Articles | Volume 15, issue 14
https://doi.org/10.5194/bg-15-4431-2018
© 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-15-4431-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
19 Jul 2018
Research article |
| 19 Jul 2018
| 19 Jul 2018
Impact of decadal reversals of the north Ionian circulation on phytoplankton phenology
Héloise Lavigne
CORRESPONDING AUTHOR
Royal Belgian Institute of Natural Sciences, Operational Directorate
Natural Environment, Gulledelle 100, 1200 Brussels, Belgium
Giuseppe Civitarese
Istituto Nazionale di Oceanografia e di Geofisica Sperimentale – OGS,
Dip. di Oceanografia, Borgo Grotta Gigante 42/c, 34010 Sgonico (Trieste),
Italy
Miroslav Gačić
Istituto Nazionale di Oceanografia e di Geofisica Sperimentale – OGS,
Dip. di Oceanografia, Borgo Grotta Gigante 42/c, 34010 Sgonico (Trieste),
Italy
Fabrizio D'Ortenzio
Laboratoire d'Oceanographie de Villefranche, Université Pierre et
Marie Curie et CNRS, UMR 7093, Villefranche-sur-Mer, France
Related authors
Héloïse Lavigne, Ana Dogliotti, David Doxaran, Fang Shen, Alexandre Castagna, Matthew Beck, Quinten Vanhellemont, Xuerong Sun, Juan Ignacio Gossn, Pannimpullath Remanan Renosh, Koen Sabbe, Dieter Vansteenwegen, and Kevin Ruddick
Earth Syst. Sci. Data, 14, 4935–4947, https://doi.org/10.5194/essd-14-4935-2022, https://doi.org/10.5194/essd-14-4935-2022, 2022
Short summary
Short summary
Because of the large diversity of case 2 waters and the complexity of light transfer, retrieving main biogeochemical parameters in these waters is still challenging. By providing optical and biogeochemical parameters for 180 sampling stations with turbidity and chlorophyll-a concentration ranging from low to extreme values, the HYPERMAQ dataset will contribute to a better description of marine optics in optically complex water bodies and can help the scientific community to develop algorithms.
Alexandre Castagna, Luz Amadei Martínez, Margarita Bogorad, Ilse Daveloose, Renaat Dasseville, Heidi Melita Dierssen, Matthew Beck, Jonas Mortelmans, Héloïse Lavigne, Ana Dogliotti, David Doxaran, Kevin Ruddick, Wim Vyverman, and Koen Sabbe
Earth Syst. Sci. Data, 14, 2697–2719, https://doi.org/10.5194/essd-14-2697-2022, https://doi.org/10.5194/essd-14-2697-2022, 2022
Short summary
Short summary
Here we describe a dataset of optical measurements paired with the concentration and composition of dissolved and particulate components of water systems in Belgium. Sampling was performed over eight lakes, a coastal lagoon, an estuary, and coastal waters, covering the period of 2017 to 2019. The data cover a broad range of conditions and can be useful for development and evaluation of hyperspectral methods in hydrology optics and remote sensing.
Eva Álvarez, Gianpiero Cossarini, Anna Teruzzi, Jorn Bruggeman, Karsten Bolding, Stefano Ciavatta, Vincenzo Vellucci, Fabrizio D'Ortenzio, David Antoine, and Paolo Lazzari
Biogeosciences, 20, 4591–4624, https://doi.org/10.5194/bg-20-4591-2023, https://doi.org/10.5194/bg-20-4591-2023, 2023
Short summary
Short summary
Chromophoric dissolved organic matter (CDOM) interacts with the ambient light and gives the waters of the Mediterranean Sea their colour. We propose a novel parameterization of the CDOM cycle, whose parameter values have been optimized by using the data of the monitoring site BOUSSOLE. Nutrient and light limitations for locally produced CDOM caused aCDOM(λ) to covary with chlorophyll, while the above-average CDOM concentrations observed at this site were maintained by allochthonous sources.
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
Short summary
Short summary
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.
Héloïse Lavigne, Ana Dogliotti, David Doxaran, Fang Shen, Alexandre Castagna, Matthew Beck, Quinten Vanhellemont, Xuerong Sun, Juan Ignacio Gossn, Pannimpullath Remanan Renosh, Koen Sabbe, Dieter Vansteenwegen, and Kevin Ruddick
Earth Syst. Sci. Data, 14, 4935–4947, https://doi.org/10.5194/essd-14-4935-2022, https://doi.org/10.5194/essd-14-4935-2022, 2022
Short summary
Short summary
Because of the large diversity of case 2 waters and the complexity of light transfer, retrieving main biogeochemical parameters in these waters is still challenging. By providing optical and biogeochemical parameters for 180 sampling stations with turbidity and chlorophyll-a concentration ranging from low to extreme values, the HYPERMAQ dataset will contribute to a better description of marine optics in optically complex water bodies and can help the scientific community to develop algorithms.
Alexandre Castagna, Luz Amadei Martínez, Margarita Bogorad, Ilse Daveloose, Renaat Dasseville, Heidi Melita Dierssen, Matthew Beck, Jonas Mortelmans, Héloïse Lavigne, Ana Dogliotti, David Doxaran, Kevin Ruddick, Wim Vyverman, and Koen Sabbe
Earth Syst. Sci. Data, 14, 2697–2719, https://doi.org/10.5194/essd-14-2697-2022, https://doi.org/10.5194/essd-14-2697-2022, 2022
Short summary
Short summary
Here we describe a dataset of optical measurements paired with the concentration and composition of dissolved and particulate components of water systems in Belgium. Sampling was performed over eight lakes, a coastal lagoon, an estuary, and coastal waters, covering the period of 2017 to 2019. The data cover a broad range of conditions and can be useful for development and evaluation of hyperspectral methods in hydrology optics and remote sensing.
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.
Miroslav Gačić, Laura Ursella, Vedrana Kovačević, Milena Menna, Vlado Malačič, Manuel Bensi, Maria-Eletta Negretti, Vanessa Cardin, Mirko Orlić, Joël Sommeria, Ricardo Viana Barreto, Samuel Viboud, Thomas Valran, Boris Petelin, Giuseppe Siena, and Angelo Rubino
Ocean Sci., 17, 975–996, https://doi.org/10.5194/os-17-975-2021, https://doi.org/10.5194/os-17-975-2021, 2021
Short summary
Short summary
Experiments in rotating tanks can simulate the Earth system and help to represent the real ocean, where rotation plays an important role. We wanted to show the minor importance of the wind in driving the flow in the Ionian Sea. We did this by observing changes in the water current in a rotating tank affected only by the pumping of dense water into the system. The flow variations were similar to those in the real sea, confirming the scarce importance of the wind for the flow in the Ionian Sea.
Paolo Lazzari, Stefano Salon, Elena Terzić, Watson W. Gregg, Fabrizio D'Ortenzio, Vincenzo Vellucci, Emanuele Organelli, and David Antoine
Ocean Sci., 17, 675–697, https://doi.org/10.5194/os-17-675-2021, https://doi.org/10.5194/os-17-675-2021, 2021
Short summary
Short summary
Multispectral optical sensors and models are increasingly adopted to study marine systems. In this work, bio-optical mooring and biogeochemical Argo float optical observations are combined with the Ocean-Atmosphere Spectral Irradiance Model (OASIM) to analyse the variability of sunlight at the sea surface. We show that the model skill in simulating data varies according to the wavelength of light and temporal scale considered and that it is significantly affected by cloud dynamics.
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.
Elena Terzić, Arnau Miró, Paolo Lazzari, Emanuele Organelli, and Fabrizio D'Ortenzio
Biogeosciences Discuss., https://doi.org/10.5194/bg-2020-473, https://doi.org/10.5194/bg-2020-473, 2021
Preprint withdrawn
Short summary
Short summary
This study integrates numerical simulations (using a multi-spectral optical model) with in-situ measurements of floats and remotely sensed observations from satellites. It aims at improving our current understanding of the impact that different constituents (such as pure water, colored dissolved organic matter, detritus and phytoplankton) have on the in-water light propagation.
