Articles | Volume 21, issue 6
https://doi.org/10.5194/os-21-3123-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-21-3123-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Blank variability in coulometric measurements of dissolved inorganic carbon
Matthew P. Humphreys
CORRESPONDING AUTHOR
Department of Ocean Systems, NIOZ Royal Netherlands Institute for Sea Research, P.O. Box 59, 1790 AB Den Burg (Texel), the Netherlands
Sharyn Ossebaar
Department of Ocean Systems, NIOZ Royal Netherlands Institute for Sea Research, P.O. Box 59, 1790 AB Den Burg (Texel), the Netherlands
Related authors
Yasmina Ourradi, Gert-Jan Reichart, Sonja van Leeuwen, and Matthew Humphreys
EGUsphere, https://doi.org/10.5194/egusphere-2025-5050, https://doi.org/10.5194/egusphere-2025-5050, 2025
This preprint is open for discussion and under review for Biogeosciences (BG).
Short summary
Short summary
We measured pH at high frequency for nearly a year at the Wadden Sea-North Sea interface. Biological activity mainly controls daily pH variations, while water exchange affects alkalinity. Dissolved inorganic carbon is influenced by both processes. Our research shows the Wadden Sea releases CO2 to the atmosphere. Understanding these patterns is crucial for predicting how coastal seas respond to changing climate and water conditions.
Ben A. Cala, Mariette Wolthers, Olivier Sulpis, Jonathan D. Sharp, and Matthew P. Humphreys
EGUsphere, https://doi.org/10.5194/egusphere-2025-5059, https://doi.org/10.5194/egusphere-2025-5059, 2025
This preprint is open for discussion and under review for Ocean Science (OS).
Short summary
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Magnesium calcites are minerals produced by some marine organisms. Understanding how these minerals dissolve helps us to predict how the ocean stores carbon. We developed a new method to calculate the solubility of these minerals in seawater, using existing laboratory data and taking into account the effects of temperature, salinity and pressure. Applying this method globally, we found that magnesium calcites dissolve deeper than previously thought.
Louise Delaigue, Gert-Jan Reichart, Li Qiu, Eric P. Achterberg, Yasmina Ourradi, Chris Galley, André Mutzberg, and Matthew P. Humphreys
Biogeosciences, 22, 5103–5121, https://doi.org/10.5194/bg-22-5103-2025, https://doi.org/10.5194/bg-22-5103-2025, 2025
Short summary
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Our study analysed pH in ocean surface waters to understand how it fluctuates with changes in temperature, salinity, and biological activities. We found that temperature mainly controls daily pH variations, but biological processes also play a role, especially in affecting CO2 levels between the ocean and atmosphere. Our research shows how these factors together maintain the balance of ocean chemistry, which is crucial for predicting changes in marine environments.
Anne L. Kruijt, Robin van Dijk, Olivier Sulpis, Luc Beaufort, Guillaume Lassus, Geert-Jan Brummer, A. Daniëlle van der Burg, Ben A. Cala, Yasmina Ourradi, Katja T. C. A. Peijnenburg, Matthew P. Humphreys, Sonia Chaabane, Appy Sluijs, and Jack J. Middelburg
EGUsphere, https://doi.org/10.5194/egusphere-2025-4234, https://doi.org/10.5194/egusphere-2025-4234, 2025
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We measured the three main types of plankton that produce calcium carbonate in the ocean, at the same time and location. While coccolithophores were the biggest contributors, we found that planktonic gastropods, not foraminifera, were the second largest contributor. This challenges the current view and improves our understanding of how these organisms influence oceans’ carbon cycling.
Hinne Florian van der Zant, Olivier Sulpis, Jack J. Middelburg, Matthew P. Humphreys, Raphaël Savelli, Dustin Carroll, Dimitris Menemenlis, Kay Sušelj, and Vincent Le Fouest
EGUsphere, https://doi.org/10.5194/egusphere-2025-2244, https://doi.org/10.5194/egusphere-2025-2244, 2025
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We developed a model to simulate seafloor biogeochemical processes across a wide range of marine environments, from shallow coastal zones to deep-sea sediments. From this model, we derived a set of simple equations that predict how carbon, oxygen, and alkalinity are exchanged between sediments and overlying waters. These equations provide an efficient way to improve how ocean models represent seafloor interactions, which are often missing or overly simplified.
