Articles | Volume 19, issue 1
https://doi.org/10.5194/gmd-19-187-2026
© Author(s) 2026. 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-19-187-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Model experiment description paper
| 
07 Jan 2026
Model experiment description paper |
| 07 Jan 2026
| 07 Jan 2026
Assessing vertical coordinate system performance in the Regional Modular Ocean Model 6 configuration for Northwest Pacific
Inseong Chang
Division of Earth Environmental System Science, Pukyong National University, Busan, Republic of Korea
Ocean Circulation and Climate Research Department, Korea Institute of Ocean Sciences and Technology, Busan, Republic of Korea
Division of Earth Environmental System Science, Pukyong National University, Busan, Republic of Korea
Young-Gyu Park
Ocean Circulation and Climate Research Department, Korea Institute of Ocean Sciences and Technology, Busan, Republic of Korea
Hyunkeun Jin
Ocean Circulation and Climate Research Department, Korea Institute of Ocean Sciences and Technology, Busan, Republic of Korea
Gyundo Pak
Ocean Circulation and Climate Research Department, Korea Institute of Ocean Sciences and Technology, Busan, Republic of Korea
Andrew C. Ross
NOAA OAR Geophysical Fluid Dynamics Laboratory, Princeton, NJ, USA
Robert Hallberg
NOAA OAR Geophysical Fluid Dynamics Laboratory, Princeton, NJ, USA
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Nicole Cristine Laureanti, Enrique Curchitser, Katherine Hedstrom, Alistair Adcroft, Robert Hallberg, Matthew J. Harrison, Raphael Dussin, Sin Chan Chou, Paulo Nobre, Emanuel Giarolla, and Rosio Camayo
Geosci. Model Dev., 19, 3109–3128, https://doi.org/10.5194/gmd-19-3109-2026, https://doi.org/10.5194/gmd-19-3109-2026, 2026
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This study investigates the variability of currents in the Southwestern Atlantic Ocean using a high-resolution simulation. Particularly in the Brazil-Malvinas Confluence (BMC), it finds that the southward movement of the BMC, induced by the warming trends in the region, is balanced by northward flow from the Malvinas Current and Pacific Waves. The analysis also examines the intense northward displacement of the North Brazil Current, where inconsistencies in the simulation affect its evolution.
Inseong Chang, Young Ho Kim, Young-Gyu Park, Hyunkeun Jin, Gyundo Pak, Andrew C. Ross, and Robert Hallberg
Geosci. Model Dev., 19, 3053–3074, https://doi.org/10.5194/gmd-19-3053-2026, https://doi.org/10.5194/gmd-19-3053-2026, 2026
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This study assesses how vertical coordinate choice shapes barotropic and baroclinic tide simulations in a high-resolution, MOM6 (Modular Ocean Model version 6) regional model. Focusing on the Yellow Sea under realistic forcing and seasonal stratification, we compare z* and z*-isopycnal hybrid to quantify coordinate-dependent impacts on tidal energetics and vertical structure. The results underscore that vertical representation is critical for accurately reproducing coastal stratification and tide–stratification interactions.
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
The Cryosphere, 20, 2053–2088, https://doi.org/10.5194/tc-20-2053-2026, https://doi.org/10.5194/tc-20-2053-2026, 2026
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The second Ice Shelf-Ocean Model Intercomparison Project, ISOMIP+, compares 12 ice shelf-ocean models with a common, idealised, static configuration, aiming to assess inter-model variability. Models show similar basal melt rate patterns, ocean profiles and circulation but differ in ice-ocean boundary layer properties. Ice-ocean boundary layer representation is a key area for future work, as are realistic-domain ice sheet-ocean model intercomparisons.
Dmitry S. Dukhovskoy, Theresa Cordero, Katherine Hedstrom, Michael Alexander, Michael Jacox, Robert Hallberg, Matthew Harrison, and Jessie Liu
EGUsphere, https://doi.org/10.5194/egusphere-2026-955, https://doi.org/10.5194/egusphere-2026-955, 2026
This preprint is open for discussion and under review for Geoscientific Model Development (GMD).
