Articles | Volume 21, issue 4
https://doi.org/10.5194/os-21-1205-2025
© 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-21-1205-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
02 Jul 2025
Research article |
| 02 Jul 2025
| 02 Jul 2025
Simulated density reorganization on the Weddell Sea continental shelf sensitive to atmospheric forcing
Department of Biogeochemical Modelling, GEOMAR, 24148 Kiel, Germany
Alfred Wegener Institute for Polar and Marine Research, 27570 Bremerhaven, Germany
Ralph Timmermann
Department of Biogeochemical Modelling, GEOMAR, 24148 Kiel, Germany
Cara Nissen
Department of Atmospheric and Oceanic Sciences and Institute of Arctic and Alpine Research, University of Colorado, Boulder, Boulder, Colorado, USA
Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, Netherlands
Rolf Zentek
Department of Environmental Meteorology, University of Trier, 54286 Trier, Germany
German Weather Service, 63067 Offenbach, Germany
Tido Semmler
Department of Biogeochemical Modelling, GEOMAR, 24148 Kiel, Germany
Met Éireann, 65–67 Glasnevin Hill, D09 Y921 Dublin, Ireland
Günther Heinemann
Department of Environmental Meteorology, University of Trier, 54286 Trier, Germany
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Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-182, https://doi.org/10.5194/bg-2023-182, 2023
Revised manuscript not accepted
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For assessing the consequences of human-induced climate change for the marine realm, it is necessary to not only look at gradual changes but also at abrupt changes of environmental conditions. We summarise abrupt changes in ocean warming, acidification, and oxygen concentration as the key environmental factors for ecosystems. Taking these abrupt changes into account requires greenhouse gas emissions to be reduced to a larger extent than previously thought to limit respective damage.
Sascha Willmes, Günther Heinemann, and Frank Schnaase
The Cryosphere, 17, 3291–3308, https://doi.org/10.5194/tc-17-3291-2023, https://doi.org/10.5194/tc-17-3291-2023, 2023
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Sea ice is an important constituent of the global climate system. We here use satellite data to identify regions in the Arctic where the sea ice breaks up in so-called leads (i.e., linear cracks) regularly during winter. This information is important because leads determine, e.g., how much heat is exchanged between the ocean and the atmosphere. We here provide first insights into the reasons for the observed patterns in sea-ice leads and their relation to ocean currents and winds.
Cited articles
Årthun, M., Nicholls, K.-W., Makinson, K., Fedak, M.-A., and Boehme, L.: Seasonal inflow of warm water onto the southern Weddell Sea continental shelf, Antarctica, Geophys. Res. Lett., 39, 2–7, https://doi.org/10.1029/2012GL052856, 2012. a
Beadling, R. L., Krasting, J. P., Griffies, S. M., Hurlin, W. J., Bronselaer, B., Russell, J. L., MacGilchrist, G. A., Tesdal, J., and Winton, M.: Importance of the Antarctic Slope Current in the Southern Ocean Response to Ice Sheet Melt and Wind Stress Change, J. Geophys. Res.-Oceans, 127, e2021JC017608, https://doi.org/10.1029/2021JC017608, 2022. a, b
