Articles | Volume 15, issue 17
https://doi.org/10.5194/gmd-15-6541-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-15-6541-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Model experiment description paper
| 
31 Aug 2022
Model experiment description paper |
| 31 Aug 2022
| 31 Aug 2022
Observing system simulation experiments reveal that subsurface temperature observations improve estimates of circulation and heat content in a dynamic western boundary current
Coastal and Regional Oceanography Lab, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, NSW, Australia
Colette Kerry
Coastal and Regional Oceanography Lab, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, NSW, Australia
Moninya Roughan
Coastal and Regional Oceanography Lab, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, NSW, Australia
Shane R. Keating
School of Mathematics and Statistics, UNSW Sydney, Sydney, NSW, Australia
Related authors
Johanna Beckmann, Ronja Reese, Felicity S. McCormack, Sue Cook, Lawrence Bird, Dawid Gwyther, Daniel Richards, Matthias Scheiter, Yu Wang, Hélène Seroussi, Ayako Abe‐Ouchi, Torsten Albrecht, Jorge Alvarez‐Solas, Xylar S. Asay‐Davis, Jean‐Baptiste Barre, Constantijn J. Berends, Jorge Bernales, Javier Blasco, Justine Caillet, David M. Chandler, Violaine Coulon, Richard Cullather, Christophe Dumas, Benjamin K. Galton‐Fenzi, Julius Garbe, Fabien Gillet‐Chaulet, Rupert Gladstone, Heiko Goelzer, Nicholas R. Golledge, Ralf Greve, G. Hilmar Gudmundsson, Holly Kyeore Han, Trevor R. Hillebrand, Matthew J. Hoffman, Philippe Huybrechts, Nicolas C. Jourdain, Ann Kristin Klose, Petra M. Langebroek, Gunter R. Leguy, William H. Lipscomb, Daniel P. Lowry, Pierre Mathiot, Marisa Montoya, Mathieu Morlighem, Sophie Nowicki, Frank Pattyn, Antony J. Payne, Tyler Pelle, Aurélien Quiquet, Alexander Robinson, Leopekka Saraste, Erika G. Simon, Sainan Sun, Jake P. Twarog, Luke D. Trusel, Benoit Urruty, Jonas Van Breedam, Roderik S. W. van de Wal, Chen Zhao, and Thomas Zwinger
EGUsphere, https://doi.org/10.5194/egusphere-2025-4069, https://doi.org/10.5194/egusphere-2025-4069, 2025
This preprint is open for discussion and under review for The Cryosphere (TC).
Short summary
Short summary
Antarctica holds enough ice to raise sea levels by many meters, but its future is uncertain. Warm ocean water melts ice shelves from below, letting inland ice flow faster into the sea. By 2300, Antarctica could add 0.6–4.4 m to sea levels. Our study identifies two key factors—how strongly shelves melt and how the ice responds. These explain much of the range, and refining them in models may improve future predictions.
Lawrence A. Bird, Vitaliy Ogarko, Laurent Ailleres, Lachlan Grose, Jérémie Giraud, Felicity S. McCormack, David E. Gwyther, Jason L. Roberts, Richard S. Jones, and Andrew N. Mackintosh
The Cryosphere, 19, 3355–3380, https://doi.org/10.5194/tc-19-3355-2025, https://doi.org/10.5194/tc-19-3355-2025, 2025
Short summary
Short summary
The terrain of the seafloor has important controls on the access of warm water below floating ice shelves around Antarctica. Here, we present an open-source method to infer what the seafloor looks like around the Antarctic continent and within these ice shelf cavities, using measurements of the Earth's gravitational field. We present an improved seafloor map for the Vincennes Bay region in East Antarctica and assess its impact on ice melt rates.
Claire K. Yung, Xylar S. Asay-Davis, Alistair Adcroft, Christopher Y. S. Bull, Jan De Rydt, Michael S. Dinniman, Benjamin K. Galton-Fenzi, Daniel Goldberg, David E. Gwyther, Robert Hallberg, Matthew Harrison, Tore Hattermann, David M. Holland, Denise Holland, Paul R. Holland, James R. Jordan, Nicolas C. Jourdain, Kazuya Kusahara, Gustavo Marques, Pierre Mathiot, Dimitris Menemenlis, Adele K. Morrison, Yoshihiro Nakayama, Olga Sergienko, Robin S. Smith, Alon Stern, Ralph Timmermann, and Qin Zhou
EGUsphere, https://doi.org/10.5194/egusphere-2025-1942, https://doi.org/10.5194/egusphere-2025-1942, 2025
Short summary
Short summary
ISOMIP+ compares 12 ocean models that simulate ice-ocean interactions in a common, idealised, static ice shelf cavity setup, aiming to assess and understand inter-model variability. Models simulate similar basal melt rate patterns, ocean profiles and circulation but differ in ice-ocean boundary layer properties and spatial distributions of melting. Ice-ocean boundary layer representation is a key area for future work, as are realistic-domain ice sheet-ocean model intercomparisons.
