Articles | Volume 15, issue 21
https://doi.org/10.5194/bg-15-6461-2018
© 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-15-6461-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Evaluation of the seasonal formation of subsurface negative preformed nitrate anomalies in the subtropical North Pacific and North Atlantic
Robert T. Letscher
CORRESPONDING AUTHOR
Earth Sciences and Ocean Process Analysis Laboratory, University of New
Hampshire, Durham, NH 03824, USA
Tracy A. Villareal
Department of Marine Science and Marine Science Institute, The University
of Texas at Austin, Port Aransas, Austin, TX 78382, USA
Related authors
R. T. Letscher, J. K. Moore, Y.-C. Teng, and F. Primeau
Biogeosciences, 12, 209–221, https://doi.org/10.5194/bg-12-209-2015, https://doi.org/10.5194/bg-12-209-2015, 2015
Short summary
Short summary
Marine DOM is known to exhibit stoichiometry depleted in N and P compared with POM, suggesting variable production and remineralization stoichiometry for C, N, and P within marine DOM cycling. We utilize marine DOM observations and an inverse tracer modeling framework to optimize DOM cycling parameters for the BEC biogeochemistry ocean model of the CESM, finding a variable stoichiometry with faster turnover of P > N > C superior to the commonly assumed Redfield stoichiometry for marine DOM.
Nicole J. Bale, Tracy A. Villareal, Ellen C. Hopmans, Corina P. D. Brussaard, Marc Besseling, Denise Dorhout, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 15, 1229–1241, https://doi.org/10.5194/bg-15-1229-2018, https://doi.org/10.5194/bg-15-1229-2018, 2018
Short summary
Short summary
Associations between diatoms and N-fixing cyanobacteria (diatom–diazotroph associations, DDAs) play an important role in the N cycle of the tropical North Atlantic. Heterocysts are the site of N fixation and contain unique glycolipids. We measured these glycolipids in the water column and surface sediment from the tropical North Atlantic. We found a significant correlation between the concentration of glycolipid and of DDAs, strengthening their application as biomarkers.
R. T. Letscher, J. K. Moore, Y.-C. Teng, and F. Primeau
Biogeosciences, 12, 209–221, https://doi.org/10.5194/bg-12-209-2015, https://doi.org/10.5194/bg-12-209-2015, 2015
Short summary
Short summary
Marine DOM is known to exhibit stoichiometry depleted in N and P compared with POM, suggesting variable production and remineralization stoichiometry for C, N, and P within marine DOM cycling. We utilize marine DOM observations and an inverse tracer modeling framework to optimize DOM cycling parameters for the BEC biogeochemistry ocean model of the CESM, finding a variable stoichiometry with faster turnover of P > N > C superior to the commonly assumed Redfield stoichiometry for marine DOM.
Related subject area
Biogeochemistry: Open Ocean
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
Model estimates of metazoans' contributions to the biological carbon pump
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
The representation of alkalinity and the carbonate pump from CMIP5 to CMIP6 ESMs and implications for the ocean carbon cycle
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
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
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
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 Andre W. Visser
EGUsphere, https://doi.org/10.5194/egusphere-2022-1227, https://doi.org/10.5194/egusphere-2022-1227, 2022
Short summary
Short summary
Large numbers of marine organisms such as zooplankton and fish perform daily vertical migration between the surface (during nighttime) and the depths (during 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 draw-down and storage, and show that fish are important to the biological carbon pump
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
Short summary
Short summary
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
Short summary
Short summary
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.
Alban Planchat, Lester Kwiatkwoski, 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
EGUsphere, https://doi.org/10.5194/egusphere-2022-1041, https://doi.org/10.5194/egusphere-2022-1041, 2022
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
Decadal trends of fugacity of CO2 (fCO2), total alkalinity (AT), total carbon (CT) and pH in surface waters are investigated in different domains of the southern Indian Ocean (45°S–57°S) from ongoing and station observations regularly conducted in summer over the period 1998–2019. The fCO2 increase and pH decrease are mainly driven by anthropogenic CO2 estimated just below the summer mixed layer, as well as by a warming south of the polar front or in the fertilized waters near Kerguelen Island.
