Last Interglacial climate 1 and sea-level evolution from a coupled ice sheet-climate model

• Main Authors: Goelzer, H., Huybrechts, P., Loutre, Marie-France, Fichefet, Thierry
• Other Authors: UCL - SST/ELI/ELIC - Earth & Climate
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus GmbH 2016
• Subjects: CISM:CECI; 1443; Antarctic; Greenland; The Antarctic; Antarc*; Ice Sheet; Ice Shelf; Sea ice
• Online Access: http://hdl.handle.net/2078.1/171213; https://doi.org/10.5194/cp-2015-175

As the most recent warm period in Earth’s history with a sea-level stand higher than present,the Last Interglacial period (~130 to 115 kyr BP) is often considered a prime example to studythe impact of a warmer climate on the two polar ice sheets remaining today. Here we simulatethe Last Interglacial climate, ice sheet and sea-level evolution with the Earth system model of intermediate complexity LOVECLIM v.1.3, which includes dynamic and fully-coupled components representing the atmosphere, the ocean and sea ice, the terrestrial biosphere and the Greenland and Antarctic ice sheets. In this set-up, sea-level evolution and climate-ice sheet interactions are modelled in a consistent framework. Surface mass balance changes are the dominant forcing for the Greenland ice sheet, which shows a peak sea-level contribution of 1.4 m at 123 kyr BP in the reference experiment. Our results indicate that ice sheet-climate feedbacks play an important role to amplify climate and sea-level changes in the Northern Hemisphere. The sensitivity of the Greenland ice sheet to surface temperature changes considerably increases when interactive albedo changes are considered. Southern Hemisphere polar and sub-polar ocean warming is limited throughout the Last Interglacial and surface and sub-shelf melting exerts 29 only a minor control on the Antarctic sea-level contribution with a peak of 4.4 m at 125 kyr BP. Retreat of the Antarctic ice sheet at the onset of the LIG is mainly forced by rising sea-level and reduced ice shelf viscosity as the surface temperature increases. Global sea level shows a peak of 5.3 m at 124.5 kyr BP, which includes a minor contribution of 0.35 m from oceanic thermal expansion. Neither the individual contributions nor the total modelled sea-level stand show multi35 millennial time scale variations as indicated by some reconstructions.