Post-depositional changes in snow isotope content: preliminary results of laboratory experiments
A. A. Ekaykin1,2, T. Hondoh1, V. Y. Lipenkov2, and A. Miyamoto11Institute of Low Temperature Sciences, Hokkaido University, 060-0819 Sapporo, Japan 2Arctic and Antarctic Research Institute, 199397 St. Petersburg, Russia
Received: 03 Sep 2009 – Accepted for review: 08 Sep 2009 – Discussion started: 08 Oct 2009
Abstract. Isotopic content of the snow and firn thickness is assumed to be altered significantly due to the post-depositional (PD) mass- and isotope exchange with the atmospheric water vapor. If so, these effects should be accounted for in the ice core-based isotope-temperature paleo-reconstructions. In order to study the intensity of the PD processes we set up a series of laboratory experiments. In this paper we describe in detail the experimental technique and briefly overview preliminary results. It is shown that the PD modifications in the upper layer of snow thickness are noticeably strong even under such a low temperature as −35°C (the value typical for the Central Antarctic summer). It is demonstrated that the PD isotopic changes in snow can be approximated as a linear function of the relative mass loss due to snow sublimation. Possible applications for improving the isotope-temperature paleo-reconstructions are shortly discussed.
Ekaykin, A. A., Hondoh, T., Lipenkov, V. Y., and Miyamoto, A.: Post-depositional changes in snow isotope content: preliminary results of laboratory experiments, Clim. Past Discuss., 5, 2239-2267, doi:10.5194/cpd-5-2239-2009, 2009.