Assimilation of Ice Concentration Data through a Strongly Coupled Regime in the Arctic Ocean Model
M. N. Kaurkin1, ✉, L. Yu. Kalnitskii1, K. V. Ushakov1, R. A. Ibrayev1, 2
1 Shirshov Institute of Oceanology, Russian Academy of Sciences, Moscow, Russian Federation
2 Marchuk Institute of Numerical Mathematics, Russian Academy of Sciences, Moscow, Russian Federation
✉ e-mail: kaurkin.mn@ocean.ru
Abstract
Purpose. The purpose of this study is to develop and implement a strongly coupled approach to the assimilation of available observational data in a coupled ocean-sea ice circulation model, and to test it for the Arctic region.
Methods and Results. In the coupled INMIO (ocean) and CICE 5.1 (ice) model at 0.25° resolution, the data were assimilated using the Compact Modeling Framework (CMF3.0) platform with the DAS (Data Assimilation Service) software based on the EnOI (Ensemble Optimal Interpolation) method. A strongly coupled assimilation approach was applied. This approach involves simultaneous adjustment of the fields of water temperature, salinity, sea level, and ice concentration using observational data (ARGO profiles, AVISO satellite altimetry, and OSI SAF ice concentration). A specialized interface was developed to redistribute the integrated ice concentration among the ice thickness categories. Numerical experiments with and without data assimilation were performed for 2020. It is shown that data assimilation through a strongly coupled regime reduces the average error in reproducing the ice area from 27 to 7% as compared to the NSIDC data. The standard error of ocean surface water temperature is reduced to 1.0 °C, and that of ice concentration in the edge area to 0.2. The model fields correspond better to the independent OSTIA data.
Conclusions. The developed approach to the strongly coupled assimilation of oceanic and ice data in the coupled ocean-ice model provides a significant increase in the accuracy of forecasting the condition both of the water and the ice field in the Arctic Ocean. The software can be adapted to other models.
Keywords
computer modeling, numerical modeling, data assimilation, ocean dynamics model, ocean-ice model, parallel computing, Arctic region, sea ice cover
Acknowledgements
The study was carried out at the Shirshov Institute of Oceanology, Russian Academy of Sciences, with financial support of the Russian Science Foundation (grant No. 25-27-00400).
About the authors
Maksim N. Kaurkin, Researcher, Ocean and Sea Climate Variability Modeling Group, Shirshov Institute of Oceanology, Russian Academy of Sciences (36 Nakhimovsky Ave., Moscow, 117997, Russian Federation), CSc. (Phys.-Math.), SPIN-code: 8374-6238, Scopus Author ID: 57190488613, ORCID ID: 0000-0002-0921-3630, ResearcherID: S-1416-2016, kaurkin.mn@ocean.ru
Leonid Yu. Kalnitskii, Leading Engineer, Ocean and Sea Climate Variability Modeling Group, Shirshov Institute of Oceanology, Russian Academy of Sciences (36, Nakhimovsky Prospekt, Moscow, 117997, Russian Federation), Scopus Author ID: 57219609143, ORCID ID: 0009-0005-4023-2257, leonid.kalnitsckij@yandex.ru
Konstantin V. Ushakov, Senior Research Associate, Ocean and Sea Climate Variability Modeling Group, Shirshov Institute of Oceanology, Russian Academy of Sciences (36 Nakhimovsky Ave., Moscow, 117997, Russian Federation), CSc. (Phys.-Math.), SPIN-code: 6997-1295, Scopus Author ID: 55015342700, ORCID ID: 0000-0002-8454-9927, ResearcherID: U-6185-2017, ushakovkv@mail.ru
Rashit A. Ibrayev, Chief Researcher, Marchuk Institute of Numerical Mathematics, Russian Academy of Sciences (8 Gubkina Str., Moscow, 119333, Russian Federation); Shirshov Institute of Oceanology, Russian Academy of Sciences (36 Nakhimovsky Ave., Moscow, 117997, Russian Federation), DSc. (Phys.-Math.), Corresponding Member of RAS, SPIN-code: 9003-9192, Scopus Author ID: 6602387822, ResearcherID: S-6750-2016, ORCID ID: 0000-0002-9099-4541, ibrayev@mail.ru
Original russian text
Original Russian Text © The Authors, 2026, published in MORSKOY GIDROFIZICHESKIY ZHURNAL, Vol. 42, Iss. 2, pp. 307–322 (2026)
For citation
Kaurkin, M.N., Kalnitskii, L.Yu., Ushakov, K.V. and Ibrayev, R.A., 2025. Assimilation of Ice Concentration Data through a Strongly Coupled Regime in the Arctic Ocean Model. Physical Oceanography, 33(2), pp. 352-365.
