Holocene Glacier and Climate Fluctuations

Evidence for smaller ice volumes/ice extents during the mid-late Holocene relative to the present day is available at a number of sites. Sediments from the bed of epishelf Moutoneee Lake indicate the free movement of icebergs, and therefore the collapse of the George VI Ice Shelf between Alexander Island and the Antarctic Peninsula, between 9.6 and 8cal. ka B.P (Bentley et al., 2005). Likewise the analysis of sediment cores recovered from the seabed of the Prince Gustav Channel on the eastern side of the peninsula, has determined that between 5 and 2 ka BP clasts were sourced from a range of distal locations, indicating open marine conditions and the collapse of the Prince Gustav Channel Ice Shelf (Pudsey and Evans, 2001). Neither is the mid-Holocene minimum confined to the Antarctic Peninsula. Goodwin (1996) provides evidence from a number of sources that Law Dome was at least 3-4 km smaller before ~4ka BP, while Baroni and Orombelli (1994) show that ice shelves in Terra Nova Bay were reduced by a similar amount between 7.5 and 5ka BP.

On the contrary, there is geological evidence to suggest that the Larsen Ice Shelf B had been in place for > 11 ka before its collapse in 2002 (Domack et al., 2005). In East Antarctica, Verleyen et al. (2005) provide relative sea level (RSL) based evidence for increased ice load near the Larsemann Hills between ~7 and 2.5 ka BP. Given the similarity of the RSL curve to that obtained from the Vestfold Hills (Zwartz et al., 1998) this may have been more than a local feature. This fluctuation may correlate with the glacial advances identified through striae patterns and weathering in the Vestfold Hills (Adamson and Pickard, 1986) and in the Rauer Group (White et al., submitted).

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