Panoply - Ice

Measurement of δ18O of liquid water and ice.

2015-06-08T11:47:41+00:00

Isotope ratio mass spectrometer Finningan MAT252 coupled to an equilibration bench

Description of the instrument:

Water samples (3mL) are equilibrated for 8 hours with CO2. The gas is then introduced in the mass spectrometer in dual inlet mode. Each sample is measured with respect to a laboratory standard for 15 min.

Generally speaking, in a mass spectrometer, the molecules are ionized in the source, accelerated in an electric field, and deviated depending on the mass to charge ratio by a magnetic field. Three faraday cages are placed at the outlet, and are aligned with mass 44, 45, 46 (for CO2).

Principle of the analysis:

http://www.thermo.com.cn/Resources/200802/File_28763.pdf

Type of analysis performed on this instrument:

This instrument is dedicated to the routine analysis of the oxygen isotopic composition (¹⁸O) of natural waters.

Analytical uncertainty: 2 = 0.05‰ for ¹⁸O

Contacts :

Bénédicte Minster

Measurement of δ18O and δ2H of liquid water and ice

2015-07-27T12:04:28+00:00

Laser spectrometer for water isotope measurements Picarro (L2130-i)

Description of the instrument:

This analyzer uses Cavity Ringdown Spectroscopy (CRDS) to quantify spectral features of gas phase molecules (H₂¹⁶O, H₂¹⁸O and HD¹⁶O) in an optical cavity.

Samples are automatically injected (2 microliters) in a vaporization module at 110°C before they are sent to the laser cavity. The measurement time for each sample is 9 minutes.

Principle of the analysis:

https://www.picarro.com/products/l2130i_isotope_and_gas_concentration_analyzer

Type of analysis performed on this instrument:

This instrument is dedicated to the routine analysis of the oxygen isotopic composition (¹⁸O and D) of natural waters.

Analytical precision :

1 = 0.2‰ for ¹⁸O

1 = 0.7‰ for D

Contacts :

Bénédicte Minster

Measurement of δ18O, δ17O and δ2H of liquid water and ice.

2015-07-27T12:58:22+00:00

Laser spectrometer for water isotope measurements including 17O-excess Picarro (L2140-i)

Description of the instrument:

This analyzer uses Cavity Ringdown Spectroscopy (CRDS) to quantify spectral features of gas phase molecules (H₂¹⁶O, H₂¹⁸O H₂¹⁷O and HD¹⁶O) in an optical cavity.

Samples are automatically injected (2 microliters) in a vaporization module at 110°C before they are sent to the laser cavity. The measurement time for each sample is 9 minutes, and several hours for the combined analysis of ¹⁷O – ¹⁸O.

Principle of the analysis:

https://www.picarro.com/isotope_analyzers/h2o_isotopes_liquid_and_vapor

Type of analysis performed on this instrument:

This instrument is dedicated to the routine analysis of the oxygen isotopic composition (¹⁸O, ¹⁷O and D) of natural waters.

Analytical precision:

1 = 0.2‰ for ¹⁸O

1 = 0.7‰ for D

1 = 10 ppm for ¹⁷O-excess

Contacts:

Frédéric Prié

Analyzes of major cations and metallic elements concentrations in water and sediments or rocks

2015-12-15T08:32:01+00:00

Agilent Technologies AAS 240 FS and GTA 120

Flame or Graphite Furnace Atomic Absorption Spectrometer to analyze cation concentrations (Al, As, Ba, Ca, Cr, Co, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Pt, Sb, Sn, Sr, Zn)

Description of the instrument

The Atomic Absorption Spectrometer (Agilent Technologies AAS 240 FS and GTA 120) can measure the concentrations of many elements. Depending on the concentrations of the solutions, it can be used in flame mode or in graphite furnace mode. It is equipped with automatic diluters (flame/oven) and autosamplers (flame/oven).

