Articles | Volume 11, issue 19
https://doi.org/10.5194/bg-11-5581-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue:
https://doi.org/10.5194/bg-11-5581-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
13 Oct 2014
Research article |
| 13 Oct 2014
Chemical fate and settling of mineral dust in surface seawater after atmospheric deposition observed from dust seeding experiments in large mesocosms
K. Desboeufs
LISA, CNRS UMR7583, Université Paris-Diderot et Université Paris-Est Créteil, 61, av du Général de Gaulles, Créteil, France
N. Leblond
Sorbonne Universités, UPMC Univ Paris 06, UMS0829, Observatoire Océanologique, Villefranche-sur-Mer, France
T. Wagener
Université d'Aix-Marseille, CNRS/INSU, IRD, Institut Méditerranéen d'Océanologie (MIO), UM110, 13288 Marseille, France
E. Bon Nguyen
LISA, CNRS UMR7583, Université Paris-Diderot et Université Paris-Est Créteil, 61, av du Général de Gaulles, Créteil, France
Sorbonne Universités, UPMC Univ Paris 06, UMR7093, LOV, Observatoire océanologique, 06230, Villefranche/mer, France
CNRS, UMR7093, LOV, Observatoire océanologique, 06230, Villefranche/mer, France
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The elemental composition and solubility of several metals, including iron, at a coastal site in Namibia in August–September 2017, indicate that natural and anthropogenic dust had different solubility depending on mineralogy but mostly to the processing by fluoride ions from marine emissions, pointing out to the complexity of atmospheric/oceanic interactions in this region of the world influenced by the Benguela current and significant aerosol load.
Chiara Giorio, Anne Monod, Valerio Di Marco, Pierre Herckes, Denise Napolitano, Amy Sullivan, Gautier Landrot, Daniel Warnes, Marika Nasti, Sara D'Aronco, Agathe Gérardin, Nicolas Brun, Karine Desboeufs, Sylvain Triquet, Servanne Chevaillier, Claudia Di Biagio, Francesco Battaglia, Frédéric Burnet, Stuart J. Piketh, Andreas Namwoonde, Jean-François Doussin, and Paola Formenti
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A comparison between the solubility of trace metals in pairs of total suspended particulate (TSP) and fog water samples collected in Henties Bay, Namibia, during the AEROCLO-sA field campaign is presented. We found enhanced solubility of metals in fog samples which we attributed to metal-ligand complexes formation in the early stages of particle activation into droplets which can then remain in a kinetically stable form in fog or lead to the formation of colloidal nanoparticles.
Karine Desboeufs, Paola Formenti, Raquel Torres-Sánchez, Kerstin Schepanski, Jean-Pierre Chaboureau, Hendrik Andersen, Jan Cermak, Stefanie Feuerstein, Benoit Laurent, Danitza Klopper, Andreas Namwoonde, Mathieu Cazaunau, Servanne Chevaillier, Anaïs Feron, Cécile Mirande-Bret, Sylvain Triquet, and Stuart J. Piketh
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This study investigates the fractional solubility of iron (Fe) in dust particles along the coast of Namibia, a critical region for the atmospheric Fe supply of the South Atlantic Ocean. Our results suggest a possible two-way interplay whereby marine biogenic emissions from the coastal marine ecosystems into the atmosphere would increase the solubility of Fe-bearing dust by photo-reduction processes. The subsequent deposition of soluble Fe could act to further enhance marine biogenic emissions.
Thomas Audoux, Benoit Laurent, Karine Desboeufs, Gael Noyalet, Franck Maisonneuve, Olivier Lauret, and Servanne Chevaillier
Atmos. Chem. Phys., 23, 13485–13503, https://doi.org/10.5194/acp-23-13485-2023, https://doi.org/10.5194/acp-23-13485-2023, 2023
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In the Paris region, a campaign was conducted to study wet deposition of aerosol particles during rainfall events. Simultaneous measurements of aerosol and wet deposition allowed us to discuss their transfer from the atmosphere to rain. Chemical evolution within events revealed meteorology, atmospheric conditions and local vs. long range sources as key factors. This study highlights the variability of wet deposition and the need to consider event-specific factors to understand its mechanisms.
Karine Desboeufs, Franck Fu, Matthieu Bressac, Antonio Tovar-Sánchez, Sylvain Triquet, Jean-François Doussin, Chiara Giorio, Patrick Chazette, Julie Disnaquet, Anaïs Feron, Paola Formenti, Franck Maisonneuve, Araceli Rodríguez-Romero, Pascal Zapf, François Dulac, and Cécile Guieu
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Matthieu Bressac, Thibaut Wagener, Nathalie Leblond, Antonio Tovar-Sánchez, Céline Ridame, Vincent Taillandier, Samuel Albani, Sophie Guasco, Aurélie Dufour, Stéphanie H. M. Jacquet, François Dulac, Karine Desboeufs, and Cécile Guieu
Biogeosciences, 18, 6435–6453, https://doi.org/10.5194/bg-18-6435-2021, https://doi.org/10.5194/bg-18-6435-2021, 2021
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Phytoplankton growth is limited by the availability of iron in about 50 % of the ocean. Atmospheric deposition of desert dust represents a key source of iron. Here, we present direct observations of dust deposition in the Mediterranean Sea. A key finding is that the input of iron from dust primarily occurred in the deep ocean, while previous studies mainly focused on the ocean surface. This new insight will enable us to better represent controls on global marine productivity in models.
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
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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.
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
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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.
Evelyn Freney, Karine Sellegri, Alessia Nicosia, Leah R. Williams, Matteo Rinaldi, Jonathan T. Trueblood, André S. H. Prévôt, Melilotus Thyssen, Gérald Grégori, Nils Haëntjens, Julie Dinasquet, Ingrid Obernosterer, France Van Wambeke, Anja Engel, Birthe Zäncker, Karine Desboeufs, Eija Asmi, Hilkka Timonen, and Cécile Guieu
Atmos. Chem. Phys., 21, 10625–10641, https://doi.org/10.5194/acp-21-10625-2021, https://doi.org/10.5194/acp-21-10625-2021, 2021
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In this work, we present observations of the organic aerosol content in primary sea spray aerosols (SSAs) continuously generated along a 5-week cruise in the Mediterranean. This information is combined with seawater biogeochemical properties also measured continuously along the ship track to develop a number of parametrizations that can be used in models to determine SSA organic content in oligotrophic waters that represent 60 % of the oceans from commonly measured seawater variables.
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
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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.
Kahina Djaoudi, France Van Wambeke, Aude Barani, Nagib Bhairy, Servanne Chevaillier, Karine Desboeufs, Sandra Nunige, Mohamed Labiadh, Thierry Henry des Tureaux, Dominique Lefèvre, Amel Nouara, Christos Panagiotopoulos, Marc Tedetti, and Elvira Pulido-Villena
Biogeosciences, 17, 6271–6285, https://doi.org/10.5194/bg-17-6271-2020, https://doi.org/10.5194/bg-17-6271-2020, 2020
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
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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.
Antonio Tovar-Sánchez, Araceli Rodríguez-Romero, Anja Engel, Birthe Zäncker, Franck Fu, Emilio Marañón, María Pérez-Lorenzo, Matthieu Bressac, Thibaut Wagener, Sylvain Triquet, Guillaume Siour, Karine Desboeufs, and Cécile Guieu
Biogeosciences, 17, 2349–2364, https://doi.org/10.5194/bg-17-2349-2020, https://doi.org/10.5194/bg-17-2349-2020, 2020
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Residence times of particulate metals derived from aerosol deposition in the Sea Surface Microlayer of the Mediterranean Sea ranged from a couple of minutes (e.g., for Fe) to a few hours (e.g., for Cu). Microbial activity seems to play an important role in in this process and in the concentration and distribution of metals between diferent water layers.
Laurent Menut, Guillaume Siour, Bertrand Bessagnet, Florian Couvidat, Emilie Journet, Yves Balkanski, and Karine Desboeufs
Geosci. Model Dev., 13, 2051–2071, https://doi.org/10.5194/gmd-13-2051-2020, https://doi.org/10.5194/gmd-13-2051-2020, 2020
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Modelling of mineral dust is often done using one single mean species. In this study, differentiated mineral species with their chemical composition are implemented in the CHIMERE regional chemistry-transport model by using global databases. Simulations are carried out to quantify the realism and gain of such mineralogy.
Patrick Chazette, Cyrille Flamant, Julien Totems, Marco Gaetani, Gwendoline Smith, Alexandre Baron, Xavier Landsheere, Karine Desboeufs, Jean-François Doussin, and Paola Formenti
Atmos. Chem. Phys., 19, 14979–15005, https://doi.org/10.5194/acp-19-14979-2019, https://doi.org/10.5194/acp-19-14979-2019, 2019
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Evolution of the vertical distribution and optical properties of aerosols in the free troposphere is analysed for the first time over the Namibian coast, a region where uncertainties on aerosol–cloud coupling in climate simulations are significant. The high variability of atmospheric aerosol composition is highlighted using a combination of ground-based, airborne and space-borne lidar. Aerosols are mainly transported from Angola, but part of the highest aerosol layer may come from South America.
Marc D. Mallet, Barbara D'Anna, Aurélie Même, Maria Chiara Bove, Federico Cassola, Giandomenico Pace, Karine Desboeufs, Claudia Di Biagio, Jean-Francois Doussin, Michel Maille, Dario Massabò, Jean Sciare, Pascal Zapf, Alcide Giorgio di Sarra, and Paola Formenti
Atmos. Chem. Phys., 19, 11123–11142, https://doi.org/10.5194/acp-19-11123-2019, https://doi.org/10.5194/acp-19-11123-2019, 2019
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We present findings from a summertime field campaign at the remote island of Lampedusa in the central Mediterranean Sea. We show that the aerosol loading is similar to coastal sites around the Mediterranean. We observe higher loadings of sulfate and aged organic aerosol from air masses transported over the central and eastern Mediterranean in comparison to those from the western Mediterranean. These results highlight the rarity of pristine air masses, even in remote marine environments.
David Au Yang, Pierre Cartigny, Karine Desboeufs, and David Widory
Atmos. Chem. Phys., 19, 3779–3796, https://doi.org/10.5194/acp-19-3779-2019, https://doi.org/10.5194/acp-19-3779-2019, 2019
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Sulfates present in urban aerosols collected worldwide usually exhibit 33S-anomalies whose origin remains unclear. Besides, the sulfate concentration is not very well modelled nowadays, which, coupled with the isotopic composition anomaly on the 33S, would highlight the presence of at least an additional oxidation pathway, different from O2+TMI, O3, OH, H2O2 and NO2. We suggest here the implication of two other possible oxidation pathways.
Paola Formenti, Stuart John Piketh, Andreas Namwoonde, Danitza Klopper, Roelof Burger, Mathieu Cazaunau, Anaïs Feron, Cécile Gaimoz, Stephen Broccardo, Nicola Walton, Karine Desboeufs, Guillaume Siour, Mattheus Hanghome, Samuel Mafwila, Edosa Omoregie, Wolfgang Junkermann, and Willy Maenhaut
Atmos. Chem. Phys., 18, 17003–17016, https://doi.org/10.5194/acp-18-17003-2018, https://doi.org/10.5194/acp-18-17003-2018, 2018
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Three-years of continuous measurements at the Henties Bay Aerosol Observatory (HBAO; 22°S, 14°05’E), Namibia, show that during the austral wintertime, long- and medium-range transport of pollution from biomass and fossil fuel burning give rise to peaks of light-absorbing black carbon aerosols into the marine boundary layer ahead of the main biomass burning season. This could affect the cloud properties.
Karine Desboeufs, Elisabeth Bon Nguyen, Servanne Chevaillier, Sylvain Triquet, and François Dulac
Atmos. Chem. Phys., 18, 14477–14492, https://doi.org/10.5194/acp-18-14477-2018, https://doi.org/10.5194/acp-18-14477-2018, 2018
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Atmospheric deposition is known to be a major source of nutrients for the marine biosphere in the Mediterranean Sea. The study of the origin of nutrients and trace metals in Corsica presented here shows that the dust events were the major sources of Si and Fe. Conversely, combustion sources predominated the inputs of N, P, and trace metals. This work showed the importance of considering background anthropogenic deposition for estimating the impact of atmospheric forcing on marine biota.
Yinghe Fu, Karine Desboeufs, Julie Vincent, Elisabeth Bon Nguyen, Benoit Laurent, Remi Losno, and François Dulac
Atmos. Meas. Tech., 10, 4389–4401, https://doi.org/10.5194/amt-10-4389-2017, https://doi.org/10.5194/amt-10-4389-2017, 2017
Julie Vincent, Benoit Laurent, Rémi Losno, Elisabeth Bon Nguyen, Pierre Roullet, Stéphane Sauvage, Servanne Chevaillier, Patrice Coddeville, Noura Ouboulmane, Alcide Giorgio di Sarra, Antonio Tovar-Sánchez, Damiano Sferlazzo, Ana Massanet, Sylvain Triquet, Rafael Morales Baquero, Michel Fornier, Cyril Coursier, Karine Desboeufs, François Dulac, and Gilles Bergametti
Atmos. Chem. Phys., 16, 8749–8766, https://doi.org/10.5194/acp-16-8749-2016, https://doi.org/10.5194/acp-16-8749-2016, 2016
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To investigate dust deposition dynamics at the regional scale, five automatic deposition collectors named CARAGA have been deployed in the western Mediterranean basin (Lampedusa, Majorca, Corsica, Frioul and Le Casset) during 1 to 3 years depending on the station. Complementary observations provided by both satellite and air mass trajectories are used to identify the dust provenance areas and the transport pathways from the Sahara to the stations for the studied period.