Calvin, K., Dasgupta, D., Krinner, G., Mukherji, A., Thorne, P. W., Trisos, C., Romero, J., Aldunce, P., Barrett, K., Blanco, G., Cheung, W. W., Connors, S., Denton, F., Diongue-Niang, A., Dodman, D., Garschagen, M., Geden, O., Hayward, B., Jones, C., Jotzo, F., Krug, T., Lasco, R., Lee, Y.-Y., Masson-Delmotte, V., Meinshausen, M., Mintenbeck, K., Mokssit, A., Otto, F. E., Pathak, M., Pirani, A., Poloczanska, E., Pörtner, H.-O., Revi, A., Roberts, D. C., Roy, J., Ruane, A. C., Skea, J., Shukla, P. R., Slade, R., Slangen, A., Sokona, Y., Sörensson, A. A., Tignor, M., van Vuuren, D., Wei, Y.-M., Winkler, H., Zhai, P., Zommers, Z., Hourcade, J.-C., Johnson, F. X., Pachauri, S., Simpson, N. P., Singh, C., Thomas, A., Totin, E., Alegría, A., Armour, K., Bednar-Friedl, B., Blok, K., Cissé, G., Dentener, F., Eriksen, S., Fischer, E., Garner, G., Guivarch, C., Haasnoot, M., Hansen, G., Hauser, M., Hawkins, E., Hermans, T., Kopp, R., Leprince-Ringuet, N., Lewis, J., Ley, D., Ludden, C., Niamir, L., Nicholls, Z., Some, S., Szopa, S., Trewin, B., van der Wijst, K.-I., Winter, G., Witting, M., Birt, A., and Ha, M.: IPCC 2023: Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Core Writing Team, Lee, H., and Romero, J., IPCC, Geneva, Switzerland, Tech. rep., Intergovernmental Panel on Climate Change, https://doi.org/10.59327/IPCC/AR6-9789291691647, 2023. a
Cape, M. R., Vernet, M., Skvarca, P., Marinsek, S., Scambos, T., and Domack, E.: Foehn winds link climate-driven warming to ice shelf evolution in Antarctica, J. Geophys. Res.-Atmos., 120, 11037–11057, https://doi.org/10.1002/2015JD023465, 2015. a, b
Daae, K., Hattermann, T., Darelius, E., Mueller, R., Naughten, K. A., and Timmermann, R. e. a.: Necessary Conditions for Warm Inflow Toward the Filchner Ice Shelf, Weddell Sea, Geophys. Res. Lett., 47, e2020GL089237, https://doi.org/10.1029/2020GL089237, 2020. a, b
Danilov, S., Wang, Q., Timmermann, R., Iakovlev, N., Sidorenko, D., Kimmritz, M., Jung, T., and Schröter, J.: Finite-Element Sea Ice Model (FESIM), version 2, Geosci. Model Dev., 8, 1747–1761, https://doi.org/10.5194/gmd-8-1747-2015, 2015. a
Darelius, E., Fer, I., and Nicholls, K.-W.: Observed vulnerability of Filchner-Ronne Ice Shelf to wind-driven inflow of warm deep water, Nat. Commun., 7, 1–7, https://doi.org/10.1038/ncomms12300, 2016. a
Dettling, N., Losch, M., Pollmann, F., and Kanzow, T.: Toward Parameterizing Eddy-Mediated Transport of Warm Deep Water across the Weddell Sea Continental Slope, J. Phys. Oceanogr., 54, 1675–1690, https://doi.org/10.1175/JPO-D-23-0215.1, 2024. a
Dinniman, M., Klinck, J., Bai, L.-S., Bromwich, D., Hines, K. M., and Holland, D.: The effect of atmospheric forcing resolution on the delivery of ocean heat to the Antarctic floating ice shelves, J. Climate, 28, 6067–6085, https://doi.org/10.1175/JCLI-D-14-00374.1, 2015. a
Elvidge, A., Renfrew, I., King, J., Orr, A., and Lachlan-Cope, T.: Foehn warming distributions in non-linear and linear flow regimes: A focus on the Antarctic Peninsula, Q. J. Roy. Meteorol. Soc., 142, 618–631, https://doi.org/10.1002/qj.2489, 2014. a, b
Foldvik, A., Gammelsrø d, T., and Torresen, T.: Circulation and Water Masses on the Southern Weddell Sea Shelf, Ocean. Antarct. Cont. Shelf, 43, 5–20, 1985. a
Gent, P. R. and McWilliams, J. C.: Isopycnal mixing in ocean circulation models, J. Phys. Oceanogr., 20, 150–155, https://doi.org/10.1175/1520-0485(1990)020<0150:IMIOCM>2.0.CO;2, 1990. a
Gierz, P., Andrés-Martínez, M., Barbi, D., Wieters, N., Cristini, L., Streffing, J., Wahl, S., Ural, D., Kjellsson, J., Chegini, F., and Khosravi, S.: ESM-Tools, Zenodo [software], https://doi.org/10.5281/zenodo.5787476, 2021. a
Goyal, R., Sen Gupta, A., Jucker, M., and England, M. H.: Historical and Projected Changes in the Southern Hemisphere Surface Westerlies, Geophys. Res. Lett., 48, 1–13, 2021. a
Gürses, Ö., Kolatschek, V., Wang, Q., and Rodehacke, C. B.: Brief communication: A submarine wall protecting the Amundsen Sea intensifies melting of neighboring ice shelves, The Cryosphere, 13, 2317–2324, https://doi.org/10.5194/tc-13-2317-2019, 2019. a
