Short summary
Short summary
Sedimentary carbonate plays a central role in regulating Earth’s carbon cycle and climate, and also serves as an archive of paleoenvironments, hosting various trace elements/isotopes. To help obtain
trueenvironmental changes from carbonate records over diagenetic distortion, IMP has been newly developed and has the capability to simulate the diagenesis of multiple carbonate particles and implement different styles of particle mixing by benthos using an adapted transition matrix method.
Jun Shao, Lowell D. Stott, Laurie Menviel, Andy Ridgwell, Malin Ödalen, and Mayhar Mohtadi
Clim. Past, 17, 1507–1521, https://doi.org/10.5194/cp-17-1507-2021, https://doi.org/10.5194/cp-17-1507-2021, 2021
Short summary
Short summary
Planktic and shallow benthic foraminiferal stable carbon isotope
(δ13C) data show a rapid decline during the last deglaciation. This widespread signal was linked to respired carbon released from the deep ocean and its transport through the upper-ocean circulation. Using numerical simulations in which a stronger flux of respired carbon upwells and outcrops in the Southern Ocean, we find that the depleted δ13C signal is transmitted to the rest of the upper ocean through air–sea gas exchange.
Markus Adloff, Andy Ridgwell, Fanny M. Monteiro, Ian J. Parkinson, Alexander J. Dickson, Philip A. E. Pogge von Strandmann, Matthew S. Fantle, and Sarah E. Greene
Geosci. Model Dev., 14, 4187–4223, https://doi.org/10.5194/gmd-14-4187-2021, https://doi.org/10.5194/gmd-14-4187-2021, 2021
Short summary
Short summary
We present the first representation of the trace metals Sr, Os, Li and Ca in a 3D Earth system model (cGENIE). The simulation of marine metal sources (weathering, hydrothermal input) and sinks (deposition) reproduces the observed concentrations and isotopic homogeneity of these metals in the modern ocean. With these new tracers, cGENIE can be used to test hypotheses linking these metal cycles and the cycling of other elements like O and C and simulate their dynamic response to external forcing.
Sebastiaan J. van de Velde, Dominik Hülse, Christopher T. Reinhard, and Andy Ridgwell
Geosci. Model Dev., 14, 2713–2745, https://doi.org/10.5194/gmd-14-2713-2021, https://doi.org/10.5194/gmd-14-2713-2021, 2021
Short summary
Short summary
Biogeochemical interactions between iron and sulfur are central to the long-term biogeochemical evolution of Earth’s oceans. Here, we introduce an iron–sulphur cycle in a model of Earth's oceans. Our analyses show that the results of the model are robust towards parameter choices and that simulated concentrations and reactions are comparable to those observed in ancient ocean analogues (anoxic lakes). Our model represents an important step forward in the study of iron–sulfur cycling.
Katherine A. Crichton, Jamie D. Wilson, Andy Ridgwell, and Paul N. Pearson
Geosci. Model Dev., 14, 125–149, https://doi.org/10.5194/gmd-14-125-2021, https://doi.org/10.5194/gmd-14-125-2021, 2021
Short summary
Short summary
Temperature is a controller of metabolic processes and therefore also a controller of the ocean's biological carbon pump (BCP). We calibrate a temperature-dependent version of the BCP in the cGENIE Earth system model. Since the pre-industrial period, warming has intensified near-surface nutrient recycling, supporting production and largely offsetting stratification-induced surface nutrient limitation. But at the same time less carbon that sinks out of the surface then reaches the deep ocean.
Christopher T. Reinhard, Stephanie L. Olson, Sandra Kirtland Turner, Cecily Pälike, Yoshiki Kanzaki, and Andy Ridgwell
Geosci. Model Dev., 13, 5687–5706, https://doi.org/10.5194/gmd-13-5687-2020, https://doi.org/10.5194/gmd-13-5687-2020, 2020
Short summary
Short summary
We provide documentation and testing of new developments for the oceanic and atmospheric methane cycles in the cGENIE Earth system model. The model is designed to explore Earth's methane cycle across a wide range of timescales and scenarios, in particular assessing the mean climate state and climate perturbations in Earth's deep past. We further document the impact of atmospheric oxygen levels and ocean chemistry on fluxes of methane to the atmosphere from the ocean biosphere.
Malin Ödalen, Jonas Nycander, Andy Ridgwell, Kevin I. C. Oliver, Carlye D. Peterson, and Johan Nilsson
Biogeosciences, 17, 2219–2244, https://doi.org/10.5194/bg-17-2219-2020, https://doi.org/10.5194/bg-17-2219-2020, 2020
Short summary
Short summary
In glacial periods, ocean uptake of carbon is likely a key player for achieving low atmospheric CO2. In climate models, ocean biological uptake of carbon (C) and phosphorus (P) are often assumed to occur in fixed proportions.
In this study, we allow the ratio of C : P to vary and simulate, to first approximation, the complex biological changes that occur in the ocean over long timescales. We show here that, for glacial–interglacial cycles, this complexity contributes to low atmospheric CO2.
Yoshiki Kanzaki, Bernard P. Boudreau, Sandra Kirtland Turner, and Andy Ridgwell
Geosci. Model Dev., 12, 4469–4496, https://doi.org/10.5194/gmd-12-4469-2019, https://doi.org/10.5194/gmd-12-4469-2019, 2019
Short summary
Short summary
This paper provides eLABS, an extension of the lattice-automaton bioturbation simulator LABS. In our new model, the benthic animal behavior interacts and changes dynamically with oxygen and organic matter concentrations and the water flows caused by benthic animals themselves, in a 2-D marine-sediment grid. The model can address the mechanisms behind empirical observations of bioturbation based on the interactions between physical, chemical and biological aspects of marine sediment.
James A. Menking, Edward J. Brook, Sarah A. Shackleton, Jeffrey P. Severinghaus, Michael N. Dyonisius, Vasilii Petrenko, Joseph R. McConnell, Rachael H. Rhodes, Thomas K. Bauska, Daniel Baggenstos, Shaun Marcott, and Stephen Barker
Clim. Past, 15, 1537–1556, https://doi.org/10.5194/cp-15-1537-2019, https://doi.org/10.5194/cp-15-1537-2019, 2019
Short summary
Short summary
An ice core from Taylor Glacier, Antarctica, spans a period ~ 70 000 years ago when Earth entered the last ice age. Chemical analyses of the ice and air bubbles allow for an independent determination of the ages of the ice and gas bubbles. The difference between the age of the ice and the bubbles at any given depth, called ∆age, is unusually high in the Taylor Glacier core compared to the Taylor Dome ice core situated to the south. This implies a dramatic accumulation gradient between the sites.
Jamie D. Wilson, Stephen Barker, Neil R. Edwards, Philip B. Holden, and Andy Ridgwell
Biogeosciences, 16, 2923–2936, https://doi.org/10.5194/bg-16-2923-2019, https://doi.org/10.5194/bg-16-2923-2019, 2019
Short summary
Short summary
The remains of plankton rain down from the surface ocean to the deep ocean, acting to store CO2 in the deep ocean. We used a model of biology and ocean circulation to explore the importance of this process in different regions of the ocean. The amount of CO2 stored in the deep ocean is most sensitive to changes in the Southern Ocean. As plankton in the Southern Ocean are likely those most impacted by future climate change, the amount of CO2 they store in the deep ocean could also be affected.
Krista M. S. Kemppinen, Philip B. Holden, Neil R. Edwards, Andy Ridgwell, and Andrew D. Friend
Clim. Past, 15, 1039–1062, https://doi.org/10.5194/cp-15-1039-2019, https://doi.org/10.5194/cp-15-1039-2019, 2019
Short summary
Short summary
We simulate the Last Glacial Maximum atmospheric CO2 decrease with a large ensemble of parameter sets to investigate the range of possible physical and biogeochemical Earth system changes accompanying the CO2 decrease. Amongst the dominant ensemble changes is an increase in terrestrial carbon, which we attribute to a slower soil respiration rate, and the preservation of carbon by the LGM ice sheets. Further investigation into the role of terrestrial carbon is warranted.