Li-Qing Jiang, Amanda Fay, Jens Daniel Müller, Lydia Keppler, Dustin Carroll, Siv K. Lauvset, Tim DeVries, Judith Hauck, Christian Rödenbeck, Luke Gregor, Nicolas Metzl, Andrea J. Fassbender, Jean-Pierre Gattuso, Peter Landschützer, Rik Wanninkhof, Christopher Sabine, Simone R. Alin, Mario Hoppema, Are Olsen, Matthew P. Humphreys, Kumiko Azetsu-Scott, Dorothee C. E. Bakker, Leticia Barbero, Nicholas R. Bates, Nicole Besemer, Henry C. Bittig, Albert E. Boyd, Daniel Broullón, Wei-Jun Cai, Brendan R. Carter, Thi-Tuyet-Trang Chau, Chen-Tung Arthur Chen, Frédéric Cyr, John E. Dore, Ian Enochs, Richard A. Feely, Hernan E. Garcia, Marion Gehlen, Lucas Gloege, Melchor González-Dávila, Nicolas Gruber, Yosuke Iida, Masao Ishii, Esther Kennedy, Alex Kozyr, Nico Lange, Claire Lo Monaco, Derek P. Manzello, Galen A. McKinley, Natalie M. Monacci, Xose A. Padin, Ana M. Palacio-Castro, Fiz F. Pérez, Alizée Roobaert, J. Magdalena Santana-Casiano, Jonathan Sharp, Adrienne Sutton, Jim Swift, Toste Tanhua, Maciej Telszewski, Jens Terhaar, Ruben van Hooidonk, Anton Velo, Andrew J. Watson, Angelicque E. White, Zelun Wu, Hyelim Yoo, and Jiye Zeng
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-255, https://doi.org/10.5194/essd-2025-255, 2025
Preprint under review for ESSD
Short summary
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This review article provides an overview of 60 existing ocean carbonate chemistry data products, encompassing a broad range of types, including compilations of cruise datasets, gap-filled observational products, model simulations, and more. It is designed to help researchers identify and access the data products that best support their scientific objectives, thereby facilitating progress in understanding the ocean's changing carbonate chemistry.
Matthew P. Humphreys
Ocean Sci., 20, 1325–1350, https://doi.org/10.5194/os-20-1325-2024, https://doi.org/10.5194/os-20-1325-2024, 2024
Short summary
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The ocean takes up carbon dioxide (CO2) from the atmosphere, slowing climate change. This CO2 uptake is controlled by a property called ƒCO2. Seawater ƒCO2 changes as seawater warms or cools, although by an uncertain amount; measurements and calculations give inconsistent results. Here, we work out how ƒCO2 should, in theory, respond to temperature. This matches field data and model calculations but still has discrepancies with scarce laboratory results, which need more measurements to resolve.
Siv K. Lauvset, Nico Lange, Toste Tanhua, Henry C. Bittig, Are Olsen, Alex Kozyr, Marta Álvarez, Kumiko Azetsu-Scott, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Mario Hoppema, Matthew P. Humphreys, Masao Ishii, Emil Jeansson, Akihiko Murata, Jens Daniel Müller, Fiz F. Pérez, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Adam Ulfsbo, Anton Velo, Ryan J. Woosley, and Robert M. Key
Earth Syst. Sci. Data, 16, 2047–2072, https://doi.org/10.5194/essd-16-2047-2024, https://doi.org/10.5194/essd-16-2047-2024, 2024
Short summary
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GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv2.2023 is the fifth update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality controlling, including systematic evaluation of measurement biases. This version contains data from 1108 hydrographic cruises covering the world's oceans from 1972 to 2021.
