Isotope Stratification in High Mountain Glaciers: Examples from the Peruvian Andes and Himalaya

Abstract

Abstract18O and deuterium content was measured in snow and ice samples collected from two crevasses on temperate glaciers high in the Andes and in the Himalaya. The results show that, due to intense exposure to sun, a significant part of the annual accumulation of snow is removed by melting and sublimation, the latter being predominant. There is strong empirical evidence that in natural conditions which are characteristic of both the glaciers studied sublimation of the snow cover can be approximated by the thermodynamic equilibrium process. The short-term fluctuations, though slightly moderated, and longer-term variations can still be observed in the deeper parts of the glaciers in spite of firnification of the snow.