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
Short summary
Short summary
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
Short summary
Short summary
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
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.
Cited articles
Abell, J., Emerson, S., and Renaud, P.: Distributions of TOP, TON and TOC in
the North Pacific subtropical gyre: Implications for nutrient supply in the
surface ocean and remineralization in the upper thermocline, J. Marine
Research, 58, 203–222, 2000.
Abell, J., Emerson, S., and Keil, R. G.: Using preformed nitrate to infer
decadal changes in DOM remineralization in the subtropical North Pacific,
Global Biogeochem. Cy., 19, GB1008, https://doi.org/10.1029/2004GB002285, 2005.
Ascani, F., Richards, K. J., Firing, E., Grant, S., Johnson, K. S., Jia, Y.,
Lukas, R., and Karl, D. M.: Physical and biological controls of nitrate
concentrations in the upper subtropical North Pacific Ocean, Deep-Sea Res.
Pt. II, 93, 119–134, 2013.
Alldredge, A. L. and Silver, M. W.: Abundance and production rates of
floating diatom mats (Rhizosolenia castracanei and
Rhizosolenia imbricata var. shrubsolei) in the eastern
Pacific Ocean, Mar. Biol., 66, 83–88, 1982.
Alldredge, A. L., Passow, U., and Logan, B. E.: The abundance and
significance of a class of large, transparent organic particles in the ocean,
Deep-Sea Res. Pt. I, 40, 1131–1140, 1993.
Ammerman, J. W., Hood, R. R., Case, D. A., and Cotner, J. B.: Phosphorus
deficiency in the Atlantic: An emerging paradigm in oceanography, Eos T. Am.
Geophys. Un., 84, 165–170, 2003.
Anderson, L. A.: On the hydrogen and oxygen content of marine phytoplankton,
Deep-Sea Res. Pt. 1, 42, 1675–1680, 1995.
Anderson, L. A. and Sarmiento, J. L.: Redfield ratios of remineralization
determined by nutrient data analysis, Global Biogeochem. Cy., 8, 65–80,
1994.
Azetsu-Scott, K. and Passow, U.: Ascending marine particles: Significance of
transparent exopolymer particles (TEP) in the upper ocean, Limnol. Oceanogr.,
49, 741–748, 2004.
Ballek, R. W. and Swift, E.: Nutrient-and light-mediated buoyancy control of
the oceanic non-motile dinoflagellate Pyrocystis noctiluca Murray ex
Haeckel (1890), J. Exp. Mar. Biol. Ecol., 101, 175–192, 1986.
Bauerfeind, E.: Primary production and phytoplankton biomass in the
equatorial region of the Atlantic at 22∘ west, Oceanological Acta,
Proceedings of the International Symposium on Equatorial Vertical Motion,
131–136, 1987.
Belyayeva, T. V.: Range and numbers of diatoms in the genus
Ethmodiscus Castr. in the Pacific plankton and sediments,
Oceanology, Academy of Science, USSR, Eos T. Am. Geophys. Un., 8, 79–85,
1968.
Belyayeva, T. V.: Abundance of Ethmodiscus in Pacific plankton,
Oceanology, Academy of Science, USSR, Eos T. Am. Geophys. Un., 10, 672–675,
1970.
Booth, B. C.: Vernal phytoplankton community in the eastern subarctic
Pacific: Predominant species, Proceedings of the Sixth International Diatom Symposium, edited by: Ross, R., Otto Koeltz, Koenigstein, Germany, 339–358, 1980.
Broecker, W. S.: “NO” A conservative water-mass tracer, Earth Planet. Sc.
Lett., 23, 100–107, 1974.
Carlson, C. A., Ducklow, H. W., and Sleeter, T. D.: Stocks and dynamics of
bacterioplankton in the northwestern Sargasso Sea, Deep-Sea Res. Pt. II, 43,
491–515, 1996.
Caron, D. A., Lim, E. L., Sanders, R. W., Dennett, M. R., and Berninger, U.
