@article{5907f1bf1a49433cbff9580f306c7d8a,
title = "Heterogeneous melting near the Thwaites Glacier grounding line",
abstract = "Thwaites Glacier represents 15% of the ice discharge from the West Antarctic Ice Sheet and influences a wider catchment1–3. Because it is grounded below sea level4,5, Thwaites Glacier is thought to be susceptible to runaway retreat triggered at the grounding line (GL) at which the glacier reaches the ocean6,7. Recent ice-flow acceleration2,8 and retreat of the ice front8–10 and GL11,12 indicate that ice loss will continue. The relative impacts of mechanisms underlying recent retreat are however uncertain. Here we show sustained GL retreat from at least 2011 to 2020 and resolve mechanisms of ice-shelf melt at the submetre scale. Our conclusions are based on observations of the Thwaites Eastern Ice Shelf (TEIS) from an underwater vehicle, extending from the GL to 3 km oceanward and from the ice–ocean interface to the sea floor. These observations show a rough ice base above a sea floor sloping upward towards the GL and an ocean cavity in which the warmest water exceeds 2 °C above freezing. Data closest to the ice base show that enhanced melting occurs along sloped surfaces that initiate near the GL and evolve into steep-sided terraces. This pronounced melting along steep ice faces, including in crevasses, produces stratification that suppresses melt along flat interfaces. These data imply that slope-dependent melting sculpts the ice base and acts as an important response to ocean warming.",
author = "Schmidt, {B. E.} and P. Washam and Davis, {P. E.D.} and Nicholls, {K. W.} and Holland, {D. M.} and Lawrence, {J. D.} and Riverman, {K. L.} and Smith, {J. A.} and A. Spears and Dichek, {D. J.G.} and Mullen, {A. D.} and E. Clyne and B. Yeager and P. Anker and Meister, {M. R.} and Hurwitz, {B. C.} and Quartini, {E. S.} and Bryson, {F. E.} and A. Basinski-Ferris and C. Thomas and J. Wake and Vaughan, {D. G.} and S. Anandakrishnan and E. Rignot and J. Paden and K. Makinson",
note = "Funding Information: We thank the personnel from the United States Antarctic Program and the British Antarctic Survey, without whom these data could not be collected. Fieldwork and support for analysis was provided by the NSF-NERC International Thwaites Glacier Collaboration (ITGC), financed by NSF OPP grant 1739003 (US), NERC NE/S006656/1, NERC NE/S006761/1 and NERC NE/S006427/1 (UK). We recognize the support of the ITGC staff and scientists in the execution of this ambitious field campaign. The Icefin team acknowledges past Georgia Tech team members who helped develop and field the vehicle: J. Lutz, M. {\textquoteleft}Kit{\textquoteright} Philleo, C. Ramey, C. Walker, J. Buffo, T. Hobbs and School of Earth and Atmospheric Sciences (EAS) chair G. Huey and the EAS staff who supported this work. The Icefin vehicle was initially developed with funding from Georgia Institute of Technology and startup funds for B.E.S. Now in its third version, Icefin was redesigned under NASA grant NNX16AL07G, principal investigator B.E.S. The Icefin project is now located at Cornell University. Funding Information: We thank the personnel from the United States Antarctic Program and the British Antarctic Survey, without whom these data could not be collected. Fieldwork and support for analysis was provided by the NSF-NERC International Thwaites Glacier Collaboration (ITGC), financed by NSF OPP grant 1739003 (US), NERC NE/S006656/1, NERC NE/S006761/1 and NERC NE/S006427/1 (UK). We recognize the support of the ITGC staff and scientists in the execution of this ambitious field campaign. The Icefin team acknowledges past Georgia Tech team members who helped develop and field the vehicle: J. Lutz, M. {\textquoteleft}Kit{\textquoteright} Philleo, C. Ramey, C. Walker, J. Buffo, T. Hobbs and School of Earth and Atmospheric Sciences (EAS) chair G. Huey and the EAS staff who supported this work. The Icefin vehicle was initially developed with funding from Georgia Institute of Technology and startup funds for B.E.S. Now in its third version, Icefin was redesigned under NASA grant NNX16AL07G, principal investigator B.E.S. The Icefin project is now located at Cornell University. Publisher Copyright: {\textcopyright} 2023, The Author(s), under exclusive licence to Springer Nature Limited.",
year = "2023",
month = feb,
day = "16",
doi = "10.1038/s41586-022-05691-0",
language = "English (US)",
volume = "614",
pages = "471--478",
journal = "Nature",
issn = "0028-0836",
publisher = "Nature Publishing Group",
number = "7948",
}