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2. Linkages Among Dissolved Organic Matter Export, Dissolved Metabolites, and Associated Microbial Community Structure Response in the Northwestern Sargasso Sea on a Seasonal Scale.

Author

Liu, Shuting, Longnecker, Krista, Kujawinski, Elizabeth, Vergin, Kevin, Bolaños, Luis, Giovannoni, Stephen, Parsons, Rachel, Opalk, Keri, Halewood, Elisa, Hansell, Dennis, Johnson, Rod, Curry, Ruth, and Carlson, Craig

Subjects
Sargasso Sea, amino acids, bacterioplankton, dissolved organic matter, metabolites, mixing, seasonal
Abstract

Deep convective mixing of dissolved and suspended organic matter from the surface to depth can represent an important export pathway of the biological carbon pump. The seasonally oligotrophic Sargasso Sea experiences annual winter convective mixing to as deep as 300 m, providing a unique model system to examine dissolved organic matter (DOM) export and its subsequent compositional transformation by microbial oxidation. We analyzed biogeochemical and microbial parameters collected from the northwestern Sargasso Sea, including bulk dissolved organic carbon (DOC), total dissolved amino acids (TDAA), dissolved metabolites, bacterial abundance and production, and bacterial community structure, to assess the fate and compositional transformation of DOM by microbes on a seasonal time-scale in 2016-2017. DOM dynamics at the Bermuda Atlantic Time-series Study site followed a general annual trend of DOC accumulation in the surface during stratified periods followed by downward flux during winter convective mixing. Changes in the amino acid concentrations and compositions provide useful indices of diagenetic alteration of DOM. TDAA concentrations and degradation indices increased in the mesopelagic zone during mixing, indicating the export of a relatively less diagenetically altered (i.e., more labile) DOM. During periods of deep mixing, a unique subset of dissolved metabolites, such as amino acids, vitamins, and benzoic acids, was produced or lost. DOM export and compositional change were accompanied by mesopelagic bacterial growth and response of specific bacterial lineages in the SAR11, SAR202, and SAR86 clades, Acidimicrobiales, and Flavobacteria, during and shortly following deep mixing. Complementary DOM biogeochemistry and microbial measurements revealed seasonal changes in DOM composition and diagenetic state, highlighting microbial alteration of the quantity and quality of DOM in the ocean.

Published
2022

3. Organic Matter Composition at Ocean Station Papa Affects Its Bioavailability, Bacterioplankton Growth Efficiency and the Responding Taxa.

Author

Stephens, Brandon, Opalk, Keri, Petras, Daniel, Liu, Shuting, Comstock, Jacqueline, Hansell, Dennis, Carlson, Craig, and Aluwihare, Lihini

Subjects
16S rDNA, LC-MS/MS, Ocean Station Papa, alpha diversity, bacterial growth efficiency, dissolved organic matter, organic matter remineralization, total hydrolyzable amino acids
Abstract

The bioavailability of organic matter (OM) to marine heterotrophic bacterioplankton is determined by both the chemical composition of OM and the microbial community composition. In the current study, changes in OM bioavailability were identified at Ocean Station Papa as part of the 2018 Export Processes in the Ocean from Remote Sensing (EXPORTS) field study. Removal rates of carbon (C) in controlled experiments were significantly correlated with the initial composition of total hydrolyzable amino acids, and C removal rates were high when the amino acid degradation index suggested a more labile composition. Carbon remineralization rates averaged 0.19 ± 0.08 μmol C L-1 d-1 over 6-10 days while bacterial growth efficiencies averaged 31 ± 7%. Amino acid composition and tandem mass spectrometry analysis of compound classes also revealed transformations to a more degraded OM composition during experiments. There was a log2-fold increase in the relative abundances of 16S rDNA-resolved bacterioplankton taxa in most experiments by members of the Methylophilaceae family (OM43 genus) and KI89A order. Additionally, when OM was more bioavailable, relative abundances increased by at least threefold for the classes Bacteroidetes (Flavobacteriaceae NS2b genus), Alphaproteobacteria (Rhodobacteraceae Sulfitobacter genus), and Gammaproteobacteria (Alteromonadales and Ectothiorhodospiraceae orders). Our data suggest that a diverse group of bacterioplankton was responsible for removing organic carbon and altering the OM composition to a more degraded state. Elevated community diversity, as inferred from the Shannon-Wiener H index, may have contributed to relatively high growth efficiencies by the bacterioplankton. The data presented here shed light on the interconnections between OM bioavailability and key bacterioplankton taxa for the degradation of marine OM.

Published
2021

4. Ocean carbon from space: Current status and priorities for the next decade

Author

Brewin, Robert J.W., Sathyendranath, Shubha, Kulk, Gemma, Rio, Marie-Hélène, Concha, Javier A., Bell, Thomas G., Bracher, Astrid, Fichot, Cédric, Frölicher, Thomas L., Galí, Martí, Hansell, Dennis Arthur, Kostadinov, Tihomir S., Mitchell, Catherine, Neeley, Aimee Renee, Organelli, Emanuele, Richardson, Katherine, Rousseaux, Cécile, Shen, Fang, Stramski, Dariusz, Tzortziou, Maria, Watson, Andrew J., Addey, Charles Izuma, Bellacicco, Marco, Bouman, Heather, Carroll, Dustin, Cetinić, Ivona, Dall’Olmo, Giorgio, Frouin, Robert, Hauck, Judith, Hieronymi, Martin, Hu, Chuanmin, Ibello, Valeria, Jönsson, Bror, Kong, Christina Eunjin, Kovač, Žarko, Laine, Marko, Lauderdale, Jonathan, Lavender, Samantha, Livanou, Eleni, Llort, Joan, Lorinczi, Larisa, Nowicki, Michael, Pradisty, Novia Arinda, Psarra, Stella, Raitsos, Dionysios E., Ruescas, Ana Belén, Russell, Joellen L., Salisbury, Joe, Sanders, Richard, Shutler, Jamie D., Sun, Xuerong, Taboada, Fernando González, Tilstone, Gavin H., Wei, Xinyuan, and Woolf, David K.

