High Climate Model Dependency of Pliocene Antarctic Ice-Sheet Predictions

• Main Authors: Dolan, AM, de Boer, B, Bernales, J, Hill, DJ, Haywood, AM
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Nature 2018
• Subjects: Antarctic; The Antarctic; West Antarctica; Antarc*; Antarctica; Ice Sheet
• Online Access: https://eprints.whiterose.ac.uk/131951/; https://eprints.whiterose.ac.uk/131951/8/s41467-018-05179-4.pdf

The mid-Pliocene warm period provides a natural laboratory to investigate the long-term response of the Earth’s ice-sheets and sea level in a warmer-than-present-day world. Proxy data suggest that during the warm Pliocene, portions of the Antarctic ice-sheets, including West Antarctica could have been lost. Ice-sheet modelling forced by Pliocene climate model outputs is an essential way to improve our understanding of ice-sheets during the Pliocene. However, uncertainty exists regarding the degree to which results are model-dependent. Using climatological forcing from an international climate modelling intercomparison project, we demonstrate the high dependency of Antarctic ice-sheet volume predictions on the climate model-based forcing used. In addition, the collapse of the vulnerable marine basins of Antarctica is dependent on the ice-sheet model used. These results demonstrate that great caution is required in order to avoid making unsound statements about the nature of the Pliocene Antarctic ice-sheet based on model results that do not account for structural uncertainty in both the climate and ice sheet models.