TY - JOUR

T1 - О возможности реконструкции климатического сигнала в нарушенной записи изотопного состава древнего льда (0,4–1,2 млн лет назад) в керне станции Восток (Центральная Антарктида)

AU - Екайкин, А. А.

AU - Липенков, В. Я.

AU - Верес, А. Н.

AU - Козачек, А. В.

AU - Скакун, А. А.

PY - 2019/1/1

Y1 - 2019/1/1

N2 - In this work we have presented new detailed (with the resolution of 10 cm) stable water isotope (dD and δ18O) profile measured in the central Antarctic Vostok ice core section that contains old ice with the age from 0.4 to 1.2 million years. To interpret these data we have developed a model of molecular diffusion in ice and determined the value of so-called «diffusion length». We have demonstrated that the climatic signal in this ice interval is disturbed by a combination of two processes, ice layer folding (that is accompanied by layer overturning and mixing) and molecular diffusion. The whole old ice interval can be divided in 5 zones that differ in terms of character and intensity of these two processes. In three of these zones the climatic signal is partly preserved and could be restored to some extent. However, in the most interesting and old zone 5 (0.75-1.2 Ma) the climatic signal is nearly completely erased and could hardly be reconstructed. At the same time, the isotopic records obtained from the Vostok old ice have preserved the information on the mean level of the isotopic content of ice in glacial and interglacial stages. This gives an opportunity to reveal and study long-term climatic trends with typical duration longer than main climatic cycles (40-100 ka).

AB - In this work we have presented new detailed (with the resolution of 10 cm) stable water isotope (dD and δ18O) profile measured in the central Antarctic Vostok ice core section that contains old ice with the age from 0.4 to 1.2 million years. To interpret these data we have developed a model of molecular diffusion in ice and determined the value of so-called «diffusion length». We have demonstrated that the climatic signal in this ice interval is disturbed by a combination of two processes, ice layer folding (that is accompanied by layer overturning and mixing) and molecular diffusion. The whole old ice interval can be divided in 5 zones that differ in terms of character and intensity of these two processes. In three of these zones the climatic signal is partly preserved and could be restored to some extent. However, in the most interesting and old zone 5 (0.75-1.2 Ma) the climatic signal is nearly completely erased and could hardly be reconstructed. At the same time, the isotopic records obtained from the Vostok old ice have preserved the information on the mean level of the isotopic content of ice in glacial and interglacial stages. This gives an opportunity to reveal and study long-term climatic trends with typical duration longer than main climatic cycles (40-100 ka).

KW - Antarctica

KW - Ice cores

KW - Mid-Pleistocene Transition

KW - Old ice

KW - Paleoclimate

KW - Stable water isotopes

KW - Vostok station

UR - http://www.scopus.com/inward/record.url?scp=85078048085&partnerID=8YFLogxK

U2 - 10.15356/2076-6734-2019-4-463

DO - 10.15356/2076-6734-2019-4-463

M3 - статья

AN - SCOPUS:85078048085

VL - 59

SP - 437

EP - 451

JO - Лед и Снег

JF - Лед и Снег

SN - 2076-6734

IS - 4

ER -