Benjamin Keith Galton-Fenzi, Richard Porter-Smith, Sue Cook, Eva Cougnon, David E. Gwyther, Wilma G. C. Huneke, Madelaine G. Rosevear, Xylar Asay-Davis, Fabio Boeira Dias, Michael S. Dinniman, David Holland, Kazuya Kusahara, Kaitlin A. Naughten, Keith W. Nicholls, Charles Pelletier, Ole Richter, Helene L. Seroussi, and Ralph Timmermann
EGUsphere, https://doi.org/10.5194/egusphere-2024-4047, https://doi.org/10.5194/egusphere-2024-4047, 2025
Short summary
Short summary
Melting beneath Antarctica’s floating ice shelves is key to future sea-level rise. We compare several different ocean simulations with satellite measurements, and provide the first multi-model average estimate of melting and refreezing driven by both ocean temperature and currents beneath ice shelves. The multi-model average can provide a useful tool for better understanding the role of ice shelf melting in present-day and future ice-sheet changes and informing coastal adaptation efforts.
Qin Zhou, Chen Zhao, Rupert Gladstone, Tore Hattermann, David Gwyther, and Benjamin Galton-Fenzi
Geosci. Model Dev., 17, 8243–8265, https://doi.org/10.5194/gmd-17-8243-2024, https://doi.org/10.5194/gmd-17-8243-2024, 2024
Short summary
Short summary
We introduce an accelerated forcing approach to address timescale discrepancies between the ice sheets and ocean components in coupled modelling by reducing the ocean simulation duration. The approach is evaluated using idealized coupled models, and its limitations in real-world applications are discussed. Our results suggest it can be a valuable tool for process-oriented coupled ice sheet–ocean modelling and downscaling climate simulations with such models.
Colette Gabrielle Kerry, Moninya Roughan, Shane Keating, David Gwyther, Gary Brassington, Adil Siripatana, and Joao Marcos A. C. Souza
Geosci. Model Dev., 17, 2359–2386, https://doi.org/10.5194/gmd-17-2359-2024, https://doi.org/10.5194/gmd-17-2359-2024, 2024
Short summary
Short summary
Ocean forecasting relies on the combination of numerical models and ocean observations through data assimilation (DA). Here we assess the performance of two DA systems in a dynamic western boundary current, the East Australian Current, across a common modelling and observational framework. We show that the more advanced, time-dependent method outperforms the time-independent method for forecast horizons of 5 d. This advocates the use of advanced methods for highly variable oceanic regions.
David E. Gwyther, Shane R. Keating, Colette Kerry, and Moninya Roughan
Geosci. Model Dev., 16, 157–178, https://doi.org/10.5194/gmd-16-157-2023, https://doi.org/10.5194/gmd-16-157-2023, 2023
Short summary
Short summary
Ocean eddies are important for weather, climate, biology, navigation, and search and rescue. Since eddies change rapidly, models that incorporate or assimilate observations are required to produce accurate eddy timings and locations, yet the model accuracy is rarely assessed below the surface. We use a unique type of ocean model experiment to assess three-dimensional eddy structure in the East Australian Current and explore two pathways in which this subsurface structure is being degraded.
Chen Zhao, Rupert Gladstone, Benjamin Keith Galton-Fenzi, David Gwyther, and Tore Hattermann
Geosci. Model Dev., 15, 5421–5439, https://doi.org/10.5194/gmd-15-5421-2022, https://doi.org/10.5194/gmd-15-5421-2022, 2022
Short summary
Short summary
We use a coupled ice–ocean model to explore an oscillation feature found in several contributing models to MISOMIP1. The oscillation is closely related to the discretized grounding line retreat and likely strengthened by the buoyancy–melt feedback and/or melt–geometry feedback near the grounding line, and frequent ice–ocean coupling. Our model choices have a non-trivial impact on mean melt and ocean circulation strength, which might be interesting for the coupled ice–ocean community.
Ole Richter, David E. Gwyther, Matt A. King, and Benjamin K. Galton-Fenzi
The Cryosphere, 16, 1409–1429, https://doi.org/10.5194/tc-16-1409-2022, https://doi.org/10.5194/tc-16-1409-2022, 2022
Short summary
Short summary
Tidal currents may play an important role in Antarctic ice sheet retreat by changing the rate at which the ocean melts glaciers. Here, using a computational ocean model, we derive the first estimate of present-day tidal melting that covers all of Antarctica. Our results suggest that large-scale ocean models aiming to accurately predict ice melt rates will need to account for the effects of tides. The inclusion of tide-induced friction at the ice–ocean interface should be prioritized.
Ole Richter, David E. Gwyther, Benjamin K. Galton-Fenzi, and Kaitlin A. Naughten
Geosci. Model Dev., 15, 617–647, https://doi.org/10.5194/gmd-15-617-2022, https://doi.org/10.5194/gmd-15-617-2022, 2022
Short summary
Short summary
Here we present an improved model of the Antarctic continental shelf ocean and demonstrate that it is capable of reproducing present-day conditions. The improvements are fundamental and regard the inclusion of tides and ocean eddies. We conclude that the model is well suited to gain new insights into processes that are important for Antarctic ice sheet retreat and global ocean changes. Hence, the model will ultimately help to improve projections of sea level rise and climate change.