Published
2023
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8. Dissolved organic matter in the Arctic Ocean

Author

Hansell, Dennis A., Carlson, Craig A., Amon, Rainer M. W., Kaiser, Karl, Engel, Anja, Hansell, Dennis A., Carlson, Craig A., Amon, Rainer M. W., Kaiser, Karl, and Engel, Anja

Abstract

This chapter reviews and summarizes the state of the art of what we learned from the composition and distribution of dissolved organic matter (DOM) in the Arctic Ocean over the last few decades that were characterized by rapid climate change. Previous findings from the scientific literature are put in context to new insights by the authors. Most prominent features from this analysis include the wide spread occurrence of terrigenous DOM in the top ∼300 m of the Arctic Ocean with a broad band (∼1000 km wide) of elevated riverine DOM concentrations in the Transpolar Drift and the dominant role of physical processes, such as circulation and sea ice dynamics, for the pan-Arctic distribution of DOM. DOM also clearly tracks the brine fraction into the Arctic halocline, establishing DOM as a useful tracer for halocline formation. High uncertainty in DOC inflow and outflow estimates through the Arctic Ocean gateways makes a carbon mass balance difficult for the Arctic Ocean. Poor coverage of observations of primary production and especially respiration currently don’t allow for a clear determination if Arctic Ocean DOM represents a carbon sink or source for the subpolar ocean and the atmosphere.

Published
2024
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9. A global database of dissolved organic matter (DOM) concentration measurements in coastal waters (CoastDOM v1)

Author

Lønborg, Christian, Carreira, Cátia, Abril, Gwenaël, Agustí, Susana, Amaral, Valentina, Andersson, Agneta, Arístegui, Javier, Bhadury, Punyasloke, Bif, Mariana B., Borges, Alberto V., Bouillon, Steven, Calleja, Maria Ll., Cotovicz Jr., Luiz C., Cozzi, Stefano, Doval, Maryló, Duarte, Carlos M., Eyre, Bradley, Fichot, Cédric G., García-Martín, E. Elena, Garzon-Garcia, Alexandra, Giani, Michele, Gonçalves-Araujo, Rafael, Gruber, Renee, Hansell, Dennis A., Hashihama, Fuminori, He, Ding, Holding, Johnna M., Hunter, William R., Ibánhez, J. Severino P., Ibello, Valeria, Jiang, Shan, Kim, Guebuem, Klun, Katja, Kowalczuk, Piotr, Kubo, Atsushi, Lee, Choon-Weng, Lopes, Cláudia B., Maggioni, Federica, Magni, Paolo, Marrase, Celia, Martin, Patrick, McCallister, S. Leigh, McCallum, Roisin, Medeiros, Patricia M., Morán, Xosé Anxelu G., Muller-Karger, Frank E., Myers-Pigg, Allison, Norli, Marit, Oakes, Joanne M., Osterholz, Helena, Park, Hyukyung, Lund Paulsen, Maria, Rosentreter, Judith A., Ross, Jeff D., Rueda-Roa, Digna, Santinelli, Chiara, Shen, Yuan, Teira, Eva, Tinta, Tinkara, Uher, Guenther, Wakita, Masahide, Ward, Nicholas, Watanabe, Kenta, Xin, Yu, Yamashita, Youhei, Yang, Liyang, Yeo, Jacob, Yuan, Huamao, Zheng, Qiang, Álvarez-Salgado, Xosé Antón, Lønborg, Christian, Carreira, Cátia, Abril, Gwenaël, Agustí, Susana, Amaral, Valentina, Andersson, Agneta, Arístegui, Javier, Bhadury, Punyasloke, Bif, Mariana B., Borges, Alberto V., Bouillon, Steven, Calleja, Maria Ll., Cotovicz Jr., Luiz C., Cozzi, Stefano, Doval, Maryló, Duarte, Carlos M., Eyre, Bradley, Fichot, Cédric G., García-Martín, E. Elena, Garzon-Garcia, Alexandra, Giani, Michele, Gonçalves-Araujo, Rafael, Gruber, Renee, Hansell, Dennis A., Hashihama, Fuminori, He, Ding, Holding, Johnna M., Hunter, William R., Ibánhez, J. Severino P., Ibello, Valeria, Jiang, Shan, Kim, Guebuem, Klun, Katja, Kowalczuk, Piotr, Kubo, Atsushi, Lee, Choon-Weng, Lopes, Cláudia B., Maggioni, Federica, Magni, Paolo, Marrase, Celia, Martin, Patrick, McCallister, S. Leigh, McCallum, Roisin, Medeiros, Patricia M., Morán, Xosé Anxelu G., Muller-Karger, Frank E., Myers-Pigg, Allison, Norli, Marit, Oakes, Joanne M., Osterholz, Helena, Park, Hyukyung, Lund Paulsen, Maria, Rosentreter, Judith A., Ross, Jeff D., Rueda-Roa, Digna, Santinelli, Chiara, Shen, Yuan, Teira, Eva, Tinta, Tinkara, Uher, Guenther, Wakita, Masahide, Ward, Nicholas, Watanabe, Kenta, Xin, Yu, Yamashita, Youhei, Yang, Liyang, Yeo, Jacob, Yuan, Huamao, Zheng, Qiang, and Álvarez-Salgado, Xosé Antón