M. Mallet, F. Dulac, P. Formenti, P. Nabat, J. Sciare, G. Roberts, J. Pelon, G. Ancellet, D. Tanré, F. Parol, C. Denjean, G. Brogniez, A. di Sarra, L. Alados-Arboledas, J. Arndt, F. Auriol, L. Blarel, T. Bourrianne, P. Chazette, S. Chevaillier, M. Claeys, B. D'Anna, Y. Derimian, K. Desboeufs, T. Di Iorio, J.-F. Doussin, P. Durand, A. Féron, E. Freney, C. Gaimoz, P. Goloub, J. L. Gómez-Amo, M. J. Granados-Muñoz, N. Grand, E. Hamonou, I. Jankowiak, M. Jeannot, J.-F. Léon, M. Maillé, S. Mailler, D. Meloni, L. Menut, G. Momboisse, J. Nicolas, T. Podvin, V. Pont, G. Rea, J.-B. Renard, L. Roblou, K. Schepanski, A. Schwarzenboeck, K. Sellegri, M. Sicard, F. Solmon, S. Somot, B Torres, J. Totems, S. Triquet, N. Verdier, C. Verwaerde, F. Waquet, J. Wenger, and P. Zapf
Atmos. Chem. Phys., 16, 455–504, https://doi.org/10.5194/acp-16-455-2016, https://doi.org/10.5194/acp-16-455-2016, 2016
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The aim of this article is to present an experimental campaign over the Mediterranean focused on aerosol-radiation measurements and modeling. Results indicate an important atmospheric loading associated with a moderate absorbing ability of mineral dust. Observations suggest a complex vertical structure and size distributions characterized by large aerosols within dust plumes. The radiative effect is highly variable, with negative forcing over the Mediterranean and positive over northern Africa.
Y. Zhang, N. Mahowald, R. A. Scanza, E. Journet, K. Desboeufs, S. Albani, J. F. Kok, G. Zhuang, Y. Chen, D. D. Cohen, A. Paytan, M. D. Patey, E. P. Achterberg, J. P. Engelbrecht, and K. W. Fomba
Biogeosciences, 12, 5771–5792, https://doi.org/10.5194/bg-12-5771-2015, https://doi.org/10.5194/bg-12-5771-2015, 2015
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A new technique to determine a size-fractionated global soil elemental emission inventory based on a global soil and mineralogical data set is introduced. Spatial variability of mineral dust elemental fractions (8 elements, e.g., Ca, Fe, Al) is identified on a global scale, particularly for Ca. The Ca/Al ratio ranged between 0.1 and 5.0 and is confirmed as an indicator of dust source regions by a global dust model. Total and soluble dust element fluxes into different ocean basins are estimated.
C. Guieu, C. Ridame, E. Pulido-Villena, M. Bressac, K. Desboeufs, and F. Dulac
Biogeosciences, 11, 5621–5635, https://doi.org/10.5194/bg-11-5621-2014, https://doi.org/10.5194/bg-11-5621-2014, 2014
P. Formenti, S. Caquineau, K. Desboeufs, A. Klaver, S. Chevaillier, E. Journet, and J. L. Rajot
Atmos. Chem. Phys., 14, 10663–10686, https://doi.org/10.5194/acp-14-10663-2014, https://doi.org/10.5194/acp-14-10663-2014, 2014
M. Bressac, C. Guieu, D. Doxaran, F. Bourrin, K. Desboeufs, N. Leblond, and C. Ridame
Biogeosciences, 11, 1007–1020, https://doi.org/10.5194/bg-11-1007-2014, https://doi.org/10.5194/bg-11-1007-2014, 2014
R. Paris and K. V. Desboeufs
Atmos. Chem. Phys., 13, 4895–4905, https://doi.org/10.5194/acp-13-4895-2013, https://doi.org/10.5194/acp-13-4895-2013, 2013
Paola Formenti, Chiara Giorio, Karine Desboeufs, Alexander Zherebker, Marco Gaetani, Clarissa Baldo, Gautier Landrot, Simona Montebello, Servanne Chevaillier, Sylvain Triquet, Guillaume Siour, Claudia Di Biagio, Francesco Battaglia, Jean-François Doussin, Anais Feron, Andreas Namwoonde, and Stuart John Piketh
EGUsphere, https://doi.org/10.5194/egusphere-2025-446, https://doi.org/10.5194/egusphere-2025-446, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
The elemental composition and solubility of several metals, including iron, at a coastal site in Namibia in August–September 2017, indicate that natural and anthropogenic dust had different solubility depending on mineralogy but mostly to the processing by fluoride ions from marine emissions, pointing out to the complexity of atmospheric/oceanic interactions in this region of the world influenced by the Benguela current and significant aerosol load.
Nicolas Metzl, Jonathan Fin, Claire Lo Monaco, Claude Mignon, Samir Alliouane, Bruno Bombled, Jacqueline Boutin, Yann Bozec, Steeve Comeau, Pascal Conan, Laurent Coppola, Pascale Cuet, Eva Ferreira, Jean-Pierre Gattuso, Frédéric Gazeau, Catherine Goyet, Emilie Grossteffan, Bruno Lansard, Dominique Lefèvre, Nathalie Lefèvre, Coraline Leseurre, Sébastien Petton, Mireille Pujo-Pay, Christophe Rabouille, Gilles Reverdin, Céline Ridame, Peggy Rimmelin-Maury, Jean-François Ternon, Franck Touratier, Aline Tribollet, Thibaut Wagener, and Cathy Wimart-Rousseau
Earth Syst. Sci. Data, 17, 1075–1100, https://doi.org/10.5194/essd-17-1075-2025, https://doi.org/10.5194/essd-17-1075-2025, 2025
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This work presents a new synthesis of 67 000 total alkalinity and total dissolved inorganic carbon observations obtained between 1993 and 2023 in the global ocean, coastal zones, and the Mediterranean Sea. We describe the data assemblage and associated quality control and discuss some potential uses of this dataset. The dataset is provided in a single format and includes the quality flag for each sample.
Chiara Giorio, Anne Monod, Valerio Di Marco, Pierre Herckes, Denise Napolitano, Amy Sullivan, Gautier Landrot, Daniel Warnes, Marika Nasti, Sara D'Aronco, Agathe Gérardin, Nicolas Brun, Karine Desboeufs, Sylvain Triquet, Servanne Chevaillier, Claudia Di Biagio, Francesco Battaglia, Frédéric Burnet, Stuart J. Piketh, Andreas Namwoonde, Jean-François Doussin, and Paola Formenti
EGUsphere, https://doi.org/10.5194/egusphere-2024-4140, https://doi.org/10.5194/egusphere-2024-4140, 2025
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A comparison between the solubility of trace metals in pairs of total suspended particulate (TSP) and fog water samples collected in Henties Bay, Namibia, during the AEROCLO-sA field campaign is presented. We found enhanced solubility of metals in fog samples which we attributed to metal-ligand complexes formation in the early stages of particle activation into droplets which can then remain in a kinetically stable form in fog or lead to the formation of colloidal nanoparticles.
Lucille Barré, Frédéric Diaz, Thibaut Wagener, Camille Mazoyer, Christophe Yohia, and Christel Pinazo
Geosci. Model Dev., 17, 5851–5882, https://doi.org/10.5194/gmd-17-5851-2024, https://doi.org/10.5194/gmd-17-5851-2024, 2024
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The carbonate system is typically studied using measurements, but modeling can contribute valuable insights. Using a biogeochemical model, we propose a new representation of total alkalinity, dissolved inorganic carbon, pCO2, and pH in a highly dynamic Mediterranean coastal area, the Bay of Marseille, a useful addition to measurements. Through a detailed analysis of pCO2 and air–sea CO2 fluxes, we show that variations are strongly impacted by the hydrodynamic processes that affect the bay.
Karine Desboeufs, Paola Formenti, Raquel Torres-Sánchez, Kerstin Schepanski, Jean-Pierre Chaboureau, Hendrik Andersen, Jan Cermak, Stefanie Feuerstein, Benoit Laurent, Danitza Klopper, Andreas Namwoonde, Mathieu Cazaunau, Servanne Chevaillier, Anaïs Feron, Cécile Mirande-Bret, Sylvain Triquet, and Stuart J. Piketh
Atmos. Chem. Phys., 24, 1525–1541, https://doi.org/10.5194/acp-24-1525-2024, https://doi.org/10.5194/acp-24-1525-2024, 2024
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This study investigates the fractional solubility of iron (Fe) in dust particles along the coast of Namibia, a critical region for the atmospheric Fe supply of the South Atlantic Ocean. Our results suggest a possible two-way interplay whereby marine biogenic emissions from the coastal marine ecosystems into the atmosphere would increase the solubility of Fe-bearing dust by photo-reduction processes. The subsequent deposition of soluble Fe could act to further enhance marine biogenic emissions.
Nicolas Metzl, Jonathan Fin, Claire Lo Monaco, Claude Mignon, Samir Alliouane, David Antoine, Guillaume Bourdin, Jacqueline Boutin, Yann Bozec, Pascal Conan, Laurent Coppola, Frédéric Diaz, Eric Douville, Xavier Durrieu de Madron, Jean-Pierre Gattuso, Frédéric Gazeau, Melek Golbol, Bruno Lansard, Dominique Lefèvre, Nathalie Lefèvre, Fabien Lombard, Férial Louanchi, Liliane Merlivat, Léa Olivier, Anne Petrenko, Sébastien Petton, Mireille Pujo-Pay, Christophe Rabouille, Gilles Reverdin, Céline Ridame, Aline Tribollet, Vincenzo Vellucci, Thibaut Wagener, and Cathy Wimart-Rousseau
Earth Syst. Sci. Data, 16, 89–120, https://doi.org/10.5194/essd-16-89-2024, https://doi.org/10.5194/essd-16-89-2024, 2024
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This work presents a synthesis of 44 000 total alkalinity and dissolved inorganic carbon observations obtained between 1993 and 2022 in the Global Ocean and the Mediterranean Sea at the surface and in the water column. Seawater samples were measured using the same method and calibrated with international Certified Reference Material. We describe the data assemblage, quality control and some potential uses of this dataset.
Lucille Barré, Frédéric Diaz, Thibaut Wagener, France Van Wambeke, Camille Mazoyer, Christophe Yohia, and Christel Pinazo
Geosci. Model Dev., 16, 6701–6739, https://doi.org/10.5194/gmd-16-6701-2023, https://doi.org/10.5194/gmd-16-6701-2023, 2023
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While several studies have shown that mixotrophs play a crucial role in the carbon cycle, the impact of environmental forcings on their dynamics remains poorly investigated. Using a biogeochemical model that considers mixotrophs, we study the impact of light and nutrient concentration on the ecosystem composition in a highly dynamic Mediterranean coastal area: the Bay of Marseille. We show that mixotrophs cope better with oligotrophic conditions compared to strict auto- and heterotrophs.
Thomas Audoux, Benoit Laurent, Karine Desboeufs, Gael Noyalet, Franck Maisonneuve, Olivier Lauret, and Servanne Chevaillier
Atmos. Chem. Phys., 23, 13485–13503, https://doi.org/10.5194/acp-23-13485-2023, https://doi.org/10.5194/acp-23-13485-2023, 2023
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In the Paris region, a campaign was conducted to study wet deposition of aerosol particles during rainfall events. Simultaneous measurements of aerosol and wet deposition allowed us to discuss their transfer from the atmosphere to rain. Chemical evolution within events revealed meteorology, atmospheric conditions and local vs. long range sources as key factors. This study highlights the variability of wet deposition and the need to consider event-specific factors to understand its mechanisms.
Julie Dinasquet, Estelle Bigeard, Frédéric Gazeau, Farooq Azam, Cécile Guieu, Emilio Marañón, Céline Ridame, France Van Wambeke, Ingrid Obernosterer, and Anne-Claire Baudoux
Biogeosciences, 19, 1303–1319, https://doi.org/10.5194/bg-19-1303-2022, https://doi.org/10.5194/bg-19-1303-2022, 2022
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Saharan dust deposition of nutrients and trace metals is crucial to microbes in the Mediterranean Sea. Here, we tested the response of microbial and viral communities to simulated dust deposition under present and future conditions of temperature and pH. Overall, the effect of the deposition was dependent on the initial microbial assemblage, and future conditions will intensify microbial responses. We observed effects on trophic interactions, cascading all the way down to viral processes.