G.: Responses of bacterioplankton and phytoplankton to organic carbon and
inorganic nutrient addition in two oceanic ecosystems, Aquat. Microb. Ecol.,
22, 175–184, 2000.
Carpenter, E. J., Harbison, R. G., Madin, L. P., Swanberg, N. R., Biggs, D.
C., Hulburt, E. M., McAlister, V. L., and McCarthy, J. J.:
Rhizosolenia Mats, Limnol. Oceanogr., 22, 739–741, 1977.
Church, M. J., Ducklow, H. W., and Karl, D. M.: Light dependence of [3H]
leucine incorporation in the oligotrophic North Pacific Ocean, Appl. Environ.
Microbiol., 70, 4079–4087, 2004.
Cisternas-Novoa, C., Lee, C., and Engel, A.: Transparent exopolymer particles
(TEP) and Coomassie stainable particles (CSP): Differences between their
origin and vertical distributions in the ocean, Mar. Chem., 175, 56–71,
2015.
Cleve, P.: Seasonal distribution of Atlantic plankton organisms, D. R.
Bonniers, Göteborg, 368 pp., 1900.
Cotner, J. B., Ammerman, J. W., Peele, E. R., and Bentzen, E.:
Phosphorus-limited bacterioplankton growth in the Sargasso Sea, Aquat.
Microb. Ecol., 13, 141–149, 1997.
Cowen, J. P. and Holloway, C. F.: Structural and chemical analysis of marine
aggregates: in-situ macrophotography and laser confocal and electron
microscopy, Mar. Biol., 126, 163–174, 1996.
Cullen, J. J.: Diel vertical migration by dinoflagellates: roles of
carbohydrate metabolism and behavioral flexibility, in: Migration: mechanisms
and adaptive significance, edited by: Rankin, M. A., Marine Science
Institute, Port Aransas, 135–152, 1985.
Darwin, C.: The Voyage of the Beagle, Natural History Library edition (1962),
edited by: Engle, L., Doubleday, New York, 524 pp., 1860.
DeVries, T. and Deutsch, C.: Large-scale variations in the stoichiometry of
marine organic matter respiration, Nat. Geosci., 7, 890–894, 2014.
Doney, S. C. and Bullister, J. L.: A chlorofluorocarbon section in the
eastern North Atlantic, Deep-Sea Res. Pt. I, 39, 1857–1883, 1992.
Emerson, S.: Annual net community production and the biological carbon flux
in the ocean, Global Biogeochem. Cy., 28, 14–28, 2014.
Emerson, S., Quay, P., Karl, D., Winn, C., Tupas, L., and Landry, M.:
Experimental determination of the organic carbon flux from open-ocean surface
waters, Nature, 389, 951–954, 1997.
Engel, A.: Distribution of transparent exopolymer particles (TEP) in the
northeast Atlantic Ocean and their potential significance for aggregation
processes, Deep-Sea Res. Pt. I, 51, 83–92, 2004.
Eppley, R. W., Holm-Hansen, O., and Strickland, J. D. H.: Some observations
on the vertical migration of dinoflagellates, J. Phycol., 4, 333–340, 1968.
Fawcett, S. E., Lomas, M. W., Casey, J. R., Ward, B. B., and Sigman, D. M.:
Assimilation of upwelled nitrate by small eukaryotes in the Sargasso Sea,
Nat. Geosci., 4, 717–722, 2011.
Fraga, F.: Phytoplanktonic biomass synthesis: application to deviations from
Redfield stoichiometry, Sci. Mar., 65, 153–169, 2001.
Fraga, F., Pérez, F. F., Figueiras, F. G., and Rios, A. F.:
Stoichiometric variations of N, P, C and O2 during a
Gymnodinium catenatum red tide and their interpretation, Mar. Ecol.
Prog. Ser., 87, 123–134, 1992.
Fraga, F., Rios, A. F., Pérez, F. F., Estrada, M., and Marrase, C.:
Effect of upwelling pulses on excess carbohydrate synthesis as deduced from
nutrient, carbon dioxide, and oxygen profiles, Mar. Ecol. Prog. Ser., 189,
65–75, 1999.