References
- Guemas, V., Blanchard‐Wrigglesworth, E., Chevallier, M., Day, J.J., Déqué, M., Doblas‐Reyes, F.J., Fučkar, N.S., Germe, A., Hawkins, E. [et al.], 2016. A Review on Arctic Sea-Ice Predictability and Prediction on Seasonal to Decadal Time-Scales. Quarterly Journal of the Royal Meteorological Society, 142(695), pp. 546-561. https://doi.org/10.1002/qj.2401
- Skachko, S., Buehner, M., Laroche, S., Lapalme, E., Smith, G., Roy, F., Surcel-Colan, D., Bélanger, J.-M. and Garand, L., 2019. Weakly Coupled Atmosphere–Ocean Data Assimilation in the Canadian Global Prediction System (v1). Geoscientific Model Development, 12(12), pp. 5097-5112. https://doi.org/10.5194/gmd-12-5097-2019
- Brassington, G.B., Martin, M.J., Tolman, H.I., Akella, S., Balmeseda, M., Chambers, C.R.S., Chassignet, E., Cummings, J.A., Drillet, Y. [et al.], 2015. Progress and Challenges in Short- to Medium-Range Coupled Prediction. Journal of Operational Oceanography, 8(S2), pp. s239-s258. https://doi.org/10.1080/1755876X.2015.1049875
- Penny, S.G. and Hamill, T.M., 2017. Coupled Data Assimilation for Integrated Earth System Analysis and Prediction. Bulletin of the American Meteorological Society, 98(7), pp. ES169-ES172. https://doi.org/10.1175/BAMS-D-17-0036.1
- Kimmritz, M., Counillon, F., Bitz, C.M., Massonnet, F., Bethke, I. and Gao, Y., 2018. Optimising Assimilation of Sea Ice Concentration in an Earth System Model with a Multicategory Sea Ice Model. Tellus A: Dynamic Meteorology and Oceanography, 70(1), 1435945. https://doi.org/10.1080/16000870.2018.1435945
- Fomin, V.V. and Diansky, N.A., 2023. Methods of Assimilation of Sea Surface Temperature Satellite Data and Their Influence on the Reconstruction of Hydrophysical Fields of the Black, Azov, and Marmara Seas Using the Institute of Numerical Mathematics Ocean Model (INMOM). Russian Meteorology and Hydrology, 48(2), pp. 97-108. https://doi.org/10.3103/S1068373923020024
- Ibrayev, R.A., Khabeev, R.N. and Ushakov, K.V., 2012. Eddy-Resolving 1/10° Model of the World Ocean. Izvestiya, Atmospheric and Oceanic Physics, 48(1), pp. 37-46. https://doi.org/10.1134/S0001433812010045
- Kalmykov, V.V., Ibrayev, R.A., Kaurkin, M.N. and Ushakov, K.V., 2018. Compact Modeling Framework v3.0 for High-Resolution Global Ocean–Ice–Atmosphere Models. Geoscientific Model Development, 11(10), pp. 3983-3997. https://doi.org/10.5194/gmd-11-3983-2018
- Kalnitskii, L.Y., Kaurkin, M.N., Ushakov, K.V. and Ibrayev, R.A., 2020. Seasonal Variability of Water and Sea-Ice Circulation in the Arctic Ocean in a High-Resolution Model. Izvestiya, Atmospheric and Oceanic Physics, 56(5), pp. 522-533. https://doi.org/10.1134/S0001433820050060
- Murray, R.J., 1996. Explicit Generation of Orthogonal Grids for Ocean Models. Journal of Computational Physics, 126(2), pp. 251-273. https://doi.org/10.1006/jcph.1996.0136
- Fadeev, R., Ushakov, K., Tolstykh, M., Ibrayev, R., Shashkin, V. and Goyman, G., 2019. Supercomputing the Seasonal Weather Prediction. In: V. Voevodin and S. Sobolev, eds., 2019. Supercomputing. Cham: Springer, pp. 415-426. https://doi.org/10.1007/978-3-030-36592-9_34
- Griffies, S.M. and Hallberg, R.W., 2000. Biharmonic Friction with a Smagorinsky-Like Viscosity for Use in Large-Scale Eddy-Permitting Ocean Models. Monthly Weather Review, 128(8), pp. 2935-2946. https://doi.org/10.1175/1520-0493(2000)128%3C2935:BFWASL%3E2.0.CO;2
- Dussin, R., Treguier, A.M., Molines, J.M., Barnier, B., Penduff, T., Brodeau, L. and Madec, G., 2009. Definition of the Interannual Experiment ORCA025-B83, 1958-2007. LPO Report 09-02. Brest, France: Laboratoire de Physique des Oceans, 37 p.