Karine Desboeufs, Franck Fu, Matthieu Bressac, Antonio Tovar-Sánchez, Sylvain Triquet, Jean-François Doussin, Chiara Giorio, Patrick Chazette, Julie Disnaquet, Anaïs Feron, Paola Formenti, Franck Maisonneuve, Araceli Rodríguez-Romero, Pascal Zapf, François Dulac, and Cécile Guieu
Atmos. Chem. Phys., 22, 2309–2332, https://doi.org/10.5194/acp-22-2309-2022, https://doi.org/10.5194/acp-22-2309-2022, 2022
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This article reports the first concurrent sampling of wet deposition samples and surface seawater and was performed during the PEACETIME cruise in the remote Mediterranean (May–June 2017). Through the chemical composition of trace metals (TMs) in these samples, it emphasizes the decrease of atmospheric metal pollution in this area during the last few decades and the critical role of wet deposition as source of TMs for Mediterranean surface seawater, especially for intense dust deposition events.
Céline Ridame, Julie Dinasquet, Søren Hallstrøm, Estelle Bigeard, Lasse Riemann, France Van Wambeke, Matthieu Bressac, Elvira Pulido-Villena, Vincent Taillandier, Fréderic Gazeau, Antonio Tovar-Sanchez, Anne-Claire Baudoux, and Cécile Guieu
Biogeosciences, 19, 415–435, https://doi.org/10.5194/bg-19-415-2022, https://doi.org/10.5194/bg-19-415-2022, 2022
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We show that in the Mediterranean Sea spatial variability in N2 fixation is related to the diazotrophic community composition reflecting different nutrient requirements among species. Nutrient supply by Saharan dust is of great importance to diazotrophs, as shown by the strong stimulation of N2 fixation after a simulated dust event under present and future climate conditions; the magnitude of stimulation depends on the degree of limitation related to the diazotrophic community composition.
Matthieu Bressac, Thibaut Wagener, Nathalie Leblond, Antonio Tovar-Sánchez, Céline Ridame, Vincent Taillandier, Samuel Albani, Sophie Guasco, Aurélie Dufour, Stéphanie H. M. Jacquet, François Dulac, Karine Desboeufs, and Cécile Guieu
Biogeosciences, 18, 6435–6453, https://doi.org/10.5194/bg-18-6435-2021, https://doi.org/10.5194/bg-18-6435-2021, 2021
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Phytoplankton growth is limited by the availability of iron in about 50 % of the ocean. Atmospheric deposition of desert dust represents a key source of iron. Here, we present direct observations of dust deposition in the Mediterranean Sea. A key finding is that the input of iron from dust primarily occurred in the deep ocean, while previous studies mainly focused on the ocean surface. This new insight will enable us to better represent controls on global marine productivity in models.
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
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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.
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
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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
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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.
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
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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.
Evelyn Freney, Karine Sellegri, Alessia Nicosia, Leah R. Williams, Matteo Rinaldi, Jonathan T. Trueblood, André S. H. Prévôt, Melilotus Thyssen, Gérald Grégori, Nils Haëntjens, Julie Dinasquet, Ingrid Obernosterer, France Van Wambeke, Anja Engel, Birthe Zäncker, Karine Desboeufs, Eija Asmi, Hilkka Timonen, and Cécile Guieu
Atmos. Chem. Phys., 21, 10625–10641, https://doi.org/10.5194/acp-21-10625-2021, https://doi.org/10.5194/acp-21-10625-2021, 2021
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In this work, we present observations of the organic aerosol content in primary sea spray aerosols (SSAs) continuously generated along a 5-week cruise in the Mediterranean. This information is combined with seawater biogeochemical properties also measured continuously along the ship track to develop a number of parametrizations that can be used in models to determine SSA organic content in oligotrophic waters that represent 60 % of the oceans from commonly measured seawater variables.
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
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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.
Jonathan V. Trueblood, Alessia Nicosia, Anja Engel, Birthe Zäncker, Matteo Rinaldi, Evelyn Freney, Melilotus Thyssen, Ingrid Obernosterer, Julie Dinasquet, Franco Belosi, Antonio Tovar-Sánchez, Araceli Rodriguez-Romero, Gianni Santachiara, Cécile Guieu, and Karine Sellegri
Atmos. Chem. Phys., 21, 4659–4676, https://doi.org/10.5194/acp-21-4659-2021, https://doi.org/10.5194/acp-21-4659-2021, 2021
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Sea spray aerosols (SSAs) can be an important source of ice-nucleating particles (INPs) that impact cloud properties over the oceans. In the Mediterranean Sea, we found that the INPs in the seawater surface microlayer increased by an order of magnitude after a rain dust event that impacted iron and bacterial abundances. The INP properties of SSA (INPSSA) increased after a 3 d delay. Outside this event, INPSSA could be parameterized as a function of the seawater biogeochemistry.
Katixa Lajaunie-Salla, Frédéric Diaz, Cathy Wimart-Rousseau, Thibaut Wagener, Dominique Lefèvre, Christophe Yohia, Irène Xueref-Remy, Brian Nathan, Alexandre Armengaud, and Christel Pinazo
Geosci. Model Dev., 14, 295–321, https://doi.org/10.5194/gmd-14-295-2021, https://doi.org/10.5194/gmd-14-295-2021, 2021
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A biogeochemical model of planktonic food webs including a carbonate balance module is applied in the Bay of Marseille (France) to represent the carbon marine cycle expected to change in the future owing to significant increases in anthropogenic emissions of CO2. The model correctly simulates the ranges and seasonal dynamics of most variables of the carbonate system (pH). This study shows that external physical forcings have an important impact on the carbonate equilibrium in this coastal area.
Kahina Djaoudi, France Van Wambeke, Aude Barani, Nagib Bhairy, Servanne Chevaillier, Karine Desboeufs, Sandra Nunige, Mohamed Labiadh, Thierry Henry des Tureaux, Dominique Lefèvre, Amel Nouara, Christos Panagiotopoulos, Marc Tedetti, and Elvira Pulido-Villena
Biogeosciences, 17, 6271–6285, https://doi.org/10.5194/bg-17-6271-2020, https://doi.org/10.5194/bg-17-6271-2020, 2020
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
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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.
Antonio Tovar-Sánchez, Araceli Rodríguez-Romero, Anja Engel, Birthe Zäncker, Franck Fu, Emilio Marañón, María Pérez-Lorenzo, Matthieu Bressac, Thibaut Wagener, Sylvain Triquet, Guillaume Siour, Karine Desboeufs, and Cécile Guieu
Biogeosciences, 17, 2349–2364, https://doi.org/10.5194/bg-17-2349-2020, https://doi.org/10.5194/bg-17-2349-2020, 2020
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Residence times of particulate metals derived from aerosol deposition in the Sea Surface Microlayer of the Mediterranean Sea ranged from a couple of minutes (e.g., for Fe) to a few hours (e.g., for Cu). Microbial activity seems to play an important role in in this process and in the concentration and distribution of metals between diferent water layers.
Laurent Menut, Guillaume Siour, Bertrand Bessagnet, Florian Couvidat, Emilie Journet, Yves Balkanski, and Karine Desboeufs
Geosci. Model Dev., 13, 2051–2071, https://doi.org/10.5194/gmd-13-2051-2020, https://doi.org/10.5194/gmd-13-2051-2020, 2020
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Modelling of mineral dust is often done using one single mean species. In this study, differentiated mineral species with their chemical composition are implemented in the CHIMERE regional chemistry-transport model by using global databases. Simulations are carried out to quantify the realism and gain of such mineralogy.
Patrick Chazette, Cyrille Flamant, Julien Totems, Marco Gaetani, Gwendoline Smith, Alexandre Baron, Xavier Landsheere, Karine Desboeufs, Jean-François Doussin, and Paola Formenti
Atmos. Chem. Phys., 19, 14979–15005, https://doi.org/10.5194/acp-19-14979-2019, https://doi.org/10.5194/acp-19-14979-2019, 2019
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Evolution of the vertical distribution and optical properties of aerosols in the free troposphere is analysed for the first time over the Namibian coast, a region where uncertainties on aerosol–cloud coupling in climate simulations are significant. The high variability of atmospheric aerosol composition is highlighted using a combination of ground-based, airborne and space-borne lidar. Aerosols are mainly transported from Angola, but part of the highest aerosol layer may come from South America.
Marc D. Mallet, Barbara D'Anna, Aurélie Même, Maria Chiara Bove, Federico Cassola, Giandomenico Pace, Karine Desboeufs, Claudia Di Biagio, Jean-Francois Doussin, Michel Maille, Dario Massabò, Jean Sciare, Pascal Zapf, Alcide Giorgio di Sarra, and Paola Formenti
Atmos. Chem. Phys., 19, 11123–11142, https://doi.org/10.5194/acp-19-11123-2019, https://doi.org/10.5194/acp-19-11123-2019, 2019
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We present findings from a summertime field campaign at the remote island of Lampedusa in the central Mediterranean Sea. We show that the aerosol loading is similar to coastal sites around the Mediterranean. We observe higher loadings of sulfate and aged organic aerosol from air masses transported over the central and eastern Mediterranean in comparison to those from the western Mediterranean. These results highlight the rarity of pristine air masses, even in remote marine environments.
David Au Yang, Pierre Cartigny, Karine Desboeufs, and David Widory
Atmos. Chem. Phys., 19, 3779–3796, https://doi.org/10.5194/acp-19-3779-2019, https://doi.org/10.5194/acp-19-3779-2019, 2019
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Sulfates present in urban aerosols collected worldwide usually exhibit 33S-anomalies whose origin remains unclear. Besides, the sulfate concentration is not very well modelled nowadays, which, coupled with the isotopic composition anomaly on the 33S, would highlight the presence of at least an additional oxidation pathway, different from O2+TMI, O3, OH, H2O2 and NO2. We suggest here the implication of two other possible oxidation pathways.
Paola Formenti, Stuart John Piketh, Andreas Namwoonde, Danitza Klopper, Roelof Burger, Mathieu Cazaunau, Anaïs Feron, Cécile Gaimoz, Stephen Broccardo, Nicola Walton, Karine Desboeufs, Guillaume Siour, Mattheus Hanghome, Samuel Mafwila, Edosa Omoregie, Wolfgang Junkermann, and Willy Maenhaut
Atmos. Chem. Phys., 18, 17003–17016, https://doi.org/10.5194/acp-18-17003-2018, https://doi.org/10.5194/acp-18-17003-2018, 2018
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Three-years of continuous measurements at the Henties Bay Aerosol Observatory (HBAO; 22°S, 14°05’E), Namibia, show that during the austral wintertime, long- and medium-range transport of pollution from biomass and fossil fuel burning give rise to peaks of light-absorbing black carbon aerosols into the marine boundary layer ahead of the main biomass burning season. This could affect the cloud properties.
Stelios Myriokefalitakis, Akinori Ito, Maria Kanakidou, Athanasios Nenes, Maarten C. Krol, Natalie M. Mahowald, Rachel A. Scanza, Douglas S. Hamilton, Matthew S. Johnson, Nicholas Meskhidze, Jasper F. Kok, Cecile Guieu, Alex R. Baker, Timothy D. Jickells, Manmohan M. Sarin, Srinivas Bikkina, Rachel Shelley, Andrew Bowie, Morgane M. G. Perron, and Robert A. Duce
Biogeosciences, 15, 6659–6684, https://doi.org/10.5194/bg-15-6659-2018, https://doi.org/10.5194/bg-15-6659-2018, 2018
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The first atmospheric iron (Fe) deposition model intercomparison is presented in this study, as a result of the deliberations of the United Nations Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP; http://www.gesamp.org/) Working Group 38. We conclude that model diversity over remote oceans reflects uncertainty in the Fe content parameterizations of dust aerosols, combustion aerosol emissions and the size distribution of transported aerosol Fe.
Audrey Gimenez, Melika Baklouti, Thibaut Wagener, and Thierry Moutin
Biogeosciences, 15, 6573–6589, https://doi.org/10.5194/bg-15-6573-2018, https://doi.org/10.5194/bg-15-6573-2018, 2018
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During the OUTPACE cruise conducted in the oligotrophic to ultra-oligotrophic region of the western tropical South Pacific, two contrasted regions were sampled in terms of N2 fixation rates, primary production rates and nutrient availability. The aim of this work was to investigate the role of N2 fixation in the differences observed between the two contrasted areas by comparing two simulations only differing by the presence or not of N2 fixers using a 1-D biogeochemical–physical coupled model.
Karine Desboeufs, Elisabeth Bon Nguyen, Servanne Chevaillier, Sylvain Triquet, and François Dulac
Atmos. Chem. Phys., 18, 14477–14492, https://doi.org/10.5194/acp-18-14477-2018, https://doi.org/10.5194/acp-18-14477-2018, 2018
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Atmospheric deposition is known to be a major source of nutrients for the marine biosphere in the Mediterranean Sea. The study of the origin of nutrients and trace metals in Corsica presented here shows that the dust events were the major sources of Si and Fe. Conversely, combustion sources predominated the inputs of N, P, and trace metals. This work showed the importance of considering background anthropogenic deposition for estimating the impact of atmospheric forcing on marine biota.