Maria Grigoratou, Fanny M. Monteiro, Daniela N. Schmidt, Jamie D. Wilson, Ben A. Ward, and Andy Ridgwell
Biogeosciences, 16, 1469–1492, https://doi.org/10.5194/bg-16-1469-2019, https://doi.org/10.5194/bg-16-1469-2019, 2019
Short summary
Short summary
The paper presents a novel study based on the traits of shell size, calcification and feeding behaviour of two planktonic foraminifera life stages using modelling simulations. With the model, we tested the cost and benefit of calcification and explored how the interactions of planktonic foraminifera among other plankton groups influence their biomass under different environmental conditions. Our results provide new insights into environmental controls in planktonic foraminifera ecology.
Ben A. Ward, Jamie D. Wilson, Ros M. Death, Fanny M. Monteiro, Andrew Yool, and Andy Ridgwell
Geosci. Model Dev., 11, 4241–4267, https://doi.org/10.5194/gmd-11-4241-2018, https://doi.org/10.5194/gmd-11-4241-2018, 2018
Short summary
Short summary
A novel configuration of an Earth system model includes a diverse plankton community. The model – EcoGEnIE – is sufficiently complex to reproduce a realistic, size-structured plankton community, while at the same time retaining the efficiency to run to a global steady state (~ 10k years). The increased capabilities of EcoGEnIE will allow future exploration of ecological communities on much longer timescales than have so far been examined in global ocean models and particularly for past climate.
Tom Dunkley Jones, Hayley R. Manners, Murray Hoggett, Sandra Kirtland Turner, Thomas Westerhold, Melanie J. Leng, Richard D. Pancost, Andy Ridgwell, Laia Alegret, Rob Duller, and Stephen T. Grimes
Clim. Past, 14, 1035–1049, https://doi.org/10.5194/cp-14-1035-2018, https://doi.org/10.5194/cp-14-1035-2018, 2018
Short summary
Short summary
The Paleocene–Eocene Thermal Maximum (PETM) is a transient global warming event associated with a doubling of atmospheric carbon dioxide concentrations. Here we document a major increase in sediment accumulation rates on a subtropical continental margin during the PETM, likely due to marked changes in hydro-climates and sediment transport. These high sedimentation rates persist through the event and may play a key role in the removal of carbon from the atmosphere by the burial of organic carbon.
Dominik Hülse, Sandra Arndt, Stuart Daines, Pierre Regnier, and Andy Ridgwell
Geosci. Model Dev., 11, 2649–2689, https://doi.org/10.5194/gmd-11-2649-2018, https://doi.org/10.5194/gmd-11-2649-2018, 2018
Short summary
Short summary
We present a 1-D analytical diagenetic model resolving organic matter (OM) cycling and the associated biogeochemical dynamics in marine sediments designed to be coupled to Earth system models (ESMs). The reaction network accounts for the most important reactions associated with OM dynamics. The coupling is described and the OM degradation rate constant is tuned. Various observations, such as pore water profiles, sediment water interface fluxes and OM content, are reproduced with good accuracy.
Malin Ödalen, Jonas Nycander, Kevin I. C. Oliver, Laurent Brodeau, and Andy Ridgwell
Biogeosciences, 15, 1367–1393, https://doi.org/10.5194/bg-15-1367-2018, https://doi.org/10.5194/bg-15-1367-2018, 2018
Short summary
Short summary
We conclude that different initial states for an ocean model result in different capacities for ocean carbon storage due to differences in the ocean circulation state and the origin of the carbon in the initial ocean carbon reservoir. This could explain why it is difficult to achieve comparable responses of the ocean carbon system in model inter-comparison studies in which the initial states vary between models. We show that this effect of the initial state is quantifiable.
Natalie S. Lord, Michel Crucifix, Dan J. Lunt, Mike C. Thorne, Nabila Bounceur, Harry Dowsett, Charlotte L. O'Brien, and Andy Ridgwell
Clim. Past, 13, 1539–1571, https://doi.org/10.5194/cp-13-1539-2017, https://doi.org/10.5194/cp-13-1539-2017, 2017
Short summary
Short summary
We present projections of long-term changes in climate, produced using a statistical emulator based on climate data from a state-of-the-art climate model. We use the emulator to model changes in temperature and precipitation over the late Pliocene (3.3–2.8 million years before present) and the next 200 thousand years. The impact of the Earth's orbit and the atmospheric carbon dioxide concentration on climate is assessed, and the data for the late Pliocene are compared to proxy temperature data.
Taraka Davies-Barnard, Andy Ridgwell, Joy Singarayer, and Paul Valdes
Clim. Past, 13, 1381–1401, https://doi.org/10.5194/cp-13-1381-2017, https://doi.org/10.5194/cp-13-1381-2017, 2017
Short summary
Short summary
We present the first model analysis using a fully coupled dynamic atmosphere–ocean–vegetation GCM over the last 120 kyr that quantifies the net effect of vegetation on climate. This analysis shows that over the whole period the biogeophysical effect (albedo, evapotranspiration) is dominant, and that the biogeochemical impacts may have a lower possible range than typically estimated. This emphasises the temporal reliance of the balance between biogeophysical and biogeochemical effects.
B. A. A. Hoogakker, D. J. R. Thornalley, and S. Barker
Biogeosciences, 13, 211–221, https://doi.org/10.5194/bg-13-211-2016, https://doi.org/10.5194/bg-13-211-2016, 2016
Short summary
Short summary
Models predict a decrease in future ocean O2, driven by surface water warming and freshening in the polar regions, causing a reduction in ocean circulation. Here we assess this effect in the past, focussing on the response of deep and intermediate waters from the North Atlantic during large-scale ice rafting and millennial-scale cooling events of the last glacial.
Our assessment agrees with the models but also highlights the importance of biological processes driving ocean O2 change.
N. S. Jones, A. Ridgwell, and E. J. Hendy
Biogeosciences, 12, 1339–1356, https://doi.org/10.5194/bg-12-1339-2015, https://doi.org/10.5194/bg-12-1339-2015, 2015
Short summary
Short summary
Production of calcium carbonate by coral reefs is important in the global carbon cycle. Using a global framework we evaluate four models of reef calcification against observed values. The temperature-only model showed significant skill in reproducing coral calcification rates. The absence of any predictive power for whole reef systems highlights the importance of coral cover and the need for an ecosystem modelling approach accounting for population dynamics in terms of mortality and recruitment.