- Zalesak, S.T., 1979. Fully Multidimensional Flux-Corrected Transport Algorithms for Fluids. Journal of Computational Physics, 31(3), pp. 335-362. https://doi.org/10.1016/0021-9991(79)90051-2
- Launiainen, J. and Vihma, T., 1990. Derivation of Turbulent Surface Fluxes – An Iterative Flux-Profile Method Allowing Arbitrary Observing Heights. Environmental Software, 5(3), pp. 113-124. https://doi.org/10.1016/0266-9838(90)90021-W
- Sakov, P., Counillon, F., Bertino, L., Lisæter, K.A., Oke, P.R. and Korablev, A., 2012. TOPAZ4: An Ocean-Sea Ice Data Assimilation System for the North Atlantic and Arctic. Ocean Science, 8(4), pp. 633-656. https://doi.org/10.5194/os-8-633-2012
- Dee, D.P., Uppala, S.M., Simmons, A.J., Berrisford, P., Poli, P., Kobayashi, S., Andrae, U., Balmaseda, M.A., Balsamo, G. [et al.], 2011. The ERA-Interim Reanalysis: Configuration and Performance of the Data Assimilation System. Quarterly Journal of the Royal Meteorological Society, 137(656), pp. 553-597. https://doi.org/10.1002/qj.828
- Evensen, G., 2006. Data Assimilation: The Ensemble Kalman Filter. Berlin; Heidelberg: Springer-Verlag, 307 p. https://doi.org/10.1007/978-3-642-03711-5
- Evensen, G., 2003. The Ensemble Kalman Filter: Theoretical Formulation and Practical Implementation. Ocean Dynamics, 53(4), pp. 343-367. https://doi.org/10.1007/s10236-003-0036-9
- Kaurkin, M., Ibrayev, R. and Koromyslov, A., 2016. EnOI-Based Data Assimilation Technology for Satellite Observations and ARGO Float Measurements in a High Resolution Global Ocean Model Using the CMF Platform. In: V. Voevodin and S. Sobolev, eds., 2016. Supercomputing. Cham: Springer, pp. 57-66. https://doi.org/10.1007/978-3-319-55669-7_5
- Sakov, P. and Sandery, P.A., 2015. Comparison of EnOI and EnKF Regional Ocean Reanalysis Systems. Ocean Modelling, 89, pp. 45-60. https://doi.org/10.1016/j.ocemod.2015.02.003
- Oke, P.R., Brassington, G.B., Griffin, D.A. and Schiller, A., 2010. Ocean Data Assimilation: A Case for Ensemble Optimal Interpolation. Australian Meteorological and Oceanographic Journal, 59, pp. 67-76.
- Kaurkin, M.N., Ibrayev, R.A. and Belyaev, K.P., 2016. ARGO Data Assimilation into the Ocean Dynamics Model with High Spatial Resolution Using Ensemble Optimal Interpolation (EnOI). Oceanology, 56(6), pp. 774-781. https://doi.org/10.1134/S0001437016060059
- Good, S., Fiedler, E., Mao, C., Martin, M.J., Maycock, A., Reid, R., Roberts-Jones, J., Searle, T., Waters, J. [et al.], 2020. The Current Configuration of the OSTIA System for Operational Production of Foundation Sea Surface Temperature and Ice Concentration Analyses. Remote Sensing, 12(4), 720. https://doi.org/10.3390/rs12040720
- Melsom, A., Palerme, C. and Müller, M., 2019. Validation Metrics for Ice Edge Position Forecasts. Ocean Science, 15(3), pp. 615-630. https://doi.org/10.5194/os-15-615-2019
- Fanjul, E.A., Ciliberti, S.A., Bahurel, P., Aouf, L., Bertino, L., Coppini, G., Diaz-Hernandez, G., Davidson, F., Gutknecht, E. [et al.], 2022. Implementing Operational Ocean Monitoring and Forecasting Systems. Paris, France: IOC-UNESCO, 376 p. https://doi.org/10.48670/ETOOFS
- Kalnay, E., Sluka, T., Yoshida, T., Da, C. and Mote, S., 2023. Review Article: Towards Strongly Coupled Ensemble Data Assimilation with Additional Improvements from Machine Learning. Nonlinear Processes in Geophysics, 30(2), pp. 217-236. https://doi.org/10.5194/npg-30-217-2023