Articles | Volume 17, issue 10
https://doi.org/10.5194/tc-17-4487-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-17-4487-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Local analytical optimal nudging for assimilating AMSR2 sea ice concentration in a high-resolution pan-Arctic coupled ocean (HYCOM 2.2.98) and sea ice (CICE 5.1.2) model
Division of Ocean and Ice, Norwegian Meteorological Institute, Oslo, Norway
Alfatih Ali
Division of Ocean and Ice, Norwegian Meteorological Institute, Bergen, Norway
Caixin Wang
Division of Ocean and Ice, Norwegian Meteorological Institute, Oslo, Norway
Related authors
Fangru Mu, Chengfei Jiang, Bin Cheng, Keguang Wang, Caixin Wang, Yuhan Chen, Zhiyuan Shao, and Jiechen Zhao
EGUsphere, https://doi.org/10.5194/egusphere-2025-3214, https://doi.org/10.5194/egusphere-2025-3214, 2025
This preprint is open for discussion and under review for The Cryosphere (TC).
Short summary
Short summary
Icebergs pose risks to ships and are an important part of the polar environment. We developed an iceberg detection algorithm based on the Swin transformer model (IDAS-Transformer). The IDAS-Transformer is capable of handling complex surface characteristic mixtures, including fast ice, pack ice, and open water, to identify icebergs.
Johannes Röhrs, Yvonne Gusdal, Edel S. U. Rikardsen, Marina Durán Moro, Jostein Brændshøi, Nils Melsom Kristensen, Sindre Fritzner, Keguang Wang, Ann Kristin Sperrevik, Martina Idžanović, Thomas Lavergne, Jens Boldingh Debernard, and Kai H. Christensen
Geosci. Model Dev., 16, 5401–5426, https://doi.org/10.5194/gmd-16-5401-2023, https://doi.org/10.5194/gmd-16-5401-2023, 2023
Short summary
Short summary
A model to predict ocean currents, temperature, and sea ice is presented, covering the Barents Sea and northern Norway. To quantify forecast uncertainties, the model calculates ensemble forecasts with 24 realizations of ocean and ice conditions. Observations from satellites, buoys, and ships are ingested by the model. The model forecasts are compared with observations, and we show that the ocean model has skill in predicting sea surface temperatures.
Pedro Duarte, Jostein Brændshøi, Dmitry Shcherbin, Pauline Barras, Jon Albretsen, Yvonne Gusdal, Nicholas Szapiro, Andreas Martinsen, Annette Samuelsen, Keguang Wang, and Jens Boldingh Debernard
Geosci. Model Dev., 15, 4373–4392, https://doi.org/10.5194/gmd-15-4373-2022, https://doi.org/10.5194/gmd-15-4373-2022, 2022
Short summary
Short summary
Sea ice models are often implemented for very large domains beyond the regions of sea ice formation, such as the whole Arctic or all of Antarctica. In this study, we implement changes in the Los Alamos Sea Ice Model, allowing it to be implemented for relatively small regions within the Arctic or Antarctica and yet considering the presence and influence of sea ice outside the represented areas. Such regional implementations are important when spatially detailed results are required.
Fangru Mu, Chengfei Jiang, Bin Cheng, Keguang Wang, Caixin Wang, Yuhan Chen, Zhiyuan Shao, and Jiechen Zhao
EGUsphere, https://doi.org/10.5194/egusphere-2025-3214, https://doi.org/10.5194/egusphere-2025-3214, 2025
This preprint is open for discussion and under review for The Cryosphere (TC).
Short summary
Short summary
Icebergs pose risks to ships and are an important part of the polar environment. We developed an iceberg detection algorithm based on the Swin transformer model (IDAS-Transformer). The IDAS-Transformer is capable of handling complex surface characteristic mixtures, including fast ice, pack ice, and open water, to identify icebergs.
