Grain-scale mechanisms influencing the elution of ions from snow

Columns containing synthetic, naturally- or laboratory-aged snow grains were washed with deionized distilled water and with a simulated precipitation solution to investigate both chemical fractionation and preferential ion elution. The resulting elution order and concentrations of Cl−, NO3− and SO42− were not influenced by chromatographic effects, indicating that snow grains do not possess selective affinity for inorganic anions. Fractionation and preferential chemical elution were strongly influenced by ion exclusion and rearrangement processes occurring during dry snow metamorphism, independent of melt-freeze cycles.