Kyle R. Frischkorn, Andreas Krupke, Cécile Guieu, Justine Louis, Mónica Rouco, Andrés E. Salazar Estrada, Benjamin A. S. Van Mooy, and Sonya T. Dyhrman
Biogeosciences, 15, 5761–5778, https://doi.org/10.5194/bg-15-5761-2018, https://doi.org/10.5194/bg-15-5761-2018, 2018
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Trichodesmium is a keystone genus of marine cyanobacteria that is estimated to supply nearly half of the ocean’s fixed nitrogen, fuelling primary productivity and the cycling of carbon and nitrogen in the ocean. In our study we characterize Trichodesmium ecology across the western tropical South Pacific using gene and genome sequencing and geochemistry. We detected genes for phosphorus reduction, providing a mechanism for the noted importance of this organism in the ocean's phosphorus cycle.
Thibaut Wagener, Nicolas Metzl, Mathieu Caffin, Jonathan Fin, Sandra Helias Nunige, Dominique Lefevre, Claire Lo Monaco, Gilles Rougier, and Thierry Moutin
Biogeosciences, 15, 5221–5236, https://doi.org/10.5194/bg-15-5221-2018, https://doi.org/10.5194/bg-15-5221-2018, 2018
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The western tropical South Pacific was sampled along a longitudinal 4000 km transect (OUTPACE cruise) for the measurement of carbonate parameters (total alkalinity and total inorganic carbon) between the Melanesian Archipelago and the western part of the South Pacific gyre. This paper reports this new dataset and derived properties. We also estimate anthropogenic carbon distribution in the water column using the TrOCA method.
Sophie Bonnet, Mathieu Caffin, Hugo Berthelot, Olivier Grosso, Mar Benavides, Sandra Helias-Nunige, Cécile Guieu, Marcus Stenegren, and Rachel Ann Foster
Biogeosciences, 15, 4215–4232, https://doi.org/10.5194/bg-15-4215-2018, https://doi.org/10.5194/bg-15-4215-2018, 2018
Thierry Moutin, Thibaut Wagener, Mathieu Caffin, Alain Fumenia, Audrey Gimenez, Melika Baklouti, Pascale Bouruet-Aubertot, Mireille Pujo-Pay, Karine Leblanc, Dominique Lefevre, Sandra Helias Nunige, Nathalie Leblond, Olivier Grosso, and Alain de Verneil
Biogeosciences, 15, 2961–2989, https://doi.org/10.5194/bg-15-2961-2018, https://doi.org/10.5194/bg-15-2961-2018, 2018
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Surface waters of the western tropical South Pacific were sampled along a longitudinal 4000 km transect during the stratified period between the Melanesian Archipelago and the western part of the South Pacific gyre. We found a significant biological carbon pump sustained almost exclusively by N2 fixation and essentially controlled by phosphate availability in the iron-rich Melanesian Archipelago waters which appears to be a net sink for atmospheric CO2 while the gyre is in a quasi-steady state.
Mathieu Caffin, Thierry Moutin, Rachel Ann Foster, Pascale Bouruet-Aubertot, Andrea Michelangelo Doglioli, Hugo Berthelot, Cécile Guieu, Olivier Grosso, Sandra Helias-Nunige, Nathalie Leblond, Audrey Gimenez, Anne Alexandra Petrenko, Alain de Verneil, and Sophie Bonnet
Biogeosciences, 15, 2565–2585, https://doi.org/10.5194/bg-15-2565-2018, https://doi.org/10.5194/bg-15-2565-2018, 2018
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We performed N budgets to assess the role of N2 fixation on production and export in the western tropical South Pacific Ocean. We deployed a combination of techniques including high-sensitivity measurements of N input and sediment traps deployment. We demonstrated that N2 fixation was the major source of new N before atmospheric deposition and upward nitrate fluxes. It contributed significantly to organic matter export, indicating a high efficiency of this region to export carbon.
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
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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.
Pierre Marrec, Gérald Grégori, Andrea M. Doglioli, Mathilde Dugenne, Alice Della Penna, Nagib Bhairy, Thierry Cariou, Sandra Hélias Nunige, Soumaya Lahbib, Gilles Rougier, Thibaut Wagener, and Melilotus Thyssen
Biogeosciences, 15, 1579–1606, https://doi.org/10.5194/bg-15-1579-2018, https://doi.org/10.5194/bg-15-1579-2018, 2018
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The objective of this study was to better understand the variability of the phytoplankton community structure in small physical structures at the surface of the ocean. After identifying such a structure in the Mediterranean Sea, we deployed cutting-edge physical and biological sensors in order to observe at a high frequency the dynamics of this structure. From these observations we described the variations of the phytoplankton community structure and how the physics controls this variability.
Yinghe Fu, Karine Desboeufs, Julie Vincent, Elisabeth Bon Nguyen, Benoit Laurent, Remi Losno, and François Dulac
Atmos. Meas. Tech., 10, 4389–4401, https://doi.org/10.5194/amt-10-4389-2017, https://doi.org/10.5194/amt-10-4389-2017, 2017
Angela N. Knapp, Sarah E. Fawcett, Alfredo Martínez-Garcia, Nathalie Leblond, Thierry Moutin, and Sophie Bonnet
Biogeosciences, 13, 4645–4657, https://doi.org/10.5194/bg-13-4645-2016, https://doi.org/10.5194/bg-13-4645-2016, 2016
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The goal of this manuscript was to track the fate of newly fixed nitrogen (N) in large volume mesocosms in the coastal waters of New Caledonia. We used a N isotope ("δ15N") budget and found a shift in the δ15N of sinking particulate N over the 23-day experiment, indicating that nitrate supported export production at the beginning of the experiment, but that nitrogen fixation supported export at the end. We infer that nitrogen fixation supported export production by a release of dissolved N.
Julie Vincent, Benoit Laurent, Rémi Losno, Elisabeth Bon Nguyen, Pierre Roullet, Stéphane Sauvage, Servanne Chevaillier, Patrice Coddeville, Noura Ouboulmane, Alcide Giorgio di Sarra, Antonio Tovar-Sánchez, Damiano Sferlazzo, Ana Massanet, Sylvain Triquet, Rafael Morales Baquero, Michel Fornier, Cyril Coursier, Karine Desboeufs, François Dulac, and Gilles Bergametti
Atmos. Chem. Phys., 16, 8749–8766, https://doi.org/10.5194/acp-16-8749-2016, https://doi.org/10.5194/acp-16-8749-2016, 2016
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To investigate dust deposition dynamics at the regional scale, five automatic deposition collectors named CARAGA have been deployed in the western Mediterranean basin (Lampedusa, Majorca, Corsica, Frioul and Le Casset) during 1 to 3 years depending on the station. Complementary observations provided by both satellite and air mass trajectories are used to identify the dust provenance areas and the transport pathways from the Sahara to the stations for the studied period.
M. Mallet, F. Dulac, P. Formenti, P. Nabat, J. Sciare, G. Roberts, J. Pelon, G. Ancellet, D. Tanré, F. Parol, C. Denjean, G. Brogniez, A. di Sarra, L. Alados-Arboledas, J. Arndt, F. Auriol, L. Blarel, T. Bourrianne, P. Chazette, S. Chevaillier, M. Claeys, B. D'Anna, Y. Derimian, K. Desboeufs, T. Di Iorio, J.-F. Doussin, P. Durand, A. Féron, E. Freney, C. Gaimoz, P. Goloub, J. L. Gómez-Amo, M. J. Granados-Muñoz, N. Grand, E. Hamonou, I. Jankowiak, M. Jeannot, J.-F. Léon, M. Maillé, S. Mailler, D. Meloni, L. Menut, G. Momboisse, J. Nicolas, T. Podvin, V. Pont, G. Rea, J.-B. Renard, L. Roblou, K. Schepanski, A. Schwarzenboeck, K. Sellegri, M. Sicard, F. Solmon, S. Somot, B Torres, J. Totems, S. Triquet, N. Verdier, C. Verwaerde, F. Waquet, J. Wenger, and P. Zapf
Atmos. Chem. Phys., 16, 455–504, https://doi.org/10.5194/acp-16-455-2016, https://doi.org/10.5194/acp-16-455-2016, 2016
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The aim of this article is to present an experimental campaign over the Mediterranean focused on aerosol-radiation measurements and modeling. Results indicate an important atmospheric loading associated with a moderate absorbing ability of mineral dust. Observations suggest a complex vertical structure and size distributions characterized by large aerosols within dust plumes. The radiative effect is highly variable, with negative forcing over the Mediterranean and positive over northern Africa.
Y. Zhang, N. Mahowald, R. A. Scanza, E. Journet, K. Desboeufs, S. Albani, J. F. Kok, G. Zhuang, Y. Chen, D. D. Cohen, A. Paytan, M. D. Patey, E. P. Achterberg, J. P. Engelbrecht, and K. W. Fomba
Biogeosciences, 12, 5771–5792, https://doi.org/10.5194/bg-12-5771-2015, https://doi.org/10.5194/bg-12-5771-2015, 2015
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A new technique to determine a size-fractionated global soil elemental emission inventory based on a global soil and mineralogical data set is introduced. Spatial variability of mineral dust elemental fractions (8 elements, e.g., Ca, Fe, Al) is identified on a global scale, particularly for Ca. The Ca/Al ratio ranged between 0.1 and 5.0 and is confirmed as an indicator of dust source regions by a global dust model. Total and soluble dust element fluxes into different ocean basins are estimated.
A. N. Schwier, C. Rose, E. Asmi, A. M. Ebling, W. M. Landing, S. Marro, M.-L. Pedrotti, A. Sallon, F. Iuculano, S. Agusti, A. Tsiola, P. Pitta, J. Louis, C. Guieu, F. Gazeau, and K. Sellegri
Atmos. Chem. Phys., 15, 7961–7976, https://doi.org/10.5194/acp-15-7961-2015, https://doi.org/10.5194/acp-15-7961-2015, 2015
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The effect of ocean acidification and changing water conditions on primary (and secondary) marine aerosol emissions is not well understood on a regional or a global scale. To investigate this effect, we deployed mesocosms in the Mediterranean Sea for several weeks during both winter pre-bloom and summer oligotrophic conditions and subjected them to various levels of CO2. We observed larger effects due to the differences between a pre-bloom and oligotrophic environment than due to CO2 levels.