Haid, V., Timmermann, R., Ebner, L., and Heinemann, G.: Atmospheric forcing of coastal polynyas in the southwestern Weddell Sea, Antarct. Sci., 27, 388–402, https://doi.org/10.1017/S0954102014000893, 2015. a, b, c
Hattermann, T.: Antarctic thermocline dynamics along a narrow shelf with easterly winds, J. Phys. Oceanogr., 48, 2419–2443, https://doi.org/10.1175/JPO-D-18-0064.1, 2018. a
Hattermann, T., Nicholls, K. W., Hellmer, H. H., Davis, P. E. D., Janout, M. A., Østerhus, S., Schlosser, E., Rohardt, G., and Kanzow, T.: Observed interannual changes beneath Filchner-Ronne Ice Shelf linked to large-scale atmospheric circulation. Nat Commun, 12, 2961, https://doi.org/10.1038/s41467-021-23131-x, 2021. a
Heinemann, G., Schefczyk, L., Willmes, S., and Shupe, M. D.: Evaluation of simulations of near-surface variables using the regional climate model CCLM for the MOSAiC winter period, Elementa: Sci. Anthrop., 10, 1–22, 2022. a
Hellmer, H. H. and Olbers, D. J.: A two-dimensional model for the thermohaline circulation under an ice shelf, Antarct. Sci., 1, 325–336, https://doi.org/10.1017/S0954102089000490, 1989. a
Hellmer, H. H., Kauker, F., Timmermann, R., Determann, J., and Rae, J.: Twenty-first-century warming of a large Antarctic ice-shelf cavity by a redirected coastal current, Nature, 485, 225–228, https://doi.org/10.1038/nature11064, 2012. a
Hellmer, H. H., Kauker, F., Timmermann, R., and Hattermann, T.: The fate of the Southern Weddell sea continental shelf in a warming climate, J. Climate, 30,, 4337–4350, https://doi.org/10.1175/JCLI-D-16-0420.1, 2017. a, b
Heywood, K. J., Schmidtko, S., Heuzé, C., Kaiser, J., Jickells, T. D., Queste, B. Y., Stevens, D. P., Wadley, M., Thompson, A. F., Fielding, S., Guihen, D., Creed, E., Ridley, J. K., and Smith, W.: Ocean processes at the Antarctic continental slope, Philos. T. Roy. Soc. A, 372, 20130047, https://doi.org/10.1098/rsta.2013.0047, 2014. a
Holland, D. M. and Jenkins, A.: Modeling Thermodynamic Ice–Ocean Interactions at the Base of an Ice Shelf, J. Phys. Oceanogr., 29, 1787–1800, https://doi.org/10.1175/1520-0485(1999)029<1787:MTIOIA>2.0.CO;2, 1999. a
Huneke, W. G. C., Morrison, A. K., and Hogg, A. M.: Spatial and Subannual Variability of the Antarctic Slope Current in an Eddying Ocean–Sea Ice Model, J. Phys. Oceanogr., 52, 347–361, 2022. a
Janout, M. A., Hellmer, H. H., Schröder, M., and Wisotzki, A.: Physical oceanography during POLARSTERN cruise PS111 (ANT-XXXIII/2), Pangaea, https://doi.org/10.1594/PANGAEA.897280, 2019. a
Large, W. and Yeager, S.: Diurnal to decadal global forcing for ocean and seaice models: the data sets and climatologies, (No. NCAR/TN-460+ STR), University Corporation for Atmospheric Research: NCAR, 2044, 2004. a
Lockwood, J. W., Dufour, C. O., Griffies, S. M., and Winton, M.: On the Role of the Antarctic Slope Front on the Occurrence of the Weddell Sea Polynya under Climate Change, J. Climate, 34, 2529–2548, 2021. a
Mathiot, P., Goosse, H., Fichefet, T., Barnier, B., and Gallée, H.: Modelling the seasonal variability of the Antarctic Slope Current, Ocean Sci., 7, 455–470, https://doi.org/10.5194/os-7-455-2011, 2011. a, b, c, d
Meinshausen, M., Nicholls, Z. R. J., Lewis, J., Gidden, M. J., Vogel, E., Freund, M., Beyerle, U., Gessner, C., Nauels, A., Bauer, N., Canadell, J. G., Daniel, J. S., John, A., Krummel, P. B., Luderer, G., Meinshausen, N., Montzka, S. A., Rayner, P. J., Reimann, S., Smith, S. J., van den Berg, M., Velders, G. J. M., Vollmer, M. K., and Wang, R. H. J.: The shared socio-economic pathway (SSP) greenhouse gas concentrations and their extensions to 2500, Geosci. Model Dev., 13, 3571–3605, https://doi.org/10.5194/gmd-13-3571-2020, 2020. a