Abstract

Measurements of dissolved organic carbon (DOC), nitrogen (DON), and phosphorus (DOP) concentrations are used to characterize the dissolved organic matter (DOM) pool and are important components of biogeochemical cycling in the coastal ocean. Here, we present the first edition of a global database (CoastDOM v1; available at https://doi.org/10.1594/PANGAEA.964012, Lønborg et al., 2023) compiling previously published and unpublished measurements of DOC, DON, and DOP in coastal waters. These data are complemented by hydrographic data such as temperature and salinity and, to the extent possible, other biogeochemical variables (e.g. chlorophyll a, inorganic nutrients) and the inorganic carbon system (e.g. dissolved inorganic carbon and total alkalinity). Overall, CoastDOM v1 includes observations of concentrations from all continents. However, most data were collected in the Northern Hemisphere, with a clear gap in DOM measurements from the Southern Hemisphere. The data included were collected from 1978 to 2022 and consist of 62 338 data points for DOC, 20 356 for DON, and 13 533 for DOP. The number of measurements decreases progressively in the sequence DOC > DON > DOP, reflecting both differences in the maturity of the analytical methods and the greater focus on carbon cycling by the aquatic science community. The global database shows that the average DOC concentration in coastal waters (average ± standard deviation (SD): 182±314 µmol C L−1; median: 103 µmol C L−1) is 13-fold higher than the average coastal DON concentration (13.6±30.4 µmol N L−1; median: 8.0 µmol N L−1), which is itself 39-fold higher than the average coastal DOP concentration (0.34±1.11 µmol P L−1; median: 0.18 µmol P L−1). This dataset will be useful for identifying global spatial and temporal patterns in DOM and will help facilitate the reuse of DOC, DON, and DOP data in studies aimed at better characterizing local biogeochemic

Published
2024

17. A global database of dissolved organic matter (DOM) measurements in coastal waters (CoastDOM v1)

Author

Lønborg, Christian, primary, Carreira, Cátia, additional, Abril, Gwenaël, additional, Agustí, Susana, additional, Amaral, Valentina, additional, Andersson, Agneta, additional, Arístegui, Javier, additional, Bhadury, Punyasloke, additional, Bernardi Bif, Mariana, additional, Borges, Alberto V., additional, Bouillon, Steven, additional, Ll. Calleja, Maria, additional, Cotovicz Jr., Luiz C., additional, Cozzi, Stefano, additional, Doval, Maryló, additional, Duarte, Carlos M., additional, Eyre, Bradley, additional, Fichot, Cédric G., additional, García-Martín, E. Elena, additional, Garzon-Garcia, Alexandra, additional, Giani, Michele, additional, Gonçalves-Araujo, Rafael, additional, Gruber, Renee, additional, A. Hansell, Dennis, additional, Hashihama, Fuminori, additional, He, Ding, additional, Holding, Johnna M., additional, Hunter, William R., additional, Ibánhez, J. Severino P., additional, Ibello, Valeria, additional, Jiang, Shan, additional, Kim, Guebuem, additional, Klun, Katja, additional, Kowalczuk, Piotr, additional, Kubo, Atsushi, additional, Weng Lee, Choon, additional, Lopes, Cláudia B., additional, Maggioni, Federica, additional, Magni, Paolo, additional, Marrase, Celia, additional, Martin, Patrick, additional, McCallister, S. Leigh, additional, McCallum, Roisin, additional, Medeiros, Patricia M., additional, Morán, Xosé Anxelu G., additional, Muller-Karger, Frank, additional, Myers-Pigg, Allison, additional, Norli, Marit, additional, Oakes, Joanne M., additional, Osterholz, Helena, additional, Park, Hyekyung, additional, Lund Paulsen, Maria, additional, Rosentreter, Judith A., additional, Rueda-Roa, Digna, additional, Santinelli, Chiara, additional, Shen, Yuan, additional, Teira, Eva, additional, Tinta, Tinkara, additional, Uher, Guenther, additional, Wakita, Masahide, additional, Ward, Nicholas, additional, Watanabe, Kenta, additional, Xin, Yu, additional, Yamashita, Youhei, additional, Yang, Liyang, additional, Yeo, Jacob, additional, Yuan, Huamao, additional, Zheng, Qiang, additional, and Álvarez-Salgado, Xosé Antón, additional

Published
2023
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25. Ocean carbon from space: Current status and priorities for the next decade