Principle of analysis

A liquid sample is injected as a mist into a flame (in flame mode) or a drop is placed in a graphite furnace (in graphite furnace mode). The heat vaporizes the elements contained in the sample and excites their atoms. These disrupt a light signal by reducing its intensity (absorption) or by emitting photons (emission). The light emitted by a hollow cathode lamp(s) or by the electrons of the excited atoms is sent via a set of mirrors and a crystal lattice to a detector which performs an optical measurement of the signal compared to a signal of undisturbed reference. The difference in light intensity is proportional to the concentration of the element in the solution. Calibration is done by injecting a standard solution to obtain the appropriate range. See principle of measurement here: http://spin.mines-stetienne.fr/sites/default/files/specatom.pdf

Analyzes carried out on the instrument

Major cations (Ca, Mg, Na and K) between 0.05 and 100 ppm in flame with an accuracy of +/- 5%;
Metals (Al, As, Ba, Cr, Co, Cu, Fe, Li, Mn, Mo, Ni, Pb, Pt, Sb, Sn, Sr, Zn) between 0.01 and 1000 ppm in flame depending on the elements and a few tens of ppt to a few tens of ppb in graphite furnace mode for some elements with an accuracy of +/- 5%;
Only liquid solutions (filtered and acidified) are analyzed but it is possible to measure solutions of acid attack on rocks, sediments or other solid samples.

Contacts

Gaël Monvoisin : + 33 (0)1.69.15.71.74 / gael.monvoisin@universite-paris-saclay.fr

Fundings

CNRS – INSU / University Paris-Sud : AAS flame Year 2010 – AAS graphite furnace Year 2012

Sub-millennial climate variability from high resolution water isotopes in the EDC ice core

2023-01-31T10:37:42+00:00

The EPICA Dome C (EDC) ice core provides the longest continuous climatic record covering the last 800,000 years (800 kyrs). The high resolution (11 cm) water isotopic record (δ¹⁸O and δD) is available for the EDC ice core and accounting for water isotopic diffusion provides a unique opportunity to investigate decadal to millennial variability during past glacial and interglacial periods. We present a continuous compilation of the EDC water isotopic record at a sample resolution of 11 cm that composed of 27,000 δ18O measurements and 7,920 δD measurements (covering respectively 94 % and 27 % of the whole EDC record), including both published and new measurements (2,900 for both δ¹⁸O and δD) over the last 800 kyrs on the EDC ice core. Here, we demonstrate that repeat water isotope measurements on the EDC ice core using different analytical methods on the same samples from different depth intervals are comparable within analytical uncertainty. From this comparison we combine EDC water isotope measurements to generate a high resolution (11 cm) data set over the past 800 kyrs (Figure 1). A frequency decomposition of the most complete δ¹⁸O record and a simple assessment of the possible influence of diffusion on the measured profile shows that the variability during glacial periods at multi-decadal to multi-centennial timescale is higher than variability of the interglacial periods. This analysis shows as well that during interglacial periods characterized by a temperature optimum at its beginning, the multi-centennial variability is the strongest over this temperature optimum.

Reference : Antoine Grisart, Mathieu Casado, Vasileios Gkinis, Bo Vinther, Philippe Naveau, Mathieu Vrac, Thomas Laepple, Bénédicte Minster, Frederic Prié, Barbara Stenni, Elise Fourré, Hans-Christian Steen Larsen, Jean Jouzel, Martin Werner, Katy Pol, Valérie Masson-Delmotte, Maria Hoerhold, Trevor Popp, Amaelle Landais., 2022. Sub-millennial climate variability from high resolution water isotopes in the EDC ice core. Clim. Past, 18, 2289–2301, https://doi.org/10.5194/cp-18-2289-2022.

The ST22 chronology for the Skytrain Ice Rise ice core – Part 2: An age model to the last interglacial and disturbed deep stratigraphy

2023-08-31T13:42:13+00:00

We present an age model for the 651 m deep ice core from Skytrain Ice Rise, situated inland of the Ronne Ice Shelf, Antarctica. The top 2000 years have previously been dated using age markers interpolated through annual layer counting. Below this, we align the Skytrain core to the AICC2012 age model using tie points in the ice and air phase, and we apply the Paleochrono program to obtain the best fit to the tie points and glaciological constraints. In the gas phase, ties are made using methane and, in critical sections, δ18Oair; in the ice phase ties are through 10Be across the Laschamps event and through ice chemistry related to long-range dust transport and deposition. This strategy provides a good outcome to about 108 ka (∼ 605 m). Beyond that there are signs of flow disturbance, with a section of ice probably repeated. Nonetheless values of CH4 and δ18Oair confirm that part of the last interglacial (LIG), from about 117–126 ka (617–627 m), is present and in chronological order. Below this there are clear signs of stratigraphic disturbance, with rapid oscillation of values in both the ice and gas phase at the base of the LIG section, below 628 m. Based on methane values, the warmest part of the LIG and the coldest part of the penultimate glacial are missing from our record. Ice below 631 m appears to be of age > 150 ka.