R. Death, J. L. Wadham, F. Monteiro, A. M. Le Brocq, M. Tranter, A. Ridgwell, S. Dutkiewicz, and R. Raiswell
Biogeosciences, 11, 2635–2643, https://doi.org/10.5194/bg-11-2635-2014, https://doi.org/10.5194/bg-11-2635-2014, 2014
G. Colbourn, A. Ridgwell, and T. M. Lenton
Geosci. Model Dev., 6, 1543–1573, https://doi.org/10.5194/gmd-6-1543-2013, https://doi.org/10.5194/gmd-6-1543-2013, 2013
M. Eby, A. J. Weaver, K. Alexander, K. Zickfeld, A. Abe-Ouchi, A. A. Cimatoribus, E. Crespin, S. S. Drijfhout, N. R. Edwards, A. V. Eliseev, G. Feulner, T. Fichefet, C. E. Forest, H. Goosse, P. B. Holden, F. Joos, M. Kawamiya, D. Kicklighter, H. Kienert, K. Matsumoto, I. I. Mokhov, E. Monier, S. M. Olsen, J. O. P. Pedersen, M. Perrette, G. Philippon-Berthier, A. Ridgwell, A. Schlosser, T. Schneider von Deimling, G. Shaffer, R. S. Smith, R. Spahni, A. P. Sokolov, M. Steinacher, K. Tachiiri, K. Tokos, M. Yoshimori, N. Zeng, and F. Zhao
Clim. Past, 9, 1111–1140, https://doi.org/10.5194/cp-9-1111-2013, https://doi.org/10.5194/cp-9-1111-2013, 2013
P. B. Holden, N. R. Edwards, S. A. Müller, K. I. C. Oliver, R. M. Death, and A. Ridgwell
Biogeosciences, 10, 1815–1833, https://doi.org/10.5194/bg-10-1815-2013, https://doi.org/10.5194/bg-10-1815-2013, 2013
Related subject area
Biogeochemistry: Open 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
Deep chlorophyll maximum and nutricline in the Mediterranean Sea: emerging properties from a multi-platform assimilated biogeochemical model experiment
Phosphorus cycling in the upper waters of the Mediterranean Sea (PEACETIME cruise): relative contribution of external and internal sources
Fast local warming is the main driver of recent deoxygenation in the northern Arabian Sea
Influence of atmospheric deposition on biogeochemical cycles in an oligotrophic ocean system
Impact of dust addition on the metabolism of Mediterranean plankton communities and carbon export under present and future conditions of pH and temperature
Comparing CLE-AdCSV applications using SA and TAC to determine the Fe-binding characteristics of model ligands in seawater
Impact of dust addition on Mediterranean plankton communities under present and future conditions of pH and temperature: an experimental overview
Reviews and syntheses: Trends in primary production in the Bay of Bengal – is it at a tipping point?
Incorporating the stable carbon isotope 13C in the ocean biogeochemical component of the Max Planck Institute Earth System Model
Seasonal cycling of zinc and cobalt in the south-eastern Atlantic along the GEOTRACES GA10 section
Carbon export and fate beneath a dynamic upwelled filament off the California coast
Contrasted release of insoluble elements (Fe, Al, rare earth elements, Th, Pa) after dust deposition in seawater: a tank experiment approach
On the barium–oxygen consumption relationship in the Mediterranean Sea: implications for mesopelagic marine snow remineralization
Compound high-temperature and low-chlorophyll extremes in the ocean over the satellite period
Can machine learning extract the mechanisms controlling phytoplankton growth from large-scale observations? – A proof-of-concept study
Reviews and syntheses: The biogeochemical cycle of silicon in the modern ocean
Oxygen budget of the north-western Mediterranean deep- convection region
Cross-basin differences in the nutrient assimilation characteristics of induced phytoplankton blooms in the subtropical Pacific waters
Dynamics of the deep chlorophyll maximum in the Black Sea as depicted by BGC-Argo floats
Nitrate assimilation and regeneration in the Barents Sea: insights from nitrate isotopes
Assimilating synthetic Biogeochemical-Argo and ocean colour observations into a global ocean model to inform observing system design
Southern Ocean Biogeochemical Argo detect under-ice phytoplankton growth before sea ice retreat
A new intermittent regime of convective ventilation threatens the Black Sea oxygenation status
Reviews and syntheses: Present, past, and future of the oxygen minimum zone in the northern Indian Ocean
Particulate rare earth element behavior in the North Atlantic (GEOVIDE cruise)
Elevated sources of cobalt in the Arctic Ocean
Increase in ocean acidity variability and extremes under increasing atmospheric CO2
Can ocean community production and respiration be determined by measuring high-frequency oxygen profiles from autonomous floats?
Assessing the value of biogeochemical Argo profiles versus ocean color observations for biogeochemical model optimization in the Gulf of Mexico
The Southern Annular Mode (SAM) influences phytoplankton communities in the seasonal ice zone of the Southern Ocean
Profiling float observation of thermohaline staircases in the western Mediterranean Sea and impact on nutrient fluxes
Ocean carbonate system variability in the North Atlantic Subpolar surface water (1993–2017)
Characterizing the surface microlayer in the Mediterranean Sea: trace metal concentrations and microbial plankton abundance
Spatial variations in silicate-to-nitrate ratios in Southern Ocean surface waters are controlled in the short term by physics rather than biology
Phytoplankton and dimethylsulfide dynamics at two contrasting Arctic ice edges
Experiment design and bacterial abundance control extracellular H2O2 concentrations during four series of mesocosm experiments
Dissolved iron in the North Atlantic Ocean and Labrador Sea along the GEOVIDE section (GEOTRACES section GA01)
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Anna Teruzzi, Giorgio Bolzon, Laura Feudale, and Gianpiero Cossarini
Biogeosciences, 18, 6147–6166, https://doi.org/10.5194/bg-18-6147-2021, https://doi.org/10.5194/bg-18-6147-2021, 2021
Short summary
Short summary
During summer, maxima of phytoplankton chlorophyll concentration (DCM) occur in the subsurface of the Mediterranean Sea and can play a relevant role in carbon sequestration into the ocean interior. A numerical model based on in situ and satellite observations provides insights into the range of DCM conditions across the relatively small Mediterranean Sea and shows a western DCM that is 25 % shallower and with a higher phytoplankton chlorophyll concentration than in the eastern Mediterranean.
Elvira Pulido-Villena, Karine Desboeufs, Kahina Djaoudi, France Van Wambeke, Stéphanie Barrillon, Andrea Doglioli, Anne Petrenko, Vincent Taillandier, Franck Fu, Tiphanie Gaillard, Sophie Guasco, Sandra Nunige, Sylvain Triquet, and Cécile Guieu
Biogeosciences, 18, 5871–5889, https://doi.org/10.5194/bg-18-5871-2021, https://doi.org/10.5194/bg-18-5871-2021, 2021
Short summary
Short summary
We report on phosphorus dynamics in the surface layer of the Mediterranean Sea. Highly sensitive phosphate measurements revealed vertical gradients above the phosphacline. The relative contribution of diapycnal fluxes to total external supply of phosphate to the mixed layer decreased towards the east, where atmospheric deposition dominated. Taken together, external sources of phosphate contributed little to total supply, which was mainly sustained by enzymatic hydrolysis of organic phosphorus.
Zouhair Lachkar, Michael Mehari, Muchamad Al Azhar, Marina Lévy, and Shafer Smith
Biogeosciences, 18, 5831–5849, https://doi.org/10.5194/bg-18-5831-2021, https://doi.org/10.5194/bg-18-5831-2021, 2021
Short summary
Short summary
This study documents and quantifies a significant recent oxygen decline in the upper layers of the Arabian Sea and explores its drivers. Using a modeling approach we show that the fast local warming of sea surface is the main factor causing this oxygen drop. Concomitant summer monsoon intensification contributes to this trend, although to a lesser extent. These changes exacerbate oxygen depletion in the subsurface, threatening marine habitats and altering the local biogeochemistry.
France Van Wambeke, Vincent Taillandier, Karine Desboeufs, Elvira Pulido-Villena, Julie Dinasquet, Anja Engel, Emilio Marañón, Céline Ridame, and Cécile Guieu
Biogeosciences, 18, 5699–5717, https://doi.org/10.5194/bg-18-5699-2021, https://doi.org/10.5194/bg-18-5699-2021, 2021
Short summary
Short summary
Simultaneous in situ measurements of (dry and wet) atmospheric deposition and biogeochemical stocks and fluxes in the sunlit waters of the open Mediterranean Sea revealed complex physical and biological processes occurring within the mixed layer. Nitrogen (N) budgets were computed to compare the sources and sinks of N in the mixed layer. The transitory effect observed after a wet dust deposition impacted the microbial food web down to the deep chlorophyll maximum.