Author

European Space Agency, Simons Foundation, National Centre for Earth Observation (UK), Swiss National Science Foundation, Agencia Estatal de Investigación (España), Brewin, Robert J. W., Sathyendranath, Shubha, Kulk, Gemma, Rio, Marie-Hélène, Concha, Javier A., Bell, Thomas G., Bracher, Astrid, Fichot, Cédric, Frölicher, Thomas, Galí, Martí, Hansell, Dennis A., Kostadinov, Tihomir, Mitchell, Catherine, Neeley, Aimee R., Organelli, Emanuele, Richardson, Katherine, Rousseaux, Cécile, Shen, Fang, Stramski, Dariusz, Tzortziou, Maria, Watson, Andrew J., Addey, Charles Izuma, Bellacicco, Marcos, Bouman, Heather A., Carroll, Dustin, Cetinić, Ivona, Dall'Olmo, Giorgio, Frouin, Robert, Hauck, Judith, Hieronymi, Martin, Hu, Chuanmin, Ibello, Valeria, Jönsson, Bror F., Kong, Christina Eunjin, Kovač, Žarko, Laine, Marko, Lauderdale, Jonathan, Lavender, Samantha, Livanou, Eleni, Llort, Joan, Lorinczi, Larisa, Nowicki, Michael, Pradisty, Novia Arinda, Psarra, Stella, Raitsos, Dionysios E., Ruescas, Ana Belén, Russell, Joellen L., Salisbury, Joe, Sanders, Richard J., Shutler, Jamie, Sun, Xuerong, González Taboada, Fernando, Tilstone, Gavin H., Wei, Xinyuan, Woolf, David K., European Space Agency, Simons Foundation, National Centre for Earth Observation (UK), Swiss National Science Foundation, Agencia Estatal de Investigación (España), Brewin, Robert J. W., Sathyendranath, Shubha, Kulk, Gemma, Rio, Marie-Hélène, Concha, Javier A., Bell, Thomas G., Bracher, Astrid, Fichot, Cédric, Frölicher, Thomas, Galí, Martí, Hansell, Dennis A., Kostadinov, Tihomir, Mitchell, Catherine, Neeley, Aimee R., Organelli, Emanuele, Richardson, Katherine, Rousseaux, Cécile, Shen, Fang, Stramski, Dariusz, Tzortziou, Maria, Watson, Andrew J., Addey, Charles Izuma, Bellacicco, Marcos, Bouman, Heather A., Carroll, Dustin, Cetinić, Ivona, Dall'Olmo, Giorgio, Frouin, Robert, Hauck, Judith, Hieronymi, Martin, Hu, Chuanmin, Ibello, Valeria, Jönsson, Bror F., Kong, Christina Eunjin, Kovač, Žarko, Laine, Marko, Lauderdale, Jonathan, Lavender, Samantha, Livanou, Eleni, Llort, Joan, Lorinczi, Larisa, Nowicki, Michael, Pradisty, Novia Arinda, Psarra, Stella, Raitsos, Dionysios E., Ruescas, Ana Belén, Russell, Joellen L., Salisbury, Joe, Sanders, Richard J., Shutler, Jamie, Sun, Xuerong, González Taboada, Fernando, Tilstone, Gavin H., Wei, Xinyuan, and Woolf, David K.

Abstract

The ocean plays a central role in modulating the Earth’s carbon cycle. Monitoring how the ocean carbon cycle is changing is fundamental to managing climate change. Satellite remote sensing is currently our best tool for viewing the ocean surface globally and systematically, at high spatial and temporal resolutions, and the past few decades have seen an exponential growth in studies utilising satellite data for ocean carbon research. Satellite-based observations must be combined with in-situ observations and models, to obtain a comprehensive view of ocean carbon pools and fluxes. To help prioritise future research in this area, a workshop was organised that assembled leading experts working on the topic, from around the world, including remote-sensing scientists, field scientists and modellers, with the goal to articulate a collective view of the current status of ocean carbon research, identify gaps in knowledge, and formulate a scientific roadmap for the next decade, with an emphasis on evaluating where satellite remote sensing may contribute. A total of 449 scientists and stakeholders participated (with balanced gender representation), from North and South America, Europe, Asia, Africa, and Oceania. Sessions targeted both inorganic and organic pools of carbon in the ocean, in both dissolved and particulate form, as well as major fluxes of carbon between reservoirs (e.g., primary production) and at interfaces (e.g., air-sea and land–ocean). Extreme events, blue carbon and carbon budgeting were also key topics discussed. Emerging priorities identified include: expanding the networks and quality of in-situ observations; improved satellite retrievals; improved uncertainty quantification; improved understanding of vertical distributions; integration with models; improved techniques to bridge spatial and temporal scales of the different data sources; and improved fundamental understanding of the ocean carbon cycle, and of the interactions among pools of carbon and light

Published
2023

26. Ocean carbon from space:Current status and priorities for the next decade

Author

Brewin, Robert J. W., Sathyendranath, Shubha, Kulk, Gemma, Rio, Marie Hélène, Concha, Javier A., Bell, Thomas G., Bracher, Astrid, Fichot, Cédric, Frölicher, Thomas L., Galí, Martí, Hansell, Dennis Arthur, Kostadinov, Tihomir S., Mitchell, Catherine, Neeley, Aimee Renee, Organelli, Emanuele, Richardson, Katherine, Rousseaux, Cécile, Shen, Fang, Stramski, Dariusz, Tzortziou, Maria, Watson, Andrew J., Addey, Charles Izuma, Bellacicco, Marco, Bouman, Heather, Carroll, Dustin, Cetinić, Ivona, Dall'Olmo, Giorgio, Frouin, Robert, Hauck, Judith, Hieronymi, Martin, Hu, Chuanmin, Ibello, Valeria, Jönsson, Bror, Kong, Christina Eunjun, Kovač, Žarko, Laine, Marko, Lauderdale, Jonathan, Lavender, Samantha, Livanou, Eleni, Llort, Joan, Lorinczi, Larisa, Nowicki, Michael, Pradisty, Novia Arinda, Psarra, Stella, Raitsos, Dionysios E., Ruescas, Ana Belén, Russell, Joellen L., Salisbury, Joe, Sanders, Richard, Shutler, Jamie D., Sun, Xuerong, Taboada, Fernando González, Tilstone, Gavin H., Wei, Xinyuan, Woolf, David K., Brewin, Robert J. W., Sathyendranath, Shubha, Kulk, Gemma, Rio, Marie Hélène, Concha, Javier A., Bell, Thomas G., Bracher, Astrid, Fichot, Cédric, Frölicher, Thomas L., Galí, Martí, Hansell, Dennis Arthur, Kostadinov, Tihomir S., Mitchell, Catherine, Neeley, Aimee Renee, Organelli, Emanuele, Richardson, Katherine, Rousseaux, Cécile, Shen, Fang, Stramski, Dariusz, Tzortziou, Maria, Watson, Andrew J., Addey, Charles Izuma, Bellacicco, Marco, Bouman, Heather, Carroll, Dustin, Cetinić, Ivona, Dall'Olmo, Giorgio, Frouin, Robert, Hauck, Judith, Hieronymi, Martin, Hu, Chuanmin, Ibello, Valeria, Jönsson, Bror, Kong, Christina Eunjun, Kovač, Žarko, Laine, Marko, Lauderdale, Jonathan, Lavender, Samantha, Livanou, Eleni, Llort, Joan, Lorinczi, Larisa, Nowicki, Michael, Pradisty, Novia Arinda, Psarra, Stella, Raitsos, Dionysios E., Ruescas, Ana Belén, Russell, Joellen L., Salisbury, Joe, Sanders, Richard, Shutler, Jamie D., Sun, Xuerong, Taboada, Fernando González, Tilstone, Gavin H., Wei, Xinyuan, and Woolf, David K.

