Articles | Volume 15, issue 20
https://doi.org/10.5194/bg-15-6049-2018
© Author(s) 2018. 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-15-6049-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
16 Oct 2018
Research article |
| 16 Oct 2018
| 16 Oct 2018
Mechanisms of northern North Atlantic biomass variability
Galen A. McKinley
CORRESPONDING AUTHOR
Department of Atmospheric and Oceanic Sciences, University of
Wisconsin–Madison, Madison, Wisconsin, USA
now at: Columbia University and Lamont Doherty Earth Observatory, New
York, USA
Alexis L. Ritzer
Department of Atmospheric and Oceanic Sciences, University of
Wisconsin–Madison, Madison, Wisconsin, USA
Nicole S. Lovenduski
Department of Atmospheric and Oceanic Sciences and Institute of Arctic
and Alpine Research, University of Colorado Boulder, Boulder, Colorado, USA
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Measurements of ocean carbon are limited in time and space. Machine learning algorithms are therefore used to reconstruct ocean carbon where observations do not exist. Improving these reconstructions is important in order to accurately estimate how much carbon the ocean absorbs from the atmosphere. In this study, we find that that a small addition of observations from the Southern Ocean, obtained by autonomous sampling platforms, could significantly improve the reconstructions.
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The movement of carbon dioxide from the atmosphere to the ocean is estimated using surface ocean carbon (pCO2) measurements and an equation including variables such as temperature and wind speed; the choices of these variables lead to uncertainties. We introduce the SeaFlux ensemble which provides carbon flux maps calculated in a consistent manner, thus reducing uncertainty by using common choices for wind speed and a set definition of "global" coverage.
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Approximately 40 % of the CO2 emissions from fossil fuel combustion and cement production have been absorbed by the ocean. The goal of the UNFCCC Paris Agreement is to reduce humanity's emissions so as to limit global warming to no more than 2 °C, and ideally less than 1.5 °C. If we achieve this level of mitigation, the ocean's uptake of carbon will be strongly reduced. Excess carbon trapped in the near-surface ocean will begin to mix back to the surface and will limit additional uptake.
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Using simulated surface ocean pCO2 from Earth System Models, we test three Machine Learning methods (neural network, XGBoost, random forest) to discern their ability to reconstruct global coverage from sparse observations. Synthetic data means we can train based on real-world sampling patterns and then evaluate against the known full coverage result of the original simulation. ML approaches perform best in the open ocean, but struggle in regions of low sampling. XGBoost saw the best performance.
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Colleen B. Mouw, Audrey Barnett, Galen A. McKinley, Lucas Gloege, and Darren Pilcher
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Particulate organic carbon (POC) flux estimated from POC concentration observations from sediment traps and 234Th are compiled across the global ocean. By providing merged coincident satellite imagery products, the dataset can be used to link phytoplankton surface process with POC flux. Due to rapid remineralization within the first 500 m of the water column, shallow observations from 234Th supplement the more extensive sediment trap record.
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Skyler Kern, Mary E. McGuinn, Katherine M. Smith, Nadia Pinardi, Kyle E. Niemeyer, Nicole S. Lovenduski, and Peter E. Hamlington
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Computational models are used to simulate the behavior of marine ecosystems. The models often have unknown parameters that need to be calibrated to accurately represent observational data. Here, we propose a novel approach to simultaneously determine a large set of parameters for a one-dimensional model of a marine ecosystem in the surface ocean at two contrasting sites. By utilizing global and local optimization techniques, we estimate many parameters in a computationally efficient manner.
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Earth Syst. Sci. Data, 15, 5301–5369, https://doi.org/10.5194/essd-15-5301-2023, https://doi.org/10.5194/essd-15-5301-2023, 2023
Short summary
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The Global Carbon Budget 2023 describes the methodology, main results, and data sets used to quantify the anthropogenic emissions of carbon dioxide (CO2) and their partitioning among the atmosphere, land ecosystems, and the ocean over the historical period (1750–2023). These living datasets are updated every year to provide the highest transparency and traceability in the reporting of CO2, the key driver of climate change.
Geneviève W. Elsworth, Nicole S. Lovenduski, Kristen M. Krumhardt, Thomas M. Marchitto, and Sarah Schlunegger
Biogeosciences, 20, 4477–4490, https://doi.org/10.5194/bg-20-4477-2023, https://doi.org/10.5194/bg-20-4477-2023, 2023
Short summary
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Anthropogenic climate change will influence marine phytoplankton over the coming century. Here, we quantify the influence of anthropogenic climate change on marine phytoplankton internal variability using an Earth system model ensemble and identify a decline in global phytoplankton biomass variance with warming. Our results suggest that climate mitigation efforts that account for marine phytoplankton changes should also consider changes in phytoplankton variance driven by anthropogenic warming.
