740,000-year Deuterium Record in an Ice Core from Dome C, Antarctica

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Authors

Jean Jouzel
Institut Pierre Simon Laplace,
Laboratoire des Sciences du Climat et de l'Environnement UMR CEA-CNRS 1572,
Saclay, Orme des Merisiers,
CEA Saclay, 91191 Gif-sur-Yvette, France

Period of Record

740,000 years BP-present

Methods

Because isotopic fractions of the heavier oxygen-18 (¹⁸O) and deuterium (²H) in snowfall are temperature-dependent and a strong spatial correlation exists between the annual mean temperature and the mean isotopic fraction of ¹⁸O or ²H in precipitation, it is possible to derive temperature records from the records of those isotopes in ice cores.

Deuterium values are expressed as δD, which is defined as:

δD = {[(²H/¹H)_sample - (²H/¹H)_V-SMOW] (²H/¹H)_V-SMOW} X 1000

where (²H/¹H)_sample is the ratio of deuterium to ordinary hydrogen in sample corresponding to a particular datum, and (²H/¹H) _V-SMOW is the ratio of deuterium to ordinary hydrogen in Vienna Standard Mean Ocean Water (V-SMOW).

The deuterium content distribution is well documented over East Antarctica and over a large range of temperatures (-20° to -55° C); there is a linear relationship between the average annual surface temperature and the snow deuterium content. The slope of this δD/surface temperature relationship was found by Jouzel et al. (1993, 1996) and Petit et al. (1999) to be 9°/_°° per °C. Further details on the methodology are presented in Jouzel et al. (1987), Lorius et al. (1985), and Petit et al. (1999).

The record presented by Jouzel et al. (1987), based on data in a 2083-meter ice core from the Russian Vostok station in central east Antarctica, was the first such record to span a full glacial-interglacial cycle. Drilling continued at Vostok until January 1998, reaching a depth of 3623 m, and a corresponding time of ~420 kyr BP. More recently, a 740-kyr deuterium record has been extracted from an ice core taken at Dome C (EPICA Community Members, 2004). Deuterium fractions were determined in meltwater from 55-cm long sections of the ice core the surface down to the bottom of the core.

Dome C, Antarctica
76°06' S, 123°21'E
3233 m above MSL

Trends

For the 4 most recent glacial cycles the data corroborate the VOSTOK record. Apparently the four previous interglacials (peaks in the time series) were not as warm, but they lasted longer.

References

• EPICA Community Members. 2004. Eight glacial cycles from an Antarctic ice core. Nature 429:623-628.
• Jouzel, J., C. Lorius, J.R. Petit, C. Genthon, N.I. Barkov, V.M. Kotlyakov, and V.M.Petrov. 1987. Vostok ice core: a continuous isotope temperature record over the last climatic cycle (160,000 years). Nature 329:403-8.
• Jouzel, J., N.I. Barkov, J.M. Barnola, M. Bender, J. Chappellaz, C. Genthon, V.M. Kotlyakov, V. Lipenkov, C. Lorius, J.R. Petit, D. Raynaud, G. Raisbeck, C. Ritz, T. Sowers, M. Stievenard, F. Yiou, and P. Yiou. 1993. Extending the Vostok ice-core record of palaeoclimate to the penultimate glacial period. Nature 364:407-12.
• Jouzel, J., C. Waelbroeck, B. Malaize, M. Bender, J.R. Petit, M. Stievenard, N.I. Barkov, J.M. Barnola, T. King, V.M. Kotlyakov, V. Lipenkov, C. Lorius, D. Raynaud, C. Ritz, and T. Sowers. 1996. Climatic interpretation of the recently extended Vostok ice records. Climate Dynamics 12:513-521.
• Lorius, C., J. Jouzel, C. Ritz, L. Merlivat, N.I. Barkov, Y.S. Korotkevich, and V.M. Kotlyakov. 1985. A 150,000-year climatic record from Antarctic ice. Nature 316:591-96.
• Petit, J.R., J. Jouzel, D. Raynaud, N.I. Barkov, J.-M. Barnola, I. Basile, M. Bender, J. Chappellaz, M. Davis, G. Delayque, M. Delmotte, V.M. Kotlyakov, M. Legrand, V.Y. Lipenkov, C. Lorius, L. Pépin, C. Ritz, E. Saltzman, and M. Stievenard. 1999. Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica. Nature 399: 429-436.

12/2004