Johanna Beckmann, Ronja Reese, Felicity S. McCormack, Sue Cook, Lawrence Bird, Dawid Gwyther, Daniel Richards, Matthias Scheiter, Yu Wang, Hélène Seroussi, Ayako Abe‐Ouchi, Torsten Albrecht, Jorge Alvarez‐Solas, Xylar S. Asay‐Davis, Jean‐Baptiste Barre, Constantijn J. Berends, Jorge Bernales, Javier Blasco, Justine Caillet, David M. Chandler, Violaine Coulon, Richard Cullather, Christophe Dumas, Benjamin K. Galton‐Fenzi, Julius Garbe, Fabien Gillet‐Chaulet, Rupert Gladstone, Heiko Goelzer, Nicholas R. Golledge, Ralf Greve, G. Hilmar Gudmundsson, Holly Kyeore Han, Trevor R. Hillebrand, Matthew J. Hoffman, Philippe Huybrechts, Nicolas C. Jourdain, Ann Kristin Klose, Petra M. Langebroek, Gunter R. Leguy, William H. Lipscomb, Daniel P. Lowry, Pierre Mathiot, Marisa Montoya, Mathieu Morlighem, Sophie Nowicki, Frank Pattyn, Antony J. Payne, Tyler Pelle, Aurélien Quiquet, Alexander Robinson, Leopekka Saraste, Erika G. Simon, Sainan Sun, Jake P. Twarog, Luke D. Trusel, Benoit Urruty, Jonas Van Breedam, Roderik S. W. van de Wal, Chen Zhao, and Thomas Zwinger
EGUsphere, https://doi.org/10.5194/egusphere-2025-4069, https://doi.org/10.5194/egusphere-2025-4069, 2025
This preprint is open for discussion and under review for The Cryosphere (TC).
Short summary
Short summary
Antarctica holds enough ice to raise sea levels by many meters, but its future is uncertain. Warm ocean water melts ice shelves from below, letting inland ice flow faster into the sea. By 2300, Antarctica could add 0.6–4.4 m to sea levels. Our study identifies two key factors—how strongly shelves melt and how the ice responds. These explain much of the range, and refining them in models may improve future predictions.
Lawrence A. Bird, Vitaliy Ogarko, Laurent Ailleres, Lachlan Grose, Jérémie Giraud, Felicity S. McCormack, David E. Gwyther, Jason L. Roberts, Richard S. Jones, and Andrew N. Mackintosh
The Cryosphere, 19, 3355–3380, https://doi.org/10.5194/tc-19-3355-2025, https://doi.org/10.5194/tc-19-3355-2025, 2025
Short summary
Short summary
The terrain of the seafloor has important controls on the access of warm water below floating ice shelves around Antarctica. Here, we present an open-source method to infer what the seafloor looks like around the Antarctic continent and within these ice shelf cavities, using measurements of the Earth's gravitational field. We present an improved seafloor map for the Vincennes Bay region in East Antarctica and assess its impact on ice melt rates.
Claire K. Yung, Xylar S. Asay-Davis, Alistair Adcroft, Christopher Y. S. Bull, Jan De Rydt, Michael S. Dinniman, Benjamin K. Galton-Fenzi, Daniel Goldberg, David E. Gwyther, Robert Hallberg, Matthew Harrison, Tore Hattermann, David M. Holland, Denise Holland, Paul R. Holland, James R. Jordan, Nicolas C. Jourdain, Kazuya Kusahara, Gustavo Marques, Pierre Mathiot, Dimitris Menemenlis, Adele K. Morrison, Yoshihiro Nakayama, Olga Sergienko, Robin S. Smith, Alon Stern, Ralph Timmermann, and Qin Zhou
EGUsphere, https://doi.org/10.5194/egusphere-2025-1942, https://doi.org/10.5194/egusphere-2025-1942, 2025
Short summary
Short summary
ISOMIP+ compares 12 ocean models that simulate ice-ocean interactions in a common, idealised, static ice shelf cavity setup, aiming to assess and understand inter-model variability. Models simulate similar basal melt rate patterns, ocean profiles and circulation but differ in ice-ocean boundary layer properties and spatial distributions of melting. Ice-ocean boundary layer representation is a key area for future work, as are realistic-domain ice sheet-ocean model intercomparisons.
Manh Cuong Tran, Moninya Roughan, and Amandine Schaeffer
Earth Syst. Sci. Data, 17, 937–963, https://doi.org/10.5194/essd-17-937-2025, https://doi.org/10.5194/essd-17-937-2025, 2025
Short summary
Short summary
The East Australian Current (EAC) plays an important role in the marine ecosystem and climate of the region. To understand the EAC regime and the inner shelf dynamics, we implement a variational approach to produce the first multiyear coastal radar dataset (2012–2023) in this region. The validated data allow for a comprehensive investigation of the EAC dynamics. This dataset will be useful for understanding the complex EAC regime and its far-reaching impacts on the shelf environment.
Benjamin Keith Galton-Fenzi, Richard Porter-Smith, Sue Cook, Eva Cougnon, David E. Gwyther, Wilma G. C. Huneke, Madelaine G. Rosevear, Xylar Asay-Davis, Fabio Boeira Dias, Michael S. Dinniman, David Holland, Kazuya Kusahara, Kaitlin A. Naughten, Keith W. Nicholls, Charles Pelletier, Ole Richter, Helene L. Seroussi, and Ralph Timmermann
EGUsphere, https://doi.org/10.5194/egusphere-2024-4047, https://doi.org/10.5194/egusphere-2024-4047, 2025
Short summary
Short summary
Melting beneath Antarctica’s floating ice shelves is key to future sea-level rise. We compare several different ocean simulations with satellite measurements, and provide the first multi-model average estimate of melting and refreezing driven by both ocean temperature and currents beneath ice shelves. The multi-model average can provide a useful tool for better understanding the role of ice shelf melting in present-day and future ice-sheet changes and informing coastal adaptation efforts.