Ganf, G. G. and Oliver, R. L.: Vertical separation of light and available
nutrients as a factor causing replacement of green algae by blue-green algae
in the plankton of a stratified lake, J. Ecol., 829–844, 1982.
Garcia, H. E., Locarnini, R. A., Boyer, T. P., Antonov, J. I., Baranova, O.
K., Zweng, M. M., Reagan, J. R., and Johnson, D. R.: World Ocean Atlas 2013,
in: Dissolved Oxygen, Apparent Oxygen Utilization, and Oxygen Saturation,
vol. 3, edited by: Levitus, S. and Mishonov, A.. NOAA Atlas NESDIS 75,
27 pp., 2014a.
Garcia, H. E., Locarnini, R. A., Boyer, T. P., Antonov, J. I., Baranova, O.
K., Zweng, M. M., Reagan, J. R., and Johnson, D. R.: World Ocean Atlas 2013,
in: Dissolved Inorganic Nutrients (phosphate, nitrate, silicate), vol. 4,
edited by: Levitus, S. and Mishonov, A., NOAA Atlas NESDIS 76, 25 pp., 2014b.
Goncalves da Silva, M. G.: Diatom (Bacillariophyceae) distribution in the
continental shelf of Pernambuco (Brazil), Trab. Oceanogr. Univ. Fed.
Pernambuco., 17, 7–46, 1982 (in Spanish).
Gruber, N., Keeling, C. D., and Stocker, T. F.: Carbon-13 constraints on the
seasonal inorganic carbon budget at the BATS site in the northwestern
Sargasso Sea, Deep-Sea Res. Pt. I, 45, 673–717, 1998.
Gruber, N., Keeling, C. D., and Bates, N. R.: Interannual variability in the
North Atlantic Ocean carbon sink, Science, 298, 2374–2378, 2002.
Guidi, L., Calil, P. H. R., Duhamel, S., Bjoerkman, K. M., Doney, S. C.,
Jackson, G. A., Li, B., Church, M. J., Tozzi, S., Kolber, Z. S., Richards, K.
J., Fong, A. A., Letelier, R. M., Gorsky, G., Stemmann, L., and Karl, D. M.:
Does eddy-eddy interaction control surface phytoplankton distribution and
carbon export in the North Pacific Subtropical Gyre?, J. Geophys.
Res.-Biogeosci., 117, G02024, https://doi.org/10.1029/2012jg001984, 2012.
Gundersen, K., Heldal, M., Norland, S., Purdie, D. A., and Knap, A. H.:
Elemental C, N, and P cell content of individual bacteria collected at the
Bermuda Atlantic Time-series Study (BATS) site, Limnol. Oceanogr., 47,
1525–1530, 2002.
Hamanaka, J., Tanoue, E., Hama, T., and Handa, N.: Production and export of
particulate fatty acids, carbohydrates and combined amino acids in the
euphotic zone, Mar. Chem., 77, 55–69, 2002.
Hansell, D. A. and Carlson, C. A.: Biogeochemistry of total organic carbon
and nitrogen in the Sargasso Sea: control by convective overturn, Deep-Sea
Res. Pt. II, 48, 1649–1667, 2001.
Hasle, G. R.: Phototactic vertical migration in marine dinoflagellates,
Oikos, 2, 162–175, 1950.
Jenkins, W. J. and Doney, S. C.: The subtropical nutrient spiral, Global
Biogeochem. Cy., 17, 1110, https://doi.org/10.1029/2003GB002085, 2003.
Jenkins, W. J. and Goldman, J. C.: Seasonal oxygen cycling and primary
production in the Sargasso Sea, J. Mar. Res., 43, 465–491, 1985.
Johnson, K. S., Riser, S. C., and Karl, D. M.: Nitrate supply from deep to
near-surface waters of the North Pacific subtropical gyre, Nature, 465,
1062–1065, 2010.
Joseph, L., Villareal, T. A., and Lipschultz, F.: A high sensitivity nitrate
reductase assay and its application to vertically migrating Rhizosolenia
mats, Aquat. Microb. Ecol., 12, 95–104, 1997.