Abstract

The ocean plays a central role in modulating the Earth’s carbon cycle. Monitoring how the ocean carbon cycle is changing is fundamental to managing climate change. Satellite remote sensing is currently our best tool for viewing the ocean surface globally and systematically, at high spatial and temporal resolutions, and the past few decades have seen an exponential growth in studies utilising satellite data for ocean carbon research. Satellite-based observations must be combined with in-situ observations and models, to obtain a comprehensive view of ocean carbon pools and fluxes. To help prioritise future research in this area, a workshop was organised that assembled leading experts working on the topic, from around the world, including remote-sensing scientists, field scientists and modellers, with the goal to articulate a collective view of the current status of ocean carbon research, identify gaps in knowledge, and formulate a scientific roadmap for the next decade, with an emphasis on evaluating where satellite remote sensing may contribute. A total of 449 scientists and stakeholders participated (with balanced gender representation), from North and South America, Europe, Asia, Africa, and Oceania. Sessions targeted both inorganic and organic pools of carbon in the ocean, in both dissolved and particulate form, as well as major fluxes of carbon between reservoirs (e.g., primary production) and at interfaces (e.g., air-sea and land–ocean). Extreme events, blue carbon and carbon budgeting were also key topics discussed. Emerging priorities identified include: expanding the networks and quality of in-situ observations; improved satellite retrievals; improved uncertainty quantification; improved understanding of vertical distributions; integration with models; improved techniques to bridge spatial and temporal scales of the different data sources; and improved fundamental understanding of the ocean carbon cycle, and of the interactions among pools of carbon and light, The ocean plays a central role in modulating the Earth's carbon cycle. Monitoring how the ocean carbon cycle is changing is fundamental to managing climate change. Satellite remote sensing is currently our best tool for viewing the ocean surface globally and systematically, at high spatial and temporal resolutions, and the past few decades have seen an exponential growth in studies utilising satellite data for ocean carbon research. Satellite-based observations must be combined with in-situ observations and models, to obtain a comprehensive view of ocean carbon pools and fluxes. To help prioritise future research in this area, a workshop was organised that assembled leading experts working on the topic, from around the world, including remote-sensing scientists, field scientists and modellers, with the goal to articulate a collective view of the current status of ocean carbon research, identify gaps in knowledge, and formulate a scientific roadmap for the next decade, with an emphasis on evaluating where satellite remote sensing may contribute. A total of 449 scientists and stakeholders participated (with balanced gender representation), from North and South America, Europe, Asia, Africa, and Oceania. Sessions targeted both inorganic and organic pools of carbon in the ocean, in both dissolved and particulate form, as well as major fluxes of carbon between reservoirs (e.g., primary production) and at interfaces (e.g., air-sea and land–ocean). Extreme events, blue carbon and carbon budgeting were also key topics discussed. Emerging priorities identified include: expanding the networks and quality of in-situ observations; improved satellite retrievals; improved uncertainty quantification; improved understanding of vertical distributions; integration with models; improved techniques to bridge spatial and temporal scales of the different data sources; and improved fundamental understanding of the ocean carbon cycle, and of the interactions among pools of carbon and li

Published
2023

30. Oxygen, Carbon and pH Variability in the Indian Ocean

Author

Hood, Raleigh, Rixen, Tim, Lévy, Marina, Hansell, Dennis, Coles, Victoria, Lachkar, Zouhair, Processus et interactions de fine échelle océanique (PROTEO), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)