Siv K. Lauvset, Nico Lange, Toste Tanhua, Henry C. Bittig, Are Olsen, Alex Kozyr, Simone Alin, Marta Álvarez, Kumiko Azetsu-Scott, Leticia Barbero, Susan Becker, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Richard A. Feely, Mario Hoppema, Matthew P. Humphreys, Masao Ishii, Emil Jeansson, Li-Qing Jiang, Steve D. Jones, Claire Lo Monaco, Akihiko Murata, Jens Daniel Müller, Fiz F. Pérez, Benjamin Pfeil, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Bronte Tilbrook, Adam Ulfsbo, Anton Velo, Ryan J. Woosley, and Robert M. Key
Earth Syst. Sci. Data, 14, 5543–5572, https://doi.org/10.5194/essd-14-5543-2022, https://doi.org/10.5194/essd-14-5543-2022, 2022
Short summary
Short summary
GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv2.2022 is the fourth update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality controlling, including systematic evaluation of measurement biases. This version contains data from 1085 hydrographic cruises covering the world's oceans from 1972 to 2021.
Olivier Sulpis, Matthew P. Humphreys, Monica M. Wilhelmus, Dustin Carroll, William M. Berelson, Dimitris Menemenlis, Jack J. Middelburg, and Jess F. Adkins
Geosci. Model Dev., 15, 2105–2131, https://doi.org/10.5194/gmd-15-2105-2022, https://doi.org/10.5194/gmd-15-2105-2022, 2022
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A quarter of the surface of the Earth is covered by marine sediments rich in calcium carbonates, and their dissolution acts as a giant antacid tablet protecting the ocean against human-made acidification caused by massive CO2 emissions. Here, we present a new model of sediment chemistry that incorporates the latest experimental findings on calcium carbonate dissolution kinetics. This model can be used to predict how marine sediments evolve through time in response to environmental perturbations.
Matthew P. Humphreys, Erik H. Meesters, Henk de Haas, Szabina Karancz, Louise Delaigue, Karel Bakker, Gerard Duineveld, Siham de Goeyse, Andreas F. Haas, Furu Mienis, Sharyn Ossebaar, and Fleur C. van Duyl
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A series of submarine sinkholes were recently discovered on Luymes Bank, part of Saba Bank, a carbonate platform in the Caribbean Netherlands. Here, we investigate the waters inside these sinkholes for the first time. One of the sinkholes contained a body of dense, low-oxygen and low-pH water, which we call the
acid lake. We use measurements of seawater chemistry to work out what processes were responsible for forming the acid lake and discuss the consequences for the carbonate platform.
Matthew P. Humphreys, Ernie R. Lewis, Jonathan D. Sharp, and Denis Pierrot
Geosci. Model Dev., 15, 15–43, https://doi.org/10.5194/gmd-15-15-2022, https://doi.org/10.5194/gmd-15-15-2022, 2022
Short summary
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The ocean helps to mitigate our impact on Earth's climate by absorbing about a quarter of the carbon dioxide (CO2) released by human activities each year. However, once absorbed, chemical reactions between CO2 and water reduce seawater pH (
ocean acidification), which may have adverse effects on marine ecosystems. Our Python package, PyCO2SYS, models the chemical reactions of CO2 in seawater, allowing us to quantify the corresponding changes in pH and related chemical properties.
Luca Possenti, Ingunn Skjelvan, Dariia Atamanchuk, Anders Tengberg, Matthew P. Humphreys, Socratis Loucaides, Liam Fernand, and Jan Kaiser
Ocean Sci., 17, 593–614, https://doi.org/10.5194/os-17-593-2021, https://doi.org/10.5194/os-17-593-2021, 2021
Short summary
Short summary
A Seaglider was deployed for 8 months in the Norwegian Sea mounting an oxygen and, for the first time, a CO2 optode and a chlorophyll fluorescence sensor. The oxygen and CO2 data were used to assess the spatial and temporal variability and calculate the net community production, N(O2) and N(CT). The dataset was used to calculate net community production from inventory changes, air–sea flux, diapycnal mixing and entrainment.
Yasmina Ourradi, Gert-Jan Reichart, Sonja van Leeuwen, and Matthew Humphreys
EGUsphere, https://doi.org/10.5194/egusphere-2025-5050, https://doi.org/10.5194/egusphere-2025-5050, 2025
This preprint is open for discussion and under review for Biogeosciences (BG).
