Enrichment of surface ice stable water isotope ratios following sublimation
OA Version
Citation
Abstract
Stable isotopes of water preserved in glaciers and icesheets have revolutionized our
understanding of terrestrial paleoclimate. Post-deposition alteration of the stable water
isotope ratios in snow and ice can obscure the original meteoric signal, therefore altering
the interpretation of δ18O and δD as records of paleo-temperatures in ice. The effects
of sublimation on δ18O and δD are not well-understood for massive (non-snow) ice and
have been largely overlooked, particularly within the experimental literature. We present
results from a series of environmental chamber experiments investigating alteration of the
in-situ signal following sublimation. Our data suggest that sublimation enriches the ice
remaining after sublimation in 18O and D. This is observed both in surface ice and in the
signal of the ice at depth. These results could have important implications for studies
utilizing surface ice δ18O and δD for reconstructions of paleoclimate.