Dating of an East Antarctic ice core (GV7) by high resolution chemical stratigraphies
Ice core dating is the first step for a correct interpretation of climatic and environmental changes. In this work, we release a stratigraphic dating of the uppermost 197 m of the 250 m deep GV7(B) ice core (drilling site, 70°41’S, 158°52’E, 1950 m a.s.l.) with a sub-annual resolution. Chemical stra...
Main Authors: | , , , , , , , , , , , , , , , , , |
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Format: | Text |
Language: | English |
Published: |
2021
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Subjects: | |
Online Access: | https://doi.org/10.5194/cp-2021-44 https://cp.copernicus.org/preprints/cp-2021-44/ |
Summary: | Ice core dating is the first step for a correct interpretation of climatic and environmental changes. In this work, we release a stratigraphic dating of the uppermost 197 m of the 250 m deep GV7(B) ice core (drilling site, 70°41’S, 158°52’E, 1950 m a.s.l.) with a sub-annual resolution. Chemical stratigraphies of NO 3 − , MSA (methanesulfonic acid), non-sea salt SO 4 2− , sea-salt ions and the oxygen isotopic composition (δ 18 O) were used in the annual layer counting upon the identification of a seasonal profile in their records. Different procedures were tested and thanks to the volcanic history of the core, obtained in previous works, an accurate age-depth correlation was obtained for the period 1179–2009 CE. Once the dating of the core was finalized, the annual mean accumulation rate was evaluated throughout the analyzed 197 m of the core, obtaining an annually resolved history of the snow accumulation on site in the last millennium. A small, yet consistent, rise in accumulation rate was found for the last 830 years since the middle of the 18 th century. |
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