Kahn, H. and Swift, E.: Positive buoyancy through ionic control in the
nonmotile marine dinoflagellate Pyrocystis noctiluca Murray ex
Schuett, Limnol. Oceanogr., 23, 649–658, 1978.
Keeling, C. D., Brix, H., and Gruber, N.: Seasonal and long-term dynamics of
the upper ocean carbon cycle at Station ALOHA near Hawaii, Global Biogeochem.
Cy., 18, GB4006, https://doi.org/10.1029/2004GB002227, 2004.
Kirchman, D. L.: The uptake of inorganic nutrients by heterotrophic bacteria,
Microb. Ecol., 28, 255–271, 1994.
Letscher, R. T. and Moore, J. K.: Preferential remineralization of dissolved
organic phosphorus and non-Redfield DOM dynamics in the global ocean: Impacts
on marine productivity, nitrogen fixation, and carbon export, Global
Biogeochem. Cy., 29, 325–340, 2015.
Letscher, R. T. and Villareal, T. A: Residual preformed nitrate and
phosphate at Station ALOHA and BATS, PANGAEA,
https://doi.pangaea.de/10.1594/PANGAEA.895472, 2018.
Letscher, R. T., Knapp, A. N., James, A. K., Carlson, C. A., Santoro, A. E.,
and Hansell, D. A.: Microbial community composition and nitrogen availability
influence DOC remineralization in the South Pacific Gyre, Mar. Chem., 177,
325–334, 2015.
Letscher, R. T., Primeau, F., and Moore, J. K.: Nutrient budgets in the
subtropical ocean gyres dominated by lateral transport, Nat. Geosci., 9,
815–819, 2016.
Long, R. A. and Azam, F.: Abundant protein-containing particles in the sea,
Aquat. Microb. Ecol., 10, 213–221, 1996.
Mari, X., Passow, U., Migon, C., Burd, A. B., and Legendre, L.: Transparent
exopolymer particles: Effects on carbon cycling in the ocean, Progr.
Oceanogr., 151, 13–37, 2017.
Martin, J. H., Knauer, G. A., Karl, D. M., and Broenkow, W. W.: VERTEX:
carbon cycling in the northeast Pacific, Deep-Sea Res. Pt. A, 34, 267–285,
1987.
Martinez, L. A.: Nitrogen fixation by floating diatom mats: a source of new
nitrogen to oligotrophic ocean waters, Biology, University of California,
Santa Cruz, 23 pp., 1982.
Martiny, A. C., Pham, C. T., Primeau, F. W., Vrugt, J. A., Moore, J. K.,
Levin, S. A., and Lomas, M. W.: Strong latitudinal patterns in the elemental
ratios of marine plankton and organic matter, Nat. Geosci., 6, 279–283,
2013.
Michaels, A. F., Bates, N. R., Buesseler, K. O., Carlson, C. A., and Knap, A.
H.: Carbon-cycle imbalances in the Sargasso Sea, Nature, 372, 537–540, 1994.
Mikkelsen, N.: On the origin of Ethmodiscus ooze, Mar.
Micropaleontol., 2, 35–46, 10.1016/0377-8398(77)90004-4, 1977.
Moore, J. K. and Villareal, T. A.: Size-ascent rate relationships in
positively buoyant marine diatoms, Limnol. Oceanogr., 41, 1514–1520, 1996.
Moore, J. K., Doney, S. C., and Lindsay, K.: Upper ocean ecosystem dynamics
and iron cycling in a global three-dimensional model, Global Biogeochem. Cy.,
18, GB4028, https://doi.org/10.1029/2004GB002220 , 2004.
Navarro, G. and Ruiz, J.: Hysteresis conditions the vertical position of deep
chlorophyll maximum in the temperate ocean, Global Biogeochem. Cy., 27,
1013–1022, 2013.