Johannes Röhrs, Yvonne Gusdal, Edel S. U. Rikardsen, Marina Durán Moro, Jostein Brændshøi, Nils Melsom Kristensen, Sindre Fritzner, Keguang Wang, Ann Kristin Sperrevik, Martina Idžanović, Thomas Lavergne, Jens Boldingh Debernard, and Kai H. Christensen
Geosci. Model Dev., 16, 5401–5426, https://doi.org/10.5194/gmd-16-5401-2023, https://doi.org/10.5194/gmd-16-5401-2023, 2023
Short summary
Short summary
A model to predict ocean currents, temperature, and sea ice is presented, covering the Barents Sea and northern Norway. To quantify forecast uncertainties, the model calculates ensemble forecasts with 24 realizations of ocean and ice conditions. Observations from satellites, buoys, and ships are ingested by the model. The model forecasts are compared with observations, and we show that the ocean model has skill in predicting sea surface temperatures.
Pedro Duarte, Jostein Brændshøi, Dmitry Shcherbin, Pauline Barras, Jon Albretsen, Yvonne Gusdal, Nicholas Szapiro, Andreas Martinsen, Annette Samuelsen, Keguang Wang, and Jens Boldingh Debernard
Geosci. Model Dev., 15, 4373–4392, https://doi.org/10.5194/gmd-15-4373-2022, https://doi.org/10.5194/gmd-15-4373-2022, 2022
Short summary
Short summary
Sea ice models are often implemented for very large domains beyond the regions of sea ice formation, such as the whole Arctic or all of Antarctica. In this study, we implement changes in the Los Alamos Sea Ice Model, allowing it to be implemented for relatively small regions within the Arctic or Antarctica and yet considering the presence and influence of sea ice outside the represented areas. Such regional implementations are important when spatially detailed results are required.
Cited articles
Ali, A., Muller, M., Bertino, L., and Melson, A.: A high resolution three-dimensional model of ocean tides for the pan-arctic region, EGU General Assembly 2021, online, 19–30 April 2021, EGU21-2409, https://doi.org/10.5194/egusphere-egu21-2409, 2021. a
Anthes, R. A.: Data Assimilation and Initialization of Hurricane Prediction Models, J. Atmos. Sci., 31, 702–719, https://doi.org/10.1175/1520-0469(1974)031<0702:DAAIOH>2.0.CO;2, 1974. a, b
Berkman, P. A., Fiske, G., Lorenzini, D., Young, O. R., Pletnikoff, K., Grebmeier, J. M., Fernandez, L. M., Divine, L. M., Causey, D., Kapsar, K. E., and Jørgensen, L. L.: Satellite record of pan-Arctic maritime ship traffic, NOAA technical report OAR ARC, 22-10, https://doi.org/10.25923/mhrv-gr76, 2022. a
Blockley, E. W., Martin, M. J., McLaren, A. J., Ryan, A. G., Waters, J., Lea, D. J., Mirouze, I., Peterson, K. A., Sellar, A., and Storkey, D.: Recent development of the Met Office operational ocean forecasting system: an overview and assessment of the new Global FOAM forecasts, Geosci. Model Dev., 7, 2613–2638, https://doi.org/10.5194/gmd-7-2613-2014, 2014. a, b
Bouillon, S., Fichefet, T., Legat, V., and Madec, G.: The elastic-viscous-plastic method revisited, Ocean Model., 71, 1–12, 2013. a
Brasseur, P. and Verron, J.: The SEEK filter method for data assimilation in oceanography: a synthesis, Ocean Dynam., 56, 650–661, https://doi.org/10.1007/s10236-006-0080-3, 2006. a
