Two-phase change in CO 2, Antarctic temperature and global climate during Termination II

• Published in: Nature Geoscience
• Main Authors: Landais, A., Dreyfus, G., Capron, E., Jouzel, J., Masson-Delmotte, V., Roche, D. M., Prie, F., Caillon, N., Chappellaz, J., Leuenberger, M., Lourantou, A., Parrenin, F., Raynaud, D., Teste, G.
• Format: Text
• Language: unknown
• Published: New York, Springer Science and Business Media LLC 2022
• Subjects: Antarctic; Antarc*; Antarctica; EPICA; ice core
• Online Access: https://doi.org/10.1038/ngeo1985; http://infoscience.epfl.ch/record/298398

The end of the Last Glacial Maximum (Termination I), roughly 20 thousand years ago (ka), was marked by cooling in the Northern Hemisphere, a weakening of the Asian monsoon, a rise in atmospheric CO 2 concentrations and warming over Antarctica. The sequence of events associated with the previous glacial-interglacial transition (Termination II), roughly 136 ka, is less well constrained. Here we present high-resolution records of atmospheric CO 2 concentrations and isotopic composition of N 2 - an atmospheric temperature proxy - from air bubbles in the EPICA Dome C ice core that span Termination II. We find that atmospheric CO 2 concentrations and Antarctic temperature started increasing in phase around 136 ka, but in a second phase of Termination II, from 130.5 to 129 ka, the rise in atmospheric CO 2 concentrations lagged that of Antarctic temperature unequivocally. We suggest that during this second phase, the intensification of the low-latitude hydrological cycle resulted