Short summary
Short summary
We measured pH at high frequency for nearly a year at the Wadden Sea-North Sea interface. Biological activity mainly controls daily pH variations, while water exchange affects alkalinity. Dissolved inorganic carbon is influenced by both processes. Our research shows the Wadden Sea releases CO2 to the atmosphere. Understanding these patterns is crucial for predicting how coastal seas respond to changing climate and water conditions.
Ben A. Cala, Mariette Wolthers, Olivier Sulpis, Jonathan D. Sharp, and Matthew P. Humphreys
EGUsphere, https://doi.org/10.5194/egusphere-2025-5059, https://doi.org/10.5194/egusphere-2025-5059, 2025
This preprint is open for discussion and under review for Ocean Science (OS).
Short summary
Short summary
Magnesium calcites are minerals produced by some marine organisms. Understanding how these minerals dissolve helps us to predict how the ocean stores carbon. We developed a new method to calculate the solubility of these minerals in seawater, using existing laboratory data and taking into account the effects of temperature, salinity and pressure. Applying this method globally, we found that magnesium calcites dissolve deeper than previously thought.
Louise Delaigue, Gert-Jan Reichart, Li Qiu, Eric P. Achterberg, Yasmina Ourradi, Chris Galley, André Mutzberg, and Matthew P. Humphreys
Biogeosciences, 22, 5103–5121, https://doi.org/10.5194/bg-22-5103-2025, https://doi.org/10.5194/bg-22-5103-2025, 2025
Short summary
Short summary
Our study analysed pH in ocean surface waters to understand how it fluctuates with changes in temperature, salinity, and biological activities. We found that temperature mainly controls daily pH variations, but biological processes also play a role, especially in affecting CO2 levels between the ocean and atmosphere. Our research shows how these factors together maintain the balance of ocean chemistry, which is crucial for predicting changes in marine environments.
Anne L. Kruijt, Robin van Dijk, Olivier Sulpis, Luc Beaufort, Guillaume Lassus, Geert-Jan Brummer, A. Daniëlle van der Burg, Ben A. Cala, Yasmina Ourradi, Katja T. C. A. Peijnenburg, Matthew P. Humphreys, Sonia Chaabane, Appy Sluijs, and Jack J. Middelburg
EGUsphere, https://doi.org/10.5194/egusphere-2025-4234, https://doi.org/10.5194/egusphere-2025-4234, 2025
Short summary
Short summary
We measured the three main types of plankton that produce calcium carbonate in the ocean, at the same time and location. While coccolithophores were the biggest contributors, we found that planktonic gastropods, not foraminifera, were the second largest contributor. This challenges the current view and improves our understanding of how these organisms influence oceans’ carbon cycling.
Hinne Florian van der Zant, Olivier Sulpis, Jack J. Middelburg, Matthew P. Humphreys, Raphaël Savelli, Dustin Carroll, Dimitris Menemenlis, Kay Sušelj, and Vincent Le Fouest
EGUsphere, https://doi.org/10.5194/egusphere-2025-2244, https://doi.org/10.5194/egusphere-2025-2244, 2025
Short summary
Short summary
We developed a model to simulate seafloor biogeochemical processes across a wide range of marine environments, from shallow coastal zones to deep-sea sediments. From this model, we derived a set of simple equations that predict how carbon, oxygen, and alkalinity are exchanged between sediments and overlying waters. These equations provide an efficient way to improve how ocean models represent seafloor interactions, which are often missing or overly simplified.