Olsen, A., Key, R. M., van Heuven, S., Lauvset, S. K., Velo, A., Lin, X.,
Schirnick, C., Kozyr, A., Tanhua, T., Hoppema, M., Jutterström, S.,
Steinfeldt, R., Jeansson, E., Ishii, M., Pérez, F. F., and Suzuki, T.:
The Global Ocean Data Analysis Project version 2 (GLODAPv2) – an internally
consistent data product for the world ocean, Earth Syst. Sci. Data, 8,
297–323, https://doi.org/10.5194/essd-8-297-2016, 2016.
Paulmier, A., Kriest, I., and Oschlies, A.: Stoichiometries of
remineralisation and denitrification in global biogeochemical ocean models,
Biogeosciences, 6, 923–935, https://doi.org/10.5194/bg-6-923-2009, 2009.
Pilskaln, C. H., Villareal, T. A., Dennett, M., Darkangelo-Wood, C., and
Meadows, G.: High concentrations of marine snow and diatom algal mats in the
North Pacific Subtropical Gyre: Implications for carbon and nitrogen cycles
in the oligotrophic ocean, Deep-Sea Res. Pt. I, 52, 2315–2332, 2005.
Platt, T., Harrison, W. G., Lewis, M. R., Li, W. K., Sathyendranath, S.,
Smith, R. E., and Vezina, A. F.: Biological production of the oceans: the
case for a consensus, Marine Ecology Progress Series, 77–88, 1989.
Ricard, M.: Observations sur les diatomées marines du genre
Ethmodiscus Castr., Rev. Algol. N.S.O, 10, 56–73, 1970.
Richardson, T. L., Ciotti, A. M., Cullen, J. J., and Villareal, T. A.:
Physiological and optical properties of Rhizosolenia formosa
(Bacillariophyceae) in the context of open-ocean vertical migration, J.
Phycol., 32, 741–757, 1996.
Richardson, T. L., Cullen, J. J., Kelley, D. E., and Lewis, M. R.: Potential
contributions of vertically migrating Rhizosolenia to nutrient cycling and
new production in the open ocean, J. Plankton Re., 20, 219–241, 1998.
Ricker, W. E.: Linear regressions in fishery research, J. Fish Res. Board
Can., 30, 409–434, 1973.
Rivkin, R. B. and Anderson, M. R.: Inorganic nutrient limitation of oceanic
bacterioplankton, Limnol. Oceanogr., 42, 730–740, 1997.
Rivkin, R. B., Swift, E., Biggley, W. H., and Voytek, M. A.: Growth and
carbon uptake by natural populations of oceanic dinoflagellates
Pyrocystis noctiluca and Pyrocystis fusiformis,
Deep-Sea Res. Pt. A, 31, 353–367, 1984.
Semina, H. J. and Levashova, S. S.: The biogeography of tropical
phytoplankton species in the Pacific Ocean, Int. Rev. Gesamten Hydrobiol.,
78, 243–262, 1993.
Semina, H. J., Belyayeva, T. V., Zernova, V. V., MovChan, O. A., Sanina, L.
V., Sukhanova, I. N., and Tarkhova, I. A.: Distribution of indicator species
of planktonic algae in the World Ocean, Oceanology, 17, 573–579, 1977.
Shipe, R. F., Brzezinski, M. A., Pilskaln, C., and Villareal, T. A.:
Rhizosolenia mats: An overlooked source of silica production in the
open sea, Limnol. Oceanogr., 44, 1282–1292, 1999.
Shulenberger, E. and Reid, J. L.: The Pacific shallow oxygen maximum, deep
chlorophyll maximum, and primary productivity, reconsidered, Deep-Sea Res.
Pt. A, 28, 901–919, 1981.
Singler, H. R. and Villareal, T. A.: Nitrogen inputs into the euphotic zone
by vertically migrating Rhizosolenia mats, J. Plankton Re., 27,
545–556, 2005.
Steemann Nielsen, E.: Über die vertikale Verbreitung der Phytoplanktonten
im Meere, Internationale Revue der gesamten Hydrobiologie und Hydrographie,
38, 421–440, https://doi.org/10.1002/iroh.19390380124, 1939.
Sukhanova, I. N.: Vertical distribution of some peridinians in the equatorial
Pacific Ocean, in: Life activities of pelagic communities in the ocean,
edited by: Vinogradov, M. E., Israeli Program Scientific Translation,
Jerusalem, 210–217, 1973.