Subjects
[SDE]Environmental Sciences
Abstract

International audience; This chapter provides an overview of the physical and biogeochemical factors that control spatial and temporal patterns of oxygen minimum zones (OMZs), carbon and pH variability in the Indian Ocean. Oxygen concentrations decline to nearly zero in Arabian Sea intermediate water with profound biogeochemical impacts on the nitrogen cycle as a result of denitrification. These impacts can hardly be observed in the Bay of Bengal where oxygen concentrations are poised just above the threshold below which denitrification becomes significant. Hypoxic/anoxic conditions in the open ocean waters of the northern Indian Ocean have not dramatically changed over past decades, but evidence is now emerging that oxygen concentrations are starting to decline, with significant biogeochemical and ecological impacts. The Indian Ocean accounts for ~1/5 of the global oceanic uptake of atmospheric CO2, with the Arabian Sea as a source of CO2 to the atmosphere and the southern subtropical gyre as a CO2 sink. Net CO2 flux in the Bay of Bengal is uncertain due to sparse sampling. Surface pH values in the Indian Ocean are anomalously low and projected to decline further with negative impacts on calcifying organisms. Dissolved organic carbon (DOC) concentrations in the Indian Ocean tend to be high in nearsurface (sub)tropical waters where autotrophic production of DOC exceeds heterotrophic consumption and vertical stability of the water column favors accumulation. In contrast, the highest particulate organic carbon (POC) concentrations in the Indian Ocean are observed in the northwestern part of the basin and the lowest in the southern subtropical gyre, reflecting primary production patterns. POC export flux patterns in the Indian Ocean are similar to the patterns in POC concentration, though carbon flux is also strongly influenced by lithogenic matter content in river-influenced regions like the Bay of Bengal. Observational and modeling research should target improved understanding of northern Indian Ocean OMZ and carbon system variability as such is needed to predict the impacts of anthropogenic influence and global warming on Indian Ocean biogeochemistry and ecosystems.

Published
2023

33. Spatial Complexity in Dissolved Organic Matter and Trace Elements Driven by Hydrography and Freshwater Input Across the Arctic Ocean During 2015 Arctic GEOTRACES Expeditions

Author

Williford, Tatiana, primary, Amon, Rainer M. W., additional, Kaiser, Karl, additional, Benner, Ronald, additional, Stedmon, Colin, additional, Bauch, Dorothea, additional, Fitzsimmons, Jessica N., additional, Gerringa, Loes J. A., additional, Newton, Robert, additional, Hansell, Dennis A., additional, Granskog, Mats A., additional, Jensen, Laramie, additional, Laglera, Luis M., additional, Pasqualini, Angelica, additional, Rabe, Benjamin, additional, Reader, Heather, additional, Rutgers van der Loeff, Michiel, additional, and Yan, Ge, additional

Published
2022
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37. EXPORTS Measurements and Protocols for the NE Pacific Campaign

Author

Behrenfeld, Michael J., Benitez-Nelson, Claudia R., Boss, Emmanuel S., Brzezinski, Mark A., Buck, Kristen N., Buesseler, Ken O., Burd, Adrian B., Carlson, Craig A., Cassar, Nicolas, Cetinić, Ivona, Close, Hilary G., Craig, Susanne E., D'Asaro, Eric A., Durkin, Colleen A., Estapa, Margaret L., Fassbender, Andrea, Fox, James, Freeman, Scott, Gifford, Scott M., Gong, Weida, Graff, Jason R., Gray, Deric, Guidi, Lionel, Halsey, Kim, Hansell, Dennis A., Haëntjens, Nils, Horner, Tristan J., Jenkins, Bethany D., Jones, Janice L., Karp-Boss, Lee, Kramer, Sasha J., Lam, Phoebe J., Lee, Craig M., Lee, Jong-Mi, Liu, Shuting, Mannino, Antonio, Maas, Amy E., Marchal, Olivier, Marchetti, Adrian, McDonnell, Andrew M. P., McNair, Heather, Menden-Deuer, Susanne, Morison, Francoise, Nelson, Norman B., Nicholson, David P., Niebergall, Alexandria K., Omand, Melissa M., Passow, Uta, Perry, Mary J., Popp, Brian N., Proctor, Chris, Rafter, Patrick, Roca-Martí, Montserrat, Roesler, Collin S., Rubin, Edwina, Rynearson, Tatiana A., Santoro, Alyson E., Siegel, David A., Sosik, Heidi M., Soto Ramos, Inia, Stamieszkin, Karen, Steinberg, Deborah K., Stephens, Brandon M., Thompson, Andrew F., Van Mooy, Benjamin A. S., Zhang, Xiaodong, Behrenfeld, Michael J., Benitez-Nelson, Claudia R., Boss, Emmanuel S., Brzezinski, Mark A., Buck, Kristen N., Buesseler, Ken O., Burd, Adrian B., Carlson, Craig A., Cassar, Nicolas, Cetinić, Ivona, Close, Hilary G., Craig, Susanne E., D'Asaro, Eric A., Durkin, Colleen A., Estapa, Margaret L., Fassbender, Andrea, Fox, James, Freeman, Scott, Gifford, Scott M., Gong, Weida, Graff, Jason R., Gray, Deric, Guidi, Lionel, Halsey, Kim, Hansell, Dennis A., Haëntjens, Nils, Horner, Tristan J., Jenkins, Bethany D., Jones, Janice L., Karp-Boss, Lee, Kramer, Sasha J., Lam, Phoebe J., Lee, Craig M., Lee, Jong-Mi, Liu, Shuting, Mannino, Antonio, Maas, Amy E., Marchal, Olivier, Marchetti, Adrian, McDonnell, Andrew M. P., McNair, Heather, Menden-Deuer, Susanne, Morison, Francoise, Nelson, Norman B., Nicholson, David P., Niebergall, Alexandria K., Omand, Melissa M., Passow, Uta, Perry, Mary J., Popp, Brian N., Proctor, Chris, Rafter, Patrick, Roca-Martí, Montserrat, Roesler, Collin S., Rubin, Edwina, Rynearson, Tatiana A., Santoro, Alyson E., Siegel, David A., Sosik, Heidi M., Soto Ramos, Inia, Stamieszkin, Karen, Steinberg, Deborah K., Stephens, Brandon M., Thompson, Andrew F., Van Mooy, Benjamin A. S., and Zhang, Xiaodong

Abstract

EXport Processes in the Ocean from Remote Sensing (EXPORTS) is a large-scale NASA-led and NSF co-funded field campaign that will provide critical information for quantifying the export and fate of upper ocean net primary production (NPP) using satellite information and state of the art technology.