Cécile Guieu, Fabrizio D'Ortenzio, François Dulac, Vincent Taillandier, Andrea Doglioli, Anne Petrenko, Stéphanie Barrillon, Marc Mallet, Pierre Nabat, and Karine Desboeufs
Biogeosciences, 17, 5563–5585, https://doi.org/10.5194/bg-17-5563-2020, https://doi.org/10.5194/bg-17-5563-2020, 2020
Short summary
Short summary
We describe here the objectives and strategy of the PEACETIME project and cruise, dedicated to dust deposition and its impacts in the Mediterranean Sea. Our strategy to go a step further forward than in previous approaches in understanding these impacts by catching a real deposition event at sea is detailed. We summarize the work performed at sea, the type of data acquired and their valorization in the papers published in the special issue.
Dagmar Hainbucher, Marta Álvarez, Blanca Astray Uceda, Giancarlo Bachi, Vanessa Cardin, Paolo Celentano, Spyros Chaikalis, Maria del Mar Chaves Montero, Giuseppe Civitarese, Noelia M. Fajar, Francois Fripiat, Lennart Gerke, Alexandra Gogou, Elisa F. Guallart, Birte Gülk, Abed El Rahman Hassoun, Nico Lange, Andrea Rochner, Chiara Santinelli, Tobias Steinhoff, Toste Tanhua, Lidia Urbini, Dimitrios Velaoras, Fabian Wolf, and Andreas Welsch
Earth Syst. Sci. Data, 12, 2747–2763, https://doi.org/10.5194/essd-12-2747-2020, https://doi.org/10.5194/essd-12-2747-2020, 2020
Short summary
Short summary
We report on data from an oceanographic cruise in the Mediterranean Sea (MSM72, March 2018). The main objective of the cruise was to contribute to the understanding of long-term changes and trends in physical and biogeochemical parameters, such as the anthropogenic carbon uptake, and further assess the hydrographical situation after the Eastern and Western Mediterranean Transients. Multidisciplinary measurements were conducted on a predominantly
zonal section throughout the Mediterranean Sea.
Vincent Taillandier, Louis Prieur, Fabrizio D'Ortenzio, Maurizio Ribera d'Alcalà, and Elvira Pulido-Villena
Biogeosciences, 17, 3343–3366, https://doi.org/10.5194/bg-17-3343-2020, https://doi.org/10.5194/bg-17-3343-2020, 2020
Short summary
Short summary
This study addresses the role played by vertical diffusion in the nutrient enrichment of the Levantine intermediate waters, a process particularly relevant inside thermohaline staircases. Thanks to a high profiling frequency over a 4-year period, BGC-Argo float observations reveal the temporal continuity of the layering patterns encountered during the cruise PEACETIME and their impact on vertical and lateral transfers of nitrate between the deep reservoir and the surface productive zone.
Elena Terzić, Paolo Lazzari, Emanuele Organelli, Cosimo Solidoro, Stefano Salon, Fabrizio D'Ortenzio, and Pascal Conan
Biogeosciences, 16, 2527–2542, https://doi.org/10.5194/bg-16-2527-2019, https://doi.org/10.5194/bg-16-2527-2019, 2019
Short summary
Short summary
Measuring ecosystem properties in the ocean is a hard business. Recent availability of data from Biogeochemical-Argo floats can help make this task easier. Numerical models can integrate these new data in a coherent picture and can be used to investigate the functioning of ecosystem processes. Our new approach merges experimental information and model capabilities to quantitatively demonstrate the importance of light and water vertical mixing for algae dynamics in the Mediterranean Sea.
Marie Barbieux, Julia Uitz, Bernard Gentili, Orens Pasqueron de Fommervault, Alexandre Mignot, Antoine Poteau, Catherine Schmechtig, Vincent Taillandier, Edouard Leymarie, Christophe Penkerc'h, Fabrizio D'Ortenzio, Hervé Claustre, and Annick Bricaud
Biogeosciences, 16, 1321–1342, https://doi.org/10.5194/bg-16-1321-2019, https://doi.org/10.5194/bg-16-1321-2019, 2019
Short summary
Short summary
As commonly observed in oligotrophic stratified waters, a subsurface (or deep) chlorophyll maximum (SCM) frequently characterizes the vertical distribution of phytoplankton chlorophyll in the Mediterranean Sea. SCMs often result from photoacclimation of the phytoplankton organisms. However they can also result from an actual increase in phytoplankton carbon biomass. Our results also suggest that a variety of intermediate types of SCMs are encountered between these two endmember situations.
Julien Palmiéri, Jean-Claude Dutay, Fabrizio D'Ortenzio, Loïc Houpert, Nicolas Mayot, and Laurent Bopp
Biogeosciences Discuss., https://doi.org/10.5194/bg-2018-423, https://doi.org/10.5194/bg-2018-423, 2018
Manuscript not accepted for further review
Short summary
Short summary
In this model study, we highlight the importance of the subsurface phytoplankton dynamic in the Mediterranean sea. Comparing surface chlorophyll annual cycle to vertically integrated one, we show how important the subsurface phytoplankton community is, throughout the Mediterranean. It shows that surface chlorophyll is incomplete and cannot alone be considered a good proxy of the total phytoplankton biomass. Then, we decrypt some deep chlorophyll maximum mechanisms in the low production area.
Vincent Taillandier, Thibaut Wagener, Fabrizio D'Ortenzio, Nicolas Mayot, Hervé Legoff, Joséphine Ras, Laurent Coppola, Orens Pasqueron de Fommervault, Catherine Schmechtig, Emilie Diamond, Henry Bittig, Dominique Lefevre, Edouard Leymarie, Antoine Poteau, and Louis Prieur
Earth Syst. Sci. Data, 10, 627–641, https://doi.org/10.5194/essd-10-627-2018, https://doi.org/10.5194/essd-10-627-2018, 2018
Short summary
Short summary
We report on data from an oceanographic cruise, covering western, central and eastern parts of the Mediterranean Sea. This cruise was fully dedicated to the maintenance and the metrological verification of a biogeochemical observing system based on a fleet of BGC-Argo floats.
Emanuele Organelli, Marie Barbieux, Hervé Claustre, Catherine Schmechtig, Antoine Poteau, Annick Bricaud, Emmanuel Boss, Nathan Briggs, Giorgio Dall'Olmo, Fabrizio D'Ortenzio, Edouard Leymarie, Antoine Mangin, Grigor Obolensky, Christophe Penkerc'h, Louis Prieur, Collin Roesler, Romain Serra, Julia Uitz, and Xiaogang Xing
Earth Syst. Sci. Data, 9, 861–880, https://doi.org/10.5194/essd-9-861-2017, https://doi.org/10.5194/essd-9-861-2017, 2017
Short summary
Short summary
Autonomous robotic platforms such as Biogeochemical-Argo floats allow observation of the ocean, from the surface to the interior, in a new and systematic way. A fleet of 105 of these platforms have collected several biological, biogeochemical, and optical variables in still unexplored regions. The quality-controlled databases presented here will enable scientists to improve knowledge on the functioning of marine ecosystems and investigate the climatic implications.
Nicolas Mayot, Fabrizio D'Ortenzio, Maurizio Ribera d'Alcalà, Héloïse Lavigne, and Hervé Claustre
Biogeosciences, 13, 1901–1917, https://doi.org/10.5194/bg-13-1901-2016, https://doi.org/10.5194/bg-13-1901-2016, 2016
Short summary
Short summary
The present manuscript provides an analysis of the interannual variability of the phytoplankton seasonality in the Mediterranean Sea, based on 16 years of ocean color data. Important interannual variabilities at regional scale were highlighted and related to environmental factors. Our results demonstrate also that seasonal patterns retrieved from satellite allow to identify the evolution of an oceanic area and to summarize the huge quantity of information that the satellite data offer.
