Holocene climate at Siple Dome, West Antarctica, using bubble number-density.

Wednesday, 17 December 2014
Matthew Keith Spencer1, Andrew Dennison1, Richard B Alley2, Joan J Fitzpatrick3 and John M Fegyveresi4, (1)Lake Superior State University, Sault Saint Marie, MI, United States, (2)Pennsylvania State Univ, University Park, PA, United States, (3)USGS, Denver, CO, United States, (4)The Pennsylvania State University, University Park, PA, United States
Past allowable accumulation rate/temperature combinations from Holocene ice core samples at Siple Dome, West Antarctica, are estimated from the measured number-density of bubbles. Mass density increase and grain growth in polar firn both are controlled by temperature and accumulation rate, and their integrated effects are recorded in the number-density of bubbles as the firn changes to ice1, 2. Siple Dome bubble number-densities show an early-Holocene high in accumulation rate followed by an approximately 10% reduction in accumulation rate between 11.33 ka and 1.863 ka.

1. Spencer, M.K., R.B. Alley and J.J. Fitzpatrick. Developing a bubble number-density paleoclimatic indicator for glacier ice, J. Glaciol. 52(178), 358-364 (2006).

2. J.M. Fegyveresi, et al., Late-Holocene climate evolution at the WAIS Divide site, West Antarctica: bubble number-density estimates, J. Glaciol., 57(204) , 629 – 638 (2011).