Articles | Volume 14, issue 8
https://doi.org/10.5194/gmd-14-4909-2021
© Author(s) 2021. 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-14-4909-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Development and technical paper
| 
06 Aug 2021
Development and technical paper |
| 06 Aug 2021
| 06 Aug 2021
Development of adjoint-based ocean state estimation for the Amundsen and Bellingshausen seas and ice shelf cavities using MITgcm–ECCO (66j)
Yoshihiro Nakayama
CORRESPONDING AUTHOR
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
Institute of Low Temperature Science, Hokkaido University, Sapporo, Hokkaido, Japan
Dimitris Menemenlis
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
Hong Zhang
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
Ian Fenty
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
An T. Nguyen
The University of Texas at Austin, Austin, Texas, USA
Related authors
Claire K. Yung, Madelaine G. Rosevear, Adele K. Morrison, Andrew McC Hogg, and Yoshihiro Nakayama
EGUsphere, https://doi.org/10.5194/egusphere-2024-3513, https://doi.org/10.5194/egusphere-2024-3513, 2024
Short summary
Short summary
Ocean models are used to understand how the ocean interacts with the Antarctic Ice Sheet, but they are too coarse in resolution to capture the small-scale ocean processes driving melting and require a parameterisation to predict melt. Previous parameterisations ignore key processes occurring in some regions of Antarctica. We develop a parameterisation with the feedback of stratification on melting and test it in idealised and regional ocean models, finding changes to melt rate and circulation.
Yoshihiro Nakayama, Alena Malyarenko, Hong Zhang, Ou Wang, Matthis Auger, Yafei Nie, Ian Fenty, Matthew Mazloff, Armin Köhl, and Dimitris Menemenlis
Geosci. Model Dev., 17, 8613–8638, https://doi.org/10.5194/gmd-17-8613-2024, https://doi.org/10.5194/gmd-17-8613-2024, 2024
Short summary
Short summary
Global- and basin-scale ocean reanalyses are becoming easily accessible. However, such ocean reanalyses are optimized for their entire model domains and their ability to simulate the Southern Ocean requires evaluation. We conduct intercomparison analyses of Massachusetts Institute of Technology General Circulation Model (MITgcm)-based ocean reanalyses. They generally perform well for the open ocean, but open-ocean temporal variability and Antarctic continental shelves require improvements.
Jan De Rydt, Nicolas C. Jourdain, Yoshihiro Nakayama, Mathias van Caspel, Ralph Timmermann, Pierre Mathiot, Xylar S. Asay-Davis, Hélène Seroussi, Pierre Dutrieux, Ben Galton-Fenzi, David Holland, and Ronja Reese
Geosci. Model Dev., 17, 7105–7139, https://doi.org/10.5194/gmd-17-7105-2024, https://doi.org/10.5194/gmd-17-7105-2024, 2024
Short summary
Short summary
Global climate models do not reliably simulate sea-level change due to ice-sheet–ocean interactions. We propose a community modelling effort to conduct a series of well-defined experiments to compare models with observations and study how models respond to a range of perturbations in climate and ice-sheet geometry. The second Marine Ice Sheet–Ocean Model Intercomparison Project will continue to lay the groundwork for including ice-sheet–ocean interactions in global-scale IPCC-class models.
Vår Dundas, Elin Darelius, Kjersti Daae, Nadine Steiger, Yoshihiro Nakayama, and Tae-Wan Kim
Ocean Sci., 18, 1339–1359, https://doi.org/10.5194/os-18-1339-2022, https://doi.org/10.5194/os-18-1339-2022, 2022
Short summary
Short summary
Ice shelves in the Amundsen Sea are thinning rapidly as ocean currents bring warm water into cavities beneath the floating ice. We use 2-year-long mooring records and 16-year-long model simulations to describe the hydrography and circulation near the ice front between Siple and Carney Islands. We find that temperatures here are lower than at neighboring ice fronts and that the transport of heat toward the cavity is governed by wind stress over the Amundsen Sea continental shelf.