Published
2022

38. Spatial complexity in dissolved organic matter and trace elements driven by hydrography and freshwater input across the Arctic Ocean during 2015 Arctic GEOTRACES expeditions

Author

Williford, Tatiana, Amon, Rainer M.W., Kaiser, Karl, Benner, Ronald, Stedmon, Colin, Bauch, Dorothea, Fitzsimmons, Jessica N., Gerringa, Loes J.A., Newton, Robert, Hansell, Dennis A., Granskog, Mats A., Jensen, Laramie, Laglera, Luis M., Pasqualini, Angelica, Rabe, Benjamin, Reader, Heather, van der Rutgers Loeff, Michiel, Yan, Ge, Williford, Tatiana, Amon, Rainer M.W., Kaiser, Karl, Benner, Ronald, Stedmon, Colin, Bauch, Dorothea, Fitzsimmons, Jessica N., Gerringa, Loes J.A., Newton, Robert, Hansell, Dennis A., Granskog, Mats A., Jensen, Laramie, Laglera, Luis M., Pasqualini, Angelica, Rabe, Benjamin, Reader, Heather, van der Rutgers Loeff, Michiel, and Yan, Ge

Abstract

This study traces dissolved organic matter (DOM) in different water masses of the Arctic Ocean and its effect on the distributions of trace elements (TEs; Fe, Cu, Mn, Ni, Zn, Cd) using fluorescent properties of DOM and the terrigenous biomarker lignin. The Nansen, Amundsen, and Makarov Basins were characterized by the influence of Atlantic water and the fluvial discharge of the Siberian rivers with high concentrations of terrigenous DOM (tDOM). The Canada Basin and the Chukchi Sea were characterized by Pacific water, modified through contact with productive shelf sediments with elevated levels of marine DOM. Within the surface layer of the Beaufort Gyre, meteoric water (river water and precipitation) was characterized by low concentrations of lignin and terrigenous DOM fluorescence proxies as DOM is removed during freezing. High-resolution in situ fluorescence profiles revealed that DOM distribution closely followed isopycnals, indicating the strong influence of sea-ice formation and melt, which was also reflected in strong correlations between DOM fluorescence and brine contributions. The relationship of DOM and hydrography to TEs showed that terrigenous and marine DOM were likely carriers of dissolved Fe, Ni, Cu from the Eurasian shelves into the central Arctic Ocean. Chukchi shelf sediments were important sources of dCd, dZn, and dNi, as well as marine ligands that bind and carry these TEs offshore within the upper halocline (UHC) in the Canada Basin. Our data suggest that tDOM components represent stronger ligands relative to marine DOM components, potentially facilitating the long-range transport of TE to the North Atlantic. Key Points Dissolved Organic Matter (DOM) distribution in the Arctic Ocean is largely controlled by sea ice formation and melt processes DOM distribution in the Arctic Ocean reveals its potential as a tracer for halocline formation and freshwater source assignments Terrigenous and marine DOM are carriers of trace elements from shelves to th

Published
2022
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39. The Transpolar Drift as a Source of Riverine and Shelf‐Derived Trace Elements to the Central Arctic Ocean

Author

Massachusetts Institute of Technology. Center for Global Change Science, Charette, Matthew A., Kipp, Lauren E., Jensen, Laramie T., Dabrowski, Jessica S., Whitmore, Laura M., Fitzsimmons, Jessica N., Williford, Tatiana, Ulfsbo, Adam, Jones, Elizabeth, Bundy, Randelle M., Vivancos, Sebastian M., Pahnke, Katharina, John, Seth G., Xiang, Yang, Hatta, Mariko, Petrova, Mariia V., Heimbürger‐Boavida, Lars‐Eric, Bauch, Dorothea, Newton, Robert, Pasqualini, Angelica, Agather, Alison M., Amon, Rainer M. W., Anderson, Robert F., Andersson, Per S., Benner, Ronald, Bowman, Katlin L., Edwards, R. Lawrence, Gdaniec, Sandra, Gerringa, Loes J. A., González, Aridane G., Granskog, Mats, Haley, Brian, Hammerschmidt, Chad R., Hansell, Dennis A., Henderson, Paul B., Kadko, David C., Kaiser, Karl, Laan, Patrick, Lam, Phoebe J., Lamborg, Carl H., Levier, Martin, Li, Xianglei, Margolin, Andrew R., Measures, Chris, Middag, Rob, Millero, Frank J., Moore, Willard S., Paffrath, Ronja, Planquette, Hélène, Rabe, Benjamin, Reader, Heather, Rember, Robert, Rijkenberg, Micha J. A., Roy‐Barman, Matthieu, Rutgers van der Loeff, Michiel, Saito, Mak, Schauer, Ursula, Schlosser, Peter, Sherrell, Robert M., Shiller, Alan M., Slagter, Hans, Sonke, Jeroen E., Stedmon, Colin, Woosley, Ryan J., Valk, Ole, Ooijen, Jan, Zhang, Ruifeng, Massachusetts Institute of Technology. Center for Global Change Science, Charette, Matthew A., Kipp, Lauren E., Jensen, Laramie T., Dabrowski, Jessica S., Whitmore, Laura M., Fitzsimmons, Jessica N., Williford, Tatiana, Ulfsbo, Adam, Jones, Elizabeth, Bundy, Randelle M., Vivancos, Sebastian M., Pahnke, Katharina, John, Seth G., Xiang, Yang, Hatta, Mariko, Petrova, Mariia V., Heimbürger‐Boavida, Lars‐Eric, Bauch, Dorothea, Newton, Robert, Pasqualini, Angelica, Agather, Alison M., Amon, Rainer M. W., Anderson, Robert F., Andersson, Per S., Benner, Ronald, Bowman, Katlin L., Edwards, R. Lawrence, Gdaniec, Sandra, Gerringa, Loes J. A., González, Aridane G., Granskog, Mats, Haley, Brian, Hammerschmidt, Chad R., Hansell, Dennis A., Henderson, Paul B., Kadko, David C., Kaiser, Karl, Laan, Patrick, Lam, Phoebe J., Lamborg, Carl H., Levier, Martin, Li, Xianglei, Margolin, Andrew R., Measures, Chris, Middag, Rob, Millero, Frank J., Moore, Willard S., Paffrath, Ronja, Planquette, Hélène, Rabe, Benjamin, Reader, Heather, Rember, Robert, Rijkenberg, Micha J. A., Roy‐Barman, Matthieu, Rutgers van der Loeff, Michiel, Saito, Mak, Schauer, Ursula, Schlosser, Peter, Sherrell, Robert M., Shiller, Alan M., Slagter, Hans, Sonke, Jeroen E., Stedmon, Colin, Woosley, Ryan J., Valk, Ole, Ooijen, Jan, and Zhang, Ruifeng

