The 1500 m South Pole ice core: recovering a 40 ka environmental record

Supported by the US National Science Foundation, a new 1500 m, ∼40 ka old ice core will be recovered from South Pole during the 2014/15 and 2015/16 austral summer seasons using the new US intermediate-depth drill. The combination of low temperatures, relatively high accumulation rates and low impurity concentrations at South Pole will yield detailed records of ice chemistry and trace atmospheric gases. The South Pole ice core will provide a climate history record of a unique area of the East Antarctic plateau that is partly influenced by weather systems that cross the West Antarctic ice sheet. The ice at South Pole flows at ∼ 10ma−1 and the South Pole ice-core site is a significant distance from an ice divide. Therefore, ice recovered at depth originated progressively farther upstream of the coring site. New ground-penetrating radar collected over the drill site location shows no anthropogenic influence over the past ∼50 years or upper 15 m. Depth–age scale modeling results show consistent and plausible annual-layer thicknesses and accumulation rate histories, indicating that no significant stratigraphic disturbances exist in the upper 1500 m near the ice-core drill site.