Figure : Age against depth for the Skytrain Ice Rise ice core. In the top panel, ice and air age are shown, along with the tie points we applied. The turquoise line shows the uncertainty on the ice age derived from Paleochrono, using the right hand y axis. The section with unreliable ages (605–617 m) is greyed out, and the uncertainties around this section are probably underestimated.

Reference: Mulvaney, R., Wolff, E. W., Grieman, M. M., Hoffmann, H. H., Humby, J. D., Nehrbass-Ahles, C., Rhodes, R. H., Rowell, I. F., Parrenin, F., Schmidely, L., Fischer, H., Stocker, T. F., Christl, M., Muscheler, R., Landais, A., and Prié, F., 2023. The ST22 chronology for the Skytrain Ice Rise ice core – Part 2: An age model to the last interglacial and disturbed deep stratigraphy. Clim. Past, 19, 851–864, https://doi.org/10.5194/cp-19-851-2023.

A 2000-year temperature reconstruction on the East Antarctic plateau from argon–nitrogen and water stable isotopes in the Aurora Basin North ice core

2023-08-31T13:48:08+00:00

The temperature of the Earth is one of the most important climate parameters. Proxy records of past climate changes, in particular temperature, represent a fundamental tool for exploring internal climate processes and natural climate forcings. Despite the excellent information provided by ice core records in Antarctica, the temperature variability of the past 2000 years is difficult to evaluate from the low-accumulation sites in the Antarctic continent interior. Here we present the results from the Aurora Basin North (ABN) ice core (71∘ S, 111∘ E, 2690 m a.s.l.) in the lower part of the East Antarctic plateau, where accumulation is substantially higher than other ice core drilling sites on the plateau, and provide unprecedented insight into East Antarctic past temperature variability. We reconstructed the temperature of the last 2000 years using two independent methods: the widely used water stable isotopes (δ18O) and by inverse modelling of borehole temperature and past temperature gradients estimated from the inert gas stable isotopes (δ40Ar and δ15N). This second reconstruction is based on three independent measurement types: borehole temperature, firn thickness, and firn temperature gradient. The δ18O temperature reconstruction supports stable temperature conditions within 1 ∘C over the past 2000 years, in agreement with other ice core δ18O records in the region. However, the gas and borehole temperature reconstruction suggests that surface conditions 2 ∘C cooler than average prevailed in the 1000–1400 CE period and supports a 20th century warming of 1 ∘C. A precipitation hiatus during cold periods could explain why water isotope temperature reconstruction underestimates the temperature changes. Both reconstructions arguably record climate in their own way, with a focus on atmospheric and hydrologic cycles for water isotopes, as opposed to surface temperature for gas isotopes and boreholes. This study demonstrates the importance of using a variety of sources for comprehensive paleoclimate reconstructions.

Figure : δ18O temperature and 15Nexcess temperature reconstructions (this study). Error shading is the same as in Fig. 9. (b) Southern Annual Mode (SAM) annual reconstruction (Dätwyler et al., 2018). The annual resolution of the SAM index is represented by thin lines, and thick lines are the 30-year average for both δ18O temperature and SAM; 15N-excess temperature has a resolution of about 45 years. Yellow shading highlights the 1000–1400 CE period during which the 15N-excess temperature is significantly colder, in phase with a positive SAM index.

Reference: Servettaz, A. P. M., Orsi, A. J., Curran, M. A. J., Moy, A. D., Landais, A., McConnell, J. R., Popp, T. J., Le Meur, E., Faïn, X., and Chappellaz, J., 2023. A 2000-year temperature reconstruction on the East Antarctic plateau from argon–nitrogen and water stable isotopes in the Aurora Basin North ice core. Clim. Past, 19, 1125–1152, https://doi.org/10.5194/cp-19-1125-2023

Analyzes of the concentration of major cations in solution

2024-02-12T11:52:47+00:00

ThermoFischer Scientific Aquion

Ionic Chromatography for cation concentrations analysis (Li⁺, Na⁺, NH₄⁺, K⁺, Rb⁺, Mg²⁺, Cs²⁺, Ca²⁺, Sr²⁺, Ba²⁺)

Instrument description

Ionic chromatography (ThermoFischer Scientific Aquion) measures the cation concentrations of solutions. The separation of cations can be done on different columns depending on the matrix and ions of interest.