Xue Feng, Matthew J. Widlansky, Tong Lee, Ou Wang, Magdalena A. Balmaseda, Hao Zuo, Gregory Dusek, William Sweet, and Malte F. Stuecker
Ocean Sci., 21, 1663–1676, https://doi.org/10.5194/os-21-1663-2025, https://doi.org/10.5194/os-21-1663-2025, 2025
Short summary
Short summary
Forecasting sea level changes months in advance along the Gulf Coast and East Coast of the United States is challenging. Here, we present a method that uses past ocean states to forecast future sea levels, while assuming no knowledge of how the atmosphere will evolve other than its typical annual cycle near the ocean's surface. Our findings indicate that this method improves sea level outlooks for many locations along the Gulf Coast and East Coast, especially south of Cape Hatteras.
Raphaël Savelli, Dustin Carroll, Dimitris Menemenlis, Jonathan Lauderdale, Clément Bertin, Stephanie Dutkiewicz, Manfredi Manizza, Anthony Bloom, Karel Castro-Morales, Charles E. Miller, Marc Simard, Kevin W. Bowman, and Hong Zhang
EGUsphere, https://doi.org/10.5194/egusphere-2025-1707, https://doi.org/10.5194/egusphere-2025-1707, 2025
This preprint is open for discussion and under review for Geoscientific Model Development (GMD).
Short summary
Short summary
Accounting for carbon and nutrients in rivers is essential for resolving carbon dioxide (CO2) exchanges between the ocean and the atmosphere. In this study, we add the effect of present-day rivers to a pioneering global-ocean biogeochemistry model. This study highlights the challenge for global ocean numerical models to cover the complexity of the flow of water and carbon across the Land-to-Ocean Aquatic Continuum.
Claire K. Yung, Madelaine G. Rosevear, Adele K. Morrison, Andrew McC Hogg, and Yoshihiro Nakayama
EGUsphere, https://doi.org/10.5194/egusphere-2024-3513, https://doi.org/10.5194/egusphere-2024-3513, 2024
Short summary
Short summary
Ocean models are used to understand how the ocean interacts with the Antarctic Ice Sheet, but they are too coarse in resolution to capture the small-scale ocean processes driving melting and require a parameterisation to predict melt. Previous parameterisations ignore key processes occurring in some regions of Antarctica. We develop a parameterisation with the feedback of stratification on melting and test it in idealised and regional ocean models, finding changes to melt rate and circulation.
Yoshihiro Nakayama, Alena Malyarenko, Hong Zhang, Ou Wang, Matthis Auger, Yafei Nie, Ian Fenty, Matthew Mazloff, Armin Köhl, and Dimitris Menemenlis
Geosci. Model Dev., 17, 8613–8638, https://doi.org/10.5194/gmd-17-8613-2024, https://doi.org/10.5194/gmd-17-8613-2024, 2024
Short summary
Short summary
Global- and basin-scale ocean reanalyses are becoming easily accessible. However, such ocean reanalyses are optimized for their entire model domains and their ability to simulate the Southern Ocean requires evaluation. We conduct intercomparison analyses of Massachusetts Institute of Technology General Circulation Model (MITgcm)-based ocean reanalyses. They generally perform well for the open ocean, but open-ocean temporal variability and Antarctic continental shelves require improvements.
Jan De Rydt, Nicolas C. Jourdain, Yoshihiro Nakayama, Mathias van Caspel, Ralph Timmermann, Pierre Mathiot, Xylar S. Asay-Davis, Hélène Seroussi, Pierre Dutrieux, Ben Galton-Fenzi, David Holland, and Ronja Reese
Geosci. Model Dev., 17, 7105–7139, https://doi.org/10.5194/gmd-17-7105-2024, https://doi.org/10.5194/gmd-17-7105-2024, 2024
Short summary
Short summary
Global climate models do not reliably simulate sea-level change due to ice-sheet–ocean interactions. We propose a community modelling effort to conduct a series of well-defined experiments to compare models with observations and study how models respond to a range of perturbations in climate and ice-sheet geometry. The second Marine Ice Sheet–Ocean Model Intercomparison Project will continue to lay the groundwork for including ice-sheet–ocean interactions in global-scale IPCC-class models.
