More Than 200 Meters of Lake Ice Above Subglacial Lake Vostok, Antarctica
10.1126/science.286.5447.2138
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

Isotope studies show that the Vostok ice core consists of ice refrozen from Lake Vostok water, from 3539 meters below the surface of the Antarctic ice sheet to its bottom at about 3750 meters. Additional evidence comes from the total gas content, crystal size, and electrical conductivity of the ice. The Vostok site is a likely place for water freezing at the lake-ice interface, because this interface occurs at a higher level here than anywhere else above the lake. Isotopic data suggest that subglacial Lake Vostok is an open system with an efficient circulation of water that was formed during periods that were slightly warmer than those of the past 420,000 years. Lake ice recovered by deep drilling is of interest for preliminary investigations of lake chemistry and bedrock properties and for the search for indigenous lake microorganisms. This latter aspect is of potential importance for the exploration of icy planets and moons.

Bibliography

Jouzel, J., Petit, J. R., Souchez, R., Barkov, N. I., Lipenkov, V. Ya., Raynaud, D., Stievenard, M., Vassiliev, N. I., Verbeke, V., & Vimeux, F. (1999). More Than 200 Meters of Lake Ice Above Subglacial Lake Vostok, Antarctica. Science, 286(5447), 2138–2141.

Authors 10
  1. J. Jouzel (first)
  2. J. R. Petit (additional)
  3. R. Souchez (additional)
  4. N. I. Barkov (additional)
  5. V. Ya. Lipenkov (additional)
  6. D. Raynaud (additional)
  7. M. Stievenard (additional)
  8. N. I. Vassiliev (additional)
  9. V. Verbeke (additional)
  10. F. Vimeux (additional)
References 33 Referenced 153
  1. 10.1038/20859
  2. . Ice coring was stopped at 3623 m the depth reached in January 1998 which is about 120 m above the interface with subglacial Lake Vostok (4) to avoid any contamination by the drilling fluid.
  3. V. Lipenkov and N. Barkov Proceedings of the International Workshop on Lake Vostok. Lake Vostok Study: Scientific Objectives and Technical Requirements (Arctic and Antarctic Research Institute St. Petersburg Russia 1998) p. 31.
  4. Martinerie P., et al., J. Geophys. Res. 99, 10565 (1994). (10.1029/93JD03223) / J. Geophys. Res. by Martinerie P. (1994)
  5. Lake Vostok is 230 km long and 50 km wide and has an area of about 14 000 km 2 . The Vostok drilling site (Fig. 1) is at the southern end of the lake and has a thickness of 3750 m of ice with 600 m of water below the ice. At its northern end 200 km away the ice is 4300 m thick and the water below is shallower. For more information see
  6. Kapitsa A., et al., Nature 381, 684 (1996); (10.1038/381684a0) / Nature by Kapitsa A. (1996)
  7. Siegert M., Ridley J., J. Geophys. Res. 103, 10195 (1998). (10.1029/98JB00390) / J. Geophys. Res. by Siegert M. (1998)
  8. The δ 18 O notation is δ 18 O = [( 18 O/ 16 O) sample /( 18 O/ 16 O) std − 1] × 1000 where std is the standard mean ocean water reference (the same applies for δD).
  9. 10.1038/18860
  10. This slope is similar to that of 7.86 obtained for the past 150 ky (6) and is close to that of the worldwide Meteoric Water Line (slope of 8) [
  11. 10.1126/science.133.3465.1702
  12. ]. Both δD and δ 18 O have now been measured down to 3611 m. In a δD/δ 18 O diagram data points from zones I and D are undistinguishable from those of the past 420 ky (zone C) as illustrated by the individual data points from the bottom part of zone D (Fig. 2).
  13. Jouzel J., Souchez R., J. Glaciol. 28, 35 (1982). (10.3189/S0022143000011771) / J. Glaciol. by Jouzel J. (1982)
  14. Souchez R., Jouzel J., J. Glaciol. 30, 369 (1984). (10.3189/S0022143000006249) / J. Glaciol. by Souchez R. (1984)
  15. Diffusion coefficients of HDO and H 2 18 O molecules in ice are very low on the order of 10 −11 cm 2 s −1 . The same coefficients in liquid water are on the order of 10 −5 cm 2 s −1 .
  16. There is no reason to expect a significant change of the δD/δ 18 O relation for periods before 420 ka because the central part of the Antarctic ice sheet and its surrounding oceans probably have not been subject to changes larger than those during the past 420 ky.
  17. A numerical simulation with the use of a simple diffusion model and the assumption that pure diffusion is limited to the boundary layer at the ice-water interface is described [
  18. Souchez R., et al., Geophys. Res. Lett. 14, 599 (1987); (10.1029/GL014i006p00599) / Geophys. Res. Lett. by Souchez R. (1987)