Breivik, L., Carrieres, T., Eastwood, S., Fleming, A., Girard-Ardhuin, F., Karvonen, J., Kwok, R., Meier, W., Mäkynen, M., Pedersen, L., Sandven, S., Similä, M., and Tonboe, R.: Remote Sensing of Sea Ice, ESA Publication WPP-306, Venice, Italy, https://doi.org/10.5270/OceanObs09.cwp.11, 2009. a, b
Buehner, M., Caya, A., Pogson, L., Carrieres, T., and Pestieau, P.: A new environment Canada regional ice analysis system, Atmosphere-Ocean, 51, 18–34, https://doi.org/10.1080/07055900.2012.747171, 2013. a
Caya, A., Buehner, M., and Carrieres, T.: Analysis and forecasting of sea ice conditions with three-dimensional variational data assimilation and a coupled ice–ocean mode, J. Atmos. Ocean. Tech., 27, 353–369, https://doi.org/10.1175/2009jtecho701.1, 2010. a, b, c, d
Cohen, J., Zhang, X., Francis, J., Jung, T., Kwok, R., Overland, J., Ballinger, T. J., Bhatt, U. S., Chen, H. W., Coumou, D., Feldstein, S., Gu, H., Handorf, D., Henderson, G., Ionita, M., Kretschmer, M., Laliberte, F., Lee, S., Linderholm, H. W., Maslowski, W., Peings, Y., Pfeiffer, K., Rigor, I., Semmler, T., Stroeve, J., Taylor, P. C., Vavrus, S., Vihma, T., Wang, S., Wendisch, M., Wu, Y., and Yoon, J.: Divergent consensuses on Arctic amplification influence on midlatitude severe winter weather, Nat. Clim. Change, 10, 20–29, https://doi.org/10.1038/s41558-019-0662-y, 2020. a
Comiso, J. C.: Characteristics of arctic winter sea ice from satellite multispectral microwave observations, J. Geophys. Res., 91, 975–994, https://doi.org/10.1029/JC091iC01p00975, 1986. a
Comiso, J. C.: Large decadal decline of the Arctic multiyear ice cover, J. Cli., 25, 1176–1193, https://doi.org/10.1175/JCLI-D-11-00113.1, 2012. a
Constable, A., Harper, S., Dawson, J., Holsman, K., Mustonen, T., Piepenburg, D., and Rost, B.: Cross-Chapter Paper 6: Polar Region, Cambridge University Press, Cambridge, UK and New York, USA, https://doi.org/10.1017/9781009325844.023, 2022. a, b
Copernicus Marine Service: Global Ocean Physics Analysis and Forecast, Copernicus Marine Service [data set], https://doi.org/10.48670/moi-00016, May 2022a. a, b, c
Copernicus Marine Service: Arctic Ocean Physics Analysis and Forecast, Copernicus Marine Service [data set], https://doi.org/10.48670/moi-00001, last access: May 2022b. a, b
Copernicus Marine Service: Arctic Ocean Sea Ice Analysis and Forecast, Copernicus Marine Service [data set], https://doi.org/10.48670/moi-00004, last access: May 2022c. a, b
Copernicus Marine Service: Arctic Ocean – Sea Ice Concentration Charts – Svalbard and Greenland, Copernicus Marine Service [data set], https://doi.org/10.48670/moi-00128, last access: June 2022d. a, b
Copernicus Marine Service: Global Ocean-Real time in-situ observations objective analysis, Copernicus Marine Service [data set], https://doi.org/10.48670/moi-00037, last access: 15 November 2022e. a, b
Copernicus Marine Service: Arctic Ocean Tidal Analysis and Forecast, Copernicus Marine Service [data set], https://doi.org/10.48670/moi-00005, 2019. a
Dammann, D., Eicken, H., Mahoney, A., Meyer, F., and Betcher, S.: Assessing sea ice trafficability in a changing Arctic, Arctic, 71, 1–113, https://doi.org/10.14430/arctic4701, 2018. a