Hector S. Torres, Patrice Klein, Jinbo Wang, Alexander Wineteer, Bo Qiu, Andrew F. Thompson, Lionel Renault, Ernesto Rodriguez, Dimitris Menemenlis, Andrea Molod, Christopher N. Hill, Ehud Strobach, Hong Zhang, Mar Flexas, and Dragana Perkovic-Martin
Geosci. Model Dev., 15, 8041–8058, https://doi.org/10.5194/gmd-15-8041-2022, https://doi.org/10.5194/gmd-15-8041-2022, 2022
Short summary
Short summary
Wind work at the air-sea interface is the scalar product of winds and currents and is the transfer of kinetic energy between the ocean and the atmosphere. Using a new global coupled ocean-atmosphere simulation performed at kilometer resolution, we show that all scales of winds and currents impact the ocean dynamics at spatial and temporal scales. The consequential interplay of surface winds and currents in the numerical simulation motivates the need for a winds and currents satellite mission.
Vår Dundas, Elin Darelius, Kjersti Daae, Nadine Steiger, Yoshihiro Nakayama, and Tae-Wan Kim
Ocean Sci., 18, 1339–1359, https://doi.org/10.5194/os-18-1339-2022, https://doi.org/10.5194/os-18-1339-2022, 2022
Short summary
Short summary
Ice shelves in the Amundsen Sea are thinning rapidly as ocean currents bring warm water into cavities beneath the floating ice. We use 2-year-long mooring records and 16-year-long model simulations to describe the hydrography and circulation near the ice front between Siple and Carney Islands. We find that temperatures here are lower than at neighboring ice fronts and that the transport of heat toward the cavity is governed by wind stress over the Amundsen Sea continental shelf.
Takaya Uchida, Julien Le Sommer, Charles Stern, Ryan P. Abernathey, Chris Holdgraf, Aurélie Albert, Laurent Brodeau, Eric P. Chassignet, Xiaobiao Xu, Jonathan Gula, Guillaume Roullet, Nikolay Koldunov, Sergey Danilov, Qiang Wang, Dimitris Menemenlis, Clément Bricaud, Brian K. Arbic, Jay F. Shriver, Fangli Qiao, Bin Xiao, Arne Biastoch, René Schubert, Baylor Fox-Kemper, William K. Dewar, and Alan Wallcraft
Geosci. Model Dev., 15, 5829–5856, https://doi.org/10.5194/gmd-15-5829-2022, https://doi.org/10.5194/gmd-15-5829-2022, 2022
Short summary
Short summary
Ocean and climate scientists have used numerical simulations as a tool to examine the ocean and climate system since the 1970s. Since then, owing to the continuous increase in computational power and advances in numerical methods, we have been able to simulate increasing complex phenomena. However, the fidelity of the simulations in representing the phenomena remains a core issue in the ocean science community. Here we propose a cloud-based framework to inter-compare and assess such simulations.
Ehud Strobach, Andrea Molod, Donifan Barahona, Atanas Trayanov, Dimitris Menemenlis, and Gael Forget
Geosci. Model Dev., 15, 2309–2324, https://doi.org/10.5194/gmd-15-2309-2022, https://doi.org/10.5194/gmd-15-2309-2022, 2022
Short summary
Short summary
The Green's functions methodology offers a systematic, easy-to-implement, computationally cheap, scalable, and extendable method to tune uncertain parameters in models accounting for the dependent response of the model to a change in various parameters. Herein, we successfully show for the first time that long-term errors in earth system models can be considerably reduced using Green's functions methodology. The method can be easily applied to any model containing uncertain parameters.