Published
2022

42. Eddy/Wind Interactions Stimulate Extraordinary Mid-Ocean Plankton Blooms

Author

McGillicuddy, Dennis J., Anderson, Laurence A., Bates, Nicholas R., Bibby, Thomas, Buesseler, Ken O., Carlson, Craig A., Davis, Cabell S., Ewart, Courtney, Falkowski, Paul G., Goldthwait, Sarah A., Hansell, Dennis A., Jenkins, William J., Johnson, Rodney, Kosnyrev, Valery K., Ledwell, James R., Li, Qian P., Siegel, David A., and Steinberg, Deborah K.

Published
2007
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43. Linkages Among Dissolved Organic Matter Export, Dissolved Metabolites, and Associated Microbial Community Structure Response in the Northwestern Sargasso Sea on a Seasonal Scale

Author

Liu, Shuting, primary, Longnecker, Krista, additional, Kujawinski, Elizabeth B., additional, Vergin, Kevin, additional, Bolaños, Luis M., additional, Giovannoni, Stephen J., additional, Parsons, Rachel, additional, Opalk, Keri, additional, Halewood, Elisa, additional, Hansell, Dennis A., additional, Johnson, Rod, additional, Curry, Ruth, additional, and Carlson, Craig A., additional

Published
2022
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44. Assessing the apparent imbalance between geochemical and biochemical indicators of meso- and bathypelagic biological activity: What the @$♯! is wrong with present calculations of carbon budgets?

Author

Burd, Adrian B., Hansell, Dennis A., Steinberg, Deborah K., Anderson, Thomas R., Arístegui, Javier, Baltar, Federico, Beaupré, Steven R., Buesseler, Ken O., DeHairs, Frank, Jackson, George A., Kadko, David C., Koppelmann, Rolf, Lampitt, Richard S., Nagata, Toshi, Reinthaler, Thomas, Robinson, Carol, Robison, Bruce H., Tamburini, Christian, and Tanaka, Tsuneo

Published
2010
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45. Emerging concepts on microbial processes in the bathypelagic ocean – ecology, biogeochemistry, and genomics

Author

Nagata, Toshi, Tamburini, Christian, Arístegui, Javier, Baltar, Federico, Bochdansky, Alexander B., Fonda-Umani, Serena, Fukuda, Hideki, Gogou, Alexandra, Hansell, Dennis A., Hansman, Roberta L., Herndl, Gerhard J., Panagiotopoulos, Christos, Reinthaler, Thomas, Sohrin, Rumi, Verdugo, Pedro, Yamada, Namiha, Yamashita, Youhei, Yokokawa, Taichi, and Bartlett, Douglas H.

Published
2010
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50. Contributors

Author

Abdulla, Hussain A.N., Aluwihare, Lihini, Amon, Rainer M.W., Björkman, Karin M., Bronk, Deborah A., Buck, Kristen N., Bundy, Randelle M., Burdige, David J., Carlson, Craig A., Dai, Minhan, DeVries, Timothy, Dittmar, Thorsten, Engel, Anja, English, Chance J., Giovannoni, Stephen, Halsey, Kimberly H., Hansell, Dennis A., Kaiser, Karl, Karl, David M., Kido Soule, Melissa C., Kieber, David J., Komada, Tomoko, Kujawinski, Elizabeth B., Lang, Susan Q., Lee, Cindy, Lennartz, Sinikka T., Letscher, Robert T., Levine, Naomi M., Li, Xiaolin, Liu, Shuting, Longnecker, Krista, Lopez, Chelsea N., McCarthy, Matthew D., Meng, Feifei, Miller, William L., Padaki, Vaishnavi G., Powers, Leanne C., Raymond, Peter A., Repeta, Daniel, Romera-Castillo, Cristina, Sipler, Rachel E., Spencer, Robert G.M., Stedmon, Colin A., Stephens, Brandon M., Stubbins, Aron, Wang, Zhixuan, Yamashita, Youhei, and Zhang, Yao

Published
2024
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