Articles | Volume 21, issue 4
https://doi.org/10.5194/os-21-1237-2025
© 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-21-1237-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Local versus far-field control on South Pacific Subantarctic mode water variability
Ciara Pimm
CORRESPONDING AUTHOR
Department of Earth, Ocean and Ecological Sciences, School of Environmental Sciences, University of Liverpool, Liverpool, UK
Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Andrew J. S. Meijers
British Antarctic Survey, NERC, UKRI, Cambridge, UK
Dani C. Jones
British Antarctic Survey, NERC, UKRI, Cambridge, UK
Cooperative Institute for Great Lakes Research (CIGLR), University of Michigan, Ann Arbor, MI, USA
Richard G. Williams
Department of Earth, Ocean and Ecological Sciences, School of Environmental Sciences, University of Liverpool, Liverpool, UK
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EGUsphere, https://doi.org/10.5194/egusphere-2025-2423, https://doi.org/10.5194/egusphere-2025-2423, 2025
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Neill Mackay, Taimoor Sohail, Jan David Zika, Richard G. Williams, Oliver Andrews, and Andrew James Watson
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The ocean absorbs carbon dioxide from the atmosphere, mitigating climate change, but estimates of the uptake do not always agree. There is a need to reconcile these differing estimates and to improve our understanding of ocean carbon uptake. We present a new method for estimating ocean carbon uptake and test it with model data. The method effectively diagnoses the ocean carbon uptake from limited data and therefore shows promise for reconciling different observational estimates.
Philip Goodwin, Richard Williams, Paulo Ceppi, and B. B. Cael
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Climate feedbacks are normally evaluated by considering the change over time for Earth's energy balance and surface temperatures in the climate system. However, we only have around 1 degree Celsius of temperature change to utilise. Here, climate feedbacks are instead evaluated from the change in latitude of Earth's energy balance and surface temperatures, where we have around 70 degrees Celsius of temperature change to utilise.
Dani C. Jones, Maike Sonnewald, Shenjie Zhou, Ute Hausmann, Andrew J. S. Meijers, Isabella Rosso, Lars Boehme, Michael P. Meredith, and Alberto C. Naveira Garabato
Ocean Sci., 19, 857–885, https://doi.org/10.5194/os-19-857-2023, https://doi.org/10.5194/os-19-857-2023, 2023
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Machine learning is transforming oceanography. For example, unsupervised classification approaches help researchers identify underappreciated structures in ocean data, helping to generate new hypotheses. In this work, we use a type of unsupervised classification to identify structures in the temperature and salinity structure of the Weddell Gyre, which is an important region for global ocean circulation and for climate. We use our method to generate new ideas about mixing in the Weddell Gyre.
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We present a new method for reconstructing ocean carbon using climate models and temperature and salinity observations. To test this method, we reconstruct modelled carbon using synthetic observations consistent with current sampling programmes. Sensitivity tests show skill in reconstructing carbon trends and variability within the upper 2000 m. Our results indicate that this method can be used for a new global estimate for ocean carbon content.
Negar Vakilifard, Richard G. Williams, Philip B. Holden, Katherine Turner, Neil R. Edwards, and David J. Beerling
Biogeosciences, 19, 4249–4265, https://doi.org/10.5194/bg-19-4249-2022, https://doi.org/10.5194/bg-19-4249-2022, 2022
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To remain within the Paris climate agreement, there is an increasing need to develop and implement carbon capture and sequestration techniques. The global climate benefits of implementing negative emission technologies over the next century are assessed using an Earth system model covering a wide range of plausible climate states. In some model realisations, there is continued warming after emissions cease. This continued warming is avoided if negative emissions are incorporated.
Anna Katavouta and Richard G. Williams
Biogeosciences, 18, 3189–3218, https://doi.org/10.5194/bg-18-3189-2021, https://doi.org/10.5194/bg-18-3189-2021, 2021
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Diagnostics of the latest-generation Earth system models reveal the ocean will continue to absorb a large fraction of the anthropogenic carbon released to the atmosphere in the next century, with the Atlantic Ocean storing a large amount of this carbon relative to its size. The ability of the ocean to absorb carbon will reduce in the future as the ocean warms and acidifies. This reduction is larger in the Atlantic Ocean due to a weakening of the meridional overturning with changes in climate.
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Co-editor-in-chief
This paper highlights a new implementation of density co-ordinate functionality within an adjoint ocean model, the MITgcm ECCO adjoint. This is illustrated accordingly with a science application investigating the variability of Subantarctic Mode Water. The use of adjoints helps to trace causal links within the ocean, and the density-following feature is of particular interest for the ocean community with many possible further applications.
This paper highlights a new implementation of density co-ordinate functionality within an...
Short summary
Subantarctic mode water in the South Pacific Ocean is important due to its role in the uptake and transport of anthropogenic heat and carbon. The Subantarctic mode water region can be split into two pools using mixed-layer-depth properties. Sensitivity experiments are used to understand the effects of heating and wind on each pool. It is found that the optimal conditions to form large amounts of Subantarctic mode water in the South Pacific are local cooling and upstream warming combined.
Subantarctic mode water in the South Pacific Ocean is important due to its role in the uptake...