ACID IONS AT TRIPLE JUNCTION OF ANTARCTIC ICE OBSERVED BY RAMAN-SCATTERING

We measured the Raman spectra of the junctions where three crystal gra ins met (triple-junctions) in polycrystalline ice from two Antarctic s ites (Nansen ice and South Yamato ice) in order to obtain direct evide nce that sulfuric and nitric acids are present as liquid at the triple -junctions. We found that Raman spectra of Nansen ice have a peak (105 0 cm(-1)) of HSO4- and NO3- in sulfuric and nitric acid solutions when the measured temperatures of the ice are -8 similar to-35 degrees C. Thus, sulfuric and nitric acids dissociate to HSO4- and NO3- at the tr iple-junctions of Nansen ice. Raman spectra of South Yamato ice have a peak (980 cm(-1))of SO42- in sulfuric acid solution when the measured temperatures of the ice are -8 similar to-20 degrees C. Thus, sulfuri c acid dissociates to SO42- at the triple-junctions of South Yamato ic e. The results showed that aqueous solutions of the acids exist at Ant arctic ice-sheet temperatures.