Minimal Antarctic sea ice during the Pliocene
Antarctic sea-ice concentration at Ocean Drilling Program Sites 1165 (64.380S, 67.219E) and 1166 (67.696S, 74.787E) was lower than today through much of the Pliocene. The low sea-ice concentration is evident from the proportion of the diatom Eucampia antarctica with intercalary valves (Eucampia inde...
| Published in: | Geology |
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| Main Authors: | , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Geological Society of America
2005
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| Subjects: | |
| Online Access: | https://doi.org/10.1130/G21013.1 http://ecite.utas.edu.au/34526 |
| Summary: | Antarctic sea-ice concentration at Ocean Drilling Program Sites 1165 (64.380S, 67.219E) and 1166 (67.696S, 74.787E) was lower than today through much of the Pliocene. The low sea-ice concentration is evident from the proportion of the diatom Eucampia antarctica with intercalary valves (Eucampia index). This sea-ice proxy was calibrated by using modern diatom data obtained from core-top samples and winter sea-ice concentration data (September average through 1979-1987). The modern relationship is expressed as a binomial generalized linear model (modern sea-ice model). This model was applied to the Pliocene Eucampia index within a 95% tolerance interval (obtained from bootstrap estimates). The results indicate that reduced winter sea-ice concentrations persisted through much of the Pliocene and at times were 78% and 61% relatively less concentrated than today at Sites 1165 and 1166, respectively. 2005 Geological Society of America. |
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