R. Sauzède, H. Lavigne, H. Claustre, J. Uitz, C. Schmechtig, F. D'Ortenzio, C. Guinet, and S. Pesant
Earth Syst. Sci. Data, 7, 261–273, https://doi.org/10.5194/essd-7-261-2015, https://doi.org/10.5194/essd-7-261-2015, 2015
H. Lavigne, F. D'Ortenzio, M. Ribera D'Alcalà, H. Claustre, R. Sauzède, and M. Gacic
Biogeosciences, 12, 5021–5039, https://doi.org/10.5194/bg-12-5021-2015, https://doi.org/10.5194/bg-12-5021-2015, 2015
Short summary
Short summary
The spatiotemporal variability in the vertical distribution of the chlorophyll concentration in the Mediterranean Sea is investigated. Results are based on a large database of fluorescence profiles intercalibrated from ocean color satellite data. They indicate that two types of chlorophyll seasonality coexist in the Mediterranean Sea. The shape of the chlorophyll profile is very dynamic during winter, and the deep chlorophyll maximum is a dominant feature of Mediterranean chlorophyll profile.
C. Guinet, X. Xing, E. Walker, P. Monestiez, S. Marchand, B. Picard, T. Jaud, M. Authier, C. Cotté, A. C. Dragon, E. Diamond, D. Antoine, P. Lovell, S. Blain, F. D'Ortenzio, and H. Claustre
Earth Syst. Sci. Data, 5, 15–29, https://doi.org/10.5194/essd-5-15-2013, https://doi.org/10.5194/essd-5-15-2013, 2013
Related subject area
Biogeochemistry: Open Ocean
Relationships between the concentration of particulate organic nitrogen and the inherent optical properties of seawater in oceanic surface waters
Inadequacies in the representation of sub-seasonal phytoplankton dynamics in Earth system models
Composite model-based estimate of the ocean carbon sink from 1959 to 2022
Phytoplankton community structure in relation to iron and macronutrient fluxes from subsurface waters in the western North Pacific during summer
Intense and localized export of selected marine snow types at eddy edges in the South Atlantic Ocean
Spatial distributions of iron and manganese in surface waters of the Arctic's Laptev and East Siberian seas
Climate-driven shifts in Southern Ocean primary producers and biogeochemistry in CMIP6 models
Ocean acidification trends and carbonate system dynamics across the North Atlantic subpolar gyre water masses during 2009–2019
Pelagic coccolithophore production and dissolution and their impacts on particulate inorganic carbon cycling in the western North Pacific
Marine snow morphology drives sinking and attenuation in the ocean interior
Sedimentary organic matter signature hints at the phytoplankton-driven biological carbon pump in the central Arabian Sea
Hydrological cycle amplification imposes spatial patterns on the climate change response of ocean pH and carbonate chemistry
Assessing the tropical Atlantic biogeochemical processes in the Norwegian Earth System Model
Evolution of oxygen and stratification and their relationship in the North Pacific Ocean in CMIP6 Earth system models
Evaluation of CMIP6 model performance in simulating historical biogeochemistry across the southern South China Sea
Drivers of decadal trends in the ocean carbon sink in the past, present, and future in Earth system models
Anthropogenic carbon storage and its decadal changes in the Atlantic between 1990–2020
Ocean alkalinity enhancement impacts: regrowth of marine microalgae in alkaline mineral concentrations simulating the initial concentrations after ship-based dispersions
An upper mesopelagic zone carbon budget for the subarctic North Pacific
Climatic controls on metabolic constraints in the ocean
Effects of grain size and seawater salinity on magnesium hydroxide dissolution and secondary calcium carbonate precipitation kinetics: implications for ocean alkalinity enhancement
Short-term response of Emiliania huxleyi growth and morphology to abrupt salinity stress
Assessing the impact of CO2-equilibrated ocean alkalinity enhancement on microbial metabolic rates in an oligotrophic system
A time series analysis of transparent exopolymer particle distributions and C:N stoichiometry in the subtropical North Pacific: a key process in net community production and preformed nitrate anomalies?
Phosphomonoesterase and phosphodiesterase activities in the eastern Mediterranean in two contrasting seasonal situations
Net primary production annual maxima in the North Atlantic projected to shift in the 21st century
Testing the influence of light on nitrite cycling in the eastern tropical North Pacific
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
Ocean alkalinity enhancement in an open ocean ecosystem: Biogeochemical responses and carbon storage durability
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
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
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
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
Alain Fumenia, Hubert Loisel, Rick A. Reynolds, and Dariusz Stramski
Biogeosciences, 22, 2461–2484, https://doi.org/10.5194/bg-22-2461-2025, https://doi.org/10.5194/bg-22-2461-2025, 2025
Short summary
Short summary
Particulate organic nitrogen (PON) plays a central role in ocean biogeochemistry, yet limited in situ data hinder a full understanding of PON variability and associated processes. Measurements of optical properties offer an alternative for assessing PON across diverse marine environments. Our analysis reveals strong relationships between PON and optical properties, supporting a promising means to assess PON from optical measurements performed in situ or conducted from remote-sensing platforms.
Madhavan Girijakumari Keerthi, Olivier Aumont, Lester Kwiatkowski, and Marina Levy
Biogeosciences, 22, 2163–2180, https://doi.org/10.5194/bg-22-2163-2025, https://doi.org/10.5194/bg-22-2163-2025, 2025
Short summary
Short summary
We assessed how well climate models replicate sub-seasonal changes in ocean chlorophyll observed by satellites. Models struggle to capture these variations accurately. Some overestimate fluctuations and their impact on annual chlorophyll variability, while others underestimate them. The underestimation is likely due to limited model resolution, while the overestimation may come from internal model oscillations.
Jens Terhaar
Biogeosciences, 22, 1631–1649, https://doi.org/10.5194/bg-22-1631-2025, https://doi.org/10.5194/bg-22-1631-2025, 2025
Short summary
Short summary
The ocean is a major natural carbon sink. Despite its importance, estimates of the ocean carbon sink remain uncertain. Here, I present a hybrid model estimate of the ocean carbon sink from 1959 to 2022. By combining ocean models in hindcast mode and Earth system models, I keep the strength of each approach and remove the respective weaknesses. This composite model estimate is similar in magnitude to the best estimate of the Global Carbon Budget but 70 % less uncertain.
Huailin Deng, Koji Suzuki, Ichiro Yasuda, Hiroshi Ogawa, and Jun Nishioka
Biogeosciences, 22, 1495–1508, https://doi.org/10.5194/bg-22-1495-2025, https://doi.org/10.5194/bg-22-1495-2025, 2025
Short summary
Short summary
Iron (Fe) and nitrate are vital for primary production in the North Pacific. Sedimentary Fe is carried by North Pacific Intermediate Water to the North Pacific, but the nutrient return path and its effect on phytoplankton are unclear. By combining Fe and macronutrient fluxes with phytoplankton composition, this study firstly revealed that Fe supply from the subsurface greatly controls diatom abundance and identified the nutrient return path in the subarctic gyre and Kuroshio–Oyashio transition area.
Alexandre Accardo, Rémi Laxenaire, Alberto Baudena, Sabrina Speich, Rainer Kiko, and Lars Stemmann
Biogeosciences, 22, 1183–1201, https://doi.org/10.5194/bg-22-1183-2025, https://doi.org/10.5194/bg-22-1183-2025, 2025
Short summary
Short summary
The open ocean helps mitigate climate change by storing CO2 via the biological carbon pump (BCP), which involves processes like organic carbon production at the surface and transferring it to the deep ocean via various pathways. By deploying an autonomous platform, we found significant marine snow accumulation from the surface to the mesopelagic zone in frontal regions between eddies. We suggest that the coupling of hydrodynamics at eddy edges and biological activity may enhance this process.
