Optimization of a Picarro L2140-i cavity ring-down spectrometer for routine measurement of triple oxygen isotope ratios in meteoric waters

Atmospheric measurement techniques, Journal Year: 2023, Volume and Issue: 16(6), P. 1663 - 1682

Published: March 29, 2023

Abstract. The demanding precision of triple oxygen isotope (Δ17O) analyses in water has restricted their measurement to dual-inlet mass spectrometry until the recent development commercially available infrared laser analyzers. Laser-based measurements ratios are now increasingly performed by laboratories seeking better constrain source and history meteoric waters. However, practice, these subject large analytical errors that remain poorly documented scientific literature instrument manufacturers, which can effectively restrict confident application Δ17O settings where variations relatively (∼ 25–60 per meg). We present our operating method a Picarro L2140-i cavity ring-down spectrometer (CRDS) during analysis low-latitude rainwater confidently resolving daily (differences ∼ 10–20 meg) was desired. Our approach optimized over 3 years uses combination published best practices plus additional steps combat spectral contamination trace amounts dissolved organics, which, for Δ17O, emerges as much more substantial problem than previously documented, even pure rainwater. resolve extreme sensitivity organics through removal via Picarro's micro-combustion module, whose performance is evaluated each sequence using alcohol-spiked standards. While correction sample-to-sample memory instrumental drift significantly improves traditional metrics, corrections have only marginal impact (0–1 meg error reduction) on Δ17O. post-processing scheme analyzer's high-resolution data, δ2H (0.25 ‰ allows rich troubleshooting data processing compared default user-facing output. In addition competitive we report long-term, control standard root mean square 12 meg. Overall (Δ17O 6 meg, calculated averaging three replicates spread across distinct, independently calibrated sequences) comparable requires 6.3 h sample. demonstrate rainfall dataset from Uganda offer recommendations other efforts aim measure CRDS.

Language: Английский

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Toward a common methodological framework for the sampling, extraction, and isotopic analysis of water in the Critical Zone to study vegetation water use

Wiley Interdisciplinary Reviews Water, Journal Year: 2024, Volume and Issue: 11(4)

Published: March 5, 2024

Abstract The analysis of the stable isotopic composition hydrogen and oxygen in water samples from soils plants can help to identify sources vegetation uptake. This approach requires that heterogeneous nature plant soil matrices is carefully accounted for during experimental design, sample collection, extraction analyses. comparability shortcomings different methods extracting analyzing have been discussed specialized literature. Yet, despite insightful comparisons benchmarking methodologies laboratories worldwide, community still lacks a roadmap guide extraction, analyses, many practical issues potential users remain unresolved: example, which (soil or plant) pool(s) does extracted represent? These constitute hurdle implementation by newcomers. Here, we summarize discussions led framework COST Action WATSON (“WATer isotopeS critical zONe: groundwater recharge transpiration”—CA19120). We provide guidelines (1) sampling material analysis, (2) laboratory situ (3) measurements composition. highlight importance considering process chain as whole, design minimize biased estimates relative contribution conclude acknowledging some limitations this methodology advice on collection key environmental parameters prior article categorized under: Science Water > Hydrological Processes Environmental Change Extremes

Language: Английский

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On the urgent need for standardization in isotope‐based ecohydrological investigations

Hydrological Processes, Journal Year: 2022, Volume and Issue: 36(10)

Published: Sept. 12, 2022

Abstract Ecohydrological investigations commonly use the stable isotopes of water (hydrogen and oxygen) as conservative ecosystem tracers. This approach requires accessing analysing from plant soil matrices. Generally, there are six steps involved to retrieve hydrogen oxygen isotope values these matrices: (1) sampling, (2) sample storage transport, (3) extraction, (4) pre‐analysis processing, (5) isotopic analysis, (6) post‐processing correction. At each step, cumulative errors can be introduced which sum non‐trivial magnitudes. These impact subsequent interpretations about cycling partitioning through soil–plant‐atmosphere continuum. steps, multiple possible options select resulting in tens thousands combinations used by researchers go samples data. In a newly emerging field, so many create interpretive confusion major issues with data comparability. points need for development shared standardized approaches. Here we critically examine state process chain, reflecting on associated provide suggestions move our community towards standardization. Assessing this ‘process chain’ will help us see problem its entirety facilitate action agreed upon

Language: Английский

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The response and sensitivity of deuterium and 17O excess parameters in precipitation to hydroclimate processes

Earth-Science Reviews, Journal Year: 2023, Volume and Issue: 242, P. 104432 - 104432

Published: April 23, 2023

Language: Английский

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Cavity Ring-Down Spectroscopy Performance and Procedures for High-Throughput δ18O and δ2H Measurement in Water Using “Express” Mode

Applied Spectroscopy, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 2, 2025

Cavity ring-down spectroscopy (CRDS) is rapidly becoming an invaluable tool to measure hydrogen (δ²H) and oxygen (δ

Language: Английский

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Stable isotope patterns of German rivers with aspects on scales, continuity and network status

Isotopes in Environmental and Health Studies, Journal Year: 2022, Volume and Issue: 58(4-6), P. 363 - 379

Published: Oct. 11, 2022

In Germany, river monitoring for tritium started in the early 1970s. Today this network consists of 50 stations and includes stable isotopes. The isotope time series to end 2021 are at least four years some up 30 long. Daily water samples were collected during an extraordinary dry season from October 2018 until January 2019 six selected Rhine five Elbe basin. most dominating effects seasonal altitude effects, but also a continental effect is visible. isotopes indicate snow ice melt contributions Danube summer months consecutive dilution these signals by mixing with tributary rivers. Close coasts northern patterns reflect influence seawater tides. 2018/2019 surprisingly do not exhibit extreme changes rather trends enhanced groundwater contribution. Long-term continual data across scales important comparing identifying hydrological processes German basins different size mean catchment altitudes, highlight benefits co-organized national network.

