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Abstract The metal elements in alpine ice can provide historical information about natural mineral dust and anthropogenic pollutant emissions. To determine how the Fe concentration and flux variations relate to natural sandstorms and anthropogenic emissions from 1956 to 2004 A.D., Fe, Al, Pb and other element records were measured in a shallow ice core from the Miaoergou Glacier in East Tienshan, central Asia. The results indicate that the dissolved Fe (DFe) and total dissolved Fe (TDFe) peaks are well correlated with sandstorms from the surrounding Taklamakan Desert since at least 1956 A.D. The concentrations and fluxes of Pb show continuously increasing trends since 1995 A.D. due to the accelerating progress of the industrial revolution in China during this period, while the DFe and TDFe concentrations and the fractional Fe solubility exhibit no significant variations during this period. These results provide an ideal opportunity to investigate the effects of the natural Fe record in an arid region. Graphical abstract Image 1 Highlights • High-resolution Fe records from 1956 to 2004 were identified in the Miaoergou ice core. • The Pb element increased with anthropogenic industrial activities. • The fraction of soluble Fe varied with sandstorms from 1956 to 1990s. [ABSTRACT FROM AUTHOR]

The compositions of Sr and Pb isotopes in the soluble and insoluble dust in six samples from the Miaoergou ice core in eastern Tienshan, China, were measured. The six samples were dated from top to bottom as follows: 2000 AD, 1991 AD, 1983 AD, 1977 AD, 1962 AD and 1958 AD. The 87 Sr/ 86 Sr ratios in the soluble fraction ranged from 0.709984 to 0.711031. The isotopic ratios of Pb in the soluble and insoluble dust were between 17.962–18.182 and 18.198–18.409 for 206 Pb/ 207 Pb; 15.540–15.606 and 15.560–15.581 for 208 Pb/ 207 Pb; and 37.994–38.173 and 38.179–38.384 for 208 Pb/ 204 Pb, respectively. These isotopic results for insoluble dust allowed us to document the origins of the dust in the Miaoergou Glacier in eastern Tienshan. The major sources of the natural aeolian deposits were the Taklamakan and Gobi deserts. Natural and anthropogenic Pb sources were assessed using a simple ternary model in which deserts, lead ore and coal served as the primary sources of insoluble dust. Lead ore, coal combustion, and the use of leaded gasoline in the surrounding area may represent additional anthropogenic sources of soluble dust. Thus, anthropogenic sources could be further investigated by using the dust-free soluble fractions. The Pb concentration and Pb isotopic compositions from the High Asia ice cores provided distinct evidence of the positive influences of anthropogenic factors associated with industrial development and the prevailing atmospheric circulation patterns in these regions. [ABSTRACT FROM AUTHOR]

An ice core was extracted from Miaoergou Glacier, east Tien Shan, China. Concentrations of the rare earth elements (REEs) and Sr–Nd isotopic ratios were measured in insoluble dust sampled from the core. The ratios of REEs in insoluble dust were found to have characteristics typical of aeolian deposition, similar to those of sand and loess from Taklamakan. This suggests that the Taklamakan Desert might be an important source of dust reaching the Miaoergou Glacier. Sr ( 87 Sr/ 86 Sr average 0.718014 and range 0.717025 to 0.718958) and Nd (ε Nd (0) average − 9.1 and range − 9.5 to − 8.5) isotopic compositions in insoluble dust are similar to those of desert sand from Taklamakan and Gobi, suggesting that the Gobi Desert may be another major aeolian source for Miaoergou Glacier. Our results can be compared with Sr–Nd isotopic ratios from Greenland snow and ice, further demonstrating how the dust from Asian deserts contributes a high proportion of aeolian dust in the Greenland region. [ABSTRACT FROM AUTHOR]

In this study, a shallow ice core (12.5 m, called LGB) was drilled at the Lambert Glacial Basin, East Antarctica. The major ion and metal elements were measured at 5–6 cm resolution in this shallow core, which covered the period 1990–2017. Therefore, an annual-resolution record of iron (Fe) concentrations and fluxes were reconstructed in this shallow ice core. Although the Fe data is comparable to previous results, our results emphasized that much more dissolved Fe (DFe) from the Cerro Hudson volcanic event (August 1991) was transported to the East Antarctic ice sheet, in comparison with the Pinatubo volcanic event (June 1991). The aeolian dust may be the primary DFe source during 1990–2017. In particular, the DFe variations may be affected by the biomass burning emissions in two periods (1990–1998 and 2014–2017). While total dissolved Fe (TDFe) variations were controlled by the climatic conditions since 2000 because of the temperature (δ18O) decreasing at East Antarctica. These Fe data will be useful to assess the modern bioavailable Fe release for the Antarctica ice sheet. • High resolution DFe (TDFe) data was collected from an East Antarctic shallow core. • The eruption events can provide plenty DFe and stored in Antarctica ice sheet. • Fe variations during 1990–2017 were controlled by natural climatic characteristics. [ABSTRACT FROM AUTHOR]