Amanda R. Fay, David R. Munro, Galen A. McKinley, Denis Pierrot, Stewart C. Sutherland, Colm Sweeney, and Rik Wanninkhof
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2023-429, https://doi.org/10.5194/essd-2023-429, 2023
Revised manuscript accepted for ESSD
Short summary
Short summary
Presented here is a near-global monthly estimate of the difference between atmosphere and ocean carbon dioxide concentrations. The ocean's ability to take up carbon, both now and in the future, is defined by this difference in concentrations. With over 30 million measurements of surface ocean carbon over the last 40 years, and utilization of an extrapolation technique, a mean estimate of surface ocean delta fCO2 is presented.
Thea Hatlen Heimdal, Galen A. McKinley, Adrienne J. Sutton, Amanda R. Fay, and Lucas Gloege
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-160, https://doi.org/10.5194/bg-2023-160, 2023
Revised manuscript accepted for BG
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Measurements of ocean carbon are limited in time and space. Machine learning algorithms are therefore used to reconstruct ocean carbon where observations do not exist. Improving these reconstructions is important in order to accurately estimate how much carbon the ocean absorbs from the atmosphere. In this study, we find that that a small addition of observations from the Southern Ocean, obtained by autonomous sampling platforms, could significantly improve the reconstructions.
István Dunkl, Nicole Lovenduski, Alessio Collalti, Vivek K. Arora, Tatiana Ilyina, and Victor Brovkin
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Stephen G. Yeager, Nan Rosenbloom, Anne A. Glanville, Xian Wu, Isla Simpson, Hui Li, Maria J. Molina, Kristen Krumhardt, Samuel Mogen, Keith Lindsay, Danica Lombardozzi, Will Wieder, Who M. Kim, Jadwiga H. Richter, Matthew Long, Gokhan Danabasoglu, David Bailey, Marika Holland, Nicole Lovenduski, Warren G. Strand, and Teagan King
Geosci. Model Dev., 15, 6451–6493, https://doi.org/10.5194/gmd-15-6451-2022, https://doi.org/10.5194/gmd-15-6451-2022, 2022
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The Earth system changes over a range of time and space scales, and some of these changes are predictable in advance. Short-term weather forecasts are most familiar, but recent work has shown that it is possible to generate useful predictions several seasons or even a decade in advance. This study focuses on predictions over intermediate timescales (up to 24 months in advance) and shows that there is promising potential to forecast a variety of changes in the natural environment.
Amanda R. Fay, Luke Gregor, Peter Landschützer, Galen A. McKinley, Nicolas Gruber, Marion Gehlen, Yosuke Iida, Goulven G. Laruelle, Christian Rödenbeck, Alizée Roobaert, and Jiye Zeng
Earth Syst. Sci. Data, 13, 4693–4710, https://doi.org/10.5194/essd-13-4693-2021, https://doi.org/10.5194/essd-13-4693-2021, 2021
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The movement of carbon dioxide from the atmosphere to the ocean is estimated using surface ocean carbon (pCO2) measurements and an equation including variables such as temperature and wind speed; the choices of these variables lead to uncertainties. We introduce the SeaFlux ensemble which provides carbon flux maps calculated in a consistent manner, thus reducing uncertainty by using common choices for wind speed and a set definition of "global" coverage.
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Jake Stamell, Rea R. Rustagi, Lucas Gloege, and Galen A. McKinley
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Revised manuscript not accepted
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Using simulated surface ocean pCO2 from Earth System Models, we test three Machine Learning methods (neural network, XGBoost, random forest) to discern their ability to reconstruct global coverage from sparse observations. Synthetic data means we can train based on real-world sampling patterns and then evaluate against the known full coverage result of the original simulation. ML approaches perform best in the open ocean, but struggle in regions of low sampling. XGBoost saw the best performance.
Lester Kwiatkowski, Olivier Torres, Laurent Bopp, Olivier Aumont, Matthew Chamberlain, James R. Christian, John P. Dunne, Marion Gehlen, Tatiana Ilyina, Jasmin G. John, Andrew Lenton, Hongmei Li, Nicole S. Lovenduski, James C. Orr, Julien Palmieri, Yeray Santana-Falcón, Jörg Schwinger, Roland Séférian, Charles A. Stock, Alessandro Tagliabue, Yohei Takano, Jerry Tjiputra, Katsuya Toyama, Hiroyuki Tsujino, Michio Watanabe, Akitomo Yamamoto, Andrew Yool, and Tilo Ziehn
Biogeosciences, 17, 3439–3470, https://doi.org/10.5194/bg-17-3439-2020, https://doi.org/10.5194/bg-17-3439-2020, 2020
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We assess 21st century projections of marine biogeochemistry in the CMIP6 Earth system models. These models represent the most up-to-date understanding of climate change. The models generally project greater surface ocean warming, acidification, subsurface deoxygenation, and euphotic nitrate reductions but lesser primary production declines than the previous generation of models. This has major implications for the impact of anthropogenic climate change on marine ecosystems.