Qin Zhou, Chen Zhao, Rupert Gladstone, Tore Hattermann, David Gwyther, and Benjamin Galton-Fenzi
Geosci. Model Dev., 17, 8243–8265, https://doi.org/10.5194/gmd-17-8243-2024, https://doi.org/10.5194/gmd-17-8243-2024, 2024
Short summary
Short summary
We introduce an accelerated forcing approach to address timescale discrepancies between the ice sheets and ocean components in coupled modelling by reducing the ocean simulation duration. The approach is evaluated using idealized coupled models, and its limitations in real-world applications are discussed. Our results suggest it can be a valuable tool for process-oriented coupled ice sheet–ocean modelling and downscaling climate simulations with such models.
Colette Gabrielle Kerry, Moninya Roughan, Shane Keating, David Gwyther, Gary Brassington, Adil Siripatana, and Joao Marcos A. C. Souza
Geosci. Model Dev., 17, 2359–2386, https://doi.org/10.5194/gmd-17-2359-2024, https://doi.org/10.5194/gmd-17-2359-2024, 2024
Short summary
Short summary
Ocean forecasting relies on the combination of numerical models and ocean observations through data assimilation (DA). Here we assess the performance of two DA systems in a dynamic western boundary current, the East Australian Current, across a common modelling and observational framework. We show that the more advanced, time-dependent method outperforms the time-independent method for forecast horizons of 5 d. This advocates the use of advanced methods for highly variable oceanic regions.
Michael Hemming, Moninya Roughan, and Amandine Schaeffer
Earth Syst. Sci. Data, 16, 887–901, https://doi.org/10.5194/essd-16-887-2024, https://doi.org/10.5194/essd-16-887-2024, 2024
Short summary
Short summary
We present new datasets that are useful for exploring extreme ocean temperature events in Australian coastal waters. These datasets span multiple decades, starting from the 1940s and 1950s, and include observations from the surface to the bottom at four coastal sites. The datasets provide valuable insights into the intensity, frequency and timing of extreme warm and cold temperature events and include event characteristics such as duration, onset and decline rates and their categorisation.
Michael P. Hemming, Moninya Roughan, Neil Malan, and Amandine Schaeffer
Ocean Sci., 19, 1145–1162, https://doi.org/10.5194/os-19-1145-2023, https://doi.org/10.5194/os-19-1145-2023, 2023
Short summary
Short summary
We estimate subsurface linear and non-linear temperature trends at five coastal sites adjacent to the East Australian Current (EAC). We see accelerating trends at both 34.1 and 42.6 °S and place our results in the context of previously reported trends, highlighting that magnitudes are depth-dependent and vary across latitude. Our results indicate the important role of regional dynamics and show the necessity of subsurface data for the improved understanding of regional climate change impacts.
Joao Marcos Azevedo Correia de Souza, Sutara H. Suanda, Phellipe P. Couto, Robert O. Smith, Colette Kerry, and Moninya Roughan
Geosci. Model Dev., 16, 211–231, https://doi.org/10.5194/gmd-16-211-2023, https://doi.org/10.5194/gmd-16-211-2023, 2023
Short summary
Short summary
The current paper describes the configuration and evaluation of the Moana Ocean Hindcast, a > 25-year simulation of the ocean state around New Zealand using the Regional Ocean Modeling System v3.9. This is the first open-access, long-term, continuous, realistic ocean simulation for this region and provides information for improving the understanding of the ocean processes that affect the New Zealand exclusive economic zone.
David E. Gwyther, Shane R. Keating, Colette Kerry, and Moninya Roughan
Geosci. Model Dev., 16, 157–178, https://doi.org/10.5194/gmd-16-157-2023, https://doi.org/10.5194/gmd-16-157-2023, 2023
Short summary
Short summary
Ocean eddies are important for weather, climate, biology, navigation, and search and rescue. Since eddies change rapidly, models that incorporate or assimilate observations are required to produce accurate eddy timings and locations, yet the model accuracy is rarely assessed below the surface. We use a unique type of ocean model experiment to assess three-dimensional eddy structure in the East Australian Current and explore two pathways in which this subsurface structure is being degraded.
Chen Zhao, Rupert Gladstone, Benjamin Keith Galton-Fenzi, David Gwyther, and Tore Hattermann
Geosci. Model Dev., 15, 5421–5439, https://doi.org/10.5194/gmd-15-5421-2022, https://doi.org/10.5194/gmd-15-5421-2022, 2022
Short summary
Short summary
We use a coupled ice–ocean model to explore an oscillation feature found in several contributing models to MISOMIP1. The oscillation is closely related to the discretized grounding line retreat and likely strengthened by the buoyancy–melt feedback and/or melt–geometry feedback near the grounding line, and frequent ice–ocean coupling. Our model choices have a non-trivial impact on mean melt and ocean circulation strength, which might be interesting for the coupled ice–ocean community.
Ole Richter, David E. Gwyther, Matt A. King, and Benjamin K. Galton-Fenzi
The Cryosphere, 16, 1409–1429, https://doi.org/10.5194/tc-16-1409-2022, https://doi.org/10.5194/tc-16-1409-2022, 2022
Short summary
Short summary
Tidal currents may play an important role in Antarctic ice sheet retreat by changing the rate at which the ocean melts glaciers. Here, using a computational ocean model, we derive the first estimate of present-day tidal melting that covers all of Antarctica. Our results suggest that large-scale ocean models aiming to accurately predict ice melt rates will need to account for the effects of tides. The inclusion of tide-induced friction at the ice–ocean interface should be prioritized.