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A method for improving sea ice simulations by adjusting ice cover and thickness using observations or analysis data has been implemented in a regional sea ice model. Tests show improved representation of ice along the edges and within the ice-covered area. This suggests the method can provide more accurate initial conditions for forecasts, which is important for predicting ocean, sea ice, and ecosystem conditions in polar regions.
Hong Thi My Tran, Young Gyu Park, and Jun Myoung Choi
EGUsphere, https://doi.org/10.5194/egusphere-2026-943, https://doi.org/10.5194/egusphere-2026-943, 2026
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This study examines debris transport in a semi-enclosed marginal sea using 25 satellite-tracked surface drifters deployed in late autumn. All drifters followed a consistent pathway and beached along the southeastern boundary. By testing geostrophic currents, windage, Ekman currents, and Stokes drift, we identified the most accurate surface forcing scheme, highlighting the value of in situ observations for improving transport modelling and seasonal prediction.
Vimal Koul, Andrew Ross, Charles Stock, Liping Zhang, Andrew Wittenberg, and Thomas Delworth
EGUsphere, https://doi.org/10.5194/egusphere-2026-481, https://doi.org/10.5194/egusphere-2026-481, 2026
This preprint is open for discussion and under review for Ocean Science (OS).
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Predicting coastal ocean conditions years ahead has been difficult due to complex regional dynamics. This work shows we can forecast bottom temperature, oxygen, and acidity up to a decade ahead for the Northeast U.S. Shelf. Our forecasts indicate increasing Labrador water may accelerate acidification, threatening shell-forming organisms. This provides a foundation for early warning systems to help communities and fisheries adapt proactively.
Meena Raju, David J. Cannon, Peter Alsip, He Wang, Jia Wang, Theresa Cordero, Robert W. Hallberg, Charles A. Stock, and Joseph A. Langan
EGUsphere, https://doi.org/10.5194/egusphere-2025-6556, https://doi.org/10.5194/egusphere-2025-6556, 2026
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This study developed the Modular Ocean Model version 6.0 coupled with Sea Ice Simulator version 2.0 for the Great Lakes, validated against observations and an operational model. This study also tested two vertical coordinate systems, z* and hybrid. The model reproduced lake physics with good skill. The hybrid vertical coordinate improved thermocline representation and preserved deep cold-water during stratification, demonstrating the model’s suitability for large freshwater systems.
Dongmin Kim, Andrew C. Ross, Sang-Ik Shin, Fabian A. Gomez, Jasmin G. John, Denis L. Volkov, Sang-Ki Lee, Michael A. Alexander, and Charles A. Stock
EGUsphere, https://doi.org/10.5194/egusphere-2025-6449, https://doi.org/10.5194/egusphere-2025-6449, 2026
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Using high-resolution MOM6, we projected Northwest Atlantic changes under four SSP scenarios. Results show a weakening Gulf Stream reduces upwelling, causing significant shelf warming and salinification. This also leads to dynamic sea-level rise along the U.S. East Coast, particularly in the South Atlantic Bight, with critical implications for marine ecosystems and coastal risks.
Enhui Liao, Laure Resplandy, Fan Yang, Yangyang Zhao, Sam Ditkovsky, Manon Malsang, Jenna Pearson, Andrew C. Ross, Robert Hallberg, and Charles Stock
Geosci. Model Dev., 18, 6553–6596, https://doi.org/10.5194/gmd-18-6553-2025, https://doi.org/10.5194/gmd-18-6553-2025, 2025
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The northern Indian Ocean is central to the livelihoods and economies of countries that comprise about one-third of the world's population. We present a high-resolution (~10 km) ocean model that simulates seasonal and year-to-year variability in ocean, including currents, oxygen levels, and phytoplankton growth. This model is a powerful tool to study how climate change and human activities influence the northern Indian Ocean, which can be used for marine resource applications and management.