Marion Kersalé, Denis L. Volkov, Kandaga Pujiana, and Hong Zhang
Ocean Sci., 18, 193–212, https://doi.org/10.5194/os-18-193-2022, https://doi.org/10.5194/os-18-193-2022, 2022
Short summary
Short summary
The southern Indian Ocean is one of the major basins for regional heat accumulation and sea level rise. The year-to-year changes of regional sea level are influenced by water exchange with the Pacific Ocean via the Indonesian Throughflow. Using a general circulation model, we show that the spatiotemporal pattern of these changes is primarily set by local wind forcing modulated by El Niño–Southern Oscillation, while oceanic signals originating in the Pacific can amplify locally forced signals.
Amy Solomon, Céline Heuzé, Benjamin Rabe, Sheldon Bacon, Laurent Bertino, Patrick Heimbach, Jun Inoue, Doroteaciro Iovino, Ruth Mottram, Xiangdong Zhang, Yevgeny Aksenov, Ronan McAdam, An Nguyen, Roshin P. Raj, and Han Tang
Ocean Sci., 17, 1081–1102, https://doi.org/10.5194/os-17-1081-2021, https://doi.org/10.5194/os-17-1081-2021, 2021
Short summary
Short summary
Freshwater in the Arctic Ocean plays a critical role in the global climate system by impacting ocean circulations, stratification, mixing, and emergent regimes. In this review paper we assess how Arctic Ocean freshwater changed in the 2010s relative to the 2000s. Estimates from observations and reanalyses show a qualitative stabilization in the 2010s due to a compensation between a freshening of the Beaufort Gyre and a reduction in freshwater in the Amerasian and Eurasian basins.
Yang Feng, Dimitris Menemenlis, Huijie Xue, Hong Zhang, Dustin Carroll, Yan Du, and Hui Wu
Geosci. Model Dev., 14, 1801–1819, https://doi.org/10.5194/gmd-14-1801-2021, https://doi.org/10.5194/gmd-14-1801-2021, 2021
Short summary
Short summary
Simulation of coastal plume regions was improved in global ECCOv4 with a series of sensitivity tests. We find modeled SSS is closer to SMAP when using daily point-source runoff as well as increasing the resolution from coarse to intermediate. The plume characteristics, freshwater transport, and critical water properties are modified greatly. But this may not happen with a further increase to high resolution. The study will advance the seamless modeling of land–ocean–atmosphere feedback in ESMs.
Cited articles
Arndt, J. E., H. W., Schenke, M., Jakobsson, F., Nitsche, G., Buys, B., Goleby, M., Rebesco, F., Bohoyo, J. K., Hong, J., Black, R., Greku, G., Udintsev, F., Barrios, W., Reynoso-Peralta, T., Morishita, R., and Wigley, R.: The International Bathymetric Chart of the Southern Ocean (IBCSO) Version 1.0 A new
bathymetric compilation covering circum-Antarctic waters, Geophys. Res. Lett., 40, 3111–3117, 2013. a
Arrigo, K. R., van Dijken, G., and Long, M.: Coastal Southern Ocean: A
strong anthropogenic CO2 sink, Geophys. Res. Lett., 35, L21602, https://doi.org/10.1029/2008GL035624, 2008. a
Bigdeli, A., Nguyen, A. T., Pillar, H., Ocaña, V., and Heimbach, P.:
Atmospheric Warming Drives Growth in Arctic Sea-Ice: A Key Role for Snow,
Geophys. Res. Lett., 47, e2020GL090236, https://doi.org/10.1029/2020GL090236, 2020. a
Bronselaer, B., Winton, M., Griffies, S. M., Hurlin, W. J., Rodgers, K. B.,
Sergienko, O. V., Stouffer, R. J., and Russell, J. L.: Change in future
climate due to Antarctic meltwater, Nature, 564, 53–58, 2018. a
Chaudhuri, A. H., Ponte, R. M., Forget, G., and Heimbach, P.: A comparison of
atmospheric reanalysis surface products over the ocean and implications for
uncertainties in air–sea boundary forcing, J. Climate, 26, 153–170,
2013. a
De Rydt, J., Holland, P., Dutrieux, P., and Jenkins, A.: Geometric and
oceanographic controls on melting beneath Pine Island Glacier, J. Geophys. Res.-Oceans, 119, 2420–2438, 2014. a
Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli, P.,
Kobayashi, S., Andrae, U., Balmaseda, M. A., Balsamo, G., Bauer, P.,
Bechtold, P., Beljaars, A. C. M., van de Berg, I., Biblot, J., Bormann, N.,
Delsol, C., Dragani, R., Fuentes, M., Greer, A. J., Haimberger, L., Healy, S.