Naoya Kanna, Kazutaka Tateyama, Takuji Waseda, Anna Timofeeva, Maria Papadimitraki, Laura Whitmore, Hajime Obata, Daiki Nomura, Hiroshi Ogawa, Youhei Yamashita, and Igor Polyakov
Biogeosciences, 22, 1057–1076, https://doi.org/10.5194/bg-22-1057-2025, https://doi.org/10.5194/bg-22-1057-2025, 2025
Short summary
Short summary
This article presents data on iron and manganese, essential micronutrients for primary producers in the Arctic Laptev and East Siberian seas (LESS). There, observations were made through international cooperation with the Nansen and Amundsen Basin Observational System expedition during the late summer of 2021. The results from this study indicate that the major sources controlling the iron and manganese distributions on the LESS continental margins are river discharge and shelf sediment input.
Ben J. Fisher, Alex J. Poulton, Michael P. Meredith, Kimberlee Baldry, Oscar Schofield, and Sian F. Henley
Biogeosciences, 22, 975–994, https://doi.org/10.5194/bg-22-975-2025, https://doi.org/10.5194/bg-22-975-2025, 2025
Short summary
Short summary
The Southern Ocean is a rapidly warming environment, with subsequent impacts on ecosystems and biogeochemical cycling. This study examines changes in phytoplankton and biogeochemistry using a range of climate models. Under climate change, the Southern Ocean will be warmer, more acidic and more productive and will have reduced nutrient availability by 2100. However, there is substantial variability between models across key productivity parameters. We propose ways of reducing this uncertainty.
David Curbelo-Hernández, Fiz F. Pérez, Melchor González-Dávila, Sergey V. Gladyshev, Aridane G. González, David González-Santana, Antón Velo, Alexey Sokov, and J. Magdalena Santana-Casiano
Biogeosciences, 21, 5561–5589, https://doi.org/10.5194/bg-21-5561-2024, https://doi.org/10.5194/bg-21-5561-2024, 2024
Short summary
Short summary
The study evaluated CO2–carbonate system dynamics in the North Atlantic subpolar gyre during 2009–2019. Significant ocean acidification, largely due to rising anthropogenic CO2 levels, was found. Cooling, freshening, and enhanced convective processes intensified this trend, affecting calcite and aragonite saturation. The findings contribute to a deeper understanding of ocean acidification and improve our knowledge about its impact on marine ecosystems.
Yuye Han, Zvi Steiner, Zhimian Cao, Di Fan, Junhui Chen, Jimin Yu, and Minhan Dai
EGUsphere, https://doi.org/10.5194/egusphere-2024-3492, https://doi.org/10.5194/egusphere-2024-3492, 2024
Short summary
Short summary
Coccolithophore calcite accounts for a major fraction of particulate inorganic carbon (PIC) standing stocks in the western North Pacific, with a markedly higher contribution in the oligotrophic subtropical gyre than in the Kuroshio-Oyashio transition region, which highlights the importance of coccolithophores for PIC production in the pelagic ocean. We also found extensive dissolution of coccolithophore calcite in the oversaturated shallow waters primarily driven by microbial metabolic activity.
Yawouvi Dodji Soviadan, Miriam Beck, Joelle Habib, Alberto Baudena, Laetitia Drago, Alexandre Accardo, Remi Laxenaire, Sabrina Speich, Peter Brandt, Rainer Kiko, and Lars Stemmann
EGUsphere, https://doi.org/10.5194/egusphere-2024-3302, https://doi.org/10.5194/egusphere-2024-3302, 2024
Short summary
Short summary
Key parameters representing the gravity flux in global models are the sinking speed and the vertical attenuation of the exported material. We calculate for the first time, these parameters in situ for 6 intermittent blooms followed by export events using high-resolution (3 days) time series of 0–1000 m depth profiles from imaging sensor mounted on an Argo float. We show that sinking speed depends not only on size but also on the morphology of the particles, density being an important property.
Medhavi Pandey, Haimanti Biswas, Daniel Birgel, Nicole Burdanowitz, and Birgit Gaye
Biogeosciences, 21, 4681–4698, https://doi.org/10.5194/bg-21-4681-2024, https://doi.org/10.5194/bg-21-4681-2024, 2024
Short summary
Short summary
We analysed sea surface temperature (SST) proxy and plankton biomarkers in sediments that accumulate sinking material signatures from surface waters in the central Arabian Sea (21°–11° N, 64° E), a tropical basin impacted by monsoons. We saw a north–south SST gradient, and the biological proxies showed more organic matter from larger algae in the north. Smaller algae and zooplankton were more numerous in the south. These trends were related to ocean–atmospheric processes and oxygen availability.
Allison Hogikyan and Laure Resplandy
Biogeosciences, 21, 4621–4636, https://doi.org/10.5194/bg-21-4621-2024, https://doi.org/10.5194/bg-21-4621-2024, 2024
Short summary
Short summary
Rising atmospheric CO2 influences ocean carbon chemistry, leading to ocean acidification. Global warming introduces spatial patterns in the intensity of ocean acidification. We show that the most prominent spatial patterns are controlled by warming-driven changes in rainfall and evaporation, not by the direct effect of warming on carbon chemistry and pH. These evaporation and rainfall patterns oppose acidification in saltier parts of the ocean and enhance acidification in fresher regions.
Shunya Koseki, Lander R. Crespo, Jerry Tjiputra, Filippa Fransner, Noel S. Keenlyside, and David Rivas
Biogeosciences, 21, 4149–4168, https://doi.org/10.5194/bg-21-4149-2024, https://doi.org/10.5194/bg-21-4149-2024, 2024
Short summary
Short summary
We investigated how the physical biases of an Earth system model influence the marine biogeochemical processes in the tropical Atlantic. With four different configurations of the model, we have shown that the versions with better SST reproduction tend to better represent the primary production and air–sea CO2 flux in terms of climatology, seasonal cycle, and response to climate variability.
Lyuba Novi, Annalisa Bracco, Takamitsu Ito, and Yohei Takano
Biogeosciences, 21, 3985–4005, https://doi.org/10.5194/bg-21-3985-2024, https://doi.org/10.5194/bg-21-3985-2024, 2024
Short summary
Short summary
We explored the relationship between oxygen and stratification in the North Pacific Ocean using a combination of data mining and machine learning. We used isopycnic potential vorticity (IPV) as an indicator to quantify ocean ventilation and analyzed its predictability, a strong O2–IPV connection, and predictability for IPV in the tropical Pacific. This opens new routes for monitoring ocean O2 through few observational sites co-located with more abundant IPV measurements in the tropical Pacific.
Winfred Marshal, Jing Xiang Chung, Nur Hidayah Roseli, Roswati Md Amin, and Mohd Fadzil Bin Mohd Akhir
Biogeosciences, 21, 4007–4035, https://doi.org/10.5194/bg-21-4007-2024, https://doi.org/10.5194/bg-21-4007-2024, 2024
Short summary
Short summary
This study stands out for thoroughly examining CMIP6 ESMs' ability to simulate biogeochemical variables in the southern South China Sea, an economically important region. It assesses variables like chlorophyll, phytoplankton, nitrate, and oxygen on annual and seasonal scales. While global assessments exist, this study addresses a gap by objectively ranking 13 CMIP6 ocean biogeochemistry models' performance at a regional level, focusing on replicating specific observed biogeochemical variables.
Jens Terhaar
Biogeosciences, 21, 3903–3926, https://doi.org/10.5194/bg-21-3903-2024, https://doi.org/10.5194/bg-21-3903-2024, 2024
Short summary
Short summary
Despite the ocean’s importance in the carbon cycle and hence the climate, observing the ocean carbon sink remains challenging. Here, I use an ensemble of 12 models to understand drivers of decadal trends of the past, present, and future ocean carbon sink. I show that 80 % of the decadal trends in the multi-model mean ocean carbon sink can be explained by changes in decadal trends in atmospheric CO2. The remaining 20 % are due to internal climate variability and ocean heat uptake.
