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| Titel |
Stable isotope variability in snow on an alpine glacier in Switzerland |
| VerfasserIn |
M. S. Town, V. P. Walden, H. Huwald, C. W. Higgins, D. Nadeau, S. Simoni, M. B. Parlange |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250029839
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| Zusammenfassung |
| Understanding the variability and post-depositional modification of water stable isotopes in
snow is of significant importance to paleoclimatology and alpine hydrology. There
is modeling evidence that the stable isotopic content of near-surface snow may
change as a result of deposition of atmospheric water vapor within the snow. These
findings have yet to be confirmed by observation. In addition, ground water and
river sources are often identified by their isotopic signature. Understanding the
source of the isotopic signature, the recently fallen snow, and how that signature
changes just after deposition may aid alpine watershed assessments. Here we present
meteorological, hydrologic, and isotopic data taken from Feb-Mar 2008 on a high
altitude alpine glacier, the Plaine Morte, in Switzerland. The Plaine Morte is large
plateau (8 km2), surrounded by a 300 m ridge line. We use this site (2775 m a.s.l.,
46.3oN, 7.5oE) as a laboratory for understanding the effect of meteorology on the
isotopic signature of the near-surface snow. The snow surface of the Plaine Morte is
isotopically uniform, except in areas that collect large amounts of drift from neighboring
ridges and slopes. We present δ18O profiles down to 1.2 m for five different days.
While the spatial variability of δ18O of the surface snow is less than 1 per mil,
the variability of the profiles is on the order of 15-20 per mil. We investigate the
relationship between the δ18O profiles and the available meteorological data to look for
evidence of post-depositional modification due to the influence of the atmosphere. |
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