B., Hersbach, H., Holm, E. V., Isaksen, L., Kallberg, P., Kohler, M.,
Matricardi, M., McNally, A. P., Mong-Sanz, B. M., Morcette, J.-J., Park,
B.-K., Peubey, C., de Rosnay, P., Tavolato, C., Thepaut, J. N., and Vitart,
F.: The ERA-Interim reanalysis: Configuration and performance of the data
assimilation system, Q. J. Roy. Meteorol. Soc., 137, 553–597, doi:10.1002/qj.828, 2011. a
Dinniman, M. S., Asay-Davis, X. S., Galton-Fenzi, B. K., Holland, P. R.,
Jenkins, A., and Timmermann, R.: Modeling ice shelf/ocean interaction in Antarctica: A review, Oceanography, 29, 144–153, 2016. a
Ducklow, H., Clarke, A., Dickhut, R., Doney, S. C., Geisz, H., Huang, K., Martinson, D. G., Meredith, M. P., Moeller, H. V., Montes-Hugo, M., Schofield, O., Stammerjohn, S. E., Steinberg, D., and Fraser, W.:
The marine system of the Western Antarctic Peninsula, Antarctic ecosystems:
an extreme environment in a changing world, Blackwell Publishing Ltd., 121–159, 2012. a, b
Fenty, I. and Heimbach, P.: Hydrographic preconditioning for seasonal sea ice
anomalies in the Labrador Sea, J. Phys. Oceanogr., 43,
863–883, 2013b. a
Fretwell, P., Pritchard, H. D., Vaughan, D. G., Bamber, J. L., Barrand, N. E., Bell, R., Bianchi, C., Bingham, R. G., Blankenship, D. D., Casassa, G., Catania, G., Callens, D., Conway, H., Cook, A. J., Corr, H. F. J., Damaske, D., Damm, V., Ferraccioli, F., Forsberg, R., Fujita, S., Gim, Y., Gogineni, P., Griggs, J. A., Hindmarsh, R. C. A., Holmlund, P., Holt, J. W., Jacobel, R. W., Jenkins, A., Jokat, W., Jordan, T., King, E. C., Kohler, J., Krabill, W., Riger-Kusk, M., Langley, K. A., Leitchenkov, G., Leuschen, C., Luyendyk, B. P., Matsuoka, K., Mouginot, J., Nitsche, F. O., Nogi, Y., Nost, O. A., Popov, S. V., Rignot, E., Rippin, D. M., Rivera, A., Roberts, J., Ross, N., Siegert, M. J., Smith, A. M., Steinhage, D., Studinger, M., Sun, B., Tinto, B. K., Welch, B. C., Wilson, D., Young, D. A., Xiangbin, C., and Zirizzotti, A.: Bedmap2: improved ice bed, surface and thickness datasets for Antarctica, The Cryosphere, 7, 375–393, https://doi.org/10.5194/tc-7-375-2013, 2013. a
Fukumori, I., Wang, O., Fenty, I., Forget, G., Heimbach, P., and Ponte, R. M.: Synopsis of the ECCO Central Production Global Ocean and Sea-Ice State Estimate, Zenodo, https://doi.org/10.5281/zenodo.3765929, 2020. a, b
Giering, R. and Kaminski, T.: Recipes for adjoint code construction, ACM
Transactions on Mathematical Software (TOMS), 24, 437–474, 1998. a
Giering, R. and Kaminski, T.: Applying TAF to generate efficient derivative
code of Fortran 77-95 programs, in: PAMM: Proceedings in Applied Mathematics
and Mechanics, vol. 2, pp. 54–57, Wiley Online Library, 2003. a
Gille, S. T., McKee, D. C., and Martinson, D. G.: Temporal Changes in the Antarctic Circumpolar Current, Oceanography, 29, 96–105, 2016. a
Heimbach, P. and Losch, M.: Adjoint sensitivities of sub-ice shelf melt rates
to ocean circulation under Pine Island Ice Shelf, West Antarctica, Ann. Glaciol., 53, 59–69, 2012. a
