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Full-Text Articles in Meteorology
Deuterium Excess And 17o-Excess Variability In Meteoric Water Across The Pacific Northwest, Usa, John Bershaw, Dougal Hansen, Andrew Schauer
Deuterium Excess And 17o-Excess Variability In Meteoric Water Across The Pacific Northwest, Usa, John Bershaw, Dougal Hansen, Andrew Schauer
Geology Faculty Publications and Presentations
High-precision triple oxygen isotope analysis of water has given rise to a novel second-order parameter, 17O-excess (often denoted as δ17O), which describes the deviation from a reference relationship between δ18O and δ17O. This tracer, like deuterium excess (d-excess), is affected by kinetic fractionation (diffusion) during phase changes within the hydrologic cycle. However, unlike d-excess, 17O-excess is present in paleowater proxy minerals and is not thought to vary significantly with temperature. This makes it a promising tool in paleoclimate research, particularly in relatively arid continental regions where traditional approaches have produced equivocal results. …
Controls On Deuterium Excess Across Asia, John Bershaw
Controls On Deuterium Excess Across Asia, John Bershaw
Geology Faculty Publications and Presentations
Deuterium excess (d-excess) is a second-order stable isotope parameter measured in meteoric water to understand both the source of precipitation and the evolution of moisture during transport. However, the interpretation of d-excess patterns in precipitation is often ambiguous, as changes in moisture source and processes during vapor transport both affect d-excess in non-unique ways. This is particularly true in Asia where continental moisture travels a long distance across diverse environments from unique moisture sources before falling as precipitation. Here, I analyzed published d-excess records from meteoric water throughout Asia to better characterize what influences d-excess values. I conclude that, (1) …