Abstract:

We performed a comparison analysis of the variations in Mercury (Hg) concentrations and the precipitation proxies ( e. g., ¹⁸O values and ¹⁰Be concentrations) in the Dome C ice core. The results showed that there were significant correlations between Hg and δ¹⁸O values, ¹⁰Be concentrations, indicating that the accumulation rate in Dome C is one of the key factors controlling the variations of Hg concentrations in the past 34 ,000 years, and implying that Hg concentrations in ice core can be used as another reliable proxy of precipitation rate in Antarctica. Based upon the high-resolution δ¹⁸O values, we estimated the variations in mercury deposition flux to Antarctica over the past 34,000 years. The highest mercury deposition flux is about 3.80 pg cm^-2 yr^-1 during the Last Glacial Maxium (LGM) as high as 3.5 times of the mercury deposition flux ( about 1.08 pg cm^-2 yr^-1) in Holocene due to the fluctuations in natural mercury emissions such as the oceanic biological emissions.

Key words: mercury deposition flux, precipitation rate, LGM, Holocene, Antarctic Dome C ice core