Drange, H. and Simonsen, K.: Formulation of air-sea fluxes in the ESOP2 version of MICOM, NERSC, Thornøhlensgt., 47, 5006 Bergen, Norway, 1996. a
Eicken, H.: Arctic sea ice needs better forecasts, Nature, 497, 431–433, https://doi.org/10.1038/497431a, 2013. a
Emmerson, C. and Lahn, G.: Arctic opening: Opportunity and risk in the high north, Lloyds Rep., http://library.arcticportal.org/id/eprint/1671 (last access: May 2022), 2012. a
Fairall, C. W., Bradley, E. F., E., H. J., Grachev, A. A., and Edson, J. B.: Bulk parameterization on air–sea fluxes: Updates and verification for the COARE algorithm, J. Climate, 16, 571–591, https://doi.org/10.1175/1520-0442(2003)016<0571:BPOASF>2.0.CO;2, 2003. a
Fichefet, T. and Morales Maqueda, M. A.: Sensitivity of a global sea ice model to the treatment of ice thermodynamics and dynamics, J. Geophys. Res.-Oceans, 102, 12609–12646, https://doi.org/10.1029/97JC00480, 1997. a
Gaillard, F., Reynaud, T., Thierry, V., Kolodziejczyk, N., and Von Schuckmann, K.: In-situ based reanalysis of the global ocean temperature and salinity with ISAS: variability of the heat content and steric height, J. Climate, 29, 1305–1323, https://doi.org/10.1175/JCLI-D-15-0028.1, 2016. a
Galloudec, O. L., Chune, S. L., Nouel, L., Fernandez, E., Derval, C., Tressol, M., Dussurget, R., Biardeau, A., and Tonani, M.: Product User Manual for Global Ocean Physical Analysis and Forecasting Product GLOBAL_ANALYSISFORECAST_PHY_001_024, 1.9, Copernicus Marine Service, https://catalogue.marine.copernicus.eu/documents/PUM/CMEMS-GLO-PUM-001-024.pdf (last access: May 2022), 2022. a
Goessling, H. F., Tietsche, S., Day, J. J., Hawkins, E., and Jung, T.: Predictability of the Arctic sea ice edge, Geophys. Res. Lett., 43, 1642–1650, https://doi.org/10.1002/2015GL067232, 2016. a, b
Hackett, B., Bertino, L., Ali, A., Burud, A., Williams, T., Xie, J., Yumruktepe, C., Wakamatsu, T., and Melsom, A.: PRODUCT USER MANUAL For Arctic Ocean Physical and BGC Analysis and Forecasting Products ARCTIC_ANALYSIS_FORECAST_PHY_002_001_a, Issue: 5.15, Copernicus Marine Service, https://catalogue.marine.copernicus.eu/documents/PUM/CMEMS-ARC-PUM-002-ALL.pdf (last access: May 2022), 2022. a, b, c, d, e
Hibler, W. D.: A dynamic thermodynamic sea ice model, J. Phys. Oceanogr., 9, 817–846, https://doi.org/10.1175/1520-0485(1979)009<0815:ADTSIM>2.0.CO;2, 1979. a
Hibler, W. D.: Modeling a variable thickness sea ice cover, Mon. Weather Rev., 108, 1943–1973, https://doi.org/10.1175/1520-0493(1980)108<1943:MAVTSI>2.0.CO;2, 1980. a, b
Hunke, E. and Dukowicz, J. K.: An elastic-viscous-plastic model for sea ice dynamics, J. Phys. Oceanogr., 27, 1849–1867, https://doi.org/10.1175/1520-0485(1997)027<1849:AEVPMF>2.0.CO;2, 1997. a, b, c
Hunke, E., Hebert, D., and Lecomte, O.: Level-ice melt ponds in the Los Alamos sea ice model, CICE, Ocean Mod., 71, 26–42, https://doi.org/10.1016/j.ocemod.2012.11.008, 2013. a