Frédéric Gazeau, France Van Wambeke, Emilio Marañón, Maria Pérez-Lorenzo, Samir Alliouane, Christian Stolpe, Thierry Blasco, Nathalie Leblond, Birthe Zäncker, Anja Engel, Barbara Marie, Julie Dinasquet, and Cécile Guieu
Biogeosciences, 18, 5423–5446, https://doi.org/10.5194/bg-18-5423-2021, https://doi.org/10.5194/bg-18-5423-2021, 2021
Short summary
Short summary
Our study shows that the impact of dust deposition on primary production depends on the initial composition and metabolic state of the tested community and is constrained by the amount of nutrients added, to sustain both the fast response of heterotrophic prokaryotes and the delayed one of phytoplankton. Under future environmental conditions, heterotrophic metabolism will be more impacted than primary production, therefore reducing the capacity of surface waters to sequester anthropogenic CO2.
Loes J. A. Gerringa, Martha Gledhill, Indah Ardiningsih, Niels Muntjewerf, and Luis M. Laglera
Biogeosciences, 18, 5265–5289, https://doi.org/10.5194/bg-18-5265-2021, https://doi.org/10.5194/bg-18-5265-2021, 2021
Short summary
Short summary
For 3 decades, competitive ligand exchange–adsorptive cathodic stripping voltammetry was used to estimate the Fe-binding capacity of organic matter in seawater. In this paper the performance of the competing ligands is compared through the analysis of a series of model ligands.
The main finding of this paper is that the determined speciation parameters are not independent of the application, making interpretation of Fe speciation data more complex than it was thought before.
Frédéric Gazeau, Céline Ridame, France Van Wambeke, Samir Alliouane, Christian Stolpe, Jean-Olivier Irisson, Sophie Marro, Jean-Michel Grisoni, Guillaume De Liège, Sandra Nunige, Kahina Djaoudi, Elvira Pulido-Villena, Julie Dinasquet, Ingrid Obernosterer, Philippe Catala, and Cécile Guieu
Biogeosciences, 18, 5011–5034, https://doi.org/10.5194/bg-18-5011-2021, https://doi.org/10.5194/bg-18-5011-2021, 2021
Short summary
Short summary
This paper shows that the impacts of Saharan dust deposition in different Mediterranean basins are as strong as those observed in coastal waters but differed substantially between the three tested stations, differences attributed to variable initial metabolic states. A stronger impact of warming and acidification on mineralization suggests a decreased capacity of Mediterranean surface communities to sequester CO2 following the deposition of atmospheric particles in the coming decades.
Carolin R. Löscher
Biogeosciences, 18, 4953–4963, https://doi.org/10.5194/bg-18-4953-2021, https://doi.org/10.5194/bg-18-4953-2021, 2021
Short summary
Short summary
The Bay of Bengal (BoB) is classically seen as an ocean region with low primary production, which has been predicted to decrease even further. Here, the importance of such a trend is used to explore what could happen to the BoB's low-oxygen core waters if primary production decreases. Lower biological production leads to less oxygen loss in deeper waters by respiration; thus it could be that oxygen will not further decrease and the BoB will not become anoxic, different to other low-oxygen areas.
Bo Liu, Katharina D. Six, and Tatiana Ilyina
Biogeosciences, 18, 4389–4429, https://doi.org/10.5194/bg-18-4389-2021, https://doi.org/10.5194/bg-18-4389-2021, 2021
Short summary
Short summary
We incorporate a new representation of the stable carbon isotope 13C in a global ocean biogeochemistry model. The model well reproduces the present-day 13C observations. We find a recent observation-based estimate of the oceanic 13C Suess effect (the decrease in 13C/12C ratio due to uptake of anthropogenic CO2; 13CSE) possibly underestimates 13CSE by 0.1–0.26 per mil. The new model will aid in better understanding the past ocean state via comparison to 13C/12C measurements from sediment cores.
Neil J. Wyatt, Angela Milne, Eric P. Achterberg, Thomas J. Browning, Heather A. Bouman, E. Malcolm S. Woodward, and Maeve C. Lohan
Biogeosciences, 18, 4265–4280, https://doi.org/10.5194/bg-18-4265-2021, https://doi.org/10.5194/bg-18-4265-2021, 2021
Short summary
Short summary
Using data collected during two expeditions to the South Atlantic Ocean, we investigated how the interaction between external sources and biological activity influenced the availability of the trace metals zinc and cobalt. This is important as both metals play essential roles in the metabolism and growth of phytoplankton and thus influence primary productivity of the oceans. We found seasonal changes in both processes that helped explain upper-ocean trace metal cycling.
Hannah L. Bourne, James K. B. Bishop, Elizabeth J. Connors, and Todd J. Wood
Biogeosciences, 18, 3053–3086, https://doi.org/10.5194/bg-18-3053-2021, https://doi.org/10.5194/bg-18-3053-2021, 2021
Short summary
Short summary
To learn how the biological carbon pump works in productive coastal upwelling systems, four autonomous carbon flux explorers measured carbon flux through the twilight zone beneath an offshore-flowing filament of biologically productive water. Strikingly different particle classes dominated the carbon fluxes during successive stages of the filament evolution over 30 d. Both flux and transfer efficiency were far greater than expected, suggesting an outsized filament impact in California waters.
Matthieu Roy-Barman, Lorna Foliot, Eric Douville, Nathalie Leblond, Fréderic Gazeau, Matthieu Bressac, Thibaut Wagener, Céline Ridame, Karine Desboeufs, and Cécile Guieu
Biogeosciences, 18, 2663–2678, https://doi.org/10.5194/bg-18-2663-2021, https://doi.org/10.5194/bg-18-2663-2021, 2021
Short summary
Short summary
The release of insoluble elements such as aluminum (Al), iron (Fe), rare earth elements (REEs), thorium (Th) and protactinium (Pa) when Saharan dust falls over the Mediterranean Sea was studied during tank experiments under present and future climate conditions. Each element exhibited different dissolution kinetics and dissolution fractions (always lower than a few percent). Changes in temperature and/or pH under greenhouse conditions lead to a lower Th release and a higher light REE release.
Stéphanie H. M. Jacquet, Dominique Lefèvre, Christian Tamburini, Marc Garel, Frédéric A. C. Le Moigne, Nagib Bhairy, and Sophie Guasco
Biogeosciences, 18, 2205–2212, https://doi.org/10.5194/bg-18-2205-2021, https://doi.org/10.5194/bg-18-2205-2021, 2021
Short summary
Short summary
We present new data concerning the relation between biogenic barium (Baxs, a tracer of carbon remineralization at mesopelagic depths), O2 consumption and prokaryotic heterotrophic production (PHP) in the Mediterranean Sea. The purpose of this paper is to improve our understanding of the relation between Baxs, PHP and O2 and to test the validity of the Dehairs transfer function in the Mediterranean Sea. This relation has never been tested in the Mediterranean Sea.
Natacha Le Grix, Jakob Zscheischler, Charlotte Laufkötter, Cecile S. Rousseaux, and Thomas L. Frölicher
Biogeosciences, 18, 2119–2137, https://doi.org/10.5194/bg-18-2119-2021, https://doi.org/10.5194/bg-18-2119-2021, 2021
Short summary
Short summary
Marine ecosystems could suffer severe damage from the co-occurrence of a marine heat wave with extremely low chlorophyll concentration. Here, we provide a first assessment of compound marine heat wave and
low-chlorophyll events in the global ocean from 1998 to 2018. We reveal hotspots of these compound events in the equatorial Pacific and in the Arabian Sea and show that they mostly occur in summer at high latitudes and their frequency is modulated by large-scale modes of climate variability.
Christopher Holder and Anand Gnanadesikan
Biogeosciences, 18, 1941–1970, https://doi.org/10.5194/bg-18-1941-2021, https://doi.org/10.5194/bg-18-1941-2021, 2021
Short summary
Short summary
A challenge for marine ecologists in studying phytoplankton is linking small-scale relationships found in a lab to broader relationships observed on large scales in the environment. We investigated whether machine learning (ML) could help connect these small- and large-scale relationships. ML was able to provide qualitative information about the small-scale processes from large-scale information. This method could help identify important relationships from observations in future research.
