Tightened constraints on the time-lag between Antarctic temperature and CO 2 during the last deglaciation
Antarctic ice cores provide clear evidence ofa close coupling between variations in Antarctic temperatureand the atmospheric concentration of CO 2 during theglacial/interglacial cycles of at least the past 800-thousandyears. Precise information on the relative timing of the temperatureand CO 2 chang...
| Published in: | Climate of the Past |
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| Main Authors: | , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Copernicus Publications
2012
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| Subjects: | |
| Online Access: | https://doi.org/10.5194/cp-8-1213-2012 http://ecite.utas.edu.au/83685 |
| Summary: | Antarctic ice cores provide clear evidence ofa close coupling between variations in Antarctic temperatureand the atmospheric concentration of CO 2 during theglacial/interglacial cycles of at least the past 800-thousandyears. Precise information on the relative timing of the temperatureand CO 2 changes can assist in refining our understandingof the physical processes involved in this coupling.Here, we focus on the last deglaciation, 19 000 to 11 000 yrbefore present, during which CO 2 concentrations increasedby ~80 parts per million by volume and Antarctic temperatureincreased by ~10 Celsius degree. Utilising a recently developedproxy for regional Antarctic temperature, derived from fivenear-coastal ice cores and two ice core CO 2 records with highdating precision, we show that the increase in CO 2 likelylagged the increase in regional Antarctic temperature by lessthan 400 yr and that even a short lead of CO 2 over temperaturecannot be excluded. This result, consistent for bothCO 2 records, implies a faster coupling between temperatureand CO 2 than previous estimates, which had permitted up tomillennial-scale lags. |
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