Rapid coupling between ice volume and polar temperature over the past 150,000 years

• Published in: Nature
• Main Authors: Grant, Katharine, Rohling, Eelco, Bar-Matthews, M, Ayalon, A, Medina-Elizalde, M, Bronk Ramsey, C., Satow, C, Roberts, Andrew
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Macmillan Publishers Ltd
• Subjects: Antarctic; Greenland; Antarc*; ice core
• Online Access: http://hdl.handle.net/1885/103691; https://doi.org/10.1038/nature11593; https://openresearch-repository.anu.edu.au/bitstream/1885/103691/5/01_Grant_Rapid_coupling_between_ice_2012.pdf.jpg

Current global warming necessitates a detailed understanding of the relationships between climate and global ice volume. Highly resolved and continuous sea-level records are essential for quantifying ice-volume changes. However, an unbiased study of the timing of past ice-volume changes, relative to polar climate change, has so far been impossible because available sea-level records either were dated by using orbital tuning or ice-core timescales, or were discontinuous in time. Here we present an independent dating of a continuous, high-resolution sea-level record1, 2 in millennial-scale detail throughout the past 150,000 years. We find that the timing of ice-volume fluctuations agrees well with that of variations in Antarctic climate and especially Greenland climate. Amplitudes of ice-volume fluctuations more closely match Antarctic (rather than Greenland) climate changes. Polar climate and ice-volume changes, and their rates of change, are found to covary within centennial response times. Finally, rates of sea-level rise reached at least 1.2 m per century during all major episodes of ice-volume reduction.