Language: Английский

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Predicting the spatial distribution of stable isotopes in precipitation using a machine learning approach: a comparative assessment of random forest variants

GEM - International Journal on Geomathematics, Journal Year: 2023, Volume and Issue: 14(1)

Published: June 12, 2023

Abstract Stable isotopes of hydrogen and oxygen are important natural tracers with a wide variety environmental applications (e.g., the exploration water cycle, ecology food authenticity). The spatially explicit predictions their variations obtained through various interpolation techniques. In present work, classical random forest (RF) two its variants were applied. RF version employing buffer distance (RF sp ) applied to each month separately, while model was trained using all data year as categorical variables tg ). Their performance in predicting spatial variability precipitation stable isotope values for 2008–2017 across Europe compared. addition, comparison made publicly available alternative machine learning which employs extreme gradient boosting. Input retrieved from Global Network Isotopes Precipitation (GNIP; no. stations: 144) other national datasets (no. 127). Comparisons on basis absolute differences, median, mean error Lin’s concordance correlation coefficient. All capable reproducing overall trends seasonal patterns over time measured at chosen validation site Europe. most predictors latitude case RF, meteorological (vapor pressure, saturation vapor temperature) models. Diurnal temperature range had weakest predictive power every case. conclusion, it may be stated that merged dataset, combining GNIP datasets, yielded smallest 1.345‰) highest coefficient (0.987), boosting (based only data) 1.354‰, 0.984, although produced lowers median value (1.113‰), 1.124‰. striking systematic bias observed summer season northern stations; this, however, diminished 2014 onward, point after stations beyond 55° N training set.

Language: Английский

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The CISE-LOCEAN seawater isotopic database (1998–2021)

Earth system science data, Journal Year: 2022, Volume and Issue: 14(6), P. 2721 - 2735

Published: June 10, 2022

Abstract. The characteristics of the CISE-LOCEAN seawater isotope dataset (δ18O, δ2H, referred to as δD) are presented (https://doi.org/10.17882/71186; Waterisotopes-CISE-LOCEAN, 2021). This covers time period from 1998 2021 and currently includes close 8000 data entries, all with δ18O, three-quarters them also δD, associated a date stamp, space usually salinity measurement. Until 2010, samples were analyzed by isotopic ratio mass spectrometry since then mostly cavity ring-down spectroscopy (CRDS). Instrumental uncertainty in this is low 0.03 ‰ for δ18O 0.15 δD. An additional related composition in-house standards that used convert Vienna Standard Mean Ocean Water (VSMOW) scale. Different comparisons suggest 2010 latter have remained within at most 0.20 Therefore, combining two uncertainties suggests standard deviation 0.05 0.25 For some samples, we find there has been evaporation during collection storage, requiring adjustment produced CRDS, based on d-excess (δD − 8×δ18O). adds an respective roughly 0.10 issue conservation certainly strong source quality loss parts database, “small” effects may undetected. internal consistency database can be tested subsets when series obtained (such southern Indian or North Atlantic subpolar gyre). These overall spatially (for cruise) temporally (over year) averaged less than However, 18 duplicate other laboratories datasets intermediate deep ocean larger scatter. When averaging done difference 0.082 error 0.016 ‰. Such average expected due adjustments applied LOCEAN saline water either CRDS (IRMS), but scatter found care needed merging different laboratories. Examples surface gyre illustrate temporal changes detected carefully validated dataset.

Language: Английский

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The role of cave ventilation in the triple oxygen and hydrogen isotope composition of condensation waters in Altamira Cave, northern Spain

Journal of Hydrology, Journal Year: 2022, Volume and Issue: 606, P. 127416 - 127416

Published: Jan. 7, 2022

Language: Английский

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Balancing precision and throughput of δ17O and Δ’17O analysis of natural waters by Cavity Ringdown Spectroscopy

MethodsX, Journal Year: 2023, Volume and Issue: 10, P. 102150 - 102150

Published: Jan. 1, 2023

δ17O and Δ'17O are emerging tracers increasingly used in isotope hydrology, climatology, biochemistry. Differentiating small relative abundance changes the rare 17O from strong covariance with 18O imposes ultra-high precision requirements for this analysis. Measurements of by Cavity Ringdown Spectroscopy (CRDS) attractive due to ease sample preparation, automated throughput, avoidance chemical conversions needed isotope-ratio mass spectrometry. However, CRDS approach requires trade-offs measurement uncertainty. In protocol document, we present following:•New analytical procedures a software tool conducting measurements CRDS.•Outline robust uncertainty framework determinations.•Description performance optimizing instrumental stability, accuracy.

Language: Английский

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