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Several studies have used the temperature dependence of gas solubilities in water to derive paleotemperatures from noble gases in groundwaters. We present a general method to infer environmental parameters from concentrations of dissolved atmospheric noble gases in water. Our approach incorporates statistical methods to quantify uncertainties of the deduced(More)
A unique data set of 50 years of monthly temperature profiles from Lake Zurich, a normally ice-free lake located on the Swiss Plateau, allowed the one-dimensional numerical k-␧ lake model ''SIMSTRAT'' to be calibrated (1948– 1957) and validated (1958–1997). Hindcasts of temperature profiles agree excellently with the measured data. Both interannual and(More)
We present elemental and isotopic measurements of noble gases (He, Ne, Ar, Kr, and Xe), oxygen and nitrogen of firn air from two sites. The first set of samples was taken in 1998 at the summit of the Devon Ice Cap in the eastern part of Devon Island. The second set was taken in 2001 at NGRIP location (North Greenland). He and Ne are heavily enriched(More)
Dissolved noble gases in groundwater are used to reconstruct paleotemperature, but also yield information about "excess air", a component of dissolved gases in excess of solubility equilibrium, derived from dissolution of trapped air in the ground. A good characterization of the excess air component is necessary not only to obtain reliable noble gas(More)
In order to quantify deep-water exchange in the Caspian Sea, the world's largest inland water body, water samples were analyzed for the transient tracers H, He, He, CFC-11, CFC-12 and atmospheric noble gases. Measurements of temperature, salinity (calculated from conductivity for the ionic composition of Caspian Sea water), and dissolved oxygen were(More)
—The interpretation of noble gas concentrations in groundwater with respect to recharge temperature and fractionated excess gas leads to different results on paleo-climatic conditions and on residence times depending on the choice of the gas partitioning model. Two fractionation models for the gas excess are in use, one assuming partial re-equilibration of(More)
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 concentrations computed from the water(More)
The (Lower) Lake of Zurich provides an ideal system for studying the long-term impact of environmental change on deep-water hypoxia because of its sensitivity to climatic forcing, its history of eutrophication and subsequent oligotrophication, and the quality and length of its data set. Based on 39 years (1972-2010) of measured profiles of temperature,(More)
The concept of potential density, introduced by oceanographers to describe the vertical stability of a water column, may be inadequate if the water temperature is close to the temperature of maximum density, Tmd, where the thermal expansion coefficient changes its sign. Because r,, decreases with increasing pressure potential density especially fails to(More)