V. Ya. Lipenkov, A. N. Salamatin, A. A. Ekaykin. Paleoclimate reconstructions based on deep ice core and snow pit studies at Vostok station

The problems linked to paleoclimatic interpretation of the data obtained from the deep 5G-1 ice core and snow pits at Vostok Station are discussed. It is shown that over the past 410 kyr, the glacial-interglacial warming in the central part of Antarctica preceded CO₂ increase in the atmosphere by about 1 kyr, while the thickening of the Antarctic ice sheet and see level raise lagged the warming by at least 3 kyr. The thickening of the ice sheet in the region of Vostok Station by 100-150 m due to an increase in snow precipitation during "deglaciations" occurred almost synchronously with see level raise caused by the Northern Hemisphere ice sheets retreat. The Vostok ice core data are not in accord with the idea that the West-Antarctica ice sheet could collapse during marine isotope stage 11 (410-370 kyr BP), but instead support a substantial stability of Antarctic ice sheet in the changing climate.

Based on the results of the detailed snow-pit studies we reconstructed local climate variations in the central Antarctica (Vostok Station) during the last 200 years. The obtained time series of both accumulation and air temperature revealed quasi-periodical (about 50 years) variations, which could be related to the changes of cyclonic activity in the Southern Hemisphere. Importantly, the data do not show significant climatic trends in the central Antarctica over the past two centuries.