Sukhanova, I. N. and Rudyakov, Y. A.: Population composition and vertical
distribution of Pyrocystis pseudonoctiluca (W. Thomson) in
the western equatorial Pacific, in: Life activities of pelagic communities in
the ocean, edited by: Vinogradov, M. E., Israeli Program Scientific
Translation, Jerusalem, 218–228, 1973.
Swift, E.: The marine diatom Ethmodiscus rex: its morphology and
occurrence in the plankton of the Sargasso Sea, J. Phycol., 2, 456–460,
1973.
Swift, E., Biggley, W. H., and Seliger, H. H.: Species of oceanic
dinoflagellates in genera Dissodinium and Pyrocystis:
Interclonal and interspecific comparisons of coloar and photon yield of
bioluminscence, J. Phycol., 9, 420–426,
https://doi.org/10.1111/j.0022-3646.1973.00420.x, 1973.
Swift, E., Stuart, M., and Meunier, V.: The in situ growth rates of
some deep-living oceanic dinoflagellates: Pyrocystis fusiformis and
Pyrocystis noctiluca, Limnol. Oceanogr., 21, 418–426, 1976.
Swift, E., Meunier, V. A., Biggley, W. H., Hoarau, J., and Barras, H.:
Factors affecting bioluminescence capacity in oceanic dinoflagellates, in:
Bioluminescence: current perspectives, edited by: Nealson, K. H., Burgess
Publishing Co., Minneapolis, 95–106, 1981.
Takahashi, T., Broecker, W. S., and Langer, S.: Redfield ratio based on
chemical data from isopycnal surfaces, J. Geophys. Res.-Oceans, 90,
6907–6924, 1985.
Teng, Y. C., Primeau, F. W., Moore, J. K., Lomas, M. W., and Martiny, A. C.:
Global-scale variations of the ratios of carbon to phosphorus in exported
marine organic matter, Nat. Geosci., 7, 895–898, 2014.
Toggweiler, J. R.: Carbon overconsumption, Nature, 363, 210–211, 1993.
Toggweiler, J. R.: Vanishing in Bermuda, Nature, 372, 505–506, 1994.
Trujillo-Ortiz, A. and Hernandez-Walls, R.: gmregress: Geometric Mean
Regression (Reduced Major Axis Regression), A MATLAB file, available at:
http://www.mathworks.com/matlabcentral/fileexchange/27918-gmregress (last access: 12 December 2017), 2010.
Venrick, E. L.: The distribution and ecology of oceanic diatoms in the North
Pacific, PhD, University of California, San Diego, 684 pp., 1969.
Villareal, T. A.: Abundance of the giant diatom Ethmodiscus in the
southwest Atlantic Ocean and central Pacific gyre, Diatom Research, 8,
171–177, 1993.
Villareal, T. A.: Single-cell pulse amplitude modulation fluorescence
measurements of the giant diatom Ethmodiscus (Bacillariophyceae), J. Phycol.,
40, 1052–1061, https://doi.org/10.1111/j.1529-8817.2004.03208.x, 2004.
Villareal, T. A. and Carpenter, E. J.: Nitrogen-fixation, suspension
characteristics and chemical composition of Rhizosolenia mats in the
central North Pacific Gyre, Biol. Oceanogr., 6, 327–345, 1989.
Villareal, T. A. and Carpenter, E. J.: Chemical composition and
photosynthetic characteristics of Ethmodiscus rex
(Bacillariophyceae): Evidence for vertical migration, J. Phycol., 30, 1–8,
1994.
Villareal, T. A. and Lipschultz, F.: Internal nitrate concentrations in
single cells of large phytoplankton from the Sargasso Sea, J. Phycol., 31,
689–696, 1995.
Villareal, T. A., Altabet, M. A., and Culver-Rymsza, K.: Nitrogen transport
by vertically migrating diatom mats in the North Pacific Ocean, Nature, 363,
709–712, 1993.