Reiner Steinfeldt, Monika Rhein, and Dagmar Kieke
Biogeosciences, 21, 3839–3867, https://doi.org/10.5194/bg-21-3839-2024, https://doi.org/10.5194/bg-21-3839-2024, 2024
Short summary
Short summary
We calculate the amount of anthropogenic carbon (Cant) in the Atlantic for the years 1990, 2000, 2010 and 2020. Cant is the carbon that is taken up by the ocean as a result of humanmade CO2 emissions. To determine the amount of Cant, we apply a technique that is based on the observations of other humanmade gases (e.g., chlorofluorocarbons). Regionally, changes in ocean ventilation have an impact on the storage of Cant. Overall, the increase in Cant is driven by the rising CO2 in the atmosphere.
Stephanie Delacroix, Tor Jensen Nystuen, August E. Dessen Tobiesen, Andrew L. King, and Erik Höglund
Biogeosciences, 21, 3677–3690, https://doi.org/10.5194/bg-21-3677-2024, https://doi.org/10.5194/bg-21-3677-2024, 2024
Short summary
Short summary
The addition of alkaline minerals into the ocean might reduce excessive anthropogenic CO2 emissions. Magnesium hydroxide can be added in large amounts because of its low seawater solubility without reaching harmful pH levels. The toxicity effect results of magnesium hydroxide, by simulating the expected concentrations from a ship's dispersion scenario, demonstrated low impacts on both sensitive and local assemblages of marine microalgae when compared to calcium hydroxide.
Brandon Stephens, Montserrat Roca-Martí, Amy Maas, Vinícius Amaral, Samantha Clevenger, Shawnee Traylor, Claudia Benitez-Nelson, Philip Boyd, Ken Buesseler, Craig Carlson, Nicolas Cassar, Margaret Estapa, Andrea Fassbender, Yibin Huang, Phoebe Lam, Olivier Marchal, Susanne Menden-Deuer, Nicola Paul, Alyson Santoro, David Siegel, and David Nicholson
EGUsphere, https://doi.org/10.5194/egusphere-2024-2251, https://doi.org/10.5194/egusphere-2024-2251, 2024
Short summary
Short summary
The ocean’s mesopelagic zone (MZ) plays a crucial role in the global carbon cycle. This study combines new and previously published measurements of organic carbon supply and demand collected in August 2018 for the MZ in the subarctic North Pacific Ocean. Supply was insufficient to meet demand in August, but supply entering into the MZ in the spring of 2018 could have met the August demand. Results suggest observations over seasonal time scales may help to close MZ carbon budgets.
Precious Mongwe, Matthew Long, Takamitsu Ito, Curtis Deutsch, and Yeray Santana-Falcón
Biogeosciences, 21, 3477–3490, https://doi.org/10.5194/bg-21-3477-2024, https://doi.org/10.5194/bg-21-3477-2024, 2024
Short summary
Short summary
We use a collection of measurements that capture the physiological sensitivity of organisms to temperature and oxygen and a CESM1 large ensemble to investigate how natural climate variations and climate warming will impact the ability of marine heterotrophic marine organisms to support habitats in the future. We find that warming and dissolved oxygen loss over the next several decades will reduce the volume of ocean habitats and will increase organisms' vulnerability to extremes.
Charly A. Moras, Tyler Cyronak, Lennart T. Bach, Renaud Joannes-Boyau, and Kai G. Schulz
Biogeosciences, 21, 3463–3475, https://doi.org/10.5194/bg-21-3463-2024, https://doi.org/10.5194/bg-21-3463-2024, 2024
Short summary
Short summary
We investigate the effects of mineral grain size and seawater salinity on magnesium hydroxide dissolution and calcium carbonate precipitation kinetics for ocean alkalinity enhancement. Salinity did not affect the dissolution, but calcium carbonate formed earlier at lower salinities due to the lower magnesium and dissolved organic carbon concentrations. Smaller grain sizes dissolved faster but calcium carbonate precipitated earlier, suggesting that medium grain sizes are optimal for kinetics.
Rosie M. Sheward, Christina Gebühr, Jörg Bollmann, and Jens O. Herrle
Biogeosciences, 21, 3121–3141, https://doi.org/10.5194/bg-21-3121-2024, https://doi.org/10.5194/bg-21-3121-2024, 2024
Short summary
Short summary
How quickly do marine microorganisms respond to salinity stress? Our experiments with the calcifying marine plankton Emiliania huxleyi show that growth and cell morphology responded to salinity stress within as little as 24–48 hours, demonstrating that morphology and calcification are sensitive to salinity over a range of timescales. Our results have implications for understanding the short-term role of E. huxleyi in biogeochemical cycles and in size-based paleoproxies for salinity.
Laura Marín-Samper, Javier Arístegui, Nauzet Hernández-Hernández, Joaquín Ortiz, Stephen D. Archer, Andrea Ludwig, and Ulf Riebesell
Biogeosciences, 21, 2859–2876, https://doi.org/10.5194/bg-21-2859-2024, https://doi.org/10.5194/bg-21-2859-2024, 2024
Short summary
Short summary
Our planet is facing a climate crisis. Scientists are working on innovative solutions that will aid in capturing the hard to abate emissions before it is too late. Exciting research reveals that ocean alkalinity enhancement, a key climate change mitigation strategy, does not harm phytoplankton, the cornerstone of marine ecosystems. Through meticulous study, we may have uncovered a positive relationship: up to a specific limit, enhancing ocean alkalinity boosts photosynthesis by certain species.
Kieran Curran, Tracy Villareal, and Robert T. Letscher
EGUsphere, https://doi.org/10.5194/egusphere-2024-1416, https://doi.org/10.5194/egusphere-2024-1416, 2024
Short summary
Short summary
This work provides a two year record of marine organic gel concentrations from an open ocean site in the subtropical North Pacific Ocean north of Hawaii. These microscopic gels are investigated to understand their importance as an understudied component of organic matter cycling by marine microbes. We find an important role for gel cycling during the summer months, helping explain previously contradictory estimates of nutrient supply and demand for the subtropical ocean.
France Van Wambeke, Pascal Conan, Mireille Pujo-Pay, Vincent Taillandier, Olivier Crispi, Alexandra Pavlidou, Sandra Nunige, Morgane Didry, Christophe Salmeron, and Elvira Pulido-Villena
Biogeosciences, 21, 2621–2640, https://doi.org/10.5194/bg-21-2621-2024, https://doi.org/10.5194/bg-21-2621-2024, 2024
Short summary
Short summary
Phosphomonoesterase (PME) and phosphodiesterase (PDE) activities over the epipelagic zone are described in the eastern Mediterranean Sea in winter and autumn. The types of concentration kinetics obtained for PDE (saturation at 50 µM, high Km, high turnover times) compared to those of PME (saturation at 1 µM, low Km, low turnover times) are discussed in regard to the possible inequal distribution of PDE and PME in the size continuum of organic material and accessibility to phosphodiesters.
Jenny Hieronymus, Magnus Hieronymus, Matthias Gröger, Jörg Schwinger, Raffaele Bernadello, Etienne Tourigny, Valentina Sicardi, Itzel Ruvalcaba Baroni, and Klaus Wyser
Biogeosciences, 21, 2189–2206, https://doi.org/10.5194/bg-21-2189-2024, https://doi.org/10.5194/bg-21-2189-2024, 2024
Short summary
Short summary
The timing of the net primary production annual maxima in the North Atlantic in the period 1750–2100 is investigated using two Earth system models and the high-emissions scenario SSP5-8.5. It is found that, for most of the region, the annual maxima occur progressively earlier, with the most change occurring after the year 2000. Shifts in the seasonality of the primary production may impact the entire ecosystem, which highlights the need for long-term monitoring campaigns in this area.
Nicole M. Travis, Colette L. Kelly, and Karen L. Casciotti
Biogeosciences, 21, 1985–2004, https://doi.org/10.5194/bg-21-1985-2024, https://doi.org/10.5194/bg-21-1985-2024, 2024
Short summary
Short summary
We conducted experimental manipulations of light level on microbial communities from the primary nitrite maximum. Overall, while individual microbial processes have different directions and magnitudes in their response to increasing light, the net community response is a decline in nitrite production with increasing light. We conclude that while increased light may decrease net nitrite production, high-light conditions alone do not exclude nitrification from occurring in the surface ocean.