Jung, T., Gordon, N. D., Bauer, P., Bromwich, D. H., Chevallier, M., Day, J. J., Dawson, J., Doblas-Reyes, F., Fairall, C., Goessling, H. F., Holland, M., Inoue, J., Iversen, T., Klebe, S., Lemke, P., Losch, M., Makshtas, A., Mills, B., Nurmi, P., Perovich, D., Reid, P., Renfrew, I. A., Smith, G., Svensson, G., Tolstykh, M., and Yang, Q.: Advancing polar prediction capabilities on daily to seasonal time scales, B. Am. Meteorol. Soc., 97, 1631–1647, https://doi.org/10.1175/BAMS-D-14-00246.1, 2016. a
Kacimi, S. and Kwok, R.: Arctic snow depth, ice thickness, and volume from ICESat-2 and CryoSat-2: 2018–2021, Geophys. Res. Lett., 49, e2021GL097448, https://doi.org/10.1029/2021GL097448, 2022. a
Kwok, R.: Arctic sea ice thickness, volume, and multiyear ice coverage: losses and coupled variability (1958–2018), Environ. Res. Lett., 13, 105005, https://doi.org/10.1088/1748-9326/aae3ec, 2018. a
Lambert, E., Nummelin, A., Pemberton, P., and Ilıcak, M.: Tracing the imprint of river runoff variability on Arctic water mass transformation., J. Geophys. Res.-Oceans, 124, 302–319, https://doi.org/10.1029/2017JC013704, 2019. a
Lavergne, T., Sørensen, A. M., Kern, S., Tonboe, R., Notz, D., Aaboe, S., Bell, L., Dybkjær, G., Eastwood, S., Gabarro, C., Heygster, G., Killie, M. A., Brandt Kreiner, M., Lavelle, J., Saldo, R., Sandven, S., and Pedersen, L. T.: Version 2 of the EUMETSAT OSI SAF and ESA CCI sea-ice concentration climate data records, The Cryosphere, 13, 49–78, https://doi.org/10.5194/tc-13-49-2019, 2019. a
Laxon, S., Giles, K. A., Ridout, A. L., Wingham, D. J., Willatt, R., Cullen, R., Kwok, R., Schweiger, A., Zhang, J., Haas, C., Hendricks, S., Krishfield, R., Kurtz, N., Farrelland, S., and Davidson, M.: CryoSat-2 estimates of Arctic sea ice thickness and volume, Geophys. Res. Lett., 40, 732–737, https://doi.org/10.1002/grl.50193, 2013. a
Lellouche, J.-M., Le Galloudec, O., Regnier, C., Van Gennip, S., Law Chune, S., Levier, B., Greiner, E., Drevillon, M., and Szczypta, C.: Quality Information Document for Global Sea Physical Analysis and Forecasting Product GLOBAL_ANALY-SISFORECAST_PHY_001_024, 1.0, Copernicus Marine Service, https://oceanrep.geomar.de/id/eprint/46419/1/CMEMS-GLO-QUID-001-024.pdf (last access: May 2022), 2016. a, b, c
Lindsay, R. W. and Zhang, J.: Assimilation of ice concentration in an ice–ocean model., J. Atmos. Ocean. Tech., 23, 742–749, https://doi.org/10.1175/jtech1871.1, 2006. a, b, c, d
Lindström, G., Pers, C., J., R., Strömqvist, J., and Arheimer, B.: Development and testing of the HYPE (Hydrological Predictions for the Environment) water quality model for different spatial scales, Hydrol. Res., 41, 295–319, https://doi.org/10.2166/nh.2010.007, 2010. a
Lipscomb, W. and Hunke, E.: Modeling sea ice transport using incremental remapping, Mon. Weather Rev., 132, 1341–1354, https://doi.org/10.1175/1520-0493(2004)132<1341:MSITUI>2.0.CO;2, 2004. a
Lipscomb, W., Hunke, E., Maslowski, W., and Jakacki, J.: Improving ridging schemes for high-resolution sea ice models, J. Geophy. Res.-Ocean, 112, C03S91, https://doi.org/10.1029/2005JC003355, 2007. a
Lisæter, K. A., Rosanova, J., and Evensen, G.: Assimilation of ice concentration in a coupled ice–ocean model using the Ensemble Kalman filter, Ocean Dynam., 53, 368–388, https://doi.org/10.1007/s10236-003-0049-4, 2003. a, b
