Asynchronous Antarctic and Greenland ice-volume contributions to the last interglacial sea-level highstand

• Published in: Nature Communications
• Main Authors: Rohling, Eelco, Hibbert, Fiona, Grant, Katharine, Galaasen, Eirik V., Irvalı, Nil, Kleiven, Helga F., Marino, Gianluca, Ninnemann, Ulysses, Roberts, Andrew P., Rosenthal, Y, Schulz, H, Williams, Felicity, Yu, Jimin
• Format: Article in Journal/Newspaper
• Language: English
• Published: Macmillan Publishers Ltd
• Subjects: Antarctic; Greenland; Antarc*; Ice Sheet; Ice Shelf
• Online Access: http://hdl.handle.net/1885/206419; https://doi.org/10.1038/s41467-019-12874-3; https://openresearch-repository.anu.edu.au/bitstream/1885/206419/3/01_Rohling_Asynchronous_Antarctic_and_2019.pdf.jpg

The last interglacial (LIG; ~130 to ~118 thousand years ago, ka) was the last time global sea level rose well above the present level. Greenland Ice Sheet (GrIS) contributions were insufficient to explain the highstand, so that substantial Antarctic Ice Sheet (AIS) reduction is implied. However, the nature and drivers of GrIS and AIS reductions remain enigmatic, even though they may be critical for understanding future sea-level rise. Here we complement existing records with new data, and reveal that the LIG contained an AIS-derived highstand from ~129.5 to ~125 ka, a lowstand centred on 125–124 ka, and joint AIS + GrIS contributions from ~123.5 to ~118 ka. Moreover, a dual substructure within the first highstand suggests temporal variability in the AIS contributions. Implied rates of sea-level rise are high (up to several meters per century; m c−1 ), and lend credibility to high rates inferred by ice modelling under certain ice-shelf instability parameterisations. This research contributes to Australian Research Council Laureate Fellowship FL120100050 (to E.J.R.). UiB contribution (to E.V.G., N.I., K.K. and U.N.) supported by RCN project THRESHOLDS (25496). G.M. acknowledges generous support from the University of Vigo