Zoë Rebecca van Kemenade, Zeynep Erdem, Ellen Christine Hopmans, Jaap Smede Sinninghe Damsté, and Darci Rush
Biogeosciences, 21, 1517–1532, https://doi.org/10.5194/bg-21-1517-2024, https://doi.org/10.5194/bg-21-1517-2024, 2024
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Allanah Joy Paul, Mathias Haunost, Silvan Urs Goldenberg, Jens Hartmann, Nicolás Sánchez, Julieta Schneider, Niels Suitner, and Ulf Riebesell
EGUsphere, https://doi.org/10.5194/egusphere-2024-417, https://doi.org/10.5194/egusphere-2024-417, 2024
Short summary
Short summary
Ocean alkalinity enhancement (OAE) is being assessed for its potential to absorb atmospheric CO2 and store it for a long time. OAE still needs comprehensive assessment of its safety and effectiveness. We studied an idealised OAE application in a natural low nutrient ecosystem over one month. Our results showed that biogeochemical functioning remained mostly stable, but that the long-term capability for storing carbon may be limited at high alkalinity concentration.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
We present a new method for reconstructing ocean carbon using climate models and temperature and salinity observations. To test this method, we reconstruct modelled carbon using synthetic observations consistent with current sampling programmes. Sensitivity tests show skill in reconstructing carbon trends and variability within the upper 2000 m. Our results indicate that this method can be used for a new global estimate for ocean carbon content.
Alexandre Mignot, Hervé Claustre, Gianpiero Cossarini, Fabrizio D'Ortenzio, Elodie Gutknecht, Julien Lamouroux, Paolo Lazzari, Coralie Perruche, Stefano Salon, Raphaëlle Sauzède, Vincent Taillandier, and Anna Teruzzi
Biogeosciences, 20, 1405–1422, https://doi.org/10.5194/bg-20-1405-2023, https://doi.org/10.5194/bg-20-1405-2023, 2023
Short summary
Short summary
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
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.
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
Short summary
Short summary
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
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.
Cited articles
Anderson, S. P., Weller, R. A., and Lukas, R. B.: Surface buoyancy forcing
and the mixed layer of the Western Pacific warm pool: observations and 1d
model results, J. Climate, 9, 3056–3085, 1996.
Behrenfeld, M. J.: Abandoning sverdrup's critical depth hypothesis on
phytoplankton blooms, Ecology, 91, 977–989, https://doi.org/10.1890/09-1207.1, 2010.
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, https://doi.org/10.1029/2004GB002299, 2005.
Bessières, L., Rio, M. H., Dufau, C., Boone, C., and Pujol, M. I.: Ocean
state indicators from MyOcean altimeter products, Ocean Sci., 9, 545–560,
https://doi.org/10.5194/os-9-545-2013, 2013.
Borzelli, G. L. E., Gacic, M., Cardin, V., and Civitarese, G.: Eastern
Mediterranean transient and reversal of the Ionian sea circulation, Geophys.
Res. Lett., 36, L15108, https://doi.org/10.1029/2009GL039261, 2009.
Brainerd, K. E. and Gregg, M. C.: Surface mixed and mixing layer depths,
Deep-Sea Res. Pt. I, 42, 1521–1543, https://doi.org/10.1016/0967-0637(95)00068-H,
1995.
Bricaud, A., Bosc, E., and Antoine, D.: Algal biomass and sea surface
temperature in the Mediterranean Basin: Intercomparison of data from various
satellite sensors, and implications for primary production estimates, Remote
Sens. Environ., 81, 163–178, 2002.
Brody, S. R., Lozier, M. S., and Dunne, J. P.: A comparison of methods to
determine phytoplankton bloom initiation, J. Geophys. Res.-Oceans, 118, https://doi.org/10.1002/jgrc.20167, 2345–2357,
2013.
Buesseler, K. O.: The decoupling of production and particulate export in the
surface ocean, Global Biogeochem. Cy., 12, 297–310, 1998.
Civitarese, G., Gačić, M., Lipizer, M., and Eusebi Borzelli, G. L.:
On the impact of the Bimodal Oscillating System (BiOS) on the biogeochemistry
and biology of the Adriatic and Ionian Seas (Eastern Mediterranean),
Biogeosciences, 7, 3987–3997, https://doi.org/10.5194/bg-7-3987-2010, 2010.
Cermeño, P., Dutkiewicz, S., Harris, R. P., Follows, M., Schofield, O.,
and Falkowski, P. G.: The role of nutricline depth in regulating the ocean
carbon cycle, P. Natl. Acad. Sci. USA, 105, 20344–20349, 2008.
Cole, H., Henson, S., Martin, A., and Yool, A.: Mind the gap: The impact of
missing data on the calculation of phytoplankton phenology metrics, J.
Geophys. Res.-Oceans, 117, C08030, https://doi.org/10.1029/2012JC008249, 2012.
Cullen, J. J., Franks, P., Karl, D., and Longhurst, A.: Physical influences
on marine ecosystem dynamics, in: The sea, ideas and observations on progress
in the study of the seas, edited by: Robinson, A. R., McCarthy, J., and
Rothschild, B. J., Vol. 12, 297–336, John Wiley & Sons Inc, New York,
2002.
de Boyer Montegut, C., Madec, G., Fischer, A., Lazar, A., and Iudicone, D.:
Mixed layer depth over the global ocean: an examination of profile data and a
profile-based climatology, J. Geophys. Res.-Oceans, 109, C12003,
https://doi.org/10.1029/2004JC002378, 2004.
Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli, P., Kobayashi, S.,
Andrae, U., Balmaseda, M. A., Balsamo, G., Bauer, P., Bechtold, P., Beljaar, A. C. M.,
van de Berg, L., Bidlot, J., Bormann, N., Delsol, C., Dragani, R., Fuentes, M.,
Geer, A. J., Haimberger, L., Healy, S. B., Hersbach, H., Hólm, E. V., Isaksen, L.,
Kållberg, P., Köhler, M., Matricardi, M., McNally, A. P., Monge-Sanz, B. M., Morcrette, J.-J., Park, B.-K.,
Peubey, C., de Rosnay, P., Tavolato, C., Thépaut, J.-N., and Vitart, F.: The era-interim
reanalysis: configuration and performance of the data assimilation system, Q.
J. Roy. Meteor. Soc., 137, 553–597, 2011.
D'Ortenzio, F. and Ribera d'Alcalà, M.: On the trophic regimes of the
Mediterranean Sea: a satellite analysis, Biogeosciences, 6, 139–148,
https://doi.org/10.5194/bg-6-139-2009, 2009.
D'Ortenzio, F., Ragni, M., Marullo, S., and Ribera d'Alcala, M.: Did
biological activity in the Ionian sea change after the Eastern Mediterranean
Transient? Results from the analysis of remote sensing observations, J.
Geophys. Res.-Oceans, 108, 8113, https://doi.org/10.1029/2002JC001556, 2003.
D'Ortenzio, F., Iudicone, D., Montegut, C., Testor, P., Antoine, D., Marullo,
S., Santoleri, R., and Madec, G.: Seasonal variability of the mixed layer
depth in the Mediterranean sea as derived from in situ profiles, Geophys.
Res. Lett., 32, L12605, https://doi.org/10.1029/2005GL022463, 2005.
D'Ortenzio, F., Lavigne, H., Besson, F., Claustre, H., Coppola, L., Garcia, N., Laës-Huon, A., Le Reste, S., Malardé, D., Migon, C.,
Morin, P., Mortier, L., Poteau, A., Prieur, L., Raimbault, P., and Testor, P.: Observing
mixed layer depth, nitrate and chlorophyll concentrations in the Northwestern
Mediterranean: A combined satellite and NO3 profiling floats experiment, Geophys. Res.
Lett., 41, 6443–6451, https://doi.org/10.1002/2014GL061020,
2014.