Hellmer, H. and Olbers, D.: A two-dimensional model for the thermohaline
circulation under an ice shelf, Antarct. Sci., 1, 325–336, 1989. a
Henderson, A., Ahrens, J., and Law, C.: The ParaView Guide, vol. 366, Kitware Clifton Park, NY, 2004. a
Heywood, K. J., Biddle, L. C., Boehme, L., Dutrieux, P., Fedak, M., Jenkins, A., Jones, R. W., Kaiser, J., Mallett, H., Garabato, A. C. N., Renfrew I. A., Stevens D. P., and Webber B. G. M.:
Between the devil and the deep blue sea: the role of the Amundsen Sea
continental shelf in exchanges between ocean and ice shelves, Oceanography,
29, 118–129, 2016. a, b, c, d, e
Jacobs, S. S., Hellmer, H. H., and Jenkins, A.: Antarctic ice sheet melting in
the Southeast Pacific, Geophys. Res. Lett., 23, 957–960, 1996. a
Jenkins, A.: A one-dimensional model of ice shelf-ocean interaction, J. Geophys. Res.-Oceans, 96, 20671–20677, 1991. a
Jenkins, A., Shoosmith, D., Dutrieux, P., Jacobs, S., Kim, T. W., Lee, S. H.,
Ha, H. K., and Stammerjohn, S.: West Antarctic Ice Sheet retreat in the Amundsen Sea driven by decadal oceanic variability, Nat. Geosci.,
11, 733–738, 2018. a
Jones, D. C., Meijers, A. J., Shuckburgh, E., Sallée, J.-B., Haynes, P.,
McAufield, E. K., and Mazloff, M. R.: How does Subantarctic Mode Water
ventilate the Southern Hemisphere subtropics?, J. Geophys. Res.-Oceans, 121, 6558–6582, 2016. a
Jones, D. C., Boland, E., Meijers, A. J., Forget, G., Josey, S., Sallée, J.-B., and Shuckburgh, E.: The sensitivity of Southeast Pacific heat
distribution to local and remote changes in ocean properties, J. Phys. Oceanogr., 50, 773–790, 2020. a
Jourdain, N. C., Mathiot, P., Merino, N., Durand, G., Le Sommer, J., Spence, P., Dutrieux, P., and Madec, G.: Ocean circulation and sea-ice thinning
induced by melting ice shelves in the Amundsen Sea, J. Geophys. Res.-Oceans, 122, 2550–2573, 2017. a
Kimura, S., Jenkins, A., Regan, H., Holland, P. R., Assmann, K. M., Whitt, D. B., Van Wessem, M., van de Berg, W. J., Reijmer, C. H., and Dutrieux, P.:
Oceanographic controls on the variability of ice-shelf basal melting and
circulation of glacial meltwater in the Amundsen Sea Embayment, Antarctica,
J. Geophys. Res.-Oceans, 122, 10131–10155, 2017. a
Kusahara, K.: Interannual-to-Multidecadal Responses of Antarctic Ice
Shelf–Ocean Interaction and Coastal Water Masses during the Twentieth
Century and the Early Twenty-First Century to Dynamic and Thermodynamic
Forcing, J. Climate, 33, 4941–4973, 2020. a
Kusahara, K. and Hasumi, H.: Modeling Antarctic ice shelf responses to future
climate changes and impacts on the ocean, J. Geophys. Res.-Oceans, 118, 2454–2475, 2013. a
Le Dimet, F.-X. and Talagrand, O.: Variational algorithms for analysis and
assimilation of meteorological observations: theoretical aspects, Tellus A, 38, 97–110, 1986. a
Losch, M.: Modeling ice shelf cavities in a z coordinate ocean general
circulation model, J. Geophys. Res.-Oceans, 113, C08043, https://doi.org/10.1029/2007JC004368, 2008. a
Losch, M., Menemenlis, D., Heimbach, P., Campin, J.-M., and Hill, C.: On the