Lorenc, A. C.: Analysis methods for numerical weather prediction, Quat. J. Roy. Meteor. Soc., 112, 1177–1194, https://doi.org/10.1002/qj.49711247414, 1986. a
Lyard, F. H., Allain, D. J., Cancet, M., Carrère, L., and Picot, N.: FES2014 global ocean tide atlas: design and performance, Ocean Sci., 17, 615–649, https://doi.org/10.5194/os-17-615-2021, 2021. a
Madec, G. and Imbard, M.: A global ocean mesh to overcome the North singularity, Clim. Dynam., 12, 381–388, https://doi.org/10.1007/BF00211684, 1996. a
Madec, G. and the NEMO Team: NEMO ocean engine, Version v3.6, Institut Peirre-Simon Laplace (IPSL), Paris, France, Zenodo, https://doi.org/10.5281/zenodo.1472492, 2017. a
Mathiot, P., König Beatty, C., Fichefet, T., Goosse, H., Massonnet, F., and Vancoppenolle, M.: Better constraints on the sea-ice state using global sea-ice data assimilation, Geosci. Model Dev., 5, 1501–1515, https://doi.org/10.5194/gmd-5-1501-2012, 2012. a, b
Maykut, G. A. and Perovich, D. K.: The role of shortwave radiation in the summer decay of a sea ice cover, J. Geophy. Res., 92, 7032–7044, https://doi.org/10.1029/JC092iC07p07032, 1987. a
Meier, W., Hovelsrud, G., van Oort, B., Key, J., Kovacs, K., Michel, C., Haas, C., Granskog, M., Gerland, S., Perovich, D., Makshtas, A., and Reist, J. D.: Arctic sea ice in transformation: A review of recent observed changes and impacts on biology and human activity, Rev. Geophy., 51, 185–217, https://doi.org/10.1002/2013RG000431, 2014. a, b
Melsheimer, C.: ASI Version 5 Sea Ice Concentration User Guide, Version V0.92, Unversity of Bremen, https://seaice.uni-bremen.de/fileadmin/user_upload/ASIuserguide.pdf (last access: January 2022), 2019. a
Melsheimer, C. and Spreen, G.: AMSR2 ASI sea ice concentration data, Arctic, version 5.4, grid resolution: 3.125 km (July 2012–today), https://seaice.uni-bremen.de/data/amsr2/, last access: June 2022. a
OSI SAF: Global Sea Ice Concentration (SSMIS), OSI-401-d, EUMETSAT Ocean and Sea Ice Satellite Application Facility, https://doi.org/10.15770/EUM_SAF_OSI_NRT_2004, 2017. a
Ozsoy-Cicek, B., Xie, H., Ackley, S. F., and Ye, K.: Antarctic summer sea ice concentration and extent: comparison of ODEN 2006 ship observations, satellite passive microwave and NIC sea ice charts, The Cryosphere, 3, 1–9, https://doi.org/10.5194/tc-3-1-2009, 2009. a, b, c, d
PAME: Arctic shipping Status Report (ASSR) #1: The Increase in Arctic Shipping 2013-2019, Arctic Council, https://pame.is/projects/arctic-marine-shipping/arctic-shipping-status-reports (last access: May 2022), 2020. a
Posey, P. G., Metzger, E. J., Wallcraft, A. J., Hebert, D. A., Allard, R. A., Smedstad, O. M., Phelps, M. W., Fetterer, F., Stewart, J. S., Meier, W. N., and Helfrich, S. R.: Improving Arctic sea ice edge forecasts by assimilating high horizontal resolution sea ice concentration data into the US Navy's ice forecast systems, The Cryosphere, 9, 1735–1745, https://doi.org/10.5194/tc-9-1735-2015, 2015. a, b, c
