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Research and teaching centre
environmental geosciences
Research and teaching centre
environmental geosciences

Applications of the Polar Ice Geochemistry Unit

Cosmogenic nuclide records of 10Be and 36Cl in the glacial record provide information on :

The variability of solar activity

over the last millennia at very high resolution from Antarctic ice cores (Baroni et al. 2011, 2019). The records of 10Be can be compared with the data from 14C from tree rings (Bard et al. 1997, Delaygue & Bard 2011). In parallel, modelling work is being carried out to reconstruct past solar forcing (Bard et al. 2000, Delaygue & Bard 2011, Schmidt et al. 2011, 2012, Jungclaus et al., 2017, Wu et al., 2018). Our solar forcing reconstructions were used for comparison of climate models (CMIP and PMIP) whose simulations were compiled in the IPCC reports (IPCC AR4, 5 and 6).

Volcanic forcing

through the identification of peak concentrations of 10Be synchronous with sulphate peaks that occur when gases emitted by a volcano reach the stratosphere, i.e. an altitude higher than about 10km (Baroni et al. 2011, 2019). These stratospheric volcanic eruptions can have a significant climatic impact in contrast to lower-altitude tropospheric eruptions.

Variations in the Earth's magnetic field

and in particular the geomagnetic excursions recorded in the Talos Dome borehole such as the Laschamp excursion that occurred about 41,000 years ago. These data are then compared with the marine records from 10Be and geomagnetic intensity. It is also a widely used tool for dating glacial records.

The Ice Age

ice that can be deduced from the isotope ratio 36Cl/10Be thanks to the principle of radioactive decay. This dating tool will be used within the framework of the ANR ToBE and the European H2020 Beyond EPICA-Oldest Ice project, which aims to obtain the oldest ice in the world, over one million years old, which is currently being drilled a few dozen km from the Dome C - Concordia station in Antarctica.

The human footprint

left by the nuclear tests of the 1950s to 1970s in the 36Cl (Pivot et al., 2019). These events are very easily identifiable because they unambiguously outperform the natural 36In addition to being used for dating, they also provide a better understanding of transport and deposition patterns from the atmosphere to the ice caps.

Antarctic stations

The snow and ice samples studied at CEREGE come exclusively from Antarctica and more particularly from the following stations

  • Talos Dome: (72°S47'S, 159°5'°E, altitude 2316 m, annual temperature -41ºC), Italian base located on the western side of the Ross Sea on the eastern side of the Antarctic High Plateau. As part of the European TALDICE drilling programme, a 1620 m ice core covering approximately 200,000 years was taken (Stenni et al. 2011).
  • Dome C (75°S, 123°E, altitude 3240 m, annual temperature -54.5ºC), Franco-Italian base located on the Antarctic High Plateau. The VOLSOL project funded by the ANR from 2009 to 2014 (ANR-09-BLAN-0003-01), has allowed the drilling of 6 ice cores of 100 m, one of which is entirely at CEREGE. This drilling covers a little over 2000 years.

  • Various sites such as Vostok, S2, Aurora Basin North for snow well collections from 2 to 6 m depth and covering the last decades (VANISH-ANR-07-VULN-013 project and the European ERC Combiniso project).

References for the Polar Ice Geochemistry Unit


Servettaz APM, Orsi AJ, Curran MAJ, Moy AD, Landais A, Agosta C, Winton VHL, Touzeau A, McConnell JR, Werner M, Baroni M. Snowfall and Water Stable Isotope Variability in East Antarctica Controlled by Warm Synoptic Events. Journal of Geophysical Research: Atmospheres. 125 (17), e2020JD032863, DOI: 10.1029/2020JD032863 (2020).


Pivot S, Baroni M, Bard E, Giraud X, ASTER Team A comparison of 36Cl nuclear bomb inputs deposited in snow from Vostok and Talos Dome, Antarctica, using the 36Cl/Cl- ratio. Journal of Geophysical Research 124 (20), 10973-10988, DOI: 10.1029/2018JD030200 (2019).

Baroni M, Bard E, Jean-Robert Petit JR, Viseur S, ASTER Team, Persistent draining of the stratospheric 10Be reservoir after the Samalas volcanic eruption (1257 CE). Journal of Geophysical Research 124 (13), 7082-7097, DOI: 10.1029/2018JD029823 (2019).

Keddadouche K, Braucher R, Bourlès DL, Baroni M, Guillou V, Léanni L, Aumaître G. Design and performance of an automated chemical extraction bench for the preparation of 10Be and 26Al targets to be analyzed by accelerator mass spectrometry. Nuclear Instruments and Methods in Physics Research Section B: 456, 230-235, DOI: 10.1016/j.nimb.2019.04.002 (2019).

O'Hare P, Mekhaldi F, Adolphi F, Raisbeck G, Aldahan A, Anderberg E, Beer J, Christl M, Fahrni S, Synal H-A, Park J, Possnert G, Southon J, Bard E, ASTER Team, Muscheler R. Multiradionuclide evidence for an extreme solar proton event around 2610 BP (≈ 660 BC). Proceedings of the National Academy of Sciences 116, 5961-5966, + 5 suppl. p., DOI: 10.1073/pnas.1815725116 (2019).

Delmonte B, Winton H, Baroni M, Baccolo G, Hansson M, Andersson P, Baroni C, Salvatore MC, Lanci L, Maggi V. Holocene dust in East Antarctica: Provenance and variability in time and space. The Holocene 30 (4), DOI: 10.1177/0959683619875188 (2019).


Wu CJ, Usoskin IG, Krivova N, Kovaltsov GA, Baroni M, Bard E, Solanki SK. Solar activity over nine millennia: A consistent multi-proxy reconstruction. Astronomy & Astrophysics 615, A93, 1-13, DOI: 10.1051/0004-6361/201731892 (2018).

Braucher R, Keddadouche K, Aumaître G, Bourlès DL, Arnold M, Pivot S, Baroni M, Scharf A, Rugel G, Bard E. Chlorine measurements at the 5MV French AMS national facility ASTER: Associated external uncertainties and comparability with the 6MV DREAMS facility. Nuclear Instruments and Methods in Physics Research B 420, 40-45, DOI: 10.1016/j.nimb.2018.01.025 (2018).


Jungclaus JH, Bard E, Baroni M, Braconnot P, Cao J, Chini LP, Egorova T, Evans M, González-Rouco JF, Goosse H, Hurtt GC, Joos F, Kaplan JO, Khodri M, Klein Goldewijk K, Krivova N, LeGrande AN, Lorenz SJ, Luterbacher J, Man W, Maycock AC, Meinshausen M, Moberg A Muscheler M, Nehrbass-Ahles C, Otto-Bliesner BI, Phipps SJ, Pongratz J, Rozanov E, Schmidt GA, Schmidt H, Schmutz W, Schurer A, Shapiro AI, Sigl M, Smerdon JE, Solanki SK, Timmreck C, Toohey M, Usoskin IG, Wagner S, Wu CJ, Yeo KL, Zanchettin D, Zhang Q, Zorita E The PMIP4 contribution to CMIP6 - Part 3: The Last Millennium, Scientific Objective and Experimental Design for the PMIP4 past1000 simulations. Geoscientific Model Development 10 (11), 4005-4033, DOI: 10.5194/gmd-10-4005-2017 (2017).


Touzeau A, Landais A, Stenni B, Uemera R, Fukui K, Guilbaud S, Ekaykin A, Casado M, Barkan E, Luz B, Magand O, Teste G, Le Meur E, Baroni M, Savarino J, Bourgeois I, Risi C. Acquisition of isotopic composition for surface snow in East Antarctica and the links to climatic parameters The Cryosphere 10, 837-852, DOI: 10.5194/tc-10-837-2016 (2016).


Delaygue G, Bekki S, Bard E, Modelling the stratospheric budget of beryllium isotopes. Tellus B 67, 28582, 1-16, DOI: 10.3402/tellusb.v67.28582 (2015).

Cauquoin A, Landais A, Raisbeck GM, Jouzel J, Bazin L, Kageyama M, Peterschmitt JY, Werner M, Bard E, ASTER Team. Comparing past accumulation rate reconstructions in East Antarctic ice cores using 10Be, water isotopes and CMIP5-PMIP3 models. Climate of the Past 11, 355-367, DOI: 10.5194/cp-11-355-2015 (2015).


Cauquoin A, Raisbeck GM, Jouzel J, Bard E, ASTER Team. No evidence for planetary influence on solar activity 330 ka ago. Astronomy & Astrophysics 561, A132, 1-5, DOI: 10.1051/0004-6361/201322879, (2014).


Winkler R, Landais A, Risi C, Baroni M, Ekaykin A, Jouzel J, Petit JR, Prie F, Minster B, Falourd S. Interannual variation of water isotopologues at Vostok indicates a contribution from stratospheric water vapor. Proceedings of the National Academy of Sciences 110, 17674-17679, DOI: 10.1073/pnas.1215209110, (2013).


Schmidt GA, Jungclaus JH, Ammann CM, Bard E, Braconnot P, Crowley TJ, Delaygue G, Joos F, Krivova NA, Muscheler R, Otto-Bliesner BL, Pongratz J, Shindell DT, Solanki SK, Steinhilber F, Vieira LEA. Climate forcing reconstructions for use in PMIP simulations of the Last Millennium (v1.1). Geoscientific Model Development 5, 185-191, DOI: 10.5194/gmd-5-185-2012, (2012).


Baroni M, Bard E, Petit JR, Magand O, Bourlès D. Volcanic, solar activity, and atmospheric circulation influences on cosmogenic 10Be fallout at Vostok and Concordia (Antarctica) over the last 60 years. Geochimica et Cosmochimica Acta 71, 7132-7145, DOI: 10.1016/j.gca.2011.09.002, (2011).

Schmidt GA, Jungclaus JH, Ammann CM, Bard E, Braconnot P, Crowley TJ, Delaygue G, Joos F, Krivova NA, Muscheler R, Otto-Bliesner BL, Pongratz J, Shindell DT, Solanki SK, Steinhilber F, Vieira LEA. Climate forcing reconstructions for use in PMIP simulations of the Last Millennium (v1.0). Geoscientific Model Development 4, 33-45, DOI: 10.5194/gmd-4-33-2011, (2011).

Stenni B, Buiron D, Frezzotti M, Albani S, Barbante C, Bard E, Barnola JM, Baroni M, Baumgartner M, Bonazza M, Capron E, Castellano E, Chappellaz J, Delmonte B, Falourd S, Genoni L, Iacumin P, Jouzel J, Kipfstuhl S, Landais A Lemieux-Dudon B, Maggi V, Masson-Delmotte V, Mazzola C, Minster B, Montagnat M, Mulvaney R, Narcisi B, Oerter H, Parrenin F, Petit JR, Ritz C, Scarchilli C, Schilt A, Schüpbach S, Schwander J, Selmo E, Severi M, Stocker TF, Udisti U. Unified Antarctic and Greenland climate seesaw during the last deglaciation. Nature Geoscience 4, 46-49 + 32 supplementary pages, DOI: 10.1038/NGEO1026, (2011).

Delaygue G, Bard E. An Antarctic view of beryllium-10 and solar activity for the past millennium. Climate Dynamics 36, 2201-2218, DOI:10.1007/s00382-010-0795-1, (2011).


Usoskin IG, Horiuchi K, Solanki S, Kovaltsov GA, Bard E. On the common solar signal in different cosmogenic isotope data sets. Journal of Geophysical Research 114, 1-14, DOI:10.1029/2008JA013888, (2009).


Bard E, Raisbeck G, Yiou F, Jouzel J. Comment on "Solar activity during the last 1000 yr inferred from radionuclide records" by Muscheler et al. (2007). Quaternary Science Reviews 26, 2301-2308, (2007).


Bard E, Frank M. Climate change and solar variability: what's new under the Sun. Earth and Planetary Science Letters 248, 1-14, (2006).


Bard E, Raisbeck G, Yiou F, Jouzel J Solar irradiance during the last 1200 yr based on cosmogenic nuclides. Tellus B 52, 985-992, (2000).


Bard E. Nucleide production by cosmic rays during the Last Ice Age. Science 277, 532-533, (1997).

Bard E, Raisbeck G, Yiou F, Jouzel J Solar modulation of cosmogenic nuclide production over the last millennium: comparison between 14C and 10Be records. Earth and Planetary Science Letters 150, 453-462, (1997).


Raisbeck GM, Yiou F, Jouzel J, Petit JR, Barkov NI, Bard E. 10Be deposition at Vostok, Antarctica, during the last 50,000 years and its relationship to possible cosmogenic production variations during this period. In Bard E & Broecker WS eds: The Last Deglaciation: Absolute and Radiocarbon Chronologies, NATO ASI series, I vol 2. Springer Verlag, 127-140, (1992).