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Showing 1 to 11 of 11 for “"deuterium excess"”.
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Temporal Variations of delta 2 H, delta 18 O and Deuterium Excess in Atmospheric Moisture and Improvements in the CO 2 -H 2 O Equilibration Technique for 18 O/ 16 O Isotope Ratio Analysis
… not for monthly means. This study focuses on the deuterium excess in water vapour, d(vap), such as its difference to the mostly analysed deuterium excess in precipitation, d(prec). Both d’s are assumed to be controlled primarily by the moisture deficit above the ocean, the major source of …
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Evaluation of Paleo-climate for the Boise Area, Idaho, from the last Glacial Maximum to the Present Based on delta 2H and delta 18O Groundwater Composition
… and defined single slopes of 6.94 and 8. Deuterium excess values (d) were found for each system for each linear regression method. Relative differences of the deuterium excess value assuming the two single slope methods were similar. Changes in moisture source humidity and temperature, and …
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Innovative water tracers and water isotopes enhance Antarctic research with climate models
… information to examine the interpretation of deuterium excess in Antarctic ice cores. I focused on modelled relationships between deuterium excess and moisture source properties. The logarithmic definition of deuterium excess dln is found to be superior to the linear definition dxs in …
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Towards a coupled δ18O sugar and δ2H n-alkane approach in paleoclimate research
… water were reconstructed and used to assess the deuterium excess of leaf water. The calculated deuterium excess proved to be a suitable proxy for RH, revealing a systematic trend towards more negative values in the southern, more arid part of the transect. Using a Péclet modified Craig-Gordon …
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DIURNAL VARIATION OF WATER VAPOR ISOTOPOLOGUES ON THE CHAJNANTOR PLATEAU DURING THE AUSTRAL SPRING
… in δ18O, 71‰ increase in δD, and 23‰ decrease in deuterium excess on the Plateau. This significant diurnal variation is a result of the mixing between dry, upper tropospheric air (dry end-member) and a small contribution (9-25%) of a continental (δD < -120‰) source of moisture (wet end-member). …
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ISOTOPIC CONSTRAINTS ON ATMOSPHERIC MOISTURE TRANSPORT PROCESSES IN SOUTH AMERICA
… of isotopic ratios, mixing ratios, and deuterium-excess (i.e. d-excess = δD – (8*δ18O)) indicate that condensation under ice supersaturated conditions and mixing with moister air play important roles in controlling moisture transport to the hyperarid Chajnantor Plateau.
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Variations in the stable isotope compositions of water vapor and precipitation in New Mexico : links to synoptic-scale weather
… is downwind of vigorous convective activity. The deuterium excess (d) of Albuquerque's vapor samples are remarkably consistent, especially when compared to reported values of d from other studies of water vapor. Our water vapor samples plot parallel to the Global Meteoric Water Line with an …
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Impact of Isotopic Heterogeneity in Shallow Systems on Modeling of Stormflow Generation
… of evaporative fractionation; instead, the high deuterium-excess values suggest considerable exchange with re-evaporated waters. A 490-m^2 artificial catchment in China was used to investigate the effects of temporal variations in rain composition, and temporal and spatial variations in dominant …
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Precipitation amount, altitude, and moisture trajectory effects on the stable isotopic composition of precipitation in the Galapagos Islands
… between moisture source area and δ18Op or deuterium excess is observed in our samples. We also find a lack of a predictable seasonal shift in moisture sources which explains the very small seasonal variation in δ18Op. Daily δ18Op near sea level was significantly correlated with …
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Effects of water balance, decomposition of organic matter and photosynthesis on the chemistry and the carbon cycle in the Upper St.Lawrence River (Canada).
… then added to atmospheric vapor and produces a deuterium excess of 11.8 +/- 1.4‰ in local rain at Cornwall that indicates admixture of evaporated Great Lakes water to the local precipitation. Precipitation over the Great Lakes catchment area contributes 3.9% of Mg2+ and 31.2% of SO42- to …
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Evolution and degradation pathways of landfill leachate DOC and detection of groundwater landfill-leachate contamination using compound-specific isotope analysis
… of young leachate at LPS (-16.9 ‰). (2) Deuterium excess provides a robust indicator of overall methane production, showing greater CH4 production in the younger parts of landfill than the older parts. The CO2 reduction pathway (alpha13C CO2-CH4=1.06) dominants at the younger landfill, …