Paul J. Tréguer, Jill N. Sutton, Mark Brzezinski, Matthew A. Charette, Timothy Devries, Stephanie Dutkiewicz, Claudia Ehlert, Jon Hawkings, Aude Leynaert, Su Mei Liu, Natalia Llopis Monferrer, María López-Acosta, Manuel Maldonado, Shaily Rahman, Lihua Ran, and Olivier Rouxel
Biogeosciences, 18, 1269–1289, https://doi.org/10.5194/bg-18-1269-2021, https://doi.org/10.5194/bg-18-1269-2021, 2021
Short summary
Short summary
Silicon is the second most abundant element of the Earth's crust. In this review, we show that silicon inputs and outputs, to and from the world ocean, are 57 % and 37 % higher, respectively, than previous estimates. These changes are significant, modifying factors such as the geochemical residence time of silicon, which is now about 8000 years and 2 times faster than previously assumed. We also update the total biogenic silica pelagic production and provide an estimate for sponge production.
Caroline Ulses, Claude Estournel, Marine Fourrier, Laurent Coppola, Fayçal Kessouri, Dominique Lefèvre, and Patrick Marsaleix
Biogeosciences, 18, 937–960, https://doi.org/10.5194/bg-18-937-2021, https://doi.org/10.5194/bg-18-937-2021, 2021
Short summary
Short summary
We analyse the seasonal cycle of O2 and estimate an annual O2 budget in the north-western Mediterranean deep-convection region, using a numerical model. We show that this region acts as a large sink of atmospheric O2 and as a major source of O2 for the western Mediterranean Sea. The decrease in the deep convection intensity predicted in recent projections may have important consequences on the overall uptake of O2 in the Mediterranean Sea and on the O2 exchanges with the Atlantic Ocean.
Fuminori Hashihama, Hiroaki Saito, Taketoshi Kodama, Saori Yasui-Tamura, Jota Kanda, Iwao Tanita, Hiroshi Ogawa, E. Malcolm S. Woodward, Philip W. Boyd, and Ken Furuya
Biogeosciences, 18, 897–915, https://doi.org/10.5194/bg-18-897-2021, https://doi.org/10.5194/bg-18-897-2021, 2021
Short summary
Short summary
We investigated the nutrient assimilation characteristics of deep-water-induced phytoplankton blooms across the subtropical North and South Pacific Ocean. Nutrient drawdown ratios of dissolved inorganic nitrogen to phosphate were anomalously low in the western North Pacific, likely due to the high phosphate uptake capability of low-phosphate-adapted phytoplankton. The anomalous phosphate uptake might influence the maintenance of chronic phosphate depletion in the western North Pacific.
Florian Ricour, Arthur Capet, Fabrizio D'Ortenzio, Bruno Delille, and Marilaure Grégoire
Biogeosciences, 18, 755–774, https://doi.org/10.5194/bg-18-755-2021, https://doi.org/10.5194/bg-18-755-2021, 2021
Short summary
Short summary
This paper addresses the phenology of the deep chlorophyll maximum (DCM) in the Black Sea (BS). We show that the DCM forms in March at a density level set by the winter mixed layer. It maintains this location until June, suggesting an influence of the DCM on light and nutrient profiles rather than mere adaptation to external factors. In summer, the DCM concentrates ~55 % of the chlorophyll in a 10 m layer at ~35 m depth and should be considered a major feature of the BS phytoplankton dynamics.
Robyn E. Tuerena, Joanne Hopkins, Raja S. Ganeshram, Louisa Norman, Camille de la Vega, Rachel Jeffreys, and Claire Mahaffey
Biogeosciences, 18, 637–653, https://doi.org/10.5194/bg-18-637-2021, https://doi.org/10.5194/bg-18-637-2021, 2021
Short summary
Short summary
The Barents Sea is a rapidly changing shallow sea within the Arctic. Here, nitrate, an essential nutrient, is fully consumed by algae in surface waters during summer months. Nitrate is efficiently regenerated in the Barents Sea, and there is no evidence for nitrogen loss from the sediments by denitrification, which is prevalent on other Arctic shelves. This suggests that nitrogen availability in the Barents Sea is largely determined by the supply of nutrients in water masses from the Atlantic.
David Ford
Biogeosciences, 18, 509–534, https://doi.org/10.5194/bg-18-509-2021, https://doi.org/10.5194/bg-18-509-2021, 2021
Short summary
Short summary
Biogeochemical-Argo floats are starting to routinely measure ocean chlorophyll, nutrients, oxygen, and pH. This study generated synthetic observations representing two potential Biogeochemical-Argo observing system designs and created a data assimilation scheme to combine them with an ocean model. The proposed system of 1000 floats brought clear benefits to model results, with additional floats giving further benefit. Existing satellite ocean colour observations gave complementary information.
Mark Hague and Marcello Vichi
Biogeosciences, 18, 25–38, https://doi.org/10.5194/bg-18-25-2021, https://doi.org/10.5194/bg-18-25-2021, 2021
Short summary
Short summary
This paper examines the question of what causes the rapid spring growth of microscopic marine algae (phytoplankton) in the ice-covered ocean surrounding Antarctica. One prominent hypothesis proposes that the melting of sea ice is the primary cause, while our results suggest that this is only part of the explanation. In particular, we show that phytoplankton are able to start growing before the sea ice melts appreciably, much earlier than previously thought.
Arthur Capet, Luc Vandenbulcke, and Marilaure Grégoire
Biogeosciences, 17, 6507–6525, https://doi.org/10.5194/bg-17-6507-2020, https://doi.org/10.5194/bg-17-6507-2020, 2020
Short summary
Short summary
The Black Sea is 2000 m deep, but, due to limited ventilation, only about the upper 100 m contains enough oxygen to support marine life such as fish. This oxygenation depth has been shown to be decreasing (1955–2019). Here, we evidence that atmospheric warming induced a clear shift in an important ventilation mechanism. We highlight the impact of this shift on oxygenation. There are important implications for marine life and carbon and nutrient cycling if this new ventilation regime persists.
Tim Rixen, Greg Cowie, Birgit Gaye, Joaquim Goes, Helga do Rosário Gomes, Raleigh R. Hood, Zouhair Lachkar, Henrike Schmidt, Joachim Segschneider, and Arvind Singh
Biogeosciences, 17, 6051–6080, https://doi.org/10.5194/bg-17-6051-2020, https://doi.org/10.5194/bg-17-6051-2020, 2020
Short summary
Short summary
The northern Indian Ocean hosts an extensive oxygen minimum zone (OMZ), which intensified due to human-induced global changes. This includes the occurrence of anoxic events on the Indian shelf and affects benthic ecosystems and the pelagic ecosystem structure in the Arabian Sea. Consequences for biogeochemical cycles are unknown, which, in addition to the poor representation of mesoscale features, reduces the reliability of predictions of the future OMZ development in the northern Indian Ocean.
Marion Lagarde, Nolwenn Lemaitre, Hélène Planquette, Mélanie Grenier, Moustafa Belhadj, Pascale Lherminier, and Catherine Jeandel
Biogeosciences, 17, 5539–5561, https://doi.org/10.5194/bg-17-5539-2020, https://doi.org/10.5194/bg-17-5539-2020, 2020
Randelle M. Bundy, Alessandro Tagliabue, Nicholas J. Hawco, Peter L. Morton, Benjamin S. Twining, Mariko Hatta, Abigail E. Noble, Mattias R. Cape, Seth G. John, Jay T. Cullen, and Mak A. Saito
Biogeosciences, 17, 4745–4767, https://doi.org/10.5194/bg-17-4745-2020, https://doi.org/10.5194/bg-17-4745-2020, 2020
Short summary
Short summary
Cobalt (Co) is an essential nutrient for ocean microbes and is scarce in most areas of the ocean. This study measured Co concentrations in the Arctic Ocean for the first time and found that Co levels are extremely high in the surface waters of the Canadian Arctic. Although the Co primarily originates from the shelf, the high concentrations persist throughout the central Arctic. Co in the Arctic appears to be increasing over time and might be a source of Co to the North Atlantic.