H. Berthelot, T. Moutin, S. L'Helguen, K. Leblanc, S. Hélias, O. Grosso, N. Leblond, B. Charrière, and S. Bonnet
Biogeosciences, 12, 4099–4112, https://doi.org/10.5194/bg-12-4099-2015, https://doi.org/10.5194/bg-12-4099-2015, 2015
M. Rembauville, I. Salter, N. Leblond, A. Gueneugues, and S. Blain
Biogeosciences, 12, 3153–3170, https://doi.org/10.5194/bg-12-3153-2015, https://doi.org/10.5194/bg-12-3153-2015, 2015
E. Pulido-Villena, A.-C. Baudoux, I. Obernosterer, M. Landa, J. Caparros, P. Catala, C. Georges, J. Harmand, and C. Guieu
Biogeosciences, 11, 5607–5619, https://doi.org/10.5194/bg-11-5607-2014, https://doi.org/10.5194/bg-11-5607-2014, 2014
C. Guieu, C. Ridame, E. Pulido-Villena, M. Bressac, K. Desboeufs, and F. Dulac
Biogeosciences, 11, 5621–5635, https://doi.org/10.5194/bg-11-5621-2014, https://doi.org/10.5194/bg-11-5621-2014, 2014
P. Formenti, S. Caquineau, K. Desboeufs, A. Klaver, S. Chevaillier, E. Journet, and J. L. Rajot
Atmos. Chem. Phys., 14, 10663–10686, https://doi.org/10.5194/acp-14-10663-2014, https://doi.org/10.5194/acp-14-10663-2014, 2014
C. Ridame, J. Dekaezemacker, C. Guieu, S. Bonnet, S. L'Helguen, and F. Malien
Biogeosciences, 11, 4783–4800, https://doi.org/10.5194/bg-11-4783-2014, https://doi.org/10.5194/bg-11-4783-2014, 2014
M. Bressac, C. Guieu, D. Doxaran, F. Bourrin, K. Desboeufs, N. Leblond, and C. Ridame
Biogeosciences, 11, 1007–1020, https://doi.org/10.5194/bg-11-1007-2014, https://doi.org/10.5194/bg-11-1007-2014, 2014
C. Guieu, F. Dulac, C. Ridame, and P. Pondaven
Biogeosciences, 11, 425–442, https://doi.org/10.5194/bg-11-425-2014, https://doi.org/10.5194/bg-11-425-2014, 2014
C. Ridame, C. Guieu, and S. L'Helguen
Biogeosciences, 10, 7333–7346, https://doi.org/10.5194/bg-10-7333-2013, https://doi.org/10.5194/bg-10-7333-2013, 2013
R. Paris and K. V. Desboeufs
Atmos. Chem. Phys., 13, 4895–4905, https://doi.org/10.5194/acp-13-4895-2013, https://doi.org/10.5194/acp-13-4895-2013, 2013
V. Giovagnetti, C. Brunet, F. Conversano, F. Tramontano, I. Obernosterer, C. Ridame, and C. Guieu
Biogeosciences, 10, 2973–2991, https://doi.org/10.5194/bg-10-2973-2013, https://doi.org/10.5194/bg-10-2973-2013, 2013
K. Wuttig, T. Wagener, M. Bressac, A. Dammshäuser, P. Streu, C. Guieu, and P. L. Croot
Biogeosciences, 10, 2583–2600, https://doi.org/10.5194/bg-10-2583-2013, https://doi.org/10.5194/bg-10-2583-2013, 2013
Related subject area
Biogeochemistry: Air - Sea Exchange
Anomalous summertime CO2 sink in the subpolar Southern Ocean promoted by early 2021 sea ice retreat
Aerosol trace element solubility and deposition fluxes over the Mediterranean Sea and Black Sea basins
Variable organic matter stoichiometry enhances the biological drawdown of CO2 in the Northwest European shelf seas
Dimethyl sulfide (DMS) climatologies, fluxes, and trends – Part 1: Differences between seawater DMS estimations
Dimethyl sulfide (DMS) climatologies, fluxes, and trends – Part 2: Sea–air fluxes
Three-Compartment, Two Parameter, Concentration-Driven Model for Uptake of Excess Atmospheric CO2 by the Global Ocean
High-frequency continuous measurements reveal strong diel and seasonal cycling of pCO2 and CO2 flux in a mesohaline reach of the Chesapeake Bay
Significant role of physical transport in the marine carbon monoxide (CO) cycle: observations in the East Sea (Sea of Japan), the western North Pacific, and the Bering Sea in summer
Central Arctic Ocean surface–atmosphere exchange of CO2 and CH4 constrained by direct measurements
Spatial and seasonal variability in volatile organic sulfur compounds in seawater and the overlying atmosphere of the Bohai and Yellow seas
Estimating marine carbon uptake in the northeast Pacific using a neural network approach
Sea–air methane flux estimates derived from marine surface observations and instantaneous atmospheric measurements in the northern Labrador Sea and Baffin Bay
Global analysis of the controls on seawater dimethylsulfide spatial variability
Air–sea gas exchange in a seagrass ecosystem – results from a 3He ∕ SF6 tracer release experiment
Concentrations of dissolved dimethyl sulfide (DMS), methanethiol and other trace gases in context of microbial communities from the temperate Atlantic to the Arctic Ocean
Marine nitrogen fixation as a possible source of atmospheric water-soluble organic nitrogen aerosols in the subtropical North Pacific
Ice nucleating properties of the sea ice diatom Fragilariopsis cylindrus and its exudates
On physical mechanisms enhancing air–sea CO2 exchange
Winter season Southern Ocean distributions of climate-relevant trace gases
How biogenic polymers control surfactant dynamics in the surface microlayer: insights from a coastal Baltic Sea study
Identifying the biological control of the annual and multi-year variations in South Atlantic air–sea CO2 flux
The sensitivity of pCO2 reconstructions to sampling scales across a Southern Ocean sub-domain: a semi-idealized ocean sampling simulation approach
Physical mechanisms for biological carbon uptake during the onset of the spring phytoplankton bloom in the northwestern Mediterranean Sea (BOUSSOLE site)
Wintertime process study of the North Brazil Current rings reveals the region as a larger sink for CO2 than expected
New constraints on biological production and mixing processes in the South China Sea from triple isotope composition of dissolved oxygen
Tidal mixing of estuarine and coastal waters in the western English Channel is a control on spatial and temporal variability in seawater CO2
A seamless ensemble-based reconstruction of surface ocean pCO2 and air–sea CO2 fluxes over the global coastal and open oceans
Sea ice concentration impacts dissolved organic gases in the Canadian Arctic
Evaluating the Arabian Sea as a regional source of atmospheric CO2: seasonal variability and drivers
An empirical MLR for estimating surface layer DIC and a comparative assessment to other gap-filling techniques for ocean carbon time series
Derivation of seawater pCO2 from net community production identifies the South Atlantic Ocean as a CO2 source
Eukaryotic community composition in the sea surface microlayer across an east–west transect in the Mediterranean Sea
Enhancement of the North Atlantic CO2 sink by Arctic Waters
Global ocean dimethyl sulfide climatology estimated from observations and an artificial neural network
Atmospheric deposition of organic matter at a remote site in the central Mediterranean Sea: implications for the marine ecosystem
Underway seawater and atmospheric measurements of volatile organic compounds in the Southern Ocean
Dimethylsulfide (DMS), marine biogenic aerosols and the ecophysiology of coral reefs
Spatial variations in CO2 fluxes in the Saguenay Fjord (Quebec, Canada) and results of a water mixing model
Gas exchange estimates in the Peruvian upwelling regime biased by multi-day near-surface stratification
Insights from year-long measurements of air–water CH4 and CO2 exchange in a coastal environment
On the role of climate modes in modulating the air–sea CO2 fluxes in eastern boundary upwelling systems
Reviews and syntheses: the GESAMP atmospheric iron deposition model intercomparison study
Increase of dissolved inorganic carbon and decrease in pH in near-surface waters in the Mediterranean Sea during the past two decades
Utilizing the Drake Passage Time-series to understand variability and change in subpolar Southern Ocean pCO2
Effect of wind speed on the size distribution of gel particles in the sea surface microlayer: insights from a wind–wave channel experiment
The seasonal cycle of pCO2 and CO2 fluxes in the Southern Ocean: diagnosing anomalies in CMIP5 Earth system models
Marine phytoplankton stoichiometry mediates nonlinear interactions between nutrient supply, temperature, and atmospheric CO2
Interannual drivers of the seasonal cycle of CO2 in the Southern Ocean
Constraints on global oceanic emissions of N2O from observations and models
Arctic Ocean CO2 uptake: an improved multiyear estimate of the air–sea CO2 flux incorporating chlorophyll a concentrations
Kirtana Naëck, Jacqueline Boutin, Sebastiaan Swart, Marcel du Plessis, Liliane Merlivat, Laurence Beaumont, Antonio Lourenco, Francesco d'Ovidio, Louise Rousselet, Brian Ward, and Jean-Baptiste Sallée
Biogeosciences, 22, 1947–1968, https://doi.org/10.5194/bg-22-1947-2025, https://doi.org/10.5194/bg-22-1947-2025, 2025
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In summer 2022, a CARbon Interface OCean Atmosphere (CARIOCA) drifting buoy observed an anomalously strong ocean carbon sink in the subpolar Southern Ocean associated with large plumes of chlorophyll a. Lagrangian backward trajectories indicate that these waters originated from the sea ice edge in spring 2021. Our study highlights the northward migration of the CO2 sink associated with early sea ice retreat.
Rachel U. Shelley, Alex R. Baker, Max Thomas, and Sam Murphy
Biogeosciences, 22, 585–600, https://doi.org/10.5194/bg-22-585-2025, https://doi.org/10.5194/bg-22-585-2025, 2025
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The fractions of trace elements in atmospheric particles that are soluble have been measured over the Mediterranean and Black seas. These soluble fractions can affect the growth of microorganisms in the ocean, and our results show that they are affected by mixing with pollutants from the surrounding land and shipping emissions. Atmospheric particles contribute to the loads of soluble elements found in the surface waters and influence the balance between nitrogen and phosphorus.
Kubilay Timur Demir, Moritz Mathis, Jan Kossack, Feifei Liu, Ute Daewel, Christoph Stegert, Helmuth Thomas, and Corinna Schrum
EGUsphere, https://doi.org/10.5194/egusphere-2024-3449, https://doi.org/10.5194/egusphere-2024-3449, 2024
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This study examines how variations in the ratios of carbon, nitrogen and phosphorus in organic matter affect carbon cycling in the Northwest European shelf seas. Traditional models with fixed ratios tend to underestimate biological carbon uptake. By integrating variable ratios into a regional model, we find that carbon dioxide uptake increases by 10–33 %. These results highlight the need to include variable ratios for accurate assessments of regional and global carbon cycles.
Sankirna D. Joge, Anoop S. Mahajan, Shrivardhan Hulswar, Christa A. Marandino, Martí Galí, Thomas G. Bell, and Rafel Simó
Biogeosciences, 21, 4439–4452, https://doi.org/10.5194/bg-21-4439-2024, https://doi.org/10.5194/bg-21-4439-2024, 2024
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Dimethyl sulfide (DMS) is the largest natural source of sulfur in the atmosphere and leads to the formation of cloud condensation nuclei. DMS emission and quantification of its impacts have large uncertainties, but a detailed study on the emissions and drivers of their uncertainty is missing to date. The emissions are usually calculated from the seawater DMS concentrations and a flux parameterization. Here we quantify the differences in DMS seawater products, which can affect DMS fluxes.
Sankirna D. Joge, Anoop S. Mahajan, Shrivardhan Hulswar, Christa A. Marandino, Martí Galí, Thomas G. Bell, Mingxi Yang, and Rafel Simó
Biogeosciences, 21, 4453–4467, https://doi.org/10.5194/bg-21-4453-2024, https://doi.org/10.5194/bg-21-4453-2024, 2024
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Dimethyl sulfide (DMS) is the largest natural source of sulfur in the atmosphere and leads to the formation of cloud condensation nuclei. DMS emissions and quantification of their impacts have large uncertainties, but a detailed study on the range of emissions and drivers of their uncertainty is missing to date. The emissions are calculated from the seawater DMS concentrations and a flux parameterization. Here we quantify the differences in the effect of flux parameterizations used in models.
Stephen E. Schwartz
EGUsphere, https://doi.org/10.5194/egusphere-2024-2893, https://doi.org/10.5194/egusphere-2024-2893, 2024
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The net uptake coefficient of anthropogenic CO2 by the global ocean (net uptake flux divided by excess atmospheric CO2 stock above preindustrial) calculated with a simple, transparent, three-compartment concentration-driven model with two independent parameters is determined to be 0.010 ± 0.002 yr-1 (net uptake flux at year 2022 2.84 ± 0.6 Pg yr-1). This result compares well with observations and with much more complex carbon cycle models.
A. Whitman Miller, Jim R. Muirhead, Amanda C. Reynolds, Mark S. Minton, and Karl J. Klug
Biogeosciences, 21, 3717–3734, https://doi.org/10.5194/bg-21-3717-2024, https://doi.org/10.5194/bg-21-3717-2024, 2024
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High frequency pCO2 measurements reveal net neutral CO2 flux in a mesohaline reach of the Chesapeake Bay. Net off-gassing to the atmosphere begins in June when water temperatures rise above ~26ºC, continuing through November when temperatures fall below ~10ºC. Dissolved CO2 concentrations follow day–night cycles and are especially pronounced in warm waters. From December through May, the river is largely an uninterrupted sink for CO2 (i.e. CO2 is drawn out of the atmosphere into the river).
Young Shin Kwon, Tae Siek Rhee, Hyun-Cheol Kim, and Hyoun-Woo Kang
Biogeosciences, 21, 1847–1865, https://doi.org/10.5194/bg-21-1847-2024, https://doi.org/10.5194/bg-21-1847-2024, 2024
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Delving into CO dynamics from the East Sea to the Bering Sea, our study unveils the influence of physical transport on CO budgets. By measuring CO concentrations and parameters, we elucidate the interplay between biological and physical processes, highlighting the role of lateral transport in shaping CO distributions. Our findings underscore the importance of considering both biogeochemical and physical drivers in understanding marine carbon fluxes.
John Prytherch, Sonja Murto, Ian Brown, Adam Ulfsbo, Brett F. Thornton, Volker Brüchert, Michael Tjernström, Anna Lunde Hermansson, Amanda T. Nylund, and Lina A. Holthusen
Biogeosciences, 21, 671–688, https://doi.org/10.5194/bg-21-671-2024, https://doi.org/10.5194/bg-21-671-2024, 2024
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We directly measured methane and carbon dioxide exchange between ocean or sea ice and the atmosphere during an icebreaker-based expedition to the central Arctic Ocean (CAO) in summer 2021. These measurements can help constrain climate models and carbon budgets. The methane measurements, the first such made in the CAO, are lower than previous estimates and imply that the CAO is an insignificant contributor to Arctic methane emission. Gas exchange rates are slower than previous estimates.
Juan Yu, Lei Yu, Zhen He, Gui-Peng Yang, Jing-Guang Lai, and Qian Liu
Biogeosciences, 21, 161–176, https://doi.org/10.5194/bg-21-161-2024, https://doi.org/10.5194/bg-21-161-2024, 2024
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The distributions of volatile organic sulfur compounds (VSCs) (DMS, COS, and CS2) in the seawater and atmosphere of the Bohai and Yellow Seas were evaluated. Seasonal variations in VSCs were found and showed summer > spring. The COS concentrations exhibited positive correlation with DOC concentrations in seawater during summer. VSCs concentrations in seawater decreased with the depth. Sea-to-air fluxes of COS, DMS, and CS2 indicated that these marginal seas are sources of atmospheric VSCs.