Naughten, K. A., De Rydt, J., Rosier, S. H. R., Jenkins, A., Holland, P. R., and Ridley, J. K.: Two-timescale response of a large Antarctic ice shelf to climate change, Nat. Commun., 12, 1–10, https://doi.org/10.1038/s41467-021-22259-0, 2021. a, b, c, d
Nissen, C., Timmermann, R., Hoppema, M., Gürses, Ö., and Hauck, J.: Abruptly attenuated carbon sequestration with Weddell Sea dense waters by 2100, Nat. Commun., 13, 3402, https://doi.org/10.1038/s41467-022-30671-3, 2022. a, b
Nissen, C., Timmermann, R., van Caspel, M., and Wekerle, C.: Altered Weddell Sea warm- and dense-water pathways in response to 21st-century climate change, Ocean Sci., 20, 85–101, https://doi.org/10.5194/os-20-85-2024, 2024. a
Nøst, O., Biuw, M., Tverberg, V., Lydersen, C., Hattermann, T., Zhou, Q., Smedsrud, L. H., , and Kovacs, K. M.: Eddy overturning of the Antarctic Slope Front controls glacial melting in the Eastern Weddell Sea, J. Geophys. Res., 116, 1–17, https://doi.org/10.1029/2011JC006965, 2011. a, b, c, d
Ong, E. Q. Y., Doddridge, E., Constantinou, N. C., Hogg, A. M., and England, M. H.: Intrinsically Episodic Antarctic Shelf Intrusions of Circumpolar Deep Water via Canyons, J. Phys. Oceanogr., 54, 1195–1210, 2023. a
Ou, H.: Watermass Properties of the Antarctic Slope Front: A Simple Model, J. Phys. Oceanogr., 37, 50–59, 2007. a
Powers, J. G., Manning, K. W., Bromwich, D. H., Cassano, J. J., and Cayette, A. M.: A Decade of Antarctic Science Support Through Amps, B. Am. Meteorol. Soc., 93, 1699–1712, https://doi.org/10.1175/bams-d-11-00186.1, 2012. a
Redi, M. H.: Oceanic Isopycnal Mixing by Coordinate Rotation, J. Phys. Oceanogr., 12, 1154–1158, https://doi.org/10.1175/1520-0485(1982)012<1154:OIMBCR>2.0.CO;2, 1982. a
Ryan, S., Hattermann, T., Darelius, E., and Schröder, M.: Seasonal cycle of hydrography on the eastern shelf of the Filchner Trough, Weddell Sea, Antarctica, J. Geophys. Res.-Oceans, 122, 6437–6453, https://doi.org/10.1002/2017JC012916, 2017. a, b, c
Ryan, S., Hellmer, H. H., Janout, M., Darelius, E., Vignes, L., and Schröder, M.: Exceptionally Warm and Prolonged Flow of Warm Deep Water Toward the Filchner-Ronne Ice Shelf in 2017, Geophys. Res. Lett., 47, 1–10, https://doi.org/10.1029/2020GL088119, 2020. a, b, c, d
Schaffer, J., Timmermann, R., Arndt, J. E., Kristensen, S. S., Mayer, C., Morlighem, M., and Steinhage, D.: A global, high-resolution data set of ice sheet topography, cavity geometry, and ocean bathymetry, Earth Syst. Sci. Data, 8, 543–557, https://doi.org/10.5194/essd-8-543-2016, 2016. a
Schmidtko, S., Heywood, K. J., Thompson, A. F., , and Aoki, S.: Multidecadal warming of Antarctic waters, Science, 346, 1227–1232, https://doi.org/10.1126/science.1256117, 2014. a
Schröder, M.: Physical oceanography during POLARSTERN cruise ANT-XII/3, Pangaea, https://doi.org/10.1594/PANGAEA.742581, 2010. a
Schröder, M. and Wisotzki, A.: Physical oceanography during POLARSTERN cruise PS82 (ANT-XXIX/9), Pangaea, https://doi.org/10.1594/PANGAEA.833299, 2014. a
Schröder, M., Ryan, S., and Wisotzki, A.: Physical oceanography during POLARSTERN cruise PS96 (ANT-XXXI/2 FROSN), Pangaea, https://doi.org/10.1594/PANGAEA.859040, 2016. a
Schröder, M., Ryan, S., and Wisotzki, A.: Physical oceanography and current meter data from mooring AWI254-2, Pangaea, https://doi.org/10.1594/PANGAEA.903317, 2019. a
Semmler, T., Danilov, S., Gierz, P., Goessling, H. F., Hegewald, J., and Hinrichs, C. E. A.: Simulations for CMIP6 With the AWI Climate Model AWI-CM-1-1, J. Adv. Model. Earth Syst., 12, 1–34, https://doi.org/10.1029/2019MS002009, 2020. a