Elizabeth J. Drenkard, Charles A. Stock, Andrew C. Ross, Yi-Cheng Teng, Theresa Cordero, Wei Cheng, Alistair Adcroft, Enrique Curchitser, Raphael Dussin, Robert Hallberg, Claudine Hauri, Katherine Hedstrom, Albert Hermann, Michael G. Jacox, Kelly A. Kearney, Rémi Pagès, Darren J. Pilcher, Mercedes Pozo Buil, Vivek Seelanki, and Niki Zadeh
Geosci. Model Dev., 18, 5245–5290, https://doi.org/10.5194/gmd-18-5245-2025, https://doi.org/10.5194/gmd-18-5245-2025, 2025
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We made a new regional ocean model to assist fisheries and ecosystem managers in making decisions in the Northeast Pacific Ocean (NEP). We found that the model did well simulating past ocean conditions like temperature and nutrient and oxygen levels and can even reproduce metrics used by, and important to, ecosystem managers.
Andrew C. Ross, Charles A. Stock, Vimal Koul, Thomas L. Delworth, Feiyu Lu, Andrew Wittenberg, and Michael A. Alexander
Ocean Sci., 20, 1631–1656, https://doi.org/10.5194/os-20-1631-2024, https://doi.org/10.5194/os-20-1631-2024, 2024
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In this paper, we use a high-resolution regional ocean model to downscale seasonal ocean forecasts from the Seamless System for Prediction and EArth System Research (SPEAR) model of the Geophysical Fluid Dynamics Laboratory (GFDL). We find that the downscaled model has significantly higher prediction skill in many cases.
Andrew C. Ross, Charles A. Stock, Alistair Adcroft, Enrique Curchitser, Robert Hallberg, Matthew J. Harrison, Katherine Hedstrom, Niki Zadeh, Michael Alexander, Wenhao Chen, Elizabeth J. Drenkard, Hubert du Pontavice, Raphael Dussin, Fabian Gomez, Jasmin G. John, Dujuan Kang, Diane Lavoie, Laure Resplandy, Alizée Roobaert, Vincent Saba, Sang-Ik Shin, Samantha Siedlecki, and James Simkins
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We evaluate a model for northwest Atlantic Ocean dynamics and biogeochemistry that balances high resolution with computational economy by building on the new regional features in the MOM6 ocean model and COBALT biogeochemical model. We test the model's ability to simulate impactful historical variability and find that the model simulates the mean state and variability of most features well, which suggests the model can provide information to inform living-marine-resource applications.
Fabian A. Gomez, Sang-Ki Lee, Charles A. Stock, Andrew C. Ross, Laure Resplandy, Samantha A. Siedlecki, Filippos Tagklis, and Joseph E. Salisbury
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We present a river chemistry and discharge dataset for 140 rivers in the United States, which integrates information from the Water Quality Database of the US Geological Survey (USGS), the USGS’s Surface-Water Monthly Statistics for the Nation, and the U.S. Army Corps of Engineers. This dataset includes dissolved inorganic carbon and alkalinity, two key properties to characterize the carbonate system, as well as nutrient concentrations, such as nitrate, phosphate, and silica.
Gustavo M. Marques, Nora Loose, Elizabeth Yankovsky, Jacob M. Steinberg, Chiung-Yin Chang, Neeraja Bhamidipati, Alistair Adcroft, Baylor Fox-Kemper, Stephen M. Griffies, Robert W. Hallberg, Malte F. Jansen, Hemant Khatri, and Laure Zanna
Geosci. Model Dev., 15, 6567–6579, https://doi.org/10.5194/gmd-15-6567-2022, https://doi.org/10.5194/gmd-15-6567-2022, 2022
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We present an idealized ocean model configuration and a set of simulations performed using varying horizontal grid spacing. While the model domain is idealized, it resembles important geometric features of the Atlantic and Southern oceans. The simulations described here serve as a framework to effectively study mesoscale eddy dynamics, to investigate the effect of mesoscale eddies on the large-scale dynamics, and to test and evaluate eddy parameterizations.
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Short summary
We conducted sensitivity experiments to examine how different vertical coordinates influence the representation of water masses and tides using a high-resolution regional ocean model for the Northwest Pacific. We found that the choice of vertical coordinate strongly affects the degree of artificial mixing, which in turn changes how well the model reproduces key ocean features. This highlights the importance of selecting a vertical coordinate when developing regional ocean models.
We conducted sensitivity experiments to examine how different vertical coordinates influence the...