Edwards, M. and Richardson A. J.: Impact of climate change on marine pelagic
phenology and trophic mismatch, Nature, 430, 881–884,
https://doi.org/10.1038/nature02808, 2004.
Falkowski, P. G., Ziemann, D., Kolber, Z., and Bienfang, P. K.: Role of eddy
pumping in enhancing primary production in the ocean, Nature, 352, 55–58,
1991.
Follows, M. and Dutkiewicz, S.: Meteorological modulation of the North
Atlantic spring bloom, Deep-Sea Res. Pt. II, 49, 321–344,
https://doi.org/10.1016/S0967-0645(01)00105-9, 2001.
Fratianni, C., Clementi, E., and Simoncelli, S.: Quality information document
for Mediterranean physics reanalysis product:
Medsea_reanalysis_phy_006_004, Tech. Rep.
CMEMS-Med-QUID-006-004-V2, MED-MFC, Ramonville Saint Agne, 2016.
Gačić, M., Civitarese, G., Miserocchi, S., Cardin, V., Crise, A., and Mauri,
E.: The open-ocean convection in the Southern Adriatic: a controlling
mechanism of the spring phytoplankton bloom, Cont. Shelf Res., 22,
1897–1908, https://doi.org/10.1016/S0278-4343(02)00050-X, 2002.
Gačić, M., Borzelli, G., Civitarese, G., Cardin, V., and Yari, S.: Can
internal processes sustain reversals of the ocean upper circulation? The
Ionian sea example, Geophys. Res. Lett., 37, L09608, https://doi.org/10.1029/2010GL043216, 2010.
Gačić, M., Civitarese, G., Kovacevic, V., Ursella, L., Bensi, M.,
Menna, M., Cardin, V., Poulain, P.-M., Cosoli, S., Notarstefano, G., and
Pizzi, C.: Extreme winter 2012 in the Adriatic: an example of climatic effect
on the BiOS rhythm, Ocean Sci., 10, 513–522,
https://doi.org/10.5194/os-10-513-2014, 2014.
Gill, A. E.: Atmosphere-ocean dynamics, Vol. 30, Academic press, San Diego,
1982.
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.
Hayward, T. L.: Primary production in the North Pacific central gyre: a
controversy with important implications, Trends Ecol. Evol., 6, 281–284,
https://doi.org/10.1016/0169-5347(91)90005-I, 1991.
Henson, S. A., Robinson, I., Allen, J. T., and Waniek, J. J.: Effect of
meteorological conditions on interannual variability in timing and magnitude
of the spring bloom in the Irminger basin, North Atlantic, Deep-Sea Res. Pt.
I, 53, 1601–1615, https://doi.org/10.1016/j.dsr.2006.07.009, 2006.
Henson, S. A., Dunne, J. P., and Sarmiento, J. L.: Decadal variability in
North Atlantic phytoplankton blooms, J. Geophys. Res., 114, C04013, https://doi.org/10.1029/2008JC005139,
2009.
Houpert, L., Testor, P., de Madron, X. D., Somot, S., D'Ortenzio, F.,
Estournel, C., and Lavigne, H.: Seasonal cycle of the mixed layer, the
seasonal thermocline and the upper-ocean heat storage rate in the
Mediterranean Sea derived from observations, Prog. Oceanogr., 132, 333–352,
2015.
Huisman, J., Oostveen, P. V., and Weissing, F. J.: Critical depth and
critical turbulence: two different mechanisms for the development of
phytoplankton blooms, Limnol. Oceanogr., 44, 1781–1787, 1999.
Ji, R., Davis, C. S., Chen, C., Townsend, D. W., Mountain, D. G., and
Beardsley, R. C.: Modeling the influence of low-salinity water inflow on
winter-spring phytoplankton dynamics in the Nova Scotian shelf–gulf of Maine
region, J. Plankton Res., 30, 1399–1416, 2008.
Ji, R., Edwards, M., Mackas, D. L., Runge, J. A., and Thomas, A. C: Marine
plankton phenology and life history in a changing climate: current research
and future directions, J. Plankton Res., 32, 1355–1368,
https://doi.org/10.1093/plankt/fbq062, 2010.
Kahru, M., Fiedler, P., Gille, S., Manzano, M., and Mitchell, B.: Sea level
anomalies control phytoplankton biomass in the Costa Rica dome area, Geophys.
Res. Lett., 34, L22601, https://doi.org/10.1029/2007GL031631, 2007.
Karl, D. M. and Lukas, R.: The Hawaii Ocean Time series (HOT) program:
background, rationale and field implementation, Deep-Sea Res. Pt. II, 43,
129–156, https://doi.org/10.1016/0967-0645(96)00005-7, 1996.
Karl, M. D.: A sea of change: biogeochemical variability in the North Pacific
subtropical gyre, Ecosystems, 2, 181–214, https://doi.org/10.1007/s100219900068, 1999.
Koeller, P., Fuentes-Yaco, C., Platt, T., Sathyendranath, S., Richards, A., Ouellet, P.,
Orr, D., Skúladóttir, U., Wieland, K., Savard, L., and Aschan, M.: Basin-scale
coherence in phenology of shrimps and phytoplankton in the North Atlantic
ocean, Science, 324, 791–793, https://doi.org/10.1126/science.1170987, 2009.
Lascaratos, A., Williams, R. G., and Tragou, E.: A mixed-layer study of the
formation of Levantine Intermediate Water, J. Geophys. Res., 98,
14739–14749, https://doi.org/10.1029/93JC00912, 1993.
Lavigne, H., D'Ortenzio, F., Migon, C., Claustre, H., Testor, P.,
d'Alcalà, M. R., Lavezza, R., Houpert, L., and Prieur, L.: Enhancing the
comprehension of mixed layer depth control on the Mediterranean phytoplankton
phenology, J. Geophys. Res.-Oceans, 118, 3416–3430, https://doi.org/10.1002/jgrc.20251,
2013.
Letelier, R. M., Karl, D. M., Abbott, M. R., and Bidigare, R. R.: Light
driven seasonal patterns of chlorophyll and nitrate in the lower euphotic
zone of the North Pacific subtropical gyre, Limnol. Oceanogr., 49, 508–519,
2004.
Lévy, M., Lehahn, Y., Andre, J.-M., Memery, L., Loisel, H., and Heifetz,
E.: Production regimes in the northeast atlantic: a study based on
Sea-viewing Wide Field-of-view Sensor (SeaWiFS) chlorophyll and ocean general
circulation model mixed layer depth, J. Geophys. Res.-Oceans, 110,
2156–2202, https://doi.org/10.1029/2004JC002771, 2005.
Longhurst, A. R.: Ecological Geography of the Sea, 2nd Edn., Academic Press,
London,
2006.
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.
Malanotte-Rizzol, P., Manca, B., Ribera D'Alcalà, M., Theocharis, A., Bergamasco, A.,
Bregant, D., Budillon, G., Civitarese, G., Georgopoulos, D., Michelato, A., Sansone, E.,
Scarazzato, P., and Souvermezoglou, E.: A
synthesis of the Ionian Sea hydrography, circulation and water mass pathways
during POEM-Phase-I, Prog. Oceanogr., 39, 153–204,
https://doi.org/10.1016/S0079-6611(97)00013-X, 1997.
Mann, K. and Lazier, J.: Dynamics of marine ecosystems: biological-physical
interactions in the oceans, Wiley-Blackwell, Oxford, 2006.
Marty, J.-C., Chiavérini, J., Pizay, M.-D., and Avril, B.: Seasonal and
interannual dynamics of nutrients and phytoplankton pigments in the Western
Mediterranean Sea at the DYFAMED time series station (1991–1999), Deep-Sea
Res. Pt. II, 49, 1965–1985, https://doi.org/10.1016/S0967-0645(02)00022-X, 2002.
Mayot, N., D'Ortenzio, F., Ribera d'Alcalà, M., Lavigne, H., and
Claustre, H.: Interannual variability of the Mediterranean trophic regimes
from ocean color satellites, Biogeosciences, 13, 1901–1917,
https://doi.org/10.5194/bg-13-1901-2016, 2016.