Villareal, T. A., Woods, S., Moore, J. K., and Culver-Rymsza, K.: Vertical
migration of Rhizosolenia mats and their significance to NO fluxes in
the central North Pacific gyre, J. Plankton Re., 18, 1103–1121, 1996.
Villareal, T. A., Joseph, L., Brzezinski, M. A., Shipe, R. F., Lipschultz,
F., and Altabet, M. A.: Biological and chemical characteristics of the giant
diatom Ethmodiscus (Bacillariophyceae) in the central North Pacific
gyre, J. Phycol., 35, 896–902, 1999a.
Villareal, T. A., Pilskaln, C., Brzezinski, M., Lipschultz, F., Dennett, M.,
and Gardner, G. B.: Upward transport of oceanic nitrate by migrating diatom
mats, Nature, 397, 423–425, 1999b.
Villareal, T. A., McKay, R. M. L., Al-Rshaidat, M. M. D., Boyanapalli, R.,
and Sherrell, R. M.: Compositional and fluorescence characteristics of the
giant diatom Ethmodiscus along a 3000 km transect (28∘ N)
in the central North Pacific gyre, Deep-Sea Res. Pt. I, 54 1273–1288, 2007.
Villareal, T. A., Pilskaln, C. H., Montoya, J. P., and Dennett, M.: Upward
nitrate transport by phytoplankton in oceanic waters: balancing nutrient
budgets in oligotrophic seas, PeerJ, 2, e302, https://doi.org/10.7717/peerj.302, 2014.
Walker, S. J., Weiss, R. F., and Salameh, P. K.: Reconstructed histories of
the annual mean atmospheric mole fractions for the halocarbons CFC-11,
CFC-12, CFC-113, and carbon tetrachloride, J. Geophys. Res.-Oceans, 105,
14285–14296, 2000.
Wallich, G. C.: On microscopic objects collected in India, T. Microscop. Soc.
London, 6, 81–87, 1858.
Warner, M. J. and Weiss, R. F.: Solubilities of chlorofluorocarbons 11 and 12
in water and seawater, Deep-Sea Res. Pt. A, 32, 1485–1497, 1985.
Wiebe, P. H., Remsen, C. C., and Vaccaro, R. F.: Halosphaera viridis
in the Mediterranean Sea: size range, vertical distribution, and potential
energy source for deep-sea benthos, in: Deep Sea Research and Oceanographic
Abstracts, Elsevier, 21, 657–667, 1974.
Williams, P. J. L. B., Quay, P. D., Westberry, T. K., and Behrenfeld, M. J.:
The oligotrophic ocean is autotrophic, Annu. Rev. Mar. Sci., 5, 535–549,
2013.
Woods, S. and Villareal, T. A.: Intracellular ion concentrations and cell sap
density in positively buoyant oceanic phytoplankton, Nova Hedwigia Beihefte,
133, 131–145, 2008.
Wurl, O., Miller, L., Röttgers, R., and Vagle, S.: The distribution and
fate of surface-active substances in the sea-surface microlayer and water
column, Mar. Chem., 115, 1–9, 2009.
Wurl, O., Miller, L., and Vagle, S.: Production and fate of transparent
exopolymer particles in the ocean, J. Geophys. Res.-Oceans, 116, C00H13,
https://doi.org/10.1029/2011JC007342, 2011.
Zweifel, U. L., Norrman, B., and Hagstrom, A.: Consumption of dissolved
organic carbon by marine bacteria and demand for inorganic nutrients, Mar.
Ecol. Prog. Ser., 101, 23–32, 1993.
Short summary
The formation rates of oxygen to nitrogen anomalies in the subtropical North Pacific and North Atlantic were estimated from time series data. We find that vertically migrating phytoplankton, which traverse ~ 100–150 m in the upper ocean over days to acquire nutrients from waters at depth and return to the surface for photosynthesis, likely explain the observed anomalies and help sustain surface ocean productivity and the biological pump throughout the annual cycle in the subtropical ocean.
The formation rates of oxygen to nitrogen anomalies in the subtropical North Pacific and North...
Altmetrics
Final-revised paper
Preprint