The water isotope module

The water isotope module is mainly done at the LSCE (Paris Saclay), which has historic equipment and expertise in this field.

The measurements

The measurements are made on different machines, located at the LSCE, apart from a Picarro installed on the IGE’s CFA :

• Thanks to the Finnigan MAT 252 mass spectrometer, d18O measurements are carried out with very good accuracy.


Learn more here, and here.

• The Picarro L-2120i allows measurements of deuterium and d18O (less accurate) in natural waters.


Learn more here, and there.

• A Picarro L-2140i allows measurements of the triple composition of water (deuterium, d18O et D17O) , but the precision of 17O-excess is lower than the one obtained on the mass spectrometer, and it is not used for these measurements at the LSCE. Learn more here, and here.

• An other Picarro L-2140i is mounted on the CFA of the IGE, at Grenoble.

• The isotopic triple composition of water is measured with a Finnigan MAT 253. Learn more here.

• Eventually, a CFA will allow the continuous measurement of the core.


The measurement of water isotopes in the ice allows the reconstruction of temperature variations in the past and has made it possible to establish the close link between the concentration of greenhouse gases and the Earth’s temperature over the last 800,000 years (EPICA drilling).

Updated on 13 mai 2020