TY - JOUR
T1 - A topographic hinge-zone divides coastal and inland ice dynamic regimes in East Antarctica
AU - Andersen, Jane L.
AU - Newall, Jennifer C.
AU - Fredin, Ola
AU - Glasser, Neil F.
AU - Lifton, Nathaniel A.
AU - Stuart, Finlay M.
AU - Fabel, Derek
AU - Caffee, Marc
AU - Pedersen, Vivi K.
AU - Koester, Alexandria J.
AU - Suganuma, Yusuke
AU - Harbor, Jonathan M.
AU - Stroeven, Arjen P.
N1 - Funding Information:
This material is based upon work supported by Stockholm University (A.P.S.), Norwegian Polar Institute/NARE under Grant “MAGIC-DML” (O.F.), the US National Science Foundation under Grant No. PLR-1542930 (N.L. & J.M.H.) and EAR-1560658 (M.W.C.), Swedish Research Council under Grant No. 2016-04422 (J.M.H. & A.P.S.). J.L.A. was supported by a Carlsberg Foundation Fellowship and a Wenner-Gren Foundations stipend. VKP was supported by Villum Fonden (Grant no. 15467). We thank the Swedish Polar Research Secretariat for logistical support, UNAVCO for providing the dGPS, and Polar Geospatial Center for provision of satellite data used for navigation in the field. Permission to work and collect geological samples in Antarctica was arranged through the Swedish Polar Research Secretariat. We thank Maria Miguens-Rodriguez for help with sample preparation at SUERC. We thank David L. Egholm for providing an early version of the inversion code and valuable feedback on the manuscript. We thank David Small, David Sugden and an anonymous reviewer for constructive feedback that helped improve the manuscript.
Publisher Copyright:
© 2023, The Author(s).
PY - 2023/1/5
Y1 - 2023/1/5
N2 - The impact of late Cenozoic climate on the East Antarctic Ice Sheet is uncertain. Poorly constrained patterns of relative ice thinning and thickening impair the reconstruction of past ice-sheet dynamics and global sea-level budgets. Here we quantify long-term ice cover of mountains protruding the ice-sheet surface in western Dronning Maud Land, using cosmogenic Chlorine-36, Aluminium-26, Beryllium-10, and Neon-21 from bedrock in an inverse modeling approach. We find that near-coastal sites experienced ice burial up to 75–97% of time since 1 Ma, while interior sites only experienced brief periods of ice burial, generally <20% of time since 1 Ma. Based on these results, we suggest that the escarpment in Dronning Maud Land acts as a hinge-zone, where ice-dynamic changes driven by grounding-line migration are attenuated inland from the coastal portions of the East Antarctic Ice Sheet, and where precipitation-controlled ice-thickness variations on the polar plateau taper off towards the coast.
AB - The impact of late Cenozoic climate on the East Antarctic Ice Sheet is uncertain. Poorly constrained patterns of relative ice thinning and thickening impair the reconstruction of past ice-sheet dynamics and global sea-level budgets. Here we quantify long-term ice cover of mountains protruding the ice-sheet surface in western Dronning Maud Land, using cosmogenic Chlorine-36, Aluminium-26, Beryllium-10, and Neon-21 from bedrock in an inverse modeling approach. We find that near-coastal sites experienced ice burial up to 75–97% of time since 1 Ma, while interior sites only experienced brief periods of ice burial, generally <20% of time since 1 Ma. Based on these results, we suggest that the escarpment in Dronning Maud Land acts as a hinge-zone, where ice-dynamic changes driven by grounding-line migration are attenuated inland from the coastal portions of the East Antarctic Ice Sheet, and where precipitation-controlled ice-thickness variations on the polar plateau taper off towards the coast.
UR - http://www.scopus.com/inward/record.url?scp=85145718538&partnerID=8YFLogxK
U2 - 10.1038/s43247-022-00673-6
DO - 10.1038/s43247-022-00673-6
M3 - Article
AN - SCOPUS:85145718538
SN - 2662-4435
VL - 4
JO - Communications Earth and Environment
JF - Communications Earth and Environment
IS - 1
M1 - 9
ER -