Friedrich A. Burger, Jasmin G. John, and Thomas L. Frölicher
Biogeosciences, 17, 4633–4662, https://doi.org/10.5194/bg-17-4633-2020, https://doi.org/10.5194/bg-17-4633-2020, 2020
Short summary
Short summary
Ensemble simulations of an Earth system model reveal that ocean acidity extremes have increased in the past few decades and are projected to increase further in terms of frequency, intensity, duration, and volume extent. The increase is not only caused by the long-term ocean acidification due to the uptake of anthropogenic CO2, but also due to changes in short-term variability. The increase in ocean acidity extremes may enhance the risk of detrimental impacts on marine organisms.
Christopher Gordon, Katja Fennel, Clark Richards, Lynn K. Shay, and Jodi K. Brewster
Biogeosciences, 17, 4119–4134, https://doi.org/10.5194/bg-17-4119-2020, https://doi.org/10.5194/bg-17-4119-2020, 2020
Short summary
Short summary
We describe a method for correcting errors in oxygen optode measurements on autonomous platforms in the ocean. The errors result from the relatively slow response time of the sensor. The correction method includes an in situ determination of the effective response time and requires the time stamps of the individual measurements. It is highly relevant for the BGC-Argo program and also applicable to gliders. We also explore if diurnal changes in oxygen can be obtained from profiling floats.
Bin Wang, Katja Fennel, Liuqian Yu, and Christopher Gordon
Biogeosciences, 17, 4059–4074, https://doi.org/10.5194/bg-17-4059-2020, https://doi.org/10.5194/bg-17-4059-2020, 2020
Short summary
Short summary
We assess trade-offs between different types of biological observations, specifically satellite ocean color and BGC-Argo profiles and the benefits of combining both for optimizing a biogeochemical model of the Gulf of Mexico. Using all available observations leads to significant improvements in observed and unobserved variables (including primary production and C export). Our results highlight the significant benefits of BGC-Argo measurements for biogeochemical model optimization and validation.
Bruce L. Greaves, Andrew T. Davidson, Alexander D. Fraser, John P. McKinlay, Andrew Martin, Andrew McMinn, and Simon W. Wright
Biogeosciences, 17, 3815–3835, https://doi.org/10.5194/bg-17-3815-2020, https://doi.org/10.5194/bg-17-3815-2020, 2020
Short summary
Short summary
We observed that variation in the Southern Annular Mode (SAM) over 11 years showed a relationship with the species composition of hard-shelled phytoplankton in the seasonal ice zone (SIZ) of the Southern Ocean. Phytoplankton in the SIZ are productive during the southern spring and summer when the area is ice-free, with production feeding most Antarctic life. The SAM is known to be increasing with climate change, and changes in phytoplankton in the SIZ may have implications for higher life forms.
Vincent Taillandier, Louis Prieur, Fabrizio D'Ortenzio, Maurizio Ribera d'Alcalà, and Elvira Pulido-Villena
Biogeosciences, 17, 3343–3366, https://doi.org/10.5194/bg-17-3343-2020, https://doi.org/10.5194/bg-17-3343-2020, 2020
Short summary
Short summary
This study addresses the role played by vertical diffusion in the nutrient enrichment of the Levantine intermediate waters, a process particularly relevant inside thermohaline staircases. Thanks to a high profiling frequency over a 4-year period, BGC-Argo float observations reveal the temporal continuity of the layering patterns encountered during the cruise PEACETIME and their impact on vertical and lateral transfers of nitrate between the deep reservoir and the surface productive zone.
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
Short summary
Short summary
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.
Antonio Tovar-Sánchez, Araceli Rodríguez-Romero, Anja Engel, Birthe Zäncker, Franck Fu, Emilio Marañón, María Pérez-Lorenzo, Matthieu Bressac, Thibaut Wagener, Sylvain Triquet, Guillaume Siour, Karine Desboeufs, and Cécile Guieu
Biogeosciences, 17, 2349–2364, https://doi.org/10.5194/bg-17-2349-2020, https://doi.org/10.5194/bg-17-2349-2020, 2020
Short summary
Short summary
Residence times of particulate metals derived from aerosol deposition in the Sea Surface Microlayer of the Mediterranean Sea ranged from a couple of minutes (e.g., for Fe) to a few hours (e.g., for Cu). Microbial activity seems to play an important role in in this process and in the concentration and distribution of metals between diferent water layers.
Pieter Demuynck, Toby Tyrrell, Alberto Naveira Garabato, Mark Christopher Moore, and Adrian Peter Martin
Biogeosciences, 17, 2289–2314, https://doi.org/10.5194/bg-17-2289-2020, https://doi.org/10.5194/bg-17-2289-2020, 2020
Short summary
Short summary
The availability of macronutrients N and Si is of key importance to sustain life in the Southern Ocean. N and Si are available in abundance at the southern boundary of the Southern Ocean due to constant supply from the deep ocean. In the more northern regions of the Southern Ocean, a decline in macronutrient concentration is noticed, especially strong for Si rather than N. This paper uses a simplified biogeochemical model to investigate processes responsible for this decline in concentration.
Martine Lizotte, Maurice Levasseur, Virginie Galindo, Margaux Gourdal, Michel Gosselin, Jean-Éric Tremblay, Marjolaine Blais, Joannie Charette, and Rachel Hussherr
Biogeosciences, 17, 1557–1581, https://doi.org/10.5194/bg-17-1557-2020, https://doi.org/10.5194/bg-17-1557-2020, 2020
Short summary
Short summary
This study brings further support to the premise that the prevalence of younger and thinner icescapes over older and thicker ones in the Canadian High Arctic favors the early development of under-ice microorganisms as well as their production of the climate-relevant gas dimethylsulfide (DMS). Given the rapid rate of climate-driven changes in Arctic sea ice, our results suggest implications for the timing and magnitude of DMS pulses in the Arctic, with ramifications for climate forecasting.
Mark J. Hopwood, Nicolas Sanchez, Despo Polyviou, Øystein Leiknes, Julián Alberto Gallego-Urrea, Eric P. Achterberg, Murat V. Ardelan, Javier Aristegui, Lennart Bach, Sengul Besiktepe, Yohann Heriot, Ioanna Kalantzi, Tuba Terbıyık Kurt, Ioulia Santi, Tatiana M. Tsagaraki, and David Turner
Biogeosciences, 17, 1309–1326, https://doi.org/10.5194/bg-17-1309-2020, https://doi.org/10.5194/bg-17-1309-2020, 2020
Short summary
Short summary
Hydrogen peroxide, H2O2, is formed naturally in sunlight-exposed water by photochemistry. At high concentrations it is undesirable to biological cells because it is a stressor. Here, across a range of incubation experiments in diverse marine environments (Gran Canaria, the Mediterranean, Patagonia and Svalbard), we determine that two factors consistently affect the H2O2 concentrations irrespective of geographical location: bacteria abundance and experiment design.
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
Biogeosciences, 17, 917–943, https://doi.org/10.5194/bg-17-917-2020, https://doi.org/10.5194/bg-17-917-2020, 2020
Short summary
Short summary
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.
Cited articles
Anderson, L. A. and Sarmiento, J. L.: Redfield ratios of remineralization determined by nutrient data analysis, Global Biogeochem. Cy., 8, 65–80, https://doi.org/10.1029/93GB03318, 1994.
Annan, J., Hargreaves, J., Edwards, N., and Marsh, R.: Parameter estimation in an intermediate complexity earth system model using an ensemble Kalman filter, Ocean Model., 8, 135–154, https://doi.org/10.1016/j.ocemod.2003.12.004, 2005.
