The changes in isotope composition and accumulation of snow at Vostok station, East Antarctica, over the past 200 years

Abstract

Abstract High-resolution records of isotope composition (δD) and accumulation of snow have been obtained from 10–12m deep snow pits dug in the vicinity of Vostok station during the 1979/80 and 1999/2000 Antarctic field seasons. We employ meteorological, balloon-sounding and snow-stake data to interpret the isotope record in terms of past temperature changes. Our reconstruction suggests that snow accumulation rate and the near-surface air temperature at Vostok have varied during the past 200 years between 15 and 30 kg m –2 a –1 , and between –56 and –55˚C, respectively, with a slight general tendency to increase from the past to the present. Both parameters reveal a 50 year periodicity that correlates with the Pacific Decadal Oscillation index, implying a climatic teleconnection between central Antarctica and the tropical Pacific.