Ole Richter, David E. Gwyther, Benjamin K. Galton-Fenzi, and Kaitlin A. Naughten
Geosci. Model Dev., 15, 617–647, https://doi.org/10.5194/gmd-15-617-2022, https://doi.org/10.5194/gmd-15-617-2022, 2022
Short summary
Short summary
Here we present an improved model of the Antarctic continental shelf ocean and demonstrate that it is capable of reproducing present-day conditions. The improvements are fundamental and regard the inclusion of tides and ocean eddies. We conclude that the model is well suited to gain new insights into processes that are important for Antarctic ice sheet retreat and global ocean changes. Hence, the model will ultimately help to improve projections of sea level rise and climate change.
Cited articles
Ballabrera-Poy, J., Hackert, E., Murtugudde, R., and Busalacchi, A. J.:
An Observing System Simulation Experiment for an Optimal Moored Instrument Array in the Tropical Indian Ocean, J. Climate, 20, 3284–3299, https://doi.org/10.1175/jcli4149.1, 2007. a
Behrens, E., Fernandez, D., and Sutton, P.:
Meridional Oceanic Heat Transport Influences Marine Heatwaves in the Tasman Sea on Interannual to Decadal Timescales, Frontiers in Marine Science, 6, https://doi.org/10.3389/fmars.2019.00228, 2019. a
Brink, K.:
Cross-Shelf Exchange, Annu. Rev. Mar. Sci., 8, 59–78, https://doi.org/10.1146/annurev-marine-010814-015717, 2016. a
Cetina-Heredia, P., Roughan, M., van Sebille, E., and Coleman, M. A.:
Long-term trends in the East Australian Current separation latitude and eddy driven transport, J. Geophys. Res.-Oceans, 119, 4351–4366, https://doi.org/10.1002/2014jc010071, 2014. a, b, c, d
Chamberlain, M. A., Oke, P. R., Fiedler, R. A. S., Beggs, H. M., Brassington, G. B., and Divakaran, P.:
Next generation of Bluelink ocean reanalysis with multiscale data assimilation: BRAN2020, Earth Syst. Sci. Data, 13, 5663–5688, https://doi.org/10.5194/essd-13-5663-2021, 2021. a
Copernicus Marine Service (CMEMS): Global ocean along-track L3 sea surface heights reprocessed (1993-ongoing) tailored for data assimilation (SEALEVEL_GLO_PHY_L3_MY_008_062), Copernicus Marine Service (CMEMS) [data set], https://doi.org/10.48670/moi-00146, 2022. a, b
Elzahaby, Y. and Schaeffer, A.:
Observational Insight Into the Subsurface Anomalies of Marine Heatwaves, Frontiers in Marine Science, 6, https://doi.org/10.3389/fmars.2019.00745, 2019. a
Elzahaby, Y., Schaeffer, A., Roughan, M., and Delaux, S.:
Oceanic Circulation Drives the Deepest and Longest Marine Heatwaves in the East Australian Current System, Geophys. Res. Lett., 48, e2021GL094785, https://doi.org/10.1029/2021gl094785, 2021. a
Fairall, C. W., Bradley, E. F., Rogers, D. P., Edson, J. B., and Young, G. S.:
Bulk parameterization of air–sea fluxes for Tropical Ocean–Global Atmosphere Coupled–Ocean Atmosphere Response Experiment, J. Geophys. Res.-Oceans, 101, 3747–3764, https://doi.org/10.1029/95jc03205, 1996. a
Gasparin, F., Guinehut, S., Mao, C., Mirouze, I., Rémy, E., King, R. R., Hamon, M., Reid, R., Storto, A., Traon, P.-Y. L., Martin, M. J., and Masina, S.:
Requirements for an Integrated in situ Atlantic Ocean Observing System From Coordinated Observing System Simulation Experiments, Frontiers in Marine Science, 6, https://doi.org/10.3389/fmars.2019.00083, 2019. a
Gwyther, D. E., Kerry, C., Roughan, M., and Keating, S.: A high-resolution, 1-year, suite of 4D-Var Observing System Simulation Experiments of the East Australian Current System using the Regional Ocean Modeling System (1.0), Zenodo [code and data set], https://doi.org/10.5281/zenodo.6804480, 2022a. a
Gwyther, D. E., Kerry, C., Roughan, M., and Keating, S.: A high-resolution, 1-year, suite of 4D-Var Observing System Simulation Experiments of the East Australian Current System using the Regional Ocean Modeling System, UNSW Sydney [code and data set], https://doi.org/10.26190/unsworks/24146, 2022b. a
Halliwell, G. R., Srinivasan, A., Kourafalou, V., Yang, H., Willey, D., Hénaff, M. L., and Atlas, R.:
Rigorous Evaluation of a Fraternal Twin Ocean OSSE System for the Open Gulf of Mexico, J. Atmos. Ocean. Tech., 31, 105–130, https://doi.org/10.1175/jtech-d-13-00011.1, 2014. a, b
Halliwell, G. R., Kourafalou, V., Hénaff, M. L., Shay, L. K., and Atlas, R.:
OSSE impact analysis of airborne ocean surveys for improving upper-ocean dynamical and thermodynamical forecasts in the Gulf of Mexico, Prog. Oceanogr., 130, 32–46, https://doi.org/10.1016/j.pocean.2014.09.004, 2015. a, b