Li-Qing Jiang, Amanda Fay, Jens Daniel Müller, Lydia Keppler, Dustin Carroll, Siv K. Lauvset, Tim DeVries, Judith Hauck, Christian Rödenbeck, Luke Gregor, Nicolas Metzl, Andrea J. Fassbender, Jean-Pierre Gattuso, Peter Landschützer, Rik Wanninkhof, Christopher Sabine, Simone R. Alin, Mario Hoppema, Are Olsen, Matthew P. Humphreys, Kumiko Azetsu-Scott, Dorothee C. E. Bakker, Leticia Barbero, Nicholas R. Bates, Nicole Besemer, Henry C. Bittig, Albert E. Boyd, Daniel Broullón, Wei-Jun Cai, Brendan R. Carter, Thi-Tuyet-Trang Chau, Chen-Tung Arthur Chen, Frédéric Cyr, John E. Dore, Ian Enochs, Richard A. Feely, Hernan E. Garcia, Marion Gehlen, Lucas Gloege, Melchor González-Dávila, Nicolas Gruber, Yosuke Iida, Masao Ishii, Esther Kennedy, Alex Kozyr, Nico Lange, Claire Lo Monaco, Derek P. Manzello, Galen A. McKinley, Natalie M. Monacci, Xose A. Padin, Ana M. Palacio-Castro, Fiz F. Pérez, Alizée Roobaert, J. Magdalena Santana-Casiano, Jonathan Sharp, Adrienne Sutton, Jim Swift, Toste Tanhua, Maciej Telszewski, Jens Terhaar, Ruben van Hooidonk, Anton Velo, Andrew J. Watson, Angelicque E. White, Zelun Wu, Hyelim Yoo, and Jiye Zeng
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-255, https://doi.org/10.5194/essd-2025-255, 2025
Preprint under review for ESSD
Short summary
Short summary
This review article provides an overview of 60 existing ocean carbonate chemistry data products, encompassing a broad range of types, including compilations of cruise datasets, gap-filled observational products, model simulations, and more. It is designed to help researchers identify and access the data products that best support their scientific objectives, thereby facilitating progress in understanding the ocean's changing carbonate chemistry.
Matthew P. Humphreys
Ocean Sci., 20, 1325–1350, https://doi.org/10.5194/os-20-1325-2024, https://doi.org/10.5194/os-20-1325-2024, 2024
Short summary
Short summary
The ocean takes up carbon dioxide (CO2) from the atmosphere, slowing climate change. This CO2 uptake is controlled by a property called ƒCO2. Seawater ƒCO2 changes as seawater warms or cools, although by an uncertain amount; measurements and calculations give inconsistent results. Here, we work out how ƒCO2 should, in theory, respond to temperature. This matches field data and model calculations but still has discrepancies with scarce laboratory results, which need more measurements to resolve.
Siv K. Lauvset, Nico Lange, Toste Tanhua, Henry C. Bittig, Are Olsen, Alex Kozyr, Marta Álvarez, Kumiko Azetsu-Scott, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Mario Hoppema, Matthew P. Humphreys, Masao Ishii, Emil Jeansson, Akihiko Murata, Jens Daniel Müller, Fiz F. Pérez, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Adam Ulfsbo, Anton Velo, Ryan J. Woosley, and Robert M. Key
Earth Syst. Sci. Data, 16, 2047–2072, https://doi.org/10.5194/essd-16-2047-2024, https://doi.org/10.5194/essd-16-2047-2024, 2024
Short summary
Short summary
GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv2.2023 is the fifth update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality controlling, including systematic evaluation of measurement biases. This version contains data from 1108 hydrographic cruises covering the world's oceans from 1972 to 2021.
Siv K. Lauvset, Nico Lange, Toste Tanhua, Henry C. Bittig, Are Olsen, Alex Kozyr, Simone Alin, Marta Álvarez, Kumiko Azetsu-Scott, Leticia Barbero, Susan Becker, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Richard A. Feely, Mario Hoppema, Matthew P. Humphreys, Masao Ishii, Emil Jeansson, Li-Qing Jiang, Steve D. Jones, Claire Lo Monaco, Akihiko Murata, Jens Daniel Müller, Fiz F. Pérez, Benjamin Pfeil, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Bronte Tilbrook, Adam Ulfsbo, Anton Velo, Ryan J. Woosley, and Robert M. Key
Earth Syst. Sci. Data, 14, 5543–5572, https://doi.org/10.5194/essd-14-5543-2022, https://doi.org/10.5194/essd-14-5543-2022, 2022
Short summary
Short summary
GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv2.2022 is the fourth update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality controlling, including systematic evaluation of measurement biases. This version contains data from 1085 hydrographic cruises covering the world's oceans from 1972 to 2021.