formulation of sea-ice models. Part 1: Effects of different solver
implementations and parameterizations, Ocean Model., 33, 129–144, 2010. a
Nakayama, Y.: MITgcm model setup and output for “Development of adjoint-based ocean state estimation for the Amundsen and Bellingshausen Seas and ice shelf cavities using MITgcm/ECCO” (Version MITgcm(66j)) [Data set], Zenodo, https://doi.org/10.5281/zenodo.4541036, 2021. a, b
Nakayama, Y., Timmermann, R., Schröder, M., and Hellmer, H.: On the
difficulty of modeling Circumpolar Deep Water intrusions onto the Amundsen Sea continental shelf, Ocean Model., 84, 26–34, 2014. a
Nakayama, Y., Manucharayan, G., Kelin, P., Torres, H. G., Schodlok, M., Rignot, E., Dutrieux, P., and Menemenlis, D.: Pathway of Circumpolar Deep Water
into Pine Island and Thwaites ice shelf cavities and to their grounding
lines, Sci. Rep.-UK, 9, 16649, https://doi.org/10.1038/s41598-019-53190-6, 2019. a
Nguyen, A. T., Pillar, H., Ocana, V., Bigdeli, A., Smith, T. A., and Heimbach, P.: The Arctic Subpolar gyre sTate Estimate (ASTE): Description and
assessment of a data-constrained, dynamically consistent ocean-sea ice
estimate for 2002–2017, Earth and Space Science Open Archive, https://doi.org/10.1002/essoar.10504669.2, 2020. a
Paolo, F. S., Fricker, H. A., and Padman, L.: Volume loss from Antarctic ice
shelves is accelerating, Science, 348, 327–331, 2015. a
Pritchard, H. D., Ligtenberg, S. R. M., Fricker, H. A., Vaughan, D. G., Van den
Broeke, M. R., and Padman, L.: Antarctic ice-sheet loss driven by basal
melting of ice shelves, Nature, 484, 502–505, 2012. a
Rignot, E., Mouginot, J., Scheuchl, B., van den Broeke, M., van Wessem, M. J.,
and Morlighem, M.: Four decades of Antarctic Ice Sheet mass balance from
1979–2017, P. Natl. Acad. Sci. USA, 116, 1095–1103,
2019. a
Roach, C. J. and Speer, K.: Exchange of water between the Ross Gyre and ACC assessed by Lagrangian particle tracking, J. Geophys. Res.-Oceans, 124, 4631–4643, 2019. a
Rodriguez, A. R., Mazloff, M. R., and Gille, S. T.: An oceanic heat transport
pathway to the Amundsen Sea Embayment, J. Geophys. Res.-Oceans, 121, 3337–3349, 2016. a
Roquet, F., Wunsch, C., Forget, G., Heimbach, P., Guinet, C., Reverdin, G., Charrassin, J.-B., Bailleul, F., Costa, D. P., Huckstadt, L. A., Goetz, K., T., Kovacs, K. M., Lydersen, C., Biuw, M., Nøst, O, A., Bornemann, H., Ploetz, J., Bester, M. N., McIntyre, T., Muelbert, M. C., Hindell, M. A., McMahon, C. R., Williams, G., Harcourt, R., Field, I. C., Chafik, L., Nicholls, K. W., Boehme, L., and Fedak, M. A.:
Estimates of the Southern Ocean general circulation improved by animal-borne
instruments, Geophys. Res. Lett., 40, 6176–6180, 2013. a, b
Rudnick, D. L., Gopalakrishnan, G., and Cornuelle, B. D.: Cyclonic eddies in
the Gulf of Mexico: Observations by underwater gliders and simulations by
numerical model, J. Phys. Oceanogr., 45, 313–326, 2015. a
Schlitzer, R.: Ocean data view, Alfred Wegener Institute for Polar and Marine Research, Bermerhaven, Germany, 2004. a