St-Laurent, P., Klinck, J. M., and Dinniman, M. S.: On the role of coastal troughs in the circulation of warm circumpolar deep water on Antarctic shelves, J. Phys. Oceanogr., 43, 51–64, 2013. a
Steger, C. and Bucchignani, E.: Regional Climate Modelling with COSMO-CLM: History and Perspectives, Atmosphere, 11, https://doi.org/10.3390/atmos11111250, 2020. a
Stewart, A., Klocker, A., and Menemenlis, D.: Acceleration and Overturning of the Antarctic Slope Current by Winds, Eddies, and Tides, J. Phys. Oceanogr., 49, 2043–2074, 2019. a
Stössel, A., Zhang, Z., and Vihma, T.: The effect of alternative real‐time wind forcing on Southern Ocean sea ice simulations, J. Geophys. Res.-Oceans, 116, 1–19, https://doi.org/10.1029/2011JC007328, 2011. a
Sverdrup, H.: The Currents off the Coast of Queen Maud Land, Norsk Geograf. Tidssk., 14, 239–249, https://doi.org/10.1080/00291955308542731, 1954. a
Teske, V., Timmermann, R., and Semmler, T.: FESOM1.4 model data used in the paper “Simulated density reorganization on the Weddell Sea continental shelf sensitive to atmospheric forcing, Zenodo [data set], https://doi.org/10.5281/zenodo.15120056, 2025. a
The COSMO consortium: Consortium for small scale modeling COSMO, https://www.cosmo-model.org/content/consortium/licencing.htm (last access: 7 August 2021), 2021. a
Timmermann, R. and Goeller, S.: Response to Filchner–Ronne Ice Shelf cavity warming in a coupled ocean–ice sheet model – Part 1: The ocean perspective, Ocean Sci., 13, 765–776, https://doi.org/10.5194/os-13-765-2017, 2017. a
Timmermann, R., Wang, Q., and Hellmer, H.: Ice-shelf basal melting in a global finite-element sea-ice/ice-shelf/ocean model, Ann. Glaciol., 53, 303–314, 2012. a
Turner, J., Phillips, T., Hosking, J. S., Marshall, G. J., and Orr, A.: The Amundsen Sea Low, Int. J. Climatol., 13, 1818–1829, https://doi.org/10.1002/joc.3558, 2013. a
Van Lipzig, N. P. M., King, J. C., Lachlan-Cope, T. A., and van den Broeke, M. R.: Precipitation, sublimation, and snow drift in the Antarctic Peninsula region from a regional atmospheric model, J. Geophys. Res., 109, D24106, https://doi.org/10.1029/2004JD004701, 2004. a
Van Wessem, J. M., Reijmer, C. H., van de Berg, W. J., van den Broeke, M. R., J., C. A., van Ulft, L. H. E., and van Meijgaard, E.: Temperature and Wind Climate of the Antarctic Peninsula as Simulated by a High-Resolution Regional Atmospheric Climate Model, J. Climate, 28, 1831–1844, 2015. a
Wang, Q., Danilov, S., Sidorenko, D., Timmermann, R., Wekerle, C., Wang, X., Jung, T., and Schröter, J.: The Finite Element Sea Ice-Ocean Model (FESOM) v.1.4: formulation of an ocean general circulation model, Geosci. Model Dev., 7, 663–693, https://doi.org/10.5194/gmd-7-663-2014, 2014. a, b, c
Zentek, R. and Heinemann, G.: Verification of the regional atmospheric model CCLM v5.0 with conventional data and lidar measurements in Antarctica, Geosci. Model Dev., 13, 1809–1825, https://doi.org/10.5194/gmd-13-1809-2020, 2020. a, b
Zentek, R. and Heinemann, G.: COSMO-CLM REDOCCA Simulation (Version 2), DOKU at DKRZ [data set], https://hdl.handle.net/21.14106/cb44f718061ed8e9cdeb574d51113b64ec781564 (last access: 7 August 2024), 2023. a
Short summary
We investigate the structural changes the Antarctic Slope Front in the southern Weddell Sea experiences in a warming climate by conducting two ocean simulations driven by atmospheric data of different horizontal resolutions. Cross-slope currents associated with a regime shift from a cold to a warm Filchner Trough on the continental shelf temporarily disturb the structure of the slope front and reduce its depth, but the primary reason for a regime shift is the cross-slope density gradient.
We investigate the structural changes the Antarctic Slope Front in the southern Weddell Sea...