McGillicuddy, D., Robinson, A., Siegel, D., Jannasch, H., Johnson, R.,
Dickey, T., McNeil, J., Michaels, A., and Knap, A.: Influence of mesoscale
eddies on new production in the Sargasso Sea, Nature, 394, 263–266, 1998.
Omand, M. M. and Mahadevan,A.: Large-scale alignment of oceanic nitrate and
density, J. Geophys. Res.-Oceans, 118, 5322–5332, 2013.
O'Reilly, J. E., Maritorena, S., Siegel, D. A., O'Brien, M. C., Toole, D.,
Mitchell, B. G., Kahru, M., Chavez, F. P., Strutton, P., Cota, G. F., and
Hooker, S. B.: Ocean color chlorophyll a algorithms for SeaWiFS, OC2, and
OC4: Version 4. SeaWiFS postlaunch calibration and validation analyses, Part
3, 9–23, NASA Technical Memorandum 2000-206892, edited by: Hooker, S. B., Vol. 11, 2000.
Pasqueron de Fommervault, O., D'Ortenzio, F., Mangin, A., Serra, R., Migon,
C., Claustre, H., Lavigne, H., Ribera d'Alcalà, M., Prieur, L.,
Taillandier, V., Schmechtig, C., Poteau, A., Leymarie, E., Besson, F., and
Obolensky, G.: Seasonal variability of nutrient concentrations in the
Mediterranean Sea: contribution of Bio-Argo floats, J. Geophys. Res., 120,
8528–8550, https://doi.org/10.1002/2015JC011103, 2015.
Platt, T., Sathyendranath, S., White III, G. N., Fuentes-Yaco, C., Zhai, L.,
Devred, E., and Tang, C.: Diagnostic properties of phytoplankton time series
from remote sensing, Estuar. Coast., 33, 428–439, 2010.
Psarra, S., Zohary, T., Krom, M. D., Mantoura, R. F. C., Polychronaki, T.,
Stambler, N., Tanaka, T., Tselepides, A., and Thingstad, T. F.: Phytoplankton
response to a Lagrangian phosphate addition in the Levantine Sea (Eastern
Mediterranean), Deep-Sea Res. Pt. II, 52, 2944–2960, 2005.
Racault, M.-F., Le Quéré, C., Buitenhuis, E., Sathyendranath, S., and
Platt, T.: Phytoplankton phenology in the global ocean, Ecol. Indic., 14,
152–163, https://doi.org/10.1016/j.ecolind.2011.07.010, 2012.
Ribera d'Alcalà, M., Civitarese, G., Conversano, F., and Lavezza, R.:
Nutrient ratios and fluxes hint at overlooked processes in the Mediterranean
sea, J. Geophys. Res., 108, 8106, https://doi.org/10.1029/2002JC001650, 2003.
Rio, M.-H., Poulain, P.-M., Pascal, A., Mauri, E., Larnicol, G., and
Santoleri, R.: A Mean Dynamic Topography of the MediterraneanSea computed
from altimetric data, in-situ measurements and a general circulation model,
J. Marine Syst., 65, 484–508, 2007.
Salihoglu, I., Saydam, C., Basturk, Ö., Yilmaz, K., Gocmen, D.,
Hatipoglu, E., and Yilmaz, A.: Transport and distribution of nutrients and
chlorophyll-a by mesoscale eddies in the northeastern Mediterranean, Mar.
Chem., 29, 375–390, 1990.
Sasai, Y., Richards, K. J., Ishida, A., and Sasaki, H.: Effects of cyclonic
mesoscale eddies on the marine ecosystem in the Kuroshio extension region
using an eddy-resolving coupled physical-biological model, Ocean Dynam., 60,
693–704, 2010.
Steinberg, D., Carlson, C., Bates, N., Johnson, R., Michaels, A., and Knap,
A.: Overview of the US JGOFS Bermuda Atlantic Time-series Study (BATS): a
decade-scale look at ocean biology and biogeochemistry, Deep-Sea Res. Pt. II,
48, 1405–1447, 2001.
Storm, T., Boettcher, M., Grant, M., Zuhlke, M., Fomferra, N., Jackson, T.,
and Sathyendranath, S.: Ocean colour climate change initiative (oc_cci) –
phase one – product user guide, Tech. rep., Plymouth Marine Laboratory,
2013.
Sverdrup, H. U.: On conditions for the vernal blooming of phytoplankton, ICES
J. Mar. Sci., 18, 287–295, 1953.
Taylor, A., Geider, R. J., and Gilbert, F.: Seasonal and latitudinal
dependencies of phytoplankton carbon-to-chlorophyll a ratios: results of a
modelling study, Mar. Ecol.-Prog. Ser., 152, 51–66, 1997.
Taylor, J. and Ferrari, R.: Shutdown of turbulent convection as a new
criterion for the onset of spring phytoplankton blooms, Limnol. Oceanogr.,
56, 2293–2307, 2011.
Thingstad, T. F., Krom, M. D., Mantoura, R. F. C., Flaten, G. F., Groom, S.,
Herut, B., Kress, N., Law, C. S., Pasternak, A., Pitta, P., and Psarra, S.:
Nature of phosphorus limitation in the ultraoligotrophic eastern
Mediterranean, Science, 309, 1068–1071, 2005.
Volpe, G., Santoleri, R., Vellucci, V., d'Alcalà, M. R., Marullo, S., and
d'Ortenzio, F.: The colour of the Mediterranean Sea: Global versus regional
bio-optical algorithms evaluation and implication for satellite chlorophyll
estimates, Remote Sens. Environ., 107, 625–638, 2007.
While, J. and Haines, K.: A comparison of the variability of biological
nutrients against depth and potential density, Biogeosciences, 7, 1263–1269,
https://doi.org/10.5194/bg-7-1263-2010, 2010.
Williams, R. G. and Follows, M. J.: Physical transport of nutrients and the
maintenance of biological production, in: Ocean Biogeochemistry, 19–51,
Springer, New York, 2003.
Winn, C. D., Campbell, L., Christian, J. R., Letelier, R. M., Hebel, D. V.,
Dore, J. E., Fujieki, L., and Karl, D. M.: Seasonal variability in the
phytoplankton community of the north pacific subtropical gyre, Global
Biogeochem. Cy., 9, 605–620, https://doi.org/10.1029/95GB02149, 1995.
Winder, M. and Cloern, J. E.: The annual cycles of phytoplankton biomass,
Philos. T. R. Soc. B, 365, 3215–3226, https://doi.org/10.1098/rstb.2010.0125, 2010.
Yoder, J. A. and Kennelly, M. A.: Seasonal and ENSOvariability in global
ocean phytoplankton chlorophyll derived from 4 years of SeaWiFSmeasurements,
Global Biogeochem. Cy., 17, 1112, https://doi.org/10.1029/2002GB001942, 2003.
Yoder, J. A., McClain, C. R., Feldman, G. C., and Esaias, W. E.: Annual
cycles of phytoplankton chlorophyll concentrations in the global ocean:
asatellite view, Global Biogeochem. Cy., 7, 181–193,
https://doi.org/10.1029/93GB02358, 1993.
Zhai, L., Platt, T., Tang, C., Sathyendranath, S., and Walls, R. H.:
Phytoplankton phenology on the scotian shelf, ICES J. Mar. Sci., 68,
781–791, 2011.
Short summary
The north Ionian circulation, which is characterized by a decadal alternation of cyclonic and anticyclonic regime, affects phytoplankton dynamics and surface chlorophyll a. From satellite ocean color data, the cyclonic and anticyclonic regimes are compared and two chlorophyll a dynamics are observed: when circulation is anticyclonic, bloom initiation is in December and chlorophyll is low in March, whereas during the cyclonic regime, a late chlorophyll peak is commonly observed in March.
The north Ionian circulation, which is characterized by a decadal alternation of cyclonic and...
Altmetrics
Final-revised paper
Preprint