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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)
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)
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)
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)
[1] Concentrations of noble gases, stable isotopes and 14 C in samples from the Continental Terminal groundwaters of Niger provide evidence for more humid and cooler climate phases in West Africa in the Holocene and the late Pleistocene. During humid phases, even within the Holocene, the soil temperature was up to 5.5°C cooler than today, which is partly(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)
, Vertical turbulent diffusion coefficients, upwelling velocities, and oxygen depletion rates are estimated by inverse modeling of the concentrations of CFC-ll (CCI 3 F), CFC-12 (CCI 2 F 2), JH, 3He, and dissolved oxygen for the southern, central, and northern basin of Lake Baikal. A model is developed that considers two regions in each basin of Lake(More)