Rampal, P., Dansereau, V., Olason, E., Bouillon, S., Williams, T., Korosov, A., and Samaké, A.: On the multi-fractal scaling properties of sea ice deformation, The Cryosphere, 13, 2457–2474, https://doi.org/10.5194/tc-13-2457-2019, 2019. a
Ricker, R., Hendricks, S., Kaleschke, L., Tian-Kunze, X., King, J., and Haas, C.: A weekly Arctic sea-ice thickness data record from merged CryoSat-2 and SMOS satellite data, The Cryosphere, 11, 1607–1623, https://doi.org/10.5194/tc-11-1607-2017, 2017. a, b, c
Rothrock, D.: The energetics of the plastic deformation of pack ice by ridging, J. Geophys. Res.-Oceans, 80, 4514–4519, https://doi.org/10.1029/JC080i033p04514, 1975. a, b
Rousset, C., Vancoppenolle, M., Madec, G., Fichefet, T., Flavoni, S., Barthélemy, A., Benshila, R., Chanut, J., Levy, C., Masson, S., and Vivier, F.: The Louvain-La-Neuve sea ice model LIM3.6: global and regional capabilities, Geosci. Model Dev., 8, 2991–3005, https://doi.org/10.5194/gmd-8-2991-2015, 2015. a
Sakov, P., Counillon, F., Bertino, L., Lisæter, K. A., Oke, P. R., and Korablev, A.: TOPAZ4: an ocean-sea ice data assimilation system for the North Atlantic and Arctic, Ocean Sci., 8, 633–656, https://doi.org/10.5194/os-8-633-2012, 2012. a, b
Smith, D. M.: Extraction of winter total sea-ice concentration in the Greenland and Barents Seas from SSM/I data, Int. J. Remote Sens., 17, 2625–2646, https://doi.org/10.1080/01431169608949096, 1996. a
Smith, L. C. and Stepheson, S. R.: New Trans-Arctic shipping routes navigable by midcentury, P. Natl. Acad. Sci. USA, 110, E1191–E1195, https://doi.org/10.1073/pnas.1214212110, 2013. a
Stark, J. D., Ridley, J., Martin, M., and Hines, A.: Sea ice concentration and motion assimilation in a sea ice–oceanmodel, J. Geophys. Res.-Oceans, 113, C05S91, https://doi.org/10.1029/2007JC004224, 2008. a
Stauffer, D. R. and Seaman, N. L.: Use of four dimensional data assimilation in a limited area mesoscale model – Part 1: Experiments with synoptic-scale data, Mon. Weather Rev., 118, 1250–1277, https://doi.org/10.1175/1520-0493(1990)118<1250:UOFDDA>2.0.CO;2, 1990. a
Stroeve, J. and Notz, D.: Changing state of Arctic sea ice across all season, Environ. Res. Lett., 13, 103001, https://doi.org/10.1088/1748-9326/aade56, 2018. a
Sumata, H., de Steur, L., Divine, D. V., Granskog, M. A., and Gerland, S.: Regime shift in Arctic Ocean sea ice thickness, Nature, 615, 443–449, https://doi.org/10.1038/s41586-022-05686-x, 2023. a
Thorndike, A., Rothrock, D., Maykut, G., and Colony, R.: The thickness distribution of sea ice, J. Geophys. Res., 80, 4501–4513, https://doi.org/10.1029/JC080i033p04501, 1975. a, b
Tian-Kunze, X., Kaleschke, L., Maaß, N., Mäkynen, M., Serra, N., Drusch, M., and Krumpen, T.: SMOS-derived thin sea ice thickness: algorithm baseline, product specifications and initial verification, The Cryosphere, 8, 997–1018, https://doi.org/10.5194/tc-8-997-2014, 2014. a, b
Tietsche, S., Notz, D., Jungclaus, J. H., and Marotzke, J.: Assimilation of sea-ice concentration in a global climate model – physical and statistical aspects, Ocean Sci., 9, 19–36, https://doi.org/10.5194/os-9-19-2013, 2013. a, b