Riley X. Brady, Nicole S. Lovenduski, Michael A. Alexander, Michael Jacox, and Nicolas Gruber
Biogeosciences, 16, 329–346, https://doi.org/10.5194/bg-16-329-2019, https://doi.org/10.5194/bg-16-329-2019, 2019
Nicole S. Lovenduski, Stephen G. Yeager, Keith Lindsay, and Matthew C. Long
Earth Syst. Dynam., 10, 45–57, https://doi.org/10.5194/esd-10-45-2019, https://doi.org/10.5194/esd-10-45-2019, 2019
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This paper shows that the absorption of carbon dioxide by the ocean is predictable several years in advance. This is important because fossil-fuel-derived carbon dioxide is largely responsible for anthropogenic global warming and because carbon dioxide emission management and global carbon cycle budgeting exercises can benefit from foreknowledge of ocean carbon absorption. The promising results from this new forecast system justify the need for additional oceanic observations.
Amanda R. Fay, Nicole S. Lovenduski, Galen A. McKinley, David R. Munro, Colm Sweeney, Alison R. Gray, Peter Landschützer, Britton B. Stephens, Taro Takahashi, and Nancy Williams
Biogeosciences, 15, 3841–3855, https://doi.org/10.5194/bg-15-3841-2018, https://doi.org/10.5194/bg-15-3841-2018, 2018
Short summary
Short summary
The Southern Ocean is highly under-sampled and since this region dominates the ocean sink for CO2, understanding change is critical. Here we utilize available observations to evaluate how the seasonal cycle, variability, and trends in surface ocean carbon in the well-sampled Drake Passage region compare to that of the broader subpolar Southern Ocean. Results indicate that the Drake Passage is representative of the broader region; however, additional winter observations would improve comparisons.
Giuliana Turi, Michael Alexander, Nicole S. Lovenduski, Antonietta Capotondi, James Scott, Charles Stock, John Dunne, Jasmin John, and Michael Jacox
Ocean Sci., 14, 69–86, https://doi.org/10.5194/os-14-69-2018, https://doi.org/10.5194/os-14-69-2018, 2018
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A high-resolution global model was used to study the influence of El Niño/La Niña events on the California Current System (CalCS). The mean surface oxygen (O2) response extends well offshore, where the pH response occurs within ~ 100 km of the coast. The surface O2 (pH) is primarily driven by temperature (upwelling) changes. Below 100 m, anomalously low O2 and low pH occurred during La Niña events near the coast, potentially stressing the ecosystem, but there are large variations between events.
Colleen B. Mouw, Audrey Barnett, Galen A. McKinley, Lucas Gloege, and Darren Pilcher
Earth Syst. Sci. Data, 8, 531–541, https://doi.org/10.5194/essd-8-531-2016, https://doi.org/10.5194/essd-8-531-2016, 2016
Short summary
Short summary
Particulate organic carbon (POC) flux estimated from POC concentration observations from sediment traps and 234Th are compiled across the global ocean. By providing merged coincident satellite imagery products, the dataset can be used to link phytoplankton surface process with POC flux. Due to rapid remineralization within the first 500 m of the water column, shallow observations from 234Th supplement the more extensive sediment trap record.
Melissa L. Breeden and Galen A. McKinley
Biogeosciences, 13, 3387–3396, https://doi.org/10.5194/bg-13-3387-2016, https://doi.org/10.5194/bg-13-3387-2016, 2016
Short summary
Short summary
Natural variability of the North Atlantic carbon cycle is modeled for 1948–2009. The dominant mode of surface ocean CO2 variability is associated with sea surface temperature (SST) variability composed of (a) the Atlantic Multidecadal Oscillation (AMO) and (b) a positive SST trend. In the subpolar gyre, positive AMO is associated with reduced vertical mixing that lowers pCO2. In the subtropical gyre, AMO-associated warming increases pCO2. Since 1980, the SST trend has amplified AMO impacts.