Patrick J. Duke, Roberta C. Hamme, Debby Ianson, Peter Landschützer, Mohamed M. M. Ahmed, Neil C. Swart, and Paul A. Covert
Biogeosciences, 20, 3919–3941, https://doi.org/10.5194/bg-20-3919-2023, https://doi.org/10.5194/bg-20-3919-2023, 2023
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The ocean is both impacted by climate change and helps mitigate its effects through taking up carbon from the atmosphere. We used a machine learning approach to investigate what controls open-ocean carbon uptake in the northeast Pacific open ocean. Marine heatwaves that lasted 2–3 years increased uptake, while the upwelling strength of the Alaskan Gyre controlled uptake over 10-year time periods. The trend from 1998–2019 suggests carbon uptake in the northeast Pacific open ocean is increasing.
Judith Vogt, David Risk, Evelise Bourlon, Kumiko Azetsu-Scott, Evan N. Edinger, and Owen A. Sherwood
Biogeosciences, 20, 1773–1787, https://doi.org/10.5194/bg-20-1773-2023, https://doi.org/10.5194/bg-20-1773-2023, 2023
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The release of the greenhouse gas methane from Arctic submarine sources could exacerbate climate change in a positive feedback. Continuous monitoring of atmospheric methane levels over a 5100 km voyage in the western margin of the Labrador Sea and Baffin Bay revealed above-global averages likely affected by both onshore and offshore methane sources. Instantaneous sea–air methane fluxes were near zero at all measured stations, including a persistent cold-seep location.
George Manville, Thomas G. Bell, Jane P. Mulcahy, Rafel Simó, Martí Galí, Anoop S. Mahajan, Shrivardhan Hulswar, and Paul R. Halloran
Biogeosciences, 20, 1813–1828, https://doi.org/10.5194/bg-20-1813-2023, https://doi.org/10.5194/bg-20-1813-2023, 2023
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We present the first global investigation of controls on seawater dimethylsulfide (DMS) spatial variability over scales of up to 100 km. Sea surface height anomalies, density, and chlorophyll a help explain almost 80 % of DMS variability. The results suggest that physical and biogeochemical processes play an equally important role in controlling DMS variability. These data provide independent confirmation that existing parameterisations of seawater DMS concentration use appropriate variables.
Ryo Dobashi and David T. Ho
Biogeosciences, 20, 1075–1087, https://doi.org/10.5194/bg-20-1075-2023, https://doi.org/10.5194/bg-20-1075-2023, 2023
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Seagrass meadows are productive ecosystems and bury much carbon. Understanding their role in the global carbon cycle requires knowledge of air–sea CO2 fluxes and hence the knowledge of gas transfer velocity (k). In this study, k was determined from the dual tracer technique in Florida Bay. The observed gas transfer velocity was lower than previous studies in the coastal and open oceans at the same wind speeds, most likely due to wave attenuation by seagrass and limited wind fetch in this area.
Valérie Gros, Bernard Bonsang, Roland Sarda-Estève, Anna Nikolopoulos, Katja Metfies, Matthias Wietz, and Ilka Peeken
Biogeosciences, 20, 851–867, https://doi.org/10.5194/bg-20-851-2023, https://doi.org/10.5194/bg-20-851-2023, 2023
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The oceans are both sources and sinks for trace gases important for atmospheric chemistry and marine ecology. Here, we quantified selected trace gases (including the biological metabolites dissolved dimethyl sulfide, methanethiol and isoprene) along a 2500 km transect from the North Atlantic to the Arctic Ocean. In the context of phytoplankton and bacterial communities, our study suggests that methanethiol (rarely measured before) might substantially influence ocean–atmosphere cycling.
Tsukasa Dobashi, Yuzo Miyazaki, Eri Tachibana, Kazutaka Takahashi, Sachiko Horii, Fuminori Hashihama, Saori Yasui-Tamura, Yoko Iwamoto, Shu-Kuan Wong, and Koji Hamasaki
Biogeosciences, 20, 439–449, https://doi.org/10.5194/bg-20-439-2023, https://doi.org/10.5194/bg-20-439-2023, 2023
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Water-soluble organic nitrogen (WSON) in marine aerosols is important for biogeochemical cycling of bioelements. Our shipboard measurements suggested that reactive nitrogen produced and exuded by nitrogen-fixing microorganisms in surface seawater likely contributed to the formation of WSON aerosols in the subtropical North Pacific. This study provides new implications for the role of marine microbial activity in the formation of WSON aerosols in the ocean surface.
Lukas Eickhoff, Maddalena Bayer-Giraldi, Naama Reicher, Yinon Rudich, and Thomas Koop
Biogeosciences, 20, 1–14, https://doi.org/10.5194/bg-20-1-2023, https://doi.org/10.5194/bg-20-1-2023, 2023
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The formation of ice is an important process in Earth’s atmosphere, biosphere, and cryosphere, in particular in polar regions. Our research focuses on the influence of the sea ice diatom Fragilariopsis cylindrus and of molecules produced by it upon heterogenous ice nucleation. For that purpose, we studied the freezing of tiny droplets containing the diatoms in a microfluidic device. Together with previous studies, our results suggest a common freezing behaviour of various sea ice diatoms.
Lucía Gutiérrez-Loza, Erik Nilsson, Marcus B. Wallin, Erik Sahlée, and Anna Rutgersson
Biogeosciences, 19, 5645–5665, https://doi.org/10.5194/bg-19-5645-2022, https://doi.org/10.5194/bg-19-5645-2022, 2022
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The exchange of CO2 between the ocean and the atmosphere is an essential aspect of the global carbon cycle and is highly relevant for the Earth's climate. In this study, we used 9 years of in situ measurements to evaluate the temporal variability in the air–sea CO2 fluxes in the Baltic Sea. Furthermore, using this long record, we assessed the effect of atmospheric and water-side mechanisms controlling the efficiency of the air–sea CO2 exchange under different wind-speed conditions.
Li Zhou, Dennis Booge, Miming Zhang, and Christa A. Marandino
Biogeosciences, 19, 5021–5040, https://doi.org/10.5194/bg-19-5021-2022, https://doi.org/10.5194/bg-19-5021-2022, 2022
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Trace gas air–sea exchange exerts an important control on air quality and climate, especially in the Southern Ocean (SO). Almost all of the measurements there are skewed to summer, but it is essential to expand our measurement database over greater temporal and spatial scales. Therefore, we report measured concentrations of dimethylsulfide (DMS, as well as related sulfur compounds) and isoprene in the Atlantic sector of the SO. The observations of isoprene are the first in the winter in the SO.
Theresa Barthelmeß and Anja Engel
Biogeosciences, 19, 4965–4992, https://doi.org/10.5194/bg-19-4965-2022, https://doi.org/10.5194/bg-19-4965-2022, 2022
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Greenhouse gases released by human activity cause a global rise in mean temperatures. While scientists can predict how much of these gases accumulate in the atmosphere based on not only human-derived sources but also oceanic sinks, it is rather difficult to predict the major influence of coastal ecosystems. We provide a detailed study on the occurrence, composition, and controls of substances that suppress gas exchange. We thus help to determine what controls coastal greenhouse gas fluxes.
Daniel J. Ford, Gavin H. Tilstone, Jamie D. Shutler, and Vassilis Kitidis
Biogeosciences, 19, 4287–4304, https://doi.org/10.5194/bg-19-4287-2022, https://doi.org/10.5194/bg-19-4287-2022, 2022
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This study explores the seasonal, inter-annual, and multi-year drivers of the South Atlantic air–sea CO2 flux. Our analysis showed seasonal sea surface temperatures dominate in the subtropics, and the subpolar regions correlated with biological processes. Inter-annually, the El Niño–Southern Oscillation correlated with the CO2 flux by modifying sea surface temperatures and biological activity. Long-term trends indicated an important biological contribution to changes in the air–sea CO2 flux.
Laique M. Djeutchouang, Nicolette Chang, Luke Gregor, Marcello Vichi, and Pedro M. S. Monteiro
Biogeosciences, 19, 4171–4195, https://doi.org/10.5194/bg-19-4171-2022, https://doi.org/10.5194/bg-19-4171-2022, 2022
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Based on observing system simulation experiments using a mesoscale-resolving model, we found that to significantly improve uncertainties and biases in carbon dioxide (CO2) mapping in the Southern Ocean, it is essential to resolve the seasonal cycle (SC) of the meridional gradient of CO2 through high frequency (at least daily) observations that also span the region's meridional axis. We also showed that the estimated SC anomaly and mean annual CO2 are highly sensitive to seasonal sampling biases.
Liliane Merlivat, Michael Hemming, Jacqueline Boutin, David Antoine, Vincenzo Vellucci, Melek Golbol, Gareth A. Lee, and Laurence Beaumont
Biogeosciences, 19, 3911–3920, https://doi.org/10.5194/bg-19-3911-2022, https://doi.org/10.5194/bg-19-3911-2022, 2022
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We use in situ high-temporal-resolution measurements of dissolved inorganic carbon and atmospheric parameters at the air–sea interface to analyse phytoplankton bloom initiation identified as the net rate of biological carbon uptake in the Mediterranean Sea. The shift from wind-driven to buoyancy-driven mixing creates conditions for blooms to begin. Active mixing at the air–sea interface leads to the onset of the surface phytoplankton bloom due to the relaxation of wind speed following storms.
Léa Olivier, Jacqueline Boutin, Gilles Reverdin, Nathalie Lefèvre, Peter Landschützer, Sabrina Speich, Johannes Karstensen, Matthieu Labaste, Christophe Noisel, Markus Ritschel, Tobias Steinhoff, and Rik Wanninkhof
Biogeosciences, 19, 2969–2988, https://doi.org/10.5194/bg-19-2969-2022, https://doi.org/10.5194/bg-19-2969-2022, 2022
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We investigate the impact of the interactions between eddies and the Amazon River plume on the CO2 air–sea fluxes to better characterize the ocean carbon sink in winter 2020. The region is a strong CO2 sink, previously underestimated by a factor of 10 due to a lack of data and understanding of the processes responsible for the variability in ocean carbon parameters. The CO2 absorption is mainly driven by freshwater from the Amazon entrained by eddies and by the winter seasonal cooling.
Hana Jurikova, Osamu Abe, Fuh-Kwo Shiah, and Mao-Chang Liang
Biogeosciences, 19, 2043–2058, https://doi.org/10.5194/bg-19-2043-2022, https://doi.org/10.5194/bg-19-2043-2022, 2022
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We studied the isotopic composition of oxygen dissolved in seawater in the South China Sea. This tells us about the origin of oxygen in the water column, distinguishing between biological oxygen produced by phytoplankton communities and atmospheric oxygen entering seawater through gas exchange. We found that the East Asian Monsoon plays an important role in determining the amount of oxygen produced vs. consumed by the phytoplankton, as well as in inducing vertical water mass mixing.
Richard P. Sims, Michael Bedington, Ute Schuster, Andrew J. Watson, Vassilis Kitidis, Ricardo Torres, Helen S. Findlay, James R. Fishwick, Ian Brown, and Thomas G. Bell
Biogeosciences, 19, 1657–1674, https://doi.org/10.5194/bg-19-1657-2022, https://doi.org/10.5194/bg-19-1657-2022, 2022
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The amount of carbon dioxide (CO2) being absorbed by the ocean is relevant to the earth's climate. CO2 values in the coastal ocean and estuaries are not well known because of the instrumentation used. We used a new approach to measure CO2 across the coastal and estuarine zone. We found that CO2 and salinity were linked to the state of the tide. We used our CO2 measurements and model salinity to predict CO2. Previous studies overestimate how much CO2 the coastal ocean draws down at our site.
Thi Tuyet Trang Chau, Marion Gehlen, and Frédéric Chevallier
Biogeosciences, 19, 1087–1109, https://doi.org/10.5194/bg-19-1087-2022, https://doi.org/10.5194/bg-19-1087-2022, 2022
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Air–sea CO2 fluxes and associated uncertainty over the open ocean to coastal shelves are estimated with a new ensemble-based reconstruction of pCO2 trained on observation-based data. The regional distribution and seasonality of CO2 sources and sinks are consistent with those suggested in previous studies as well as mechanisms discussed therein. The ensemble-based uncertainty field allows identifying critical regions where improvements in pCO2 and air–sea CO2 flux estimates should be a priority.
Charel Wohl, Anna E. Jones, William T. Sturges, Philip D. Nightingale, Brent Else, Brian J. Butterworth, and Mingxi Yang
Biogeosciences, 19, 1021–1045, https://doi.org/10.5194/bg-19-1021-2022, https://doi.org/10.5194/bg-19-1021-2022, 2022
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We measured concentrations of five different organic gases in seawater in the high Arctic during summer. We found higher concentrations near the surface of the water column (top 5–10 m) and in areas of partial ice cover. This suggests that sea ice influences the concentrations of these gases. These gases indirectly exert a slight cooling effect on the climate, and it is therefore important to measure the levels accurately for future climate predictions.
