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Antarctic trace element records could provide important insights into the impact of human activities on the environment over the past few centuries. In this study, we investigated the atmospheric concentrations of 14 representative heavy metals (Al, As, Cd, Co, Cu, Fe, K, Mg, Mn, Pb, Sb, Sr, Tl and V) from 174 samples collected in a 4-m snow pit at Dome Argus (Dome A) on the East Antarctic Plateau, covering the period from 1950 to 2016 A.D. We found great variability in the annual concentration of all metals. The crustal enrichment factors suggest that the concentrations of some heavy metals (Cd, Sb, Cu, As and Pb) were likely influenced by anthropogenic activities in recent decades. An analysis of source regions suggests that heavy metal pollution at Dome A was largely caused by human activities in Australia and South America (e.g. mining production, leaded gasoline). Based on the relationship between the trace elements fluxes and sea ice concentration (SIC), sea surface temperature (SST) and annual mean air temperature at 2 m above the ground (T 2m), our analysis shows that deposition and transport of atmospheric aerosol at Dome A were influenced by circum-Antarctic atmospheric circulations. Image 1 • First high-resolution trace elements were determined at Dome A, on the East Antarctic Plateau. • Anthropogenic elements (Cd, Sb, Cu, As and Pb) likely come from South America. • Element fluxes are affected by sea ice, sea surface and air temperature. [ABSTRACT FROM AUTHOR]

174 snow samples were collected from a 4.5 m snow pit at Dome Argus (Dome A), East Antarctica, during the 2015–2016 austral summer. They covered a period between 1950 and 2016. These samples were measured for iron (Fe) concentrations by the inductively coupled plasma mass spectrometry (ICP-MS). Both the total dissolvable Fe (TDFe) and dissolved Fe (DFe) were measured in order to evaluate the fractional Fe solubility (FFS), an important variable to determine the Fe availability for biological activities. The results show an average TDFe flux of 0.019 mg m−2 a−1 and DFe flux of 2.254 × 10−3 mg m−2 a−1 at Dome A. The mean FFS of 7.27% is consistent with previous studies on the Antarctic ice sheet. Based on the mean value of the TDFe fluxes from both the current and previous studies, the atmospheric TDFe flux in Antarctic modern snow was estimated at 19–140 × 10−3 mg m−2 a−1, potentially supporting 10.5–76.5 Tg C a−1 of primary production. This accounts about 1.21–8.80% of the annual primary production in the seasonal sea ice zone of Southern Ocean (SO), suggesting that atmospheric DFe is a minor component of Fe supply. • We sampled snow pit in Dome Argus of East Antarctica. • We depicted the variability of TDFe and DFe concentrations. • FFS and probable source of atmospheric iron were derived. • We evaluated atmospheric iron deposit flux in Antarctic ice sheet. [ABSTRACT FROM AUTHOR]