Natalie M. Freeman and Nicole S. Lovenduski
Earth Syst. Sci. Data, 8, 191–198, https://doi.org/10.5194/essd-8-191-2016, https://doi.org/10.5194/essd-8-191-2016, 2016
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The Antarctic Polar Front (PF) is an important physical and biogeochemical divide in the Southern Ocean, delineating distinct zones of temperature, nutrients and biological communities. Our study learns from and advances previous efforts to locate the PF via satellite by avoiding cloud contamination and providing circumpolar realizations at high spatio-temporal resolution. These realizations are consistent with concurrent in situ PF locations and previously published climatological PF positions.
Kristen M. Krumhardt, Nicole S. Lovenduski, Natalie M. Freeman, and Nicholas R. Bates
Biogeosciences, 13, 1163–1177, https://doi.org/10.5194/bg-13-1163-2016, https://doi.org/10.5194/bg-13-1163-2016, 2016
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In this study, we combine phytoplankton pigment data with particulate inorganic carbon and chlorophyll measurements from the satellite record to assess recent trends in phytoplankton dynamics in the North Atlantic subtropical gyre, with a focus on coccolithophores. We show that coccolithophores in the North Atlantic have been increasing in abundance. Correlations suggest that they are responding positively to increasing inorganic carbon from anthropogenic inputs in the upper mixed layer.
N. S. Lovenduski, M. C. Long, and K. Lindsay
Biogeosciences, 12, 6321–6335, https://doi.org/10.5194/bg-12-6321-2015, https://doi.org/10.5194/bg-12-6321-2015, 2015
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We investigate variability in surface ocean carbonate chemistry using output from a 1000-year control simulation of an Earth System Model. We find that the detection timescale for trends is strongly influenced by the variability. As the scientific community seeks to detect the anthropogenic influence on ocean carbonate chemistry, these results will aid the interpretation of trends calculated from spatially and temporally sparse observations.
A. R. Fay and G. A. McKinley
Earth Syst. Sci. Data, 6, 273–284, https://doi.org/10.5194/essd-6-273-2014, https://doi.org/10.5194/essd-6-273-2014, 2014
A. Lenton, B. Tilbrook, R. M. Law, D. Bakker, S. C. Doney, N. Gruber, M. Ishii, M. Hoppema, N. S. Lovenduski, R. J. Matear, B. I. McNeil, N. Metzl, S. E. Mikaloff Fletcher, P. M. S. Monteiro, C. Rödenbeck, C. Sweeney, and T. Takahashi
Biogeosciences, 10, 4037–4054, https://doi.org/10.5194/bg-10-4037-2013, https://doi.org/10.5194/bg-10-4037-2013, 2013
S. Khatiwala, T. Tanhua, S. Mikaloff Fletcher, M. Gerber, S. C. Doney, H. D. Graven, N. Gruber, G. A. McKinley, A. Murata, A. F. Ríos, and C. L. Sabine
Biogeosciences, 10, 2169–2191, https://doi.org/10.5194/bg-10-2169-2013, https://doi.org/10.5194/bg-10-2169-2013, 2013
R. Wanninkhof, G. -H. Park, T. Takahashi, C. Sweeney, R. Feely, Y. Nojiri, N. Gruber, S. C. Doney, G. A. McKinley, A. Lenton, C. Le Quéré, C. Heinze, J. Schwinger, H. Graven, and S. Khatiwala
Biogeosciences, 10, 1983–2000, https://doi.org/10.5194/bg-10-1983-2013, https://doi.org/10.5194/bg-10-1983-2013, 2013
U. Schuster, G. A. McKinley, N. Bates, F. Chevallier, S. C. Doney, A. R. Fay, M. González-Dávila, N. Gruber, S. Jones, J. Krijnen, P. Landschützer, N. Lefèvre, M. Manizza, J. Mathis, N. Metzl, A. Olsen, A. F. Rios, C. Rödenbeck, J. M. Santana-Casiano, T. Takahashi, R. Wanninkhof, and A. J. Watson
Biogeosciences, 10, 607–627, https://doi.org/10.5194/bg-10-607-2013, https://doi.org/10.5194/bg-10-607-2013, 2013
Related subject area
Biogeochemistry: Open Ocean
Loss of nitrogen via anaerobic ammonium oxidation (anammox) in the California Current system during the late Quaternary
Technical note: Assessment of float pH data quality control methods – a case study in the subpolar northwest Atlantic Ocean
Linking northeastern North Pacific oxygen changes to upstream surface outcrop variations
Underestimation of multi-decadal global O2 loss due to an optimal interpolation method
Reviews and syntheses: expanding the global coverage of gross primary production and net community production measurements using Biogeochemical-Argo floats
Characteristics of surface physical and biogeochemical parameters within mesoscale eddies in the Southern Ocean
Phosphomonoesterase and phosphodiesterase activities in the Eastern Mediterranean Sea during stratified versus mixed conditions
Seasonal dynamics and annual budget of dissolved inorganic carbon in the northwestern Mediterranean deep-convection region
The fingerprint of climate variability on the surface ocean cycling of iron and its isotopes
Reconstructing the ocean's mesopelagic zone carbon budget: sensitivity and estimation of parameters associated with prokaryotic remineralization
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
Testing the influence of light on nitrite cycling rates in eastern tropical North Pacific
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)
Summer trends and drivers of sea surface fCO2 and pH changes observed in the southern Indian Ocean over the last two decades (1998–2019)
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
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.