Alain de Verneil, Zouhair Lachkar, Shafer Smith, and Marina Lévy
Biogeosciences, 19, 907–929, https://doi.org/10.5194/bg-19-907-2022, https://doi.org/10.5194/bg-19-907-2022, 2022
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The Arabian Sea is a natural CO2 source to the atmosphere, but previous work highlights discrepancies between data and models in estimating air–sea CO2 flux. In this study, we use a regional ocean model, achieve a flux closer to available data, and break down the seasonal cycles that impact it, with one result being the great importance of monsoon winds. As demonstrated in a meta-analysis, differences from data still remain, highlighting the great need for further regional data collection.
Jesse M. Vance, Kim Currie, John Zeldis, Peter W. Dillingham, and Cliff S. Law
Biogeosciences, 19, 241–269, https://doi.org/10.5194/bg-19-241-2022, https://doi.org/10.5194/bg-19-241-2022, 2022
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Long-term monitoring is needed to detect changes in our environment. Time series of ocean carbon have aided our understanding of seasonal cycles and provided evidence for ocean acidification. Data gaps are inevitable, yet no standard method for filling gaps exists. We present a regression approach here and compare it to seven other common methods to understand the impact of different approaches when assessing seasonal to climatic variability in ocean carbon.
Daniel J. Ford, Gavin H. Tilstone, Jamie D. Shutler, and Vassilis Kitidis
Biogeosciences, 19, 93–115, https://doi.org/10.5194/bg-19-93-2022, https://doi.org/10.5194/bg-19-93-2022, 2022
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This study identifies the most accurate biological proxy for the estimation of seawater pCO2 fields, which are key to assessing the ocean carbon sink. Our analysis shows that the net community production (NCP), the balance between photosynthesis and respiration, was more accurate than chlorophyll a within a neural network scheme. The improved pCO2 estimates, based on NCP, identified the South Atlantic Ocean as a net CO2 source, compared to a CO2 sink using chlorophyll a.
Birthe Zäncker, Michael Cunliffe, and Anja Engel
Biogeosciences, 18, 2107–2118, https://doi.org/10.5194/bg-18-2107-2021, https://doi.org/10.5194/bg-18-2107-2021, 2021
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Fungi are found in numerous marine environments. Our study found an increased importance of fungi in the Ionian Sea, where bacterial and phytoplankton counts were reduced, but organic matter was still available, suggesting fungi might benefit from the reduced competition from bacteria in low-nutrient, low-chlorophyll (LNLC) regions.
Jon Olafsson, Solveig R. Olafsdottir, Taro Takahashi, Magnus Danielsen, and Thorarinn S. Arnarson
Biogeosciences, 18, 1689–1701, https://doi.org/10.5194/bg-18-1689-2021, https://doi.org/10.5194/bg-18-1689-2021, 2021
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The Atlantic north of 50° N is an intense ocean sink area for atmospheric CO2. Observations in the vicinity of Iceland reveal a previously unrecognized Arctic contribution to the North Atlantic CO2 sink. Sustained CO2 influx to waters flowing from the Arctic Ocean is linked to their excess alkalinity derived from sources in the changing Arctic. The results relate to the following question: will the North Atlantic continue to absorb CO2 in the future as it has in the past?
Wei-Lei Wang, Guisheng Song, François Primeau, Eric S. Saltzman, Thomas G. Bell, and J. Keith Moore
Biogeosciences, 17, 5335–5354, https://doi.org/10.5194/bg-17-5335-2020, https://doi.org/10.5194/bg-17-5335-2020, 2020
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Dimethyl sulfide, a volatile compound produced as a byproduct of marine phytoplankton activity, can be emitted to the atmosphere via gas exchange. In the atmosphere, DMS is oxidized to cloud condensation nuclei, thus contributing to cloud formation. Therefore, oceanic DMS plays an important role in regulating the planet's climate by influencing the radiation budget. In this study, we use an artificial neural network model to update the global DMS climatology and estimate the sea-to-air flux.
Yuri Galletti, Silvia Becagli, Alcide di Sarra, Margherita Gonnelli, Elvira Pulido-Villena, Damiano M. Sferlazzo, Rita Traversi, Stefano Vestri, and Chiara Santinelli
Biogeosciences, 17, 3669–3684, https://doi.org/10.5194/bg-17-3669-2020, https://doi.org/10.5194/bg-17-3669-2020, 2020
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This paper reports the first data about atmospheric deposition of dissolved organic matter (DOM) on the island of Lampedusa. It also shows the implications for the surface marine layer by studying the impact of atmospheric organic carbon deposition in the marine ecosystem. It is a preliminary study, but it is pioneering and important for having new data that can be crucial in order to understand the impact of atmospheric deposition on the marine carbon cycle in a global climate change scenario.
Charel Wohl, Ian Brown, Vassilis Kitidis, Anna E. Jones, William T. Sturges, Philip D. Nightingale, and Mingxi Yang
Biogeosciences, 17, 2593–2619, https://doi.org/10.5194/bg-17-2593-2020, https://doi.org/10.5194/bg-17-2593-2020, 2020
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The oceans represent a poorly understood source of organic carbon to the atmosphere. In this paper, we present ship-based measurements of specific compounds in ambient air and seawater of the Southern Ocean. We present fluxes of these gases between air and sea at very high resolution. The data also contain evidence for day and night variations in some of these compounds. These measurements can be used to better understand the role of the Southern Ocean in the cycling of these compounds.
Rebecca L. Jackson, Albert J. Gabric, Roger Cropp, and Matthew T. Woodhouse
Biogeosciences, 17, 2181–2204, https://doi.org/10.5194/bg-17-2181-2020, https://doi.org/10.5194/bg-17-2181-2020, 2020
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Coral reefs are a strong source of atmospheric sulfur through stress-induced emissions of dimethylsulfide (DMS). This biogenic sulfur can influence aerosol and cloud properties and, consequently, the radiative balance over the ocean. DMS emissions may therefore help to mitigate coral physiological stress via increased low-level cloud cover and reduced sea surface temperature. The importance of DMS in coral physiology and climate is reviewed and the implications for coral bleaching are discussed.
Louise Delaigue, Helmuth Thomas, and Alfonso Mucci
Biogeosciences, 17, 547–566, https://doi.org/10.5194/bg-17-547-2020, https://doi.org/10.5194/bg-17-547-2020, 2020
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This paper reports on the first compilation and analysis of the surface water pCO2 distribution in the Saguenay Fjord, the southernmost subarctic fjord in the Northern Hemisphere, and thus fills a significant knowledge gap in current regional estimates of estuarine CO2 emissions.
Tim Fischer, Annette Kock, Damian L. Arévalo-Martínez, Marcus Dengler, Peter Brandt, and Hermann W. Bange
Biogeosciences, 16, 2307–2328, https://doi.org/10.5194/bg-16-2307-2019, https://doi.org/10.5194/bg-16-2307-2019, 2019
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We investigated air–sea gas exchange in oceanic upwelling regions for the case of nitrous oxide off Peru. In this region, routine concentration measurements from ships at 5 m or 10 m depth prove to overestimate surface (bulk) concentration. Thus, standard estimates of gas exchange will show systematic error. This is due to very shallow stratified layers that inhibit exchange between surface water and waters below and can exist for several days. Maximum bias occurs in moderate wind conditions.
Mingxi Yang, Thomas G. Bell, Ian J. Brown, James R. Fishwick, Vassilis Kitidis, Philip D. Nightingale, Andrew P. Rees, and Timothy J. Smyth
Biogeosciences, 16, 961–978, https://doi.org/10.5194/bg-16-961-2019, https://doi.org/10.5194/bg-16-961-2019, 2019
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We quantify the emissions and uptake of the greenhouse gases carbon dioxide and methane from the coastal seas of the UK over 1 year using the state-of-the-art eddy covariance technique. Our measurements show how these air–sea fluxes vary twice a day (tidal), diurnally (circadian) and seasonally. We also estimate the air–sea gas transfer velocity, which is essential for modelling and predicting coastal air-sea exchange.
Riley X. Brady, Nicole S. Lovenduski, Michael A. Alexander, Michael Jacox, and Nicolas Gruber
Biogeosciences, 16, 329–346, https://doi.org/10.5194/bg-16-329-2019, https://doi.org/10.5194/bg-16-329-2019, 2019
Stelios Myriokefalitakis, Akinori Ito, Maria Kanakidou, Athanasios Nenes, Maarten C. Krol, Natalie M. Mahowald, Rachel A. Scanza, Douglas S. Hamilton, Matthew S. Johnson, Nicholas Meskhidze, Jasper F. Kok, Cecile Guieu, Alex R. Baker, Timothy D. Jickells, Manmohan M. Sarin, Srinivas Bikkina, Rachel Shelley, Andrew Bowie, Morgane M. G. Perron, and Robert A. Duce
Biogeosciences, 15, 6659–6684, https://doi.org/10.5194/bg-15-6659-2018, https://doi.org/10.5194/bg-15-6659-2018, 2018
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The first atmospheric iron (Fe) deposition model intercomparison is presented in this study, as a result of the deliberations of the United Nations Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP; http://www.gesamp.org/) Working Group 38. We conclude that model diversity over remote oceans reflects uncertainty in the Fe content parameterizations of dust aerosols, combustion aerosol emissions and the size distribution of transported aerosol Fe.
Liliane Merlivat, Jacqueline Boutin, David Antoine, Laurence Beaumont, Melek Golbol, and Vincenzo Vellucci
Biogeosciences, 15, 5653–5662, https://doi.org/10.5194/bg-15-5653-2018, https://doi.org/10.5194/bg-15-5653-2018, 2018
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The fugacity of carbon dioxide in seawater (fCO2) was measured hourly in the surface waters of the NW Mediterranean Sea during two 3-year sequences separated by 18 years. A decrease of pH of 0.0022 yr−1 was computed. About 85 % of the accumulation of dissolved inorganic carbon (DIC) comes from chemical equilibration with increasing atmospheric CO2; the remaining 15 % accumulation is consistent with estimates of transfer of Atlantic waters through the Gibraltar Strait.
Amanda R. Fay, Nicole S. Lovenduski, Galen A. McKinley, David R. Munro, Colm Sweeney, Alison R. Gray, Peter Landschützer, Britton B. Stephens, Taro Takahashi, and Nancy Williams
Biogeosciences, 15, 3841–3855, https://doi.org/10.5194/bg-15-3841-2018, https://doi.org/10.5194/bg-15-3841-2018, 2018
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The Southern Ocean is highly under-sampled and since this region dominates the ocean sink for CO2, understanding change is critical. Here we utilize available observations to evaluate how the seasonal cycle, variability, and trends in surface ocean carbon in the well-sampled Drake Passage region compare to that of the broader subpolar Southern Ocean. Results indicate that the Drake Passage is representative of the broader region; however, additional winter observations would improve comparisons.
Cui-Ci Sun, Martin Sperling, and Anja Engel
Biogeosciences, 15, 3577–3589, https://doi.org/10.5194/bg-15-3577-2018, https://doi.org/10.5194/bg-15-3577-2018, 2018
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Biogenic gel particles such as transparent exopolymer particles (TEP) and Coomassie stainable particles (CSP) are important components in the sea-surface microlayer (SML). Their potential role in air–sea gas exchange and in primary organic aerosol emission has generated considerable research interest. Our wind wave channel experiment revealed how wind speed controls the accumulation and size distribution of biogenic gel particles in the SML.
N. Precious Mongwe, Marcello Vichi, and Pedro M. S. Monteiro
Biogeosciences, 15, 2851–2872, https://doi.org/10.5194/bg-15-2851-2018, https://doi.org/10.5194/bg-15-2851-2018, 2018
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Here we analyze seasonal cycle of CO2 biases in 10 CMIP5 models in the SO. We find two main model biases; exaggeration of primary production such that biologically driven DIC changes mainly regulates FCO2 variability, and an overestimation of the role of solubility, such that changes in temperature dominantly drive FCO2 seasonal changes to an extent of opposing biological CO2 uptake in spring. CMIP5 models show greater zonal homogeneity in the seasonal cycle of FCO2 than observational products.
Allison R. Moreno, George I. Hagstrom, Francois W. Primeau, Simon A. Levin, and Adam C. Martiny
Biogeosciences, 15, 2761–2779, https://doi.org/10.5194/bg-15-2761-2018, https://doi.org/10.5194/bg-15-2761-2018, 2018
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To bridge the missing links between variable marine elemental stoichiometry, phytoplankton physiology and carbon cycling, we embed four environmentally controlled stoichiometric models into a five-box ocean model. As predicted each model varied in its influence on the biological pump. Surprisingly, we found that variation can lead to nonlinear controls on atmospheric CO2 and carbon export, suggesting the need for further studies of ocean C : P and the impact on ocean carbon cycling.