Principle of analysis

A liquid sample (filtered) is introduced, from the autosampler, into an injection loop, then through a column separating the ions which arrive, one after the other, separated by the column, on a detection cell (here conductimetry). The concentration of the cations is determined in relation to a previously established calibration range.
See measurement principle here: http://spin.mines-stetienne.fr/sites/default/files/chromion.pdf

Analyses performed on the instrument

Major cations (Li⁺, Na⁺, NH₄⁺, K⁺, Rb⁺, Mg²⁺, Cs²⁺, Ca²⁺, Sr²⁺, Ba²⁺) between 0.005 and 100 ppm depending on the elements with an accuracy of +/- 5%, only on liquid solutions (filtered).

Contacts

Gaël Monvoisin : 01.69.15.71.74 / gael.monvoisin[a]universite-paris-saclay.fr

Funding

Domain of Major Interest – Patrimonial and Ancient Materials (DIM MAP) (DIM MAP) : Year 2020.

Alkalinity measurements and acid-base kinetics

2024-02-12T13:39:30+00:00

Mettler Toledo T5 Excellence

Potentiometric titrator for carbonate and bicarbonate analysis (alkalinity) or acid-base kinetics

Instrument description

The potentiometric titrator (Mettler Toledo T5 Excellence) allows to measure the concentrations of carbonate and bicarbonate ions in natural waters. It also measures the kinetics of acid-base equilibria.

Principle of analysis

A liquid sample (of known volume) is introduced into a beaker. A magnetic bar stirs the solution (a colored indicator can be added). A precision syringe adds an acid or base of known concentration to the solution. When the addition of acid or base causes the pH to vary, the instrument measures the inflection points of the pH curves. For alkalinity, around pH=8.3 is the first equivalence point which corresponds to the transformation of carbonate ions into bicarbonate ions, then a second equivalence point corresponding to the transformation of bicarbonate ions into carbonic acid around of pH=4.3. It gives the alkalinity of the sample.
See principle of measurement here: https://chimieanalytique.com/potentiometrie/

Analyses performed on the instrument

Carbonate (CO₃^2-) and bicarbonate (HCO₃^-) ions for alkalinity measurement with an accuracy of +/- 5%, 20 mL minimum sample for analysis.

Contacts

Gaël Monvoisin : 01.69.15.71.74 / gael.monvoisin[a]universite-paris-saclay.fr

Fundings

OSUPS Sciences of the Univers Observatory of university Paris-Saclay: Year 2020.

Panoply - Ice

Measurement of δ18O of liquid water and ice.

Isotope ratio mass spectrometer Finningan MAT252 coupled to an equilibration bench

Description of the instrument:

Principle of the analysis:

Type of analysis performed on this instrument:

This instrument is dedicated to the routine analysis of the oxygen isotopic composition (18O) of natural waters.

Contacts :

Measurement of δ18O and δ2H of liquid water and ice

Laser spectrometer for water isotope measurements Picarro (L2130-i)

Description of the instrument:

Principle of the analysis:

Type of analysis performed on this instrument:

Contacts :

Measurement of δ18O, δ17O and δ2H of liquid water and ice.

Laser spectrometer for water isotope measurements including 17O-excess Picarro (L2140-i)

Description of the instrument:

Principle of the analysis:

Type of analysis performed on this instrument:

Analytical precision:

1 = 0.2‰ for 18O

Contacts:

Analyzes of major cations and metallic elements concentrations in water and sediments or rocks

Agilent Technologies AAS 240 FS and GTA 120

Description of the instrument

Principle of analysis

Analyzes carried out on the instrument

Contacts

Fundings

Sub-millennial climate variability from high resolution water isotopes in the EDC ice core

The ST22 chronology for the Skytrain Ice Rise ice core – Part 2: An age model to the last interglacial and disturbed deep stratigraphy

A 2000-year temperature reconstruction on the East Antarctic plateau from argon–nitrogen and water stable isotopes in the Aurora Basin North ice core

Analyzes of the concentration of major cations in solution

ThermoFischer Scientific Aquion

Instrument description

Principle of analysis

Analyses performed on the instrument

Contacts

Funding

Alkalinity measurements and acid-base kinetics

Mettler Toledo T5 Excellence

Instrument description

Principle of analysis

Analyses performed on the instrument

Contacts

Fundings

This instrument is dedicated to the routine analysis of the oxygen isotopic composition (¹⁸O) of natural waters.

1 = 0.2‰ for ¹⁸O