Ice-stream initiation, duration and thinning on James Ross Island, northern Antarctic Peninsula

• Published in: Quaternary Science Reviews
• Main Authors: Glasser, NF, Davies, BJ, Carrivick, JL, Rodés, A, Hambrey, MJ, Smellie, JL, Domack, E
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2014
• Subjects: Antarctic; Antarctic Peninsula; Prince Gustav Channel; Ross Island; The Antarctic; Antarc*; Ice Sheet; James Ross Island
• Online Access: https://eprints.whiterose.ac.uk/77904/; https://eprints.whiterose.ac.uk/77904/7/CarrivickIce-Stream%20Initiation_.pdf; https://doi.org/10.1016/j.quascirev.2013.11.012

Predicting the future response of the Antarctic Ice Sheet to climate change requires an understanding of the ice streams that dominate its dynamics. Here we use cosmogenic isotope exposure-age dating (Al, Be and Cl) of erratic boulders on ice-free land on James Ross Island, north-eastern Antarctic Peninsula, to define the evolution of Last Glacial Maximum (LGM) ice in the adjacent Prince Gustav Channel. These data include ice-sheet extent, thickness and dynamical behaviour. Prior to ~18ka, the LGM Antarctic Peninsula Ice Sheet extended to the continental shelf-edge and transported erratic boulders onto high-elevation mesas on James Ross Island. After ~18ka there was a period of rapid ice-sheet surface-lowering, coincident with the initiation of the Prince Gustav Ice Stream. This timing coincided with rapid increases in atmospheric temperature and eustatic sea-level rise around the Antarctic Peninsula. Collectively, these data provide evidence for a transition from a thick, cold-based LGM Antarctic Peninsula Ice Sheet to a thinner, partially warm-based ice sheet during deglaciation.