C53C-0337:
A new age constraint on the deglaciation of the Ross Sea from an ice core from Roosevelt Island, East Ross Sea, Antarctica
Friday, 19 December 2014
James Edward Lee, Oregon State University, Corvallis, OR, United States, Edward Brook, Oregon State Univ, Corvallis, OR, United States, Thomas Blunier, Niels Bohr Institute - University of Copenhagen, Copenhagen, Denmark, Nancy A.N. Bertler, Victoria University of Wellington, Antarctic Research Centre, Wellington, New Zealand and Paul Travis Vallelonga, Centre for Ice and Climate, Copenhagen, Denmark
Abstract:
A new ice core from Roosevelt Island was drilled for the Roosevelt Island Climate Evolution (RICE) project to establish the history of deglaciation of the Ross Sea through the Holocene. Evidence of glacial retreat in the Ross Sea Embayment shows that deglaciation happened in several stages of rapid collapse and persisted well after the melting of the Northern Hemisphere ice sheets was complete. The ice rise on Roosevelt Island should record the timing of the recession of the West Antarctic Ice Sheet (WAIS) past Roosevelt Island. The transition between ice originating from WAIS and ice originating local to Roosevelt Island could, in principle, be identified in the RICE ice core by the Total Air Content (TAC), which depends on surface air pressure and climate. Because the accumulation zone of WAIS is at a higher altitude than Roosevelt Island, it is expected that TAC will record a sharp drop during the transition. Existing data back to 3.7 ka show a relatively constant air content, probably implying only small elevation changes over that time. New results from deeper sections will be discussed at the meeting.