Elise S. Droste, Mario Hoppema, Melchor González-Dávila, Juana Magdalena Santana-Casiano, Bastien Y. Queste, Giorgio Dall'Olmo, Hugh J. Venables, Gerd Rohardt, Sharyn Ossebaar, Daniel Schuller, Sunke Trace-Kleeberg, and Dorothee C. E. Bakker
Ocean Sci., 18, 1293–1320, https://doi.org/10.5194/os-18-1293-2022, https://doi.org/10.5194/os-18-1293-2022, 2022
Short summary
Short summary
Tides affect the marine carbonate chemistry of a coastal polynya neighbouring the Ekström Ice Shelf by movement of seawater with different physical and biogeochemical properties. The result is that the coastal polynya in the summer can switch between being a sink or a source of CO2 multiple times a day. We encourage consideration of tides when collecting in polar coastal regions to account for tide-driven variability and to avoid overestimations or underestimations of air–sea CO2 exchange.
Olivier Sulpis, Matthew P. Humphreys, Monica M. Wilhelmus, Dustin Carroll, William M. Berelson, Dimitris Menemenlis, Jack J. Middelburg, and Jess F. Adkins
Geosci. Model Dev., 15, 2105–2131, https://doi.org/10.5194/gmd-15-2105-2022, https://doi.org/10.5194/gmd-15-2105-2022, 2022
Short summary
Short summary
A quarter of the surface of the Earth is covered by marine sediments rich in calcium carbonates, and their dissolution acts as a giant antacid tablet protecting the ocean against human-made acidification caused by massive CO2 emissions. Here, we present a new model of sediment chemistry that incorporates the latest experimental findings on calcium carbonate dissolution kinetics. This model can be used to predict how marine sediments evolve through time in response to environmental perturbations.
Matthew P. Humphreys, Erik H. Meesters, Henk de Haas, Szabina Karancz, Louise Delaigue, Karel Bakker, Gerard Duineveld, Siham de Goeyse, Andreas F. Haas, Furu Mienis, Sharyn Ossebaar, and Fleur C. van Duyl
Biogeosciences, 19, 347–358, https://doi.org/10.5194/bg-19-347-2022, https://doi.org/10.5194/bg-19-347-2022, 2022
Short summary
Short summary
A series of submarine sinkholes were recently discovered on Luymes Bank, part of Saba Bank, a carbonate platform in the Caribbean Netherlands. Here, we investigate the waters inside these sinkholes for the first time. One of the sinkholes contained a body of dense, low-oxygen and low-pH water, which we call the
acid lake. We use measurements of seawater chemistry to work out what processes were responsible for forming the acid lake and discuss the consequences for the carbonate platform.
Matthew P. Humphreys, Ernie R. Lewis, Jonathan D. Sharp, and Denis Pierrot
Geosci. Model Dev., 15, 15–43, https://doi.org/10.5194/gmd-15-15-2022, https://doi.org/10.5194/gmd-15-15-2022, 2022
Short summary
Short summary
The ocean helps to mitigate our impact on Earth's climate by absorbing about a quarter of the carbon dioxide (CO2) released by human activities each year. However, once absorbed, chemical reactions between CO2 and water reduce seawater pH (
ocean acidification), which may have adverse effects on marine ecosystems. Our Python package, PyCO2SYS, models the chemical reactions of CO2 in seawater, allowing us to quantify the corresponding changes in pH and related chemical properties.
Luca Possenti, Ingunn Skjelvan, Dariia Atamanchuk, Anders Tengberg, Matthew P. Humphreys, Socratis Loucaides, Liam Fernand, and Jan Kaiser
Ocean Sci., 17, 593–614, https://doi.org/10.5194/os-17-593-2021, https://doi.org/10.5194/os-17-593-2021, 2021
Short summary
Short summary
A Seaglider was deployed for 8 months in the Norwegian Sea mounting an oxygen and, for the first time, a CO2 optode and a chlorophyll fluorescence sensor. The oxygen and CO2 data were used to assess the spatial and temporal variability and calculate the net community production, N(O2) and N(CT). The dataset was used to calculate net community production from inventory changes, air–sea flux, diapycnal mixing and entrainment.
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Short summary
The ocean is one of the main reservoirs of carbon dioxide (CO2) on Earth's surface, so it plays an important role in modulating the climate. In this paper, we propose an update to how dissolved CO2 in seawater is determined from laboratory data, which can sometimes improve the accuracy of these measurements.
The ocean is one of the main reservoirs of carbon dioxide (CO2) on Earth's surface, so it plays...