Kinetische Isotopentrennung bei der Verdampfung von Wasser

Diffusivity fractionations of HO/HO and HO/HO in air and their implications for isotope hydrology

“…In our design we followed the approach of previous studies, 7,9,13 ). It should be mentioned that the above design was developed after preliminary tests that showed that the resulting isotope fractionation was sensitive to whether the air flow was directed towards or away from the water surface, on the presence or absence of diffusing glass wool and on relative humidity.…”

Gas Exchange and Evaporation Studies in a Circular Wind Tunnel, Continuous Radon-222 Measurements at Sea, and Tritium/Helium-3 Measurements in a Lake

“…Extrapolation to air saturated with moisture gives the equilibrium fractionation factor of water in equilibrium with its vapour, while the additional fractionation is kinetic and due to the different molecular diffusion resistances for 820 and 820-18 molecules in the viscous gas sublayer adjacent to the liquid interface. The ratio D(820)/D(820-18) of the diffusion constants is known [5,6] to be 1.030 which means that the maximum possible depletion of 0-18 during evaporation of water into dry air is £(0-18) = -10-30 =-40%0 and would be reached if the vapour had to diffuse through a stagnant air layer into a well mixed dry space. The kinetic 0-18 depletion in the vapour which is observed here, however, is (if extrapolated to zero air moisture) only about -14%, i.e.…”

The Cherty Rock, Elgin: A petrographic and isotopic study of a Permo‐Triassic calcrete

“…Oxygen isotopes in meteoric waters are related to climate, particularly to mean annual temperature, but are also related to altitude and latitude (Gat 1980). Enrichment of '*O relative to 0 occurs during initial evaporation from free-standing bodies of water (Enhalt and Knott 1965).…”