| Summary: | This thesis presents a sub-seasonally resolved, decade long record of snow pack chemistry from Evans Piedmont Glacier (EPG), southern Victoria Land coast, Antarctica. Snow chemistry measurements were made at ca. 20 analyses per year for stable isotope ratios [delta to the power of 18]O and [delta]D, major ions Ca+, Cl-, K+, Mg+, MS-, Na+, NO3-, SO42- by ion chromatography (IC), and major and trace element chemistry by inductively coupled plasma mass spectrometry (ICP-MS). Na, Mg, Al, Fe, Mn and Ba were measured by ICP-MS using a hydrogen flushed collision cell to reduce the formation of polyatomic ion interferences, whereas Ti, V, Cr, Ni, Cu, Zn, As, Rb, Sr, Y, Zr, Sb, Cs, Ba, La, Ce, Pb, Bi, Th and U were measured in non-collision cell mode to increase count sensitivity. ICP-MS analytical precision is typically 5 to 10 % (2 rsd) that is two orders of magnitude at minimum below natural variability (e.g. samples range between Na = 10 to 18031 ppb and Al = 5 to 3856 ppb). The presence of undigested mineral dusts in weakly acidified samples, however, complicates the measurement of elemental concentrations in snow samples by randomly entering the ICP-MS. Despite this, the range of sample concentrations (Zr = 3.0 to 5630 ppb) is still orders of magnitude higher than sample reproducibility. The dominant source regions of element chemistry transported to EPG snow are identified as marine (Na, Mg, SO4, Cl, K, As and Sr) and terrestrial derived aerosol (Al, Mn, Fe, Ba, Ti, V, Ni, Cr, Zn, Rb, Y, Zr, Cd, Sb, Cs, Ba, La, Ce, Pb, Th and U), with minor contributions from anthropogenic (V, Cr, Ni, Cu, Zn, As, Sb and Pb) and volcanic emissions (Bi, SO4 and K). This is based on both elemental ratio modelling and ICP-MS time resolved analysis that identifies elements present in particulate form (mineral dusts). EPG snow chemistry is related to measured meteorological conditions at nearby Cape Ross. Winter maxima of elemental concentrations is consistent with maximum winter wind speed and low precipitation rates. Furthermore, ...
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