Archer, D. and Maier-Reimer, E.: Effect of deep-sea sedimentary calcite preservation on atmospheric CO2 concentration, Nature, 367, 260–263, https://doi.org/10.1038/367260a0, 1994.
Armstrong, R. A., Lee, C., Hedges, J. I., Honjo, S., and Wakeham, S. G.: A new, mechanistic model for organic carbon fluxes in the ocean based on the quantitative association of POC with ballast minerals, Deep-Sea Res. Pt. II, 49, 219–236, 2002.
Bacastow, R. and Maier-Reimer, E.: Dissolved organic carbon in modelling new production, Global Biogeochem. Cy., 5, 71–85, 1991.
Berelson, W.: The flux of particulate organic carbon into the ocean interior: a comparison of four U.S. JGOFS regoinal studies, Oceanography, 14, 59–67, 2001.
Broecker, W. S., Peacock, S. L., Walker, S., Weiss, R., Fahrbach, E., Schroeder, M., Mikolajewicz, U., Heinze, C., Key, R., Peng, T.-H., and Rubin, S.: How much deep water is formed in the Southern Ocean?, J. Geophys. Res.-Oceans, 103, 15833–15843, https://doi.org/10.1029/98JC00248, 1998.
Buesseler, K. O., Antia, A. N., Chen, M., Fowler, S. W., Gardner, W. D., Gustafsson, O., Harada, K., Michaels, A .F., Rutgers v. d. Loeff, M., Sarin, M., Steinberg, D. K., and Trull, T.: An assessment of the use of sediment traps for estimating upper ocean particle fluxes, J. Marine Res., 3, 345–416, 2007.
Deutsch, C., Sarmiento, J. L., Sigman, D. M., Gruber, N., and Dunne, J. P.: Spatial coupling of nitrogen inputs and losses in the ocean, Nature, 445, 163–167, https://doi.org/10.1038/nature05392, 2007.
Dietze, H. and Oschlies, A.: Modeling abiotic production of apparent oxygen utilisation in the oligotrophic subtropical North Atlantic, Ocean Dynam., 55, 28–33, 2005.
Duteil, O., Koeve, W., Oschlies, A., Bianchi, D., Galbraith, E., Kriest, I., and Matear, R.: A novel estimate of ocean oxygen utilisation points to a reduced rate of respiration in the ocean interior, Biogeosciences, 10, 7723–7738, https://doi.org/10.5194/bg-10-7723-2013, 2013.
Edwards, N. and Marsh, R.: Uncertainties due to transport-parameter sensitivity in an efficient 3-D ocean-climate model, Clim. Dynam., 24, 415–433, 2005.
Feely, R., Sabine, C., Schlitzer, R., Bullister, J., Mecking, S., and Greely, D.: Oxygen utilization and organic carbon remineralization in the upper water column of the Pacific Ocean, J. Oceanogr., 60, 45–52, 2004.
Garcia, H., Locarnini, R., Boyer, T., Antonov, J., Zweng, M., Baranova, O., and Johnson, D.: World Ocean Atlas 2009, Volume 4: Nutrients (phosphate, nitrate, silicate), in: NOAA Atlas NESDIS 71, edited by: Levitus, S., U.S. Government Printing Office, Washington, DC, 398 pp., 2010.
Gebbie, G. and Huybers, P.: Total matrix intercomparison: a method for determining the geometry of water-mass pathways, J. Phys. Oceanogr., 40, 1710–1728, https://doi.org/10.1175/2010JPO4272.1, 2010.
Gebbie, G. and Huybers, P.: The Mean Age of Ocean Waters Inferred from Radiocarbon Observations: Sensitivity to Surface Sources and Accounting for Mixing Histories, J. Phys. Oceanogr., 42, 291–305, https://doi.org/10.1175/JPO-D-11-043.1, 2012.
Hansell, D., Carlson, C., Repeta, D., and Schlitzer, R.: Dissolved organic matter in the ocean: a controversy stimulates new insights, Oceanography, 22, 202–211, 2009.
Henson, S., Sanders, R., and Madsen, E.: Global patterns in efficiency of particulate organic carbon export and transfer to the deep ocean, Global Biogeochem. Cy., 26, GB1028, https://doi.org/10.1029/2011GB004099, 2012.
Henson, S. A., Sanders, R., Madsen, E., Morris, P. J., Le Moigne, F., and Quartly, G. D.: A reduced estimate of the strength of the ocean's biological carbon pump, Geophys. Res. Lett., 38, L04606, https://doi.org/10.1029/2011GL046735, 2011.
Honjo, S., Manganini, S. J., Krishfield, R. A., and Francois, R.: Particulate organic carbon fluxes to the ocean interior and factors controlling the biological pump: a synthesis of global sediment trap programs since 1983, Prog. Oceanogr., 76, 217–285, https://doi.org/10.1016/j.pocean.2007.11.003, 2008.
Honjo, S., Eglinton, T., Taylor, C., Ulmer, K., Sievert, S., Bracher, A., German, C., Edgcomb, V., Francois, R., Iglesias-Rodriguez, M., Van Mooy, B., and Repeta, D.: Understanding the role of the biological pump in the global carbon cycle: an imperative for ocean science, Oceanography, 27, 10–16, 2014.
Ito, T., Follows, M. J., and Boyle, E. A.: Is AOU a good measure of respiration in the oceans?, Geophys. Res. Lett., 31, L17305, https://doi.org/10.1029/2004GL020900, 2004.
Jenkins, W. J.: Oxygen utilization rates in North Atlantic subtropical gyre and primary production in oligotrophic systems, Nature, 300, 246–248, https://doi.org/10.1038/300246a0, 1982.
Jin, X., Gruber, N., Dunne, J. P., Sarmiento, J. L., and Armstrong, R. A.: Diagnosing the contribution of phytoplankton functional groups to the production and export of particulate organic carbon, CaCO3, and opal from global nutrient and alkalinity distributions, Global Biogeochem. Cy., 20, GB2015, https://doi.org/10.1029/2005GB002532, 2006.
Khatiwala, S.: A computational framework for simulation of biogeochemical tracers in the ocean, Deep-Sea Res. Pt. I, 53, 1335–1343, https://doi.org/10.1016/j.dsr.2006.06.003, 2006.
Khatiwala, S., Visbeck, M., and Cane, M. A.: Accelerated simulation of passive tracers in ocean circulation models, Ocean Model., 9, 51–69, https://doi.org/10.1016/j.ocemod.2004.04.002, 2005.
Klaas, C. and Archer, D. E.: Association of sinking organic matter with various types of mineral ballast in the deep sea: implications for the rain ratio, Global Biogeochem. Cy., 16, 1116, https://doi.org/10.1029/2001GB001765, 2002.
Kriest, I., Khatiwala, S. and Oschlies, A.: Towards an assessment of simple global marine biogeochemical models of different complexity, Prog. Oceanogr., 86, 337–360, https://doi.org/10.1016/j.pocean.2010.05.002, 2010.
Kriest, I., Oschlies, A., and Khatiwala, S.: Sensitivity analysis of simple global marine biogeochemical models, Global Biogeochem. Cy., 26, GB2029, https://doi.org/10.1029/2011GB004072, 2012.
Kwon, E. Y. and Primeau, F.: Optimization and sensitivity study of a biogeochemistry ocean model using an implicit solver and in situ phosphate data, Global Biogeochem. Cy., 20, GB4009, https://doi.org/10.1029/2005GB002631, 2006.
Kwon, E. Y., Primeau, F., and Sarmiento, J. L.: The impact of remineralization depth on the air-sea carbon balance, Nat. Geosci., 2, 630–635, https://doi.org/10.1038/ngeo612, 2009.
Lam, P. J., Doney, S. C., and Bishop, J. K. B.: The dynamic ocean biological pump: insights from a global compilation of particulate organic carbon, CaCO3, and opal concentration profiles from the mesopelagic, Global Biogeochem. Cy., 25, GB3009, https://doi.org/10.1029/2010GB003868, 2011.
Le Moigne, F. A. C., Sanders, R. J., Villa-Alfageme, M., Martin, A. P., Pabortsava, K., Planquette, H., Morris, P. J., and Thomalla, S. J.: On the proportion of ballast versus non-ballast associated carbon export in the surface ocean, Geophys. Res. Lett., 39, L15610, https://doi.org/10.1029/2012GL052980, 2012.
Lutz, M., Caldeira, K., Dunbar, R., and Behrenfeld, M.: Seasonal rhythms of net primary production and particulate organic carbon flux to depth describe the efficiency of biological pump in the global ocean, J. Geophys. Res.-Oceans, 112, C10011, https://doi.org/10.1029/2006JC003706, 2007.
Marsay, C. M., Sanders, R. J., Henson, S. A., Pabortsava, K., Achterberg, E. P., and Lampitt, R. S.: Attenuation of sinking particulate organic carbon flux through the mesopelagic ocean, P. Natl. Acad. Sci. USA, 112, 1089–1094, https://doi.org/10.1073/pnas.1415311112, 2015.
Martin, J., Knauer, G., Karl, D. M., and Broenkow, W.: VERTEX: carbon cycling in the northeast Pacific, Deep-Sea Res., 43, 267–285, 1987. \bibitem[Najjar et al.(2007) Najjar,Jin,Louanchi,Aumont,Caldeira,Doney,Dutay,Follows,Gruber,Joos,Lindsay,Maier-Reimer,Matear,Matsumoto,Monfray,Mouchet,Orr,Plattner,Sarmiento,Schlitzer,Slater,Weirig,Yamanaka and Yool] Najjar2007 Najjar, R. G., Jin, X., Louanchi, F., Aumont, O., Caldeira, K., Doney, S. C., Dutay, J.-C., Follows, M., Gruber, N., Joos, F., Lindsay, K., Maier-Reimer, E., Matear, R. J., Matsumoto, K., Monfray, P., Mouchet, A., Orr, J. C., Plattner, G.-K., Sarmiento, J. L., Schlitzer, R., Slater, R. D., Weirig, M.-F., Yamanaka, Y. and Yool, A.: Impact of circulation on export production, dissolved organic matter, and dissolved oxygen in the ocean: Results from Phase II of the Ocean Carbon-cycle Model Intercomparison Project (OCMIP-2), Global Biogeochem. Cy., 21, GB3007, https://doi.org/10.1029/2006GB002857, 2007.
Olli, K.: Unraveling the uncertainty and error propagation in the vertical flux Martin curve, Prog. Oceanogr., 135, 146–156, https://doi.org/10.1016/j.pocean.2015.05.016, 2015.
Passow, U.: Switching perspectives: do mineral fluxes determine particulate organic carbon fluxes or vice versa?, Geochem. Geophy. Geosy., 5, Q04002, https://doi.org/10.1029/2003GC000670, 2004.
Primeau, P.: n the variability of the exponent in the power law depth dependence of (POC) flux estimated from sediment traps, Global Biogeochem. Cy., 21, GB3001, https://doi.org/10.1029/2007GB002923, 2007.
Ridgwell, A., Hargreaves, J. C., Edwards, N. R., Annan, J. D., Lenton, T. M., Marsh, R., Yool, A., and Watson, A.: Marine geochemical data assimilation in an efficient Earth System Model of global biogeochemical cycling, Biogeosciences, 4, 87–104, https://doi.org/10.5194/bg-4-87-2007, 2007a.
Ridgwell, A., Zondervan, I., Hargreaves, J. C., Bijma, J., and Lenton, T. M.: Assessing the potential long-term increase of oceanic fossil fuel CO2 uptake due to CO2-calcification feedback, Biogeosciences, 4, 481–492, https://doi.org/10.5194/bg-4-481-2007, 2007b.
Roth, R., Ritz, S. P., and Joos, F.: Burial-nutrient feedbacks amplify the sensitivity of atmospheric carbon dioxide to changes in organic matter remineralisation, Earth Syst. Dynam., 5, 321–343, https://doi.org/10.5194/esd-5-321-2014, 2014.
Sarmiento, J., Gruber, N., Brzezinski, M., and Dunne, J.: High-latitude controls of thermocline nutrients and low latitude biological productivity, Nature, 427, 56–60, https://doi.org/10.1038/nature02127, 2004.
Sarmiento, J. L., Dunne, J., Gnanadesikan, A., Key, R. M., Matsumoto, K., and Slater, R.: A new estimate of the CaCO3 to organic carbon export ratio, Global Biogeochem. Cy., 16, 54-1–54-12, https://doi.org/10.1029/2002GB001919, 2002.
Schlitzer, R.: Carbon export fluxes in the Southern Ocean: results from inverse modeling and comparison with satellite based estimates, Deep-Sea Res. Pt. II, 49, 1623–1644, 2002.
Sonnerup, R. E., Mecking, S., and Bullister, J. L.: Transit time distributions and oxygen utilization rates in the Northeast Pacific Ocean from chlorofluorocarbons and sulfur hexafluoride, Deep-Sea Res. Pt. I, 72, 61–71, https://doi.org/10.1016/j.dsr.2012.10.013, 2013.
Stammer, D., Ueyoshi, K., Köhl, A., Large, W. G., Josey, S. A., and Wunsch, C.: Estimating air-sea fluxes of heat, freshwater, and momentum through global ocean data assimilation, J. Geophys. Res.-Oceans, 109, C05023, https://doi.org/10.1029/2003JC002082, 2004.
Stanley, R. H. R., Doney, S. C., Jenkins, W. J., and Lott III, D. E.: Apparent oxygen utilization rates calculated from tritium and helium-3 profiles at the Bermuda Atlantic Time-series Study site, Biogeosciences, 9, 1969–1983, https://doi.org/10.5194/bg-9-1969-2012, 2012.
Suess, E.: Particulate organic carbon flux in the oceans – surface productivity and oxygen utilization, Nature, 288, 5788, 260–263, https://doi.org/10.1038/288260a0, 1980.
Teng, Y.-C., Primeau, F., Moore, J., Lomas, M., and Martiny, A.: Global-scale variations of the ratios of carbon to phosphorus in exported marine organic matter, Nat. Geosci., 7, 895–898, https://doi.org/10.1038/ngeo2303, 2014.
Wilson, J. D., Barker, S., and Ridgwell, A.: Assessment of the spatial variability in particulate organic matter and mineral sinking fluxes in the ocean interior: implications for the ballast hypothesis, Global Biogeochem. Cy., 26, GB4011, https://doi.org/10.1029/2012GB004398, 2012.
Yao, X. and Schlitzer, R.: Assimilating water column and satellite data for marine export production estimation, Geosci. Model Dev., 6, 1575–1590, https://doi.org/10.5194/gmd-6-1575-2013, 2013.
Zeebe, R. E.: LOSCAR: Long-term Ocean-atmosphere-Sediment CArbon cycle Reservoir Model v2.0.4, Geosci. Model Dev., 5, 149–166, https://doi.org/10.5194/gmd-5-149-2012, 2012.
Short summary
We explore whether ocean model transport rates, in the form of a transport matrix, can be used to estimate remineralisation rates from dissolved nutrient concentrations and infer vertical fluxes of particulate organic carbon. Estimated remineralisation rates are significantly sensitive to uncertainty in the observations and the modelled circulation. The remineralisation of dissolved organic matter is an additional source of uncertainty when inferring vertical fluxes from remineralisation rates.
We explore whether ocean model transport rates, in the form of a transport matrix, can be used...
Altmetrics
Final-revised paper
Preprint