Nicole M. Travis, Colette L. Kelly, and Karen L. Casciotti
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-64, https://doi.org/10.5194/bg-2023-64, 2023
Revised manuscript accepted for BG
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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.
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.
Coraline Leseurre, Claire Lo Monaco, Gilles Reverdin, Nicolas Metzl, Jonathan Fin, Claude Mignon, and Léa Benito
Biogeosciences, 19, 2599–2625, https://doi.org/10.5194/bg-19-2599-2022, https://doi.org/10.5194/bg-19-2599-2022, 2022
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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.
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.
Cited articles
Antonov, J. I., Locarnini, R. A., Boyer, T. P., Mishonov, A. V., and Garcia,
H. E.: World Ocean Atlas 2005, vol. 2, Salinity, NOAA Atlas NESDIS 62, edited
by: Levitus, S., US Govt. Print. Off., Washington, D. C., USA, 182 pp., 2006.
Behrenfeld, M. J.: Abandoning Sverdrup's Critical Depth Hypothesis on
phytoplankton blooms, Ecology, 91, 977–989, 2010.
Behrenfeld, M. J.: Climate-mediated dance of the plankton, Nat. Clim.
Change, 4, 880–887, 2014.
Behrenfeld, M. J. and Falkowski, P. G.: Photosynthetic rates derived from
satellite-based chlorophyll concentration, Limnol. Oceanogr., 42, 1479–1491, 1997.
Behrenfeld, M. J., Boss, E., Siegel, D. A., and Shea, D. M.: Carbon-based ocean
productivity and phytoplankton physiology from space, Global Biogeochem.
Cy. 19, GB1006, 2005.
Behrenfeld, M. J., O'Malley, R., Siegel, D., McClain, C., Sarmiento, J.,
Feldman, G., Milligan, A. J., Falkowski, P. G., Letelier, R. M., and Boss,
E. S.: Climate-driven trends in contemporary ocean productivity, Nature, 444,
752–755, 2006.
Behrenfeld, M. J., Doney, S. C., Lima, I., Boss, E. S., and Siegel, D. A.:
Annual cycles of ecological disturbance and recovery underlying the
subarctic Atlantic spring plankton bloom, Global Biogeochem. Cy., 27,
526–540, 2013.
Behrenfeld, M. J., Hu, Y., O'Malley, R. T., Boss, E. S., Hostetler, C. A.,
Siegel, D. A., Sarmiento, J. L., Schulien, J., Hair J. W., Lu, X., Rodier, S.,
and Scarino, A. J.: Annual boom–bust cycles of polar phytoplankton biomass
revealed by space-based lidar, Nat. Geosci., 10, 118–122, 2016.
Bennington, V., McKinley, G. A. , Dutkiewicz, S., and Ullman, D.: What does
chlorophyll variability tell us about export and CO2 flux variability
in the North Atlantic?, Global Biogeochem. Cycles 23, GB3002,
https://doi.org/10.1029/2008GB003241, 2009.
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.
Breeden, M. L. and McKinley, G. A.: Climate impacts on multidecadal
pCO2
variability in the North Atlantic: 1948–2009, Biogeosciences, 13, 3387–3396,
https://doi.org/10.5194/bg-13-3387-2016, 2016.
Comas-Bru, L. and McDermott, F.: Impacts of the EA and SCA patterns on the
European twentieth century NAO-winter climate relationship, Q. J. Roy.
Meteor. Soc., 140, 354–363, 2014.
Dave, A. C. and Lozier, M. S.: Local stratification control of marine
productivity in the subtropical North Pacific, J. Geophys. Res., 115,
C12032, https://doi.org/10.1029/2010JC006507, 2010.
Dave, A. C. and Lozier, M. S.: The impact of advection on stratification and
chlorophyll variability in the equatorial Pacific, Geophys. Res.
Lett., 42, 4523–4531, 2015.
Dave, A. C., Barton, A. D., Lozier, M. S., and McKinley, G. A.: What drives
seasonal change in oligotrophic area in the subtropical North Atlantic?, J.
Geophys. Res.-Oceans, 120, 3958–3969, https://doi.org/10.1002/2015JC010787, 2015.