Halliwell, G. R., Mehari, M. F., Hénaff, M. L., Kourafalou, V. H., Androulidakis, I. S., Kang, H. S., and Atlas, R.:
North Atlantic Ocean OSSE system: Evaluation of operational ocean observing system components and supplemental seasonal observations for potentially improving tropical cyclone prediction in coupled systems, J. Oper. Oceanogr., 10, 154–175, https://doi.org/10.1080/1755876x.2017.1322770, 2017. a
He, Z., Yang, D., Wang, Y., and Yin, B.:
Impact of 4D-Var data assimilation on modelling of the East China Sea dynamics, Ocean Modell., 176, 102044, https://doi.org/10.1016/j.ocemod.2022.102044, 2022. a
Hu, D., Wu, L., Cai, W., Gupta, A. S., Ganachaud, A., Qiu, B., Gordon, A. L., Lin, X., Chen, Z., Hu, S., Wang, G., Wang, Q., Sprintall, J., Qu, T., Kashino, Y., Wang, F., and Kessler, W. S.:
Pacific western boundary currents and their roles in climate, Nature, 522, 299–308, https://doi.org/10.1038/nature14504, 2015. a
Kamenkovich, I., Haza, A., Gray, A. R., Dufour, C. O., and Garraffo, Z.:
Observing System Simulation Experiments for an array of autonomous biogeochemical profiling floats in the Southern Ocean, J. Geophys. Res.-Oceans, 122, 7595–7611, https://doi.org/10.1002/2017jc012819, 2017. a
Kawabe, M.:
Variations of Current Path, Velocity, and Volume Transport of the Kuroshio in Relation with the Large Meander, J, Phys. Oceanogr., 25, 3103–3117, https://doi.org/10.1175/1520-0485(1995)025<3103:vocpva>2.0.co;2, 1995. a
Kerry, C. and Roughan, M.:
Downstream Evolution of the East Australian Current System: Mean Flow, Seasonal, and Intra-annual Variability, J. Geophys. Res.-Oceans, 125, e2019JC015227, https://doi.org/10.1029/2019jc015227, 2020. a, b, c
Kerry, C., Powell, B., Roughan, M., and Oke, P.:
Development and evaluation of a high-resolution reanalysis of the East Australian Current region using the Regional Ocean Modelling System (ROMS 3.4) and Incremental Strong-Constraint 4-Dimensional Variational (IS4D-Var) data assimilation, Geosci. Model Dev., 9, 3779–3801, https://doi.org/10.5194/gmd-9-3779-2016, 2016. a, b, c, d, e, f, g, h
Kerry, C., Roughan, M., and Powell, B.:
Predicting the submesoscale circulation inshore of the East Australian Current, J. Marine Syst., 204, 103286, https://doi.org/10.1016/j.jmarsys.2019.103286, 2020a. a
Kerry, C., Roughan, M., Powell, B., and Oke, P: A high-resolution reanalysis of the East Australian Current System assimilating an unprecedented observational data set using 4D-Var data assimilation over a two-year period (2012–2013). Version 2017, UNSW Sydney [code and data set], https://doi.org/10.26190/5ebe1f389dd87, 2020b. a
Lee, J.-H., Chang, Y.-S., and Zhang, S.:
Assessment of the JMA Serial Observation Lines in the Northwestern Pacific in OSSE Studies with the GFDL Ensemble Coupled Data Assimilation System, J. Geophys. Res.-Oceans, 125, e2019JC015686, https://doi.org/10.1029/2019jc015686, 2020. a, b
Levin, J., Arango, H. G., Laughlin, B., Wilkin, J., and Moore, A. M.:
The impact of remote sensing observations on cross-shelf transport estimates from 4D-Var analyses of the Mid-Atlantic Bight, Adv. Space Res., 68, 553–570, https://doi.org/10.1016/j.asr.2019.09.012, 2021. a, b
Li, B., de Queiroz, A. R., DeCarolis, J. F., Bane, J., He, R., Keeler, A. G., and Neary, V. S.:
The economics of electricity generation from Gulf Stream currents, Energy, 134, 649–658, https://doi.org/10.1016/j.energy.2017.06.048, 2017. a
Li, J., Kerry, C., and Roughan, M.: A high-resolution, 22-year, free-running, hydrodynamic simulation of the East Australia Current System using the Regional Ocean Modeling System (Version 2.0), UNSW Sydney [code and data set], https://doi.org/10.26190/TT1Q-NP46, 2021b. a
Li, J., Roughan, M., Kerry, C., and Rao, S.:
Impact of Mesoscale Circulation on the Structure of River Plumes During Large Rainfall Events Inshore of the East Australian Current, Frontiers in Marine Science, 9, https://doi.org/10.3389/fmars.2022.815348, 2022b. a
Malan, N., Roughan, M., and Kerry, C.:
The Rate of Coastal Temperature Rise Adjacent to a Warming Western Boundary Current is Nonuniform with Latitude, Geophys. Res. Lett., 48, e2020GL090751, https://doi.org/10.1029/2020gl090751, 2021. a, b
Melet, A., Verron, J., and Brankart, J.-M.:
Potential outcomes of glider data assimilation in the Solomon Sea: Control of the water mass properties and parameter estimation, J. Marine Syst., 94, 232–246, https://doi.org/10.1016/j.jmarsys.2011.12.003, 2012. a, b
Moore, A. M., Arango, H. G., Broquet, G., Edwards, C., Veneziani, M., Powell, B., Foley, D., Doyle, J. D., Costa, D., and Robinson, P.:
The Regional Ocean Modeling System (ROMS) 4-dimensional variational data assimilation systems: Part III – Observation impact and observation sensitivity in the California Current System, Prog. Oceanogr., 91, 74–94, https://doi.org/10.1016/j.pocean.2011.05.005, 2011a. a
Moore, A. M., Arango, H. G., Broquet, G., Powell, B. S., Weaver, A. T., and Zavala-Garay, J.:
The Regional Ocean Modeling System (ROMS) 4-dimensional variational data assimilation systems: Part I – System overview and formulation, Prog. Oceanogr., 91, 34–49, https://doi.org/10.1016/j.pocean.2011.05.004, 2011b. a
Moore, A. M., Edwards, C. A., Fiechter, J., Drake, P., Neveu, E., Arango, H. G., Gürol, S., and Weaver, A. T.:
A 4D-Var Analysis System for the California Current: A Prototype for an Operational Regional Ocean Data Assimilation System, in: Data Assimilation for Atmospheric, Oceanic and Hydrologic Applications (Vol. II), edited by: Park, S. K. and Xu, L., chap. 14, pp. 345–366, Springer Berlin Heidelberg, Berlin, Heidelberg, https://doi.org/10.1007/978-3-642-35088-7_14, 2013. a
Moore, A. M., Martin, M. J., Akella, S., Arango, H. G., Balmaseda, M., Bertino, L., Ciavatta, S., Cornuelle, B., Cummings, J., Frolov, S., Lermusiaux, P., Oddo, P., Oke, P. R., Storto, A., Teruzzi, A., Vidard, A., and Weaver, A. T.:
Synthesis of Ocean Observations Using Data Assimilation for Operational, Real-Time and Reanalysis Systems: A More Complete Picture of the State of the Ocean, Frontiers in Marine Science, 6, https://doi.org/10.3389/fmars.2019.00090, 2019. a
Moore, A. M., Zavala-Garay, J., Arango, H. G., Edwards, C. A., Anderson, J., and Hoar, T.:
Regional and basin scale applications of ensemble adjustment Kalman filter and 4D-Var ocean data assimilation systems, Prog. Oceanogr., 189, 102450, https://doi.org/10.1016/j.pocean.2020.102450, 2020. a
O'Kane, T. J., Oke, P. R., and Sandery, P. A.:
Predicting the East Australian Current, Ocean Modell., 38, 251–266, https://doi.org/10.1016/j.ocemod.2011.04.003, 2011. a
Oke, P. R. and Schiller, A.:
A Model-Based Assessment and Design of a Tropical Indian Ocean Mooring Array, J. Climate, 20, 3269–3283, https://doi.org/10.1175/jcli4170.1, 2007. a
Oke, P. R., Roughan, M., Cetina-Heredia, P., Pilo, G. S., Ridgway, K. R., Rykova, T., Archer, M. R., Coleman, R. C., Kerry, C. G., Rocha, C., Schaeffer, A., and Vitarelli, E.:
Revisiting the circulation of the East Australian Current: Its path, separation, and eddy field, Prog. Oceanogr., 176, 102139, https://doi.org/10.1016/j.pocean.2019.102139, 2019. a, b, c, d
Oliver, E. C. J., Donat, M. G., Burrows, M. T., Moore, P. J., Smale, D. A., Alexander, L. V., Benthuysen, J. A., Feng, M., Gupta, A. S., Hobday, A. J., Holbrook, N. J., Perkins-Kirkpatrick, S. E., Scannell, H. A., Straub, S. C., and Wernberg, T.:
Longer and more frequent marine heatwaves over the past century, Nat. Commun., 9, 1324, https://doi.org/10.1038/s41467-018-03732-9, 2018. a
Puri, K., Dietachmayer, G., Steinle, P., Dix, M., Rikus, L., Logan, L., Naughton, M., Tingwell, C., Xiao, Y., Barras, V., Bermous, I. Bowen, R., Deschamps, L., Franklin, C., Fraser, J., Glowacki, T., Harris, B., Lee, J., Le, T., Roff, G., Sulaiman, A., Sims, H., Sun, X., Sun, Z., Zhu, H., Chattopadhyay, M., Engel, C.: Implementation of the initial ACCESS numerical weather prediction system, Aust. Meteorol. Ocean., 63, 265–284, 2013. a
Research Technology Services, UNSW Sydney:
Katana computational cluster, https://doi.org/10.26190/669x-a286, 2022. a
Ribbat, N., Roughan, M., Powell, B., Rao, S., and Kerry, C. G.:
Transport variability over the Hawkesbury Shelf (31.5–34.5∘ S) driven by the East Australian Current, PLOS ONE, 15, e0241622, https://doi.org/10.1371/journal.pone.0241622, 2020. a
Richardson, P. L. and Knauss, J. A.:
Gulf stream and Western boundary undercurrent observations at Cape Hatteras, Deep Sea Research and Oceanographic Abstracts, 18, 1089–1109, https://doi.org/10.1016/0011-7471(71)90095-7, 1971. a
Roughan, M., Schaeffer, A., and Suthers, I. M.:
Sustained Ocean Observing along the Coast of Southeastern Australia: NSW-IMOS 2007–2014, in: Coastal Ocean Observing Systems, edited by: Liu, Y., Kerkering, H., and Weisberg, R. H., Elsevier, Boston, 76–98, ISBN 978-0-12-802022-7, https://doi.org/10.1016/b978-0-12-802022-7.00006-7, 2015. a
Roughan, M., Cetina-Heredia, P., Ribbat, N., and Suthers, I. M.:
Shelf Transport Pathways Adjacent to the East Australian Current Reveal Sources of Productivity for Coastal Reefs, Frontiers in Marine Science, 8, https://doi.org/10.3389/fmars.2021.789687, 2022. a