Luke Gregor, Schalk Kok, and Pedro M. S. Monteiro
Biogeosciences, 15, 2361–2378, https://doi.org/10.5194/bg-15-2361-2018, https://doi.org/10.5194/bg-15-2361-2018, 2018
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The Southern Ocean accounts for a large portion of the variability in oceanic CO2 uptake. However, the drivers of these changes are not understood due to a lack of observations. In this study, we used an ensemble of gap-filling methods to estimate surface CO2. We found that winter was a more important driver of longer-term variability driven by changes in wind stress. Summer variability of CO2 was driven primarily by increases in primary production.
Erik T. Buitenhuis, Parvadha Suntharalingam, and Corinne Le Quéré
Biogeosciences, 15, 2161–2175, https://doi.org/10.5194/bg-15-2161-2018, https://doi.org/10.5194/bg-15-2161-2018, 2018
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Thanks to decreases in CFC concentrations, N2O is now the third-most important greenhouse gas, and the dominant contributor to stratospheric ozone depletion. Here we estimate the ocean–atmosphere N2O flux. We find that an estimate based on observations alone has a large uncertainty. By combining observations and a range of model simulations we find that the uncertainty is much reduced to 2.45 ± 0.8 Tg N yr−1, and better constrained and at the lower end of the estimate in the latest IPCC report.
Sayaka Yasunaka, Eko Siswanto, Are Olsen, Mario Hoppema, Eiji Watanabe, Agneta Fransson, Melissa Chierici, Akihiko Murata, Siv K. Lauvset, Rik Wanninkhof, Taro Takahashi, Naohiro Kosugi, Abdirahman M. Omar, Steven van Heuven, and Jeremy T. Mathis
Biogeosciences, 15, 1643–1661, https://doi.org/10.5194/bg-15-1643-2018, https://doi.org/10.5194/bg-15-1643-2018, 2018
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We estimated monthly air–sea CO2 fluxes in the Arctic Ocean and its adjacent seas north of 60° N from 1997 to 2014, after mapping pCO2 in the surface water using a self-organizing map technique. The addition of Chl a as a parameter enabled us to improve the estimate of pCO2 via better representation of its decline in spring. The uncertainty in the CO2 flux estimate was reduced, and a net annual Arctic Ocean CO2 uptake of 180 ± 130 Tg C y−1 was determined to be significant.
Cited articles
Averyt, K. B. and Paytan, A.: A comparison of multiple proxies for export production in the equatorial Pacific, Paleoceanog., 19, PA4003, https://doi.org/10.1029/2004pa001005, 2004.
Bergametti, G., Gomes, L., Remoudaki, E., Desbois, M., Martin, D., and Buat-Ménard, P.: Present transport and deposition patterns of African dusts to the north-western Mediterranean, in: Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport, edited by: M. Leinen and M. Sarnthein, Kluwer Academic Publishers, 227–251, 1989.
Bonnet, S. and Guieu, C.: Atmospheric forcing on the annual iron cycle in the western Mediterranean Sea: A 1-year survey, J. Geophys. Res., 111, C09010, https://doi.org/10.1029/2005JC003213, 2006.
Bory, A., Dulac, F., Moulin, C., Chiapello, I., Newton, P. P., Guelle, W., Lambert, C. E., and Bergametti, G.: Atmospheric and oceanic dust fluxes in the northeastern tropical Atlantic Ocean: How close a coupling?, Ann. Geophys., 20, 2067–2076, 2002.
Bressac, M. and Guieu, C.: Post-depositional processes: What really happens to new atmospheric iron in the ocean's surface?, Global Biogeochem. Cy., 27, 859–870, 2013.
Bressac, M., Guieu, C., Doxaran, D., Bourrin, F., Obolensky, G., and Grisoni, J. M.: A mesocosm experiment coupled with optical measurements to assess the fate and sinking of atmospheric particles in clear oligotrophic waters, Geochem. Mar. Lett., 32, 153–164, 2012.
Bressac, M., Guieu, C., Doxaran, D., Bourrin, F., Desboeufs, K., Leblond, N., and Ridame, C.: Quantification of the lithogenic carbon pump following a simulated dust-deposition event in large mesocosms, Biogeosciences, 11, 1007–1020, https://doi.org/10.5194/bg-11-1007-2014, 2014.
Buseck, P. R. and Posfai, M. l.: Airborne minerals and related aerosol particles: Effects on climate and the environment, Proc. Nat. Acad. Sci., 96, 3372–3379, 1999.
Desboeufs, K., Losno, R., Vimeux, F., and Cholbi, S.: pH dependent dissolution of wind transported Saharan dust, J. Geophys. Res., 104, 21287–21299, 1999.
Desboeufs, K. V., Losno, R., and Colin, J. L.: Factors influencing aerosol solubility during cloud processes, Atmos. Environ., 35, 3529–3537, 2001.
Fischer, G., Karakas, G., Blaas, M., Ratmeyer, V., Nowald, N., Schlitzer, R., Helmke, P., Davenport, R., Donner, B., Neuer, S., and Wefer, G.: Mineral ballast and particle settling rates in the coastal upwelling system off NW Africa and the South Atlantic, Int. J. Earth Sci., 98, 281–298, 2009.
Frigola, J., Moreno, A., Cacho, I., Canals, M., Sierro, F. J., Flores, J. A., Grimalt, J. O., Hodell, D. A., and Curtis, J. H.: Holocene climate variability in the western Mediterranean region from a deepwater sediment record, Paleoceanogr., 22, PA2209, https://doi.org/10.1029/2006pa001307, 2007.
Goutx, M., Momzikoff, M., Striby, L., Andersen, V., Marty, J.-C., and Vescovali, I.: High-frequency fluxes of labile compounds in the central Ligurian Sea, northwestern Mediterranean, Deep-Sea Res. I, 47, 533–556, 2000.
Govin, A., Holzwarth, U., Heslop, D., Ford Keeling, L., Zabel, M., Mulitza, S., Collins, J. A., and Chiessi, C. M.: Distribution of major elements in Atlantic surface sediments (36° N; 49°S): Imprint of terrigenous input and continental weathering, Geochem. Geophys. Geosyst., 13, Q01013, https://doi.org/10.1029/2011gc003785, 2012.
Guerzoni, S., Chester, R., Dulac, F., Herut, B., Loye-Pilot, M.-D., Measures, C., Migon, C., Molinaroli, E., Moulin, C., and Rossini, P.: The role of atmospheric deposition in the biogeochemistry of the Mediterranean Sea, Progr. Oceanogr., 44, 147–190, 1999.
Guieu, C., Dulac, F., Desboeufs, K., Wagener, T., Pulido-Villena, E., Grisoni, J. M., Louis, F., Ridame, C., Blain, S., Brunet, C., Bon Nguyen, E., Tran, S., Labiadh, M., and Dominici, J. M.: Large clean mesocosms and simulated dust deposition: a new methodology to investigate responses of marine oligotrophic ecosystems to atmospheric inputs, Biogeosciences, 7, 2765–2784, https://doi.org/10.5194/bg-7-2765-2010, 2010.
Guieu, C., Dulac, F., Ridame, C., and Pondaven, P.: Introduction to project DUNE, a DUst experiment in a low Nutrient, low chlorophyll Ecosystem, Biogeosci., 11, 425–442, 2014a.
Guieu, C., Ridame, C., Pulido-Villena, E., Bressac, M., Desboeufs, K., and Dulac, F.: Dust deposition in an oligotrophic marine environment: impact on the carbon budget, Biogeosci. Discuss., 11, 1707–1738, https://doi.org/10.5194/bgd-11-1707-2014, 2014b.
Heimbürger, A., Tharaud, M., Monna, F., Losno, R., Desboeufs, K., and Nguyen, E. B.: SLRS-5 Elemental Concentrations of Thirty-Three Uncertified Elements Deduced from SLRS-5/SLRS-4 Ratios, Geostand. Geoanal. Res., 37, 77–85, 2013.
Heimbürger, L.-E., Migon, C., Losno, R., Miquel, J.-C., Thibodeau, B., Stabholz, M., Dufour, A., and Leblond, N.: Vertical export flux of metals in the Mediterranean Sea, Deep-Sea Res. I, 87, 14–23, 2014.
Klaas, C. and D. E. Archer, Association of sinking organic matter with various types of mineral ballast in the deep sea: Implications for the rain ratio, Global Biogeochem. Cy., 16, 1116, https://doi.org/10.1029/2001GB001765, 2002.
Krom, M. D., Herut, B., and Mantoura, R. F. C.: Nutrient budget for the eastern Mediterranean: Implications for P limitation, Limnol. Oceanogr., 49, 1582–1592, 2004.
Lee, C., Peterson, M. L., Wakeham, S. G., Armstrong, R. A., Cochran, J. K., Miquel, J. C., Fowler, S. W., Hirschberg, D., Beck, A., and Xue, J.: Particulate organic matter and ballast fluxes measured using time-series and settling velocity sediment traps in the northwestern Mediterranean Sea, Deep-Sea Res. II, 56, 1420–1436, 2009.
Loÿe-Pilot, M. D., Martin, J. M., and Morelli, J.: Influence of Saharan dust on rain acidity and atmospheric input to the Mediterranean, Nature, 321, 427–428, 1986.
Mahiques, M. M., Wainer, I. E. K. C., Burone, L., Sousa, S. H. M. Silveira, I. C. A., Bícego, M. C., Alves, D. P., and Hammer, O.: A high-resolution Holocene record on the Southern Brazilian shelf: paleoenvironmental implications, Quat. Int., 206, 52–61, 2009.
Moreno, A., Cacho, I., Canals, M., Prins, M. A., Sánchez Goñi, M. F., Grimalt, J. O., and Weltje, G. J.: Saharan Dust Transport and High-Latitude Glacial Climatic Variability: The Alboran Sea Record, Quat. Res., 58, 318–328, 2002.
Mosseri, J., Quéguiner, B., Rimmelin, P., Leblond, N., and Guieu, C.: Silica fluxes in the northeast Atlantic frontal zone of Mode Water formation (38–45° N, 16–22° W) in 2001–2002, J. Geophys. Res., 110, C07S19, https://doi.org/10.1029/2004JC002615, 2005.
Neuer, S., Torres-Padro\'n, M. E., Gelado-Caballero, M. D., Rueda, M. J., Herna\'ndez-Brito, J., Davenport, R., and Wefer, G.: Dust deposition pulses to the eastern subtropical North Atlantic gyre: Does ocean's biogeochemistry respond?, Global Biogeochem. Cy., 18, GB4020, https://doi.org/10.1029/2004GB002228, 2004.
Paytan, A. and Kastner, M.: Benthic Ba fluxes in the central Equatorial Pacific, implications for the oceanic Ba cycle, Earth Planet. Sci. Lett., 142, 439–450, 1996.
Ploug, H., Iversen, M. H., and Fisher, G.: Ballast Sinking velocity, and apparent diffusivity within marine snow and zooplankton fecal pellets: implications for substrate turnover by attached bacteria. Limnol. Oceanogr., 53, 1878–1886, 2008.
Pulido-Villena, E., Rérolle, V., and Guieu, C.: Transient fertilizing effect of dust in P-deficient LNLC surface ocean, Geophys. Res. Lett., 37, L01603, 10.1029/2009gl041415, 2010.
Ridame, C., Guieu, C., and L'Helguen, S.: Strong stimulation of N2 fixation in oligotrophic Mediterranean Sea: results from dust addition in large in situ mesocosms, Biogeosciences, 10, 7333–7346, https://doi.org/10.5194/bg-10-7333-2013, 2013.
Ridame, C., Dekaezemacker, J., Guieu, C., Bonnet, S., L'Helguen, S., and Malien, F.: Phytoplanktonic response to contrasted Saharan dust deposition events during mesocosm experiments in LNLC environment, Biogeosci. Discuss., 11, 753–796, https://doi.org/10.5194/bgd-11-753-2014, 2014.
Sullivan, R. C., Guazzotti, S. A., Sodeman, D. A., and Prather, K. A.: Direct observations of the atmospheric processing of Asian mineral dust, Atmos. Chem. Phys., 7, 1213–1236, https://doi.org/10.5194/acp-7-1213-2007, 2007.
Sunda, W., G. and S. A. Huntsman: Cobalt and zinc interreplacement in marine phytoplankton: Biological and geochemical implications, Limnol. Oceanogr., 40, 1404–1417, 1995.
Ternon, E., Guieu, C., Loye-Pilot, M. D., Leblond, N., Bosc, E., Gasser, B., Miquel, J. C., and Martin, J.: The impact of Saharan dust on the particulate export in the water column of the North Western Mediterranean Sea, Biogeosciences, 7, 809–826, 2010.
Wagener, T., Guieu, C., and Leblond, N.: Effects of dust deposition on iron cycle in the surface Mediterranean Sea: results from a mesocosm seeding experiment, Biogeosciences, 7, 3769–3781, https://doi.org/10.5194/bg-7-3769-2010, 2010.
Wuttig, K., Wagener, T., Bressac, M., Dammshauser, A., Streu, P., Guieu, C., and Croot, P. L.: Impacts of dust deposition on dissolved trace metal concentrations (Mn, Al and Fe) during a mesocosm experiment, Biogeosciences, 10, 2583–2600, https://doi.org/10.5194/bg-10-2583-2013, 2013.
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