Schodlok, M. P., Menemenlis, D., Rignot, E., and Studinger, M.: Sensitivity of
the ice shelf ocean system to the sub-ice shelf cavity shape measured by NASA IceBridge in Pine Island Glacier, West Antarctica,
Ann. Glaciol., 53, 156–162, 2012. a
Tamsitt, V., Drake, H. F., Morrison, A. K., Talley, L. D., Du- four, C. O., Gray, A. R., Griffies, S. M., Mazloff, M. R., Sarmiento, J. L., Wang, J., and Weijer, W.:
Spiraling pathways of global deep waters to the surface of the Southern Ocean, Nat. Commun., 8, 1–10, 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
Verdy, A., Mazloff, M. R., Cornuelle, B. D., and Kim, S. Y.: Wind-driven sea
level variability on the California coast: An adjoint sensitivity analysis,
J. Phys. Oceanogr., 44, 297–318, 2014. a
Verdy, A., Cornuelle, B., Mazloff, M. R., and Rudnick, D. L.: Estimation of the
tropical Pacific Ocean state 2010–13, J. Atmos. Ocean. Tech., 34, 1501–1517, 2017. a
Vinogradova, N. T., Ponte, R. M., Fukumori, I., and Wang, O.: Estimating
satellite salinity errors for assimilation of Aquarius and SMOS
data into climate models, J. Geophys. Res.-Oceans, 119,
4732–4744, 2014. a
Walker, D. P., Brandon, M. A., Jenkins, A., Allen, J. T., Dowdeswell, J. A.,
and Evans, J.: Oceanic heat transport onto the Amundsen Sea shelf through
a submarine glacial trough, Geophys. Res. Lett., 34, 1–4, 2007. a
Walker, D. P., Jenkins, A., Assmann, K. M., Shoosmith, D. R., and Brandon, M. A.: Oceanographic observations at the shelf break of the Amundsen Sea, Antarctica, J. Geophys. Res., 118, 2906–2918, 2013. a
Webber, B. G., Heywood, K. J., Stevens, D. P., and Assmann, K. M.: The impact
of overturning and horizontal circulation in Pine Island Trough on ice
shelf melt in the eastern Amundsen Sea, J. Phys. Oceanogr.,
49, 63–83, 2019. a
Wunsch, C. and Heimbach, P.: Dynamically and kinematically consistent global
ocean circulation and ice state estimates, in: International Geophysics, vol.
103, pp. 553–579, Elsevier, 2013. a
Wunsch, C., Heimbach, P., Ponte, R. M., Fukumori, I., and MEMBERS, E.-G. C.:
The global general circulation of the ocean estimated by the ECCO-Consortium, Oceanography, 22, 88–103, 2009. a
Zhang, X., Thompson, A. F., Flexas, M. M., Roquet, F., and Bornemann, H.:
Circulation and meltwater distribution in the Bellingshausen Sea: from
shelf break to coast, Geophys. Res. Lett., 43, 6402–6409, 2016. a
Short summary
High ice shelf melting in the Amundsen Sea has attracted many observational campaigns in the past decade. One method to combine observations with numerical models is the adjoint method. After 20 iterations, the cost function, defined as a sum of the weighted model–data difference, is reduced by 65 % by adjusting initial conditions, atmospheric forcing, and vertical diffusivity. This study demonstrates adjoint-method optimization with explicit representation of ice shelf cavity circulation.
High ice shelf melting in the Amundsen Sea has attracted many observational campaigns in the...
