Record of δ$^{18}$O and $^{17}$O-excess in ice from Vostok Antarctica during the last 150,000 years
Résumé
We measured δ$^{17}$O and $^{18}$O in recent Antarctic snow and down the Vostok ice core and calculated the excess of $^{17}$O with respect to VSMOW. The magnitude of the $^{17}$O excess in the Holocene and the last interglacial is ~45 per meg, and it remains constant in a transect from the coast to the continental interior. Analysis of the transect data shows that the $^{17}$O-excess is not sensitive to temperature variations over the continent. There are significant shifts in $^{17}$O-excess from low values in glacial to high values in interglacial times. The observed shifts suggest higher normalized relative humidity and/or wind speeds over the source oceanic regions in glacial times.
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