Schiller, A., Wijffels, S. E., and Meyers, G. A.:
Design Requirements for an Argo Float Array in the Indian Ocean Inferred from Observing System Simulation Experiments, J. Atmos. Ocean. Tech., 21, 1598–1620, https://doi.org/10.1175/1520-0426(2004)021<1598:drfaaf>2.0.co;2, 2004. a
Siripatana, A., Kerry, C., Roughan, M., Souza, J. M. A. C., and Keating, S.:
Assessing the Impact of Nontraditional Ocean Observations for Prediction of the East Australian Current, J. Geophys. Res.-Oceans, 125, e2020JC016580, https://doi.org/10.1029/2020jc016580, 2020. a, b, c, d
Su, C.-H., Eizenberg, N., Steinle, P., Jakob, D., Fox-Hughes, P., White, C. J., Rennie, S., Franklin, C., Dharssi, I., and Zhu, H.:
BARRA v1.0: the Bureau of Meteorology Atmospheric high-resolution Regional Reanalysis for Australia, Geosci. Model Dev., 12, 2049–2068, https://doi.org/10.5194/gmd-12-2049-2019, 2019. a, b
Todd, R. E., Chavez, F. P., Clayton, S., Cravatte, S., Goes, M., Graco, M., Lin, X., Sprintall, J., Zilberman, N. V., Archer, M., Arístegui, J., Balmaseda, M., Bane, J. M., Baringer, M. O., Barth, J. A., Beal, L. M., Brandt, P., Calil, P. H. R., Campos, E., Centurioni, L. R., Chidichimo, M. P., Cirano, M., Cronin, M. F., Curchitser, E. N., Davis, R. E., Dengler, M., deYoung, B., Dong, S., Escribano, R., Fassbender, A. J., Fawcett, S. E., Feng, M., Goni, G. J., Gray, A. R., Gutiérrez, D., Hebert, D., Hummels, R., ichi Ito, S., Krug, M., Lacan, F., Laurindo, L., Lazar, A., Lee, C. M., Lengaigne, M., Levine, N. M., Middleton, J., Montes, I., Muglia, M., Nagai, T., Palevsky, H. I., Palter, J. B., Phillips, H. E., Piola, A., Plueddemann, A. J., Qiu, B., Rodrigues, R. R., Roughan, M., Rudnick, D. L., Rykaczewski, R. R., Saraceno, M., Seim, H., Gupta, A. S., Shannon, L., Sloyan, B. M., Sutton, A. J., Thompson, L., van der Plas, A. K., Volkov, D., Wilkin, J., Zhang, D., and Zhang, L.:
Global Perspectives on Observing Ocean Boundary Current Systems, Frontiers in Marine Science, 6, https://doi.org/10.3389/fmars.2019.00423, 2019. a
Whiteway, T.:
Australian bathymetry and topography grid, June 2009, Record 2009/021, Geoscience Australia, Canberra, Australia, Department of Industry [data set], https://doi.org/10.4225/25/53D99B6581B9A, 2009. a
Wu, L., Cai, W., Zhang, L., Nakamura, H., Timmermann, A., Joyce, T., McPhaden, M. J., Alexander, M., Qiu, B., Visbeck, M., Chang, P., and Giese, B.:
Enhanced warming over the global subtropical western boundary currents, Nat. Clim. Change, 2, 161–166, https://doi.org/10.1038/nclimate1353, 2012. a
Yang, H., Lohmann, G., Krebs-Kanzow, U., Ionita, M., Shi, X., Sidorenko, D., Gong, X., Chen, X., and Gowan, E. J.:
Poleward Shift of the Major Ocean Gyres Detected in a Warming Climate, Geophys. Res. Lett., 47, e2019GL085868, https://doi.org/10.1029/2019gl085868, 2020. a
Yang, M., Guan, L., Beggs, H., Morgan, N., Kurihara, Y., and Kachi, M.:
Comparison of Himawari-8 AHI SST with Shipboard Skin SST Measurements in the Australian Region, Remote Sensing, 12, 1237, https://doi.org/10.3390/rs12081237, 2020. a
Zavala-Garay, J., Wilkin, J. L., and Arango, H. G.:
Predictability of Mesoscale Variability in the East Australian Current Given Strong-Constraint Data Assimilation, J, Phys. Oceanogr., 42, 1402–1420, https://doi.org/10.1175/jpo-d-11-0168.1, 2012. a
Zeng, X., Adams, A., Roffer, M., and He, R.:
Potential connectivity among spatially distinct management zones for Bonefish (Albula vulpes) via larval dispersal, Environ. Biol. Fish., 102, 233–252, https://doi.org/10.1007/s10641-018-0826-z, 2018. a
Zhang, W. G., Wilkin, J. L., and Arango, H. G.:
Towards an integrated observation and modeling system in the New York Bight using variational methods. Part I: 4DVAR data assimilation, Ocean Modell., 35, 119–133, https://doi.org/10.1016/j.ocemod.2010.08.003, 2010. a
Short summary
The ocean current flowing along the southeastern coast of Australia is called the East Australian Current (EAC). Using computer simulations, we tested how surface and subsurface observations might improve models of the EAC. Subsurface observations are particularly important for improving simulations, and if made in the correct location and time, can have impact 600 km upstream. The stability of the current affects model estimates could be capitalized upon in future observing strategies.
The ocean current flowing along the southeastern coast of Australia is called the East...