Tonboe, R., J., L., Pfeiffer, R., and Howe, E.: Ocean and Sea Ice SAF Product User Manual for OSI SAF Global Sea Ice Concentration Product OSI-401-b, EUMATSAT OSI SAF, https://osisaf-hl.met.no/sites/osisaf-hl.met.no/files/user_manuals/osisaf_cdop3_ss2_pum_ice-conc_v1p6.pdf (last access: November 2022), 2017. a, b
Turner, A. K., Hunke, E. C., and Bitz, C. M.: Two modes of sea-ice gravity drainage: A parameterization for large-scale modeling, J. Geophys. Res.-Oceans, 118, 2279–2294, https://doi.org/10.1002/jgrc.20171, 2013. a
Vidard, P., Le Dimet, F.-X., and Piacentini, A.: Determination of optimal nudging coefficients, Tellus A, 55, 1–15, https://doi.org/10.3402/tellusa.v55i1.14576, 2003. a
Wang, K. and Ali, A.: keguangw/hycom-cice_coin: LAON assimilation of SIC (v0.1), Zenodo [code], https://doi.org/10.5281/zenodo.7572286, 2023. a
Wang, K., Ali, A., and Wang, C.: SIC, SIT, SST and SSS from HYCOM-CICE with LAON assimilation of SIC, Zenodo [data set], https://doi.org/10.5281/zenodo.7533372, 2023a. a
Wang, K., Ali, A., and Wang, C.: SIC, SIT, SST and SSS from HYCOM-CICE with LAON assimilation of SIC (Version V2), Zenodo [data set], https://doi.org/10.5281/zenodo.10025338, 2023b. a, b
Waters, J., Lea, D., Martin, M., Mirouze, I., Weaver, A., and While, J.: Implementing a variational data assimilation system in an operational 1/4 degree global ocean model, Quart. J. Roy. Meteorol. Soc., 141, 333–349, https://doi.org/10.1002/qj.2388, 2015. a
Welch, B. L.: The generalization of Student’s problem when several different population variances are involved, Biometrika., 34, 28–35, https://doi.org/10.1093/biomet/34.1-2.28, 1947. a
While, J. and Martin, M.: Development of a variational data assimilation system for the diurnal cycle of sea surface temperature, J. Geophys. Res.-Oceans, 118, 2845–2862, https://doi.org/10.1002/jgrc.20215, 2013. a
Yang, Q., Losa, S. N., Losch, M., Tian-Kunze, X., Nerger, L., Liu, J., Kaleschke, L., and Zhang, Z.: Assimilating SMOS sea ice thickness into a coupled ice-ocean model using a local SEIK filter, J. Geophys. Res.-Oceans, 119, 6680–6692, https://doi.org/10.1002/2014JC009963, 2014. a
Zhang, J., Thomas, D., and Rothrock, D.: Assimilation of ice motion observations and comparisons with submarine ice thickness data, J. Geophys. Res.-Oceans, 108, 3170, https://doi.org/10.1029/2001jc001041, 2003. a
Zou, X., Navon, I. M., and Ledimet, F. X.: An Optimal Nudging Data Assimilation Scheme Using Parameter Estimation, Q. J. Roy. Meteor. Soc., 118, 1163–1186, https://doi.org/10.1002/qj.49711850808, 1992. a
Short summary
A simple, efficient. and accurate data assimilation method, local analytical optimal nudging (LAON), is introduced to assimilate high-resolution sea ice concentration in a pan-Arctic high-resolution coupled ocean and sea ice model. The method provides a new vision by nudging the model evolution to the optimal estimate forwardly, continuously, and smoothly. This method is applicable to the general nudging theory and applications in physics, Earth science, psychology, and behavior sciences.
A simple, efficient. and accurate data assimilation method, local analytical optimal nudging...