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Summary: 51
Introduction
Atmospheric noble gases dissolved in lake water can be viewed
as proxies for the temperature, salinity, and atmospheric pressure
prevailing during their equilibration at the lake surface. This is
because in situ noble gas concentrations in a given water parcel
in a lake correspond closely to the atmospheric equilibrium con-
centrations computed from the water temperature, salinity, and
atmospheric pressure at the time when the water parcel was last
in contact with the atmosphere (Aeschbach-Hertig et al. 1999;
Peeters et al. 2000). Thus, the distribution of noble gases in a lake
is related to internal mixing conditions, which in turn depend on
the prevailing meteorological conditions. For a recent review of
the atmospheric noble gas tracer methodology in aquatic sys-
tems, see Stute and Schlosser (2000) and Kipfer et al. (2002).
The noble gas concentrations just above the sediment/
water interface can be expected to be archived in the lake sed-
iment, because during sedimentation part of the overlying
water is incorporated into the sediment and is stored in its
pore space. The noble gases dissolved in sediment porewater
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