Doney, S. C.: Plankton in a warmer world, Nature, 444, 695–696, 2006.
Dutkiewicz, S., Follows, M. J., Marshall, J., and Gregg, W. W.: Interannual
variability of phytoplankton abundances in the North Atlantic, Deep-Sea Res.
II, 48, 2323–2344, 2001.
Dutkiewicz, S., Follows, M. J., and Parekh, P.: Interactions of the iron and
phosphorus cycles: A three-dimensional model study, Global Biogeochem.
Cy., 19, GB1021, https://doi.org/10.1029/2004GB002342, 2005.
Eppley, R. W.: Temperature and phytoplankton growth in the sea, Fish. Bull.,
70, 1063, 1972.
Fay, A. R. and McKinley G. A.: Global trends in surface ocean pCO2 from in
situ data, Global Biogeochem. Cy., 27, 1–17, 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. and McKinley G. A.: Correlations of surface ocean pCO2 to satellite
chlorophyll on monthly to interannual timescales, Global Biogeochem. Cy., 31, 436–455, 2017.
Field, C. B., Behrenfeld, M. J., Randerson, J. T., and Falkowski, P.: Primary
Production of the Biosphere: Integrating Terrestrial and Oceanic Components,
Science, 281, 237–240, 1998.
Follows, M. J. and Dutkiewicz, S.: Meteorological modulation of the North
Atlantic spring bloom, Deep-Sea Res. II, 49, 321–344, 2002.
Fox-Kemper, B., Ferrari, R., and Hallberg, R. W.: Parameterization of mixed
layer eddies. Part I: Theory and diagnosis, J. Phys. Oceanogr., 38,
1145–1165, 2008.
Galbraith, E. D., Gnanadesikan, A., Dunne, J. P., and Hiscock, M. R.:
Regional impacts of iron-light colimitation in a global biogeochemical model,
Biogeosciences, 7, 1043–1064, https://doi.org/10.5194/bg-7-1043-2010, 2010.
Garcia, H. E., Locarnini, R. A., Boyer, T. P., and Antonov, J. I.: World Ocean
Atlas 2005, vol. 4, Nutrients (Phosphate, Nitrate, Silicate), NOAA Atlas
NESDIS 64, edited by: Levitus, S., U.S. Govt. Print. Off.,
Washington, D. C., USA, 396 pp., 2006.
Gent, P. R. and McWilliams, J. C.: Isopycnal mixing in ocean circulation
models, J. Phys. Oceanogr., 20, 150–155, 1990.
Häkkinen, S. and Rhines, P. B.: Decline of the subpolar North Atlantic
circulation during the 1990s, Science, 304, 555–559, 2004.
Hátún, H., Sandø, A. B., Drange, H., Hansen, B., and Valdimarsson,
H.: Influence of the Atlantic subpolar gyre on the thermohaline circulation,
Science, 309, 1841–1844, 2005.
Hátún, H., Lohmann, K., Matei, D., Jungclaus, J., Pacariz, S.,
Bersch, M., Gislason, A., Olafsson, J., and Reid, R. C : An inflated subpolar gyre blows
life toward the northeastern Atlantic, Prog. Oceanogr., 147, 49–66,
2016.
Hátún, H. Azetsu-Scott, K., Somavilla, R., Rey, F., Johnson, C.,
Mathis, M., Mikolajewicz, U., Coupel, P., Tremblay, J., Hartman, S., Pacariz, S. V.,
Salter, I., and Olafsson, J.: The subpolar gyre regulates silicate
concentrations in the North Atlantic, Sci. Rep., 7, 14576,
https://doi.org/10.1038/s41598-017-14837-4, 2017.
Hunter-Cevera, K. R., Neubert, M. G., Olson, R. J., Solow, A. R., Shalapyonok,
A., and Sosik, H. M.: Physiological and ecological drivers of early spring
blooms of a coastal phytoplankter, Science, 354, 326–329, 2016.
Hurrell, J. and NCAR: The Climate Data Guide: Hurrell North Atlantic
Oscillation (NAO) index (station based), available at:
https://climatedataguide.ucar.edu/climate-data/hurrell-north-atlantic-oscillation-nao-index-station-based, last access: 15 December 2017.
Johnson, C., Inall, M., and Häkkinen, S.: Declining nutrient
concentrations in the northeast Atlantic as a result of a weakening Subpolar
Gyre, Deep-Sea Res. Pt. I, 82, 95–107, 2013.
Johnson, K. S., Berelson, W. M., Boss, E. S., Chase, Z., Claustre, H.,
Emerson, S. R., Gruber, N., Koertzinger, A., Perry, M. J., and Riser, S. C.:
Observing biogeochemical cycles at global scales with profiling floats and
gliders prospects for a global array, Oceanography, 22, 216–225,
https://doi.org/10.5670/oceanog.2009.81, 2009.
Kalnay, E., Kanamitsu, M., Kistler, R., Collins, W., Deaven, D., Gandin, L.,
Iredell, M., Saha, S., White, G., Woollen, J., Zhu, Y., Leetmaa, A., and
Reynolds, R.: The NCAR/NECP 40-year reanalysis project, B. Am. Meteor.
Soc., 77, 437–471, 1996.
Koch, J., McKinley, G. A., Bennington, V., and Ullman, D.: Do hurricanes cause
significant interannual variability in the air-sea CO2 flux of the
subtropical North Atlantic?, Geophys. Res. Lett., 36, L07606, https://doi.org/10.1029/2009GL037553, 2009.
Large, W. G., McWilliams, J. C., and Doney, S. C.: Oceanic vertical mixing: A
review and a model with a nonlocal boundary layer parameterization, Rev.
Geophys., 32, 363–403, 1994.
Laufkötter, C., Vogt, M., Gruber, N., Aita-Noguchi, M., Aumont, O., Bopp, L.,
Buitenhuis, E., Doney, S. C., Dunne, J., Hashioka, T., Hauck, J., Hirata, T.,
John, J., Le Quéré, C., Lima, I. D., Nakano, H., Seferian, R., Totterdell,
I., Vichi, M., and Völker, C.: Drivers and uncertainties of future global
marine primary production in marine ecosystem models, Biogeosciences, 12,
6955–6984, https://doi.org/10.5194/bg-12-6955-2015, 2015.
Long, M. C., Lindsay, K., Peacock, S., Moore, J. K., and Doney, S. C.:
Twentieth-Century Oceanic Carbon Uptake and Storage in CESM1(BGC), J.
Climate, 26, 6775–6800, https://doi.org/10.1175/JCLI-D-12-00184.1, 2013.
Lozier, M. S., Leadbetter, S., Williams, R. G., Roussenov, V., Reed, M. S. C.,
and Moore, N. J.: The spatial pattern and mechanisms of heat-content change
in the North Atlantic, Science, 319, 800–803, 2008.
Lozier, M. S., Dave, A. C., Palter, J. B., Gerber, L. M., and Barber, R. T.: On
the relationship between stratification and primary productivity in the
North Atlantic, Geophys. Res. Lett., 38, L18609, https://doi.org/10.1029/2011GL049414,
2011.
Mahadevan, A., D'Asaro, E., Lee, C., and Perry, M. J.: Eddy-driven
stratification initiates North Atlantic spring phytoplankton blooms, Science,
337, 54–58, 2012.
Mahowald, N., Lou, C., del Corral, J., and Zender, C.: Interannual
variability in atmospheric mineral aerosols from a 22-year model simulation
and observational data, J. Geophys. Res., 108, 4352,
https://doi.org/10.1029/2002JD002821, 2003.
Marshall, J. C., Adcroft, A., Hill, C., Perelman, L., and Heisey, C.: A
finite volume, incompressible Navier-Stokes model for studies of the ocean
on parallel computers, J. Geophys. Res., 102, 5753–5766, 1997a.
Marshall, J. C., Hill, C., Perelman, L., and Adcroft, A.: Hydrostatic,
quasi-hydrstatic and non-hydrostatic ocean modeling, J. Geophys. Res., 102,
5733–5752, 1997b.
Martinez, E., Antoine, D., D'Ortenzio, F., and Gentili, B.: Climate-driven
basin-scale decadal oscillations of oceanic phytoplankton, Science, 326,
1253–1256, 2009.
McClain, C. R., Feldman, G. C., and Hooker, S. B.: An overview of the SeaWiFS
project and strategies for producing a climate research quality global ocean
bio-optical time series, Deep-Sea Res. Pt. II, 51, 5–42, 2004.
McGillicuddy Jr., D. J., Anderson, L. A., Doney, S. C., and Maltrud, M. E.:
Eddy-driven sources and sinks of nutrients in the upper ocean: Results from
a 0.1∘ resolution model of the North Atlantic, Global Biogeochem.
Cy., 17, 1035, https://doi.org/10.1029/2002GB001987, 2003.
Mignot, A., Ferrari, R., and Claustre, H.: Floats with bio-optical sensors
reveal what processes trigger the North Atlantic bloom, Nat. Commun., 9,
190, https://doi.org/10.1038/s41467-017-02143-6, 2018.
MITgcm: MITgcm codebase, available at: http://mitgcm.org/, last access:
15 October 2018.
Ocean Productivity: Satellite data, available at: http://www.science.oregonstate.edu/ocean.productivity/index.php, last access:
15 October 2018.
Oschlies, A.: Nutrient supply to the surface waters of the North Atlantic: A
model study, J. Geophys. Res., 107, 1106, https://doi.org/10.1029/2000JC000275, 2002.
Palter, J. B., Lozier, M. S., and Barber, R. T.: The effect of advection on the
nutrient reservoir in the North Atlantic subtropical gyre, Nature, 437,
687–692, 2005.
Pelegrí, J. L., Csanady, G. T., and Martins, A.: The North Atlantic
nutrient stream, J. Oceanogr., 52, 275–299, 1996.
Rayner, N. A., Parker, D. E., Horton, E. B., Folland, C. K., Alexander, L. V.,
Rowell, D. P., Kent, E. C., and Kaplan, A.: Global analyses of sea surface
temperature, sea ice, and night marine air temperature since the late
nineteenth century, J. Geophys. Res., 108, 4407, https://doi.org/10.1029/2002JD002670,
2003.
Sarmiento, J. L. and Gruber, N.: Ocean Biogeochemical Dynamics,
Princeton University Press, Princeton, NJ, USA, 2006.
Siegel, D. A., Doney, S. C., and Yoder, J. A.: The North Atlantic spring
phytoplankton bloom and Sverdrup's critical depth hypothesis, Science, 296,
730–733, 2002.
Siegel, D. A., Maritorena, S., Nelson, N. B., and Behrenfeld, M. J.:
Independence and interdependencies among global ocean color properties:
Reassessing the bio-optical assumption, J. Geophys. Res., 110, C07011,
https://doi.org/10.1029/2004JC002527, 2005.
Sverdrup, H. U.: On conditions for the vernal bloom of phytoplankton, J.
Cons. Perm. Int. Explor. Mer., 18, 287–295, 1953.
Taylor, J. R. and Ferrari, R.: Ocean fronts trigger high latitude
phytoplankton blooms, Geophys. Res. Lett., 38, L23601, https://doi.org/10.1029/2011GL049312, 2011.
Ullman, D. J., McKinley, G. A., Bennington, V., and Dutkiewicz, S.: Trends in
the North Atlantic carbon sink: 1992–2006, Global Biogeochem. Cy., 23,
GB4011, https://doi.org/10.1029/2008GB003383, 2009.
Våge, K., Pickart, R. S., Thierry, V., Reverdin, G., Lee, C. M., Petrie,
B., Agnew, T. A., Wong, A., and Ribergaard, M. H.: Surprising return of deep
convection to the subpolar North Atlantic Ocean in winter 2007–2008, Nat.
Geosci., 2, 67–72, 2008.
Westberry, T., Behrenfeld, M. J., Siegel, D. A., and Boss, E. S.: Carbon-based
primary productivity modeling with vertically resolved photoacclimation.
Global Biogeochem. Cy., 22, GB2024, https://doi.org/10.1029/2007GB003078, 2008.
Williams, R. G. and Follows, M. J.: The Ekman transfer of nutrients and
maintenance of new production over the North Atlantic, Deep-Sea Res. Pt. I, 45,
461–489, 1998.
Williams, R. G., McLaren, A. J., and Follows, M. J.: Estimating the convective
supply of nitrate and implied variability in export production over the
North Atlantic, Global Biogeochem. Cy., 14, 1299–1313, 2000.
Williams, R. G., Roussenov, V., and Follows, M. J.: Nutrient streams and their
induction into the mixed layer, Global Biogeochem. Cy., 20, GB1016,
https://doi.org/10.1029/2005GB002586, 2006.
Williams, R. G., Roussenov, V., Smith, D., and Lozier, M. S.: Decadal evolution
of ocean thermal anomalies in the North Atlantic: The effects of ekman,
overturning, and horizontal transport, J. Climate, 27, 698–719,
2014.
Yoder, J. A. and Kennelly, M. A.: Seasonal and ENSO variability in global
ocean phytoplankton chlorophyll derived from 4 years of SeaWiFS
measurements, Global Biogeochem. Cy., 17, 1112, https://doi.org/10.1029/2002GB001942,
2003.
Short summary
Phytoplankton biomass changed significantly in the North Atlantic north of 40° N over 1998–2007. With a physical-ecosystem model, we show that biomass increases in the northwest are due to reduced vertical mixing that partially relieves light limitation of phytoplankton. To the east, these circulation changes lead to fewer nutrients being supplied horizontally from the west. Relationships between these biomass variations and atmosphere and ocean physics are not straightforward.
Phytoplankton biomass changed significantly in the North Atlantic north of 40° N over 1998–2007....
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