  19. ]. This shows that a higher freezing rate will produce a weaker isotopic enrichment in the ice than that produced at equilibrium.
  20. Salamatin A., Vostretsov R. N., Petit J. R., Lipenkov V. Y., Barkov N. I., Data Glaciol. Stud. 85, 233 (1998). / Data Glaciol. Stud. by Salamatin A. (1998)
  21. This second process is illustrated by an experiment of progressive freezing (top left of Fig. 2) adapted from R. Souchez and J. Jouzel (9). Although freezing is sufficiently slow for isotopic equilibrium to be achieved at the liquid-water interface both the newly formed ice and the remaining liquid become more depleted in heavy isotopes during the course of this experiment. In a closed system (Rayleigh model) the isotopic content of the liquid is equal to [(1 + δ 1 )] × f (α−1) ) − 1 where δ 1 is the isotopic content of the initial liquid reservoir and f is the fraction of liquid remaining. The apparent 60% enrichment of the ice in comparison to the initial liquid is obtained when ∼30% of the reservoir has frozen. As expected from the Rayleigh model the data both for ice and liquid samples align on the freezing slope and such laboratory experiments were used to support the melting-refreezing theory that two of us have developed (8 9). This experimental freezing slope is close to the theoretical value (Fig. 2).
  22. The sample in the transition aligns on the straight line that is defined by the cluster of samples above (disturbed glacier ice) and below (lake ice) but has a slope (4.88) significantly higher than 3.98. We interpret this alignment as a result of a diffusion process at a sharp transition between the two types of ice and not as a freezing effect.
  23. Paillard D., Nature 391, 378 (1998); (10.1038/34891) / Nature by Paillard D. (1998)
  24. Tiedeman R., et al., Paleoceanography 9, 619 (1994); (10.1029/94PA00208) / Paleoceanography by Tiedeman R. (1994)
  25. . Data suggest that there was a warmer global climate (lower continental ice volume) for the period between 2 million and 1 million years ago than for the past 1 million years.
  26. 10.1126/science.286.5447.2141
  27. 10.1126/science.286.5447.2144
  28. J. M. Tiedje in (21) p. 19; D. C. White in (21) p. 22.
  29. R. G. Kern in (21) p. 24.
  30. F. Carsey in (21) p. 21.
  31. National Science Foundation Workshop–The Lake Vostok Study: A Curiosity or a Focus for Interdisciplinary Investigations Washington DC 7 to 8 September 1998. See www.ldeo.columbia.edu/vostok/.
  32. Lipenkov V., et al., J. Glaciol. 41, 423 (1995). (10.3189/S0022143000016294) / J. Glaciol. by Lipenkov V. (1995)
  33. This work is part of the joint project between Russia France and the United States to study the Vostok ice core. We are indebted to the Russian drill engineers from the St. Petersburg Mining Institute who conducted the field operations and we thank all participants for field work and ice sampling. We acknowledge the Russian Antarctic Expeditions (RAE) the Institut Français de Recherches et Technologies Polaires (IFRTP) and the Division of Polar Programs (NSF) for logistic support. The project is supported in Russia by the Russian Ministry of Sciences; in France by the PNEDC (Programme National d'Etudes de la Dynamique du Climat) and by the Commission of European Communities (Environment Programme ENV4-CT95-0130); and in the United States by NSF. R.S. and V.V. are grateful for the support of the Belgian Antarctic programme (Science Policy Office). We thank J. M. Barnola J. Chappellaz M. Delmotte P. Duval F. Ferron G. Hoffmann J. L. Jaffrezo P. Jean-Baptiste D. Paillard L. Pépin A. Salamatin and D. Weis for helpful discussions and comments on the manuscript and T. Sowers and an anonymous reviewer for constructive criticism.
Dates
Type When
Created 23 years, 1 month ago (July 27, 2002, 5:37 a.m.)
Deposited 1 year, 7 months ago (Jan. 13, 2024, 5:31 a.m.)
Indexed 1 week ago (Aug. 22, 2025, 12:45 a.m.)
Issued 25 years, 8 months ago (Dec. 10, 1999)
Published 25 years, 8 months ago (Dec. 10, 1999)
Published Print 25 years, 8 months ago (Dec. 10, 1999)
Funders 0

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@article{Jouzel_1999, title={More Than 200 Meters of Lake Ice Above Subglacial Lake Vostok, Antarctica}, volume={286}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.286.5447.2138}, DOI={10.1126/science.286.5447.2138}, number={5447}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Jouzel, J. and Petit, J. R. and Souchez, R. and Barkov, N. I. and Lipenkov, V. Ya. and Raynaud, D. and Stievenard, M. and Vassiliev, N. I. and Verbeke, V. and Vimeux, F.}, year={1999}, month=dec, pages={2138–2141} }