Springtime peaks of trace metals in Antarctic snow

Drifting snow samples were collected at Asuka Station (71 degrees 32'S, 24 degrees 08'E, 930 m above sea level) over a period from July to December 1991; 36 elements (including Na, Mg, K, Ca, Fe, Al, Li, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, Se, Rb, Sr, Cd, Pb, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Th) in snow were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS) by direct sample introduction. Concentrations of Cl-, NO3-, and SO(4)2- in the snow were also determined by ion chromatography. In late September to early October, there was a pronounced peak concentration of most of the elements together with non-sea salt sulfate. Enrichment factor analyses suggest that Na, Mg, Ca, K, and Sr are of marine origin and Al, Fe, Mn, Rb, Cr, Ni, Ga, V, and all the rare earth elements are of crustal origins. Volcanic eruption of Mt. Pinatubo (June 1991) and Mt. Hudson (August 1991) could be the reason for the precipitation of Pb, Cd, Cu, Zn, and Se together with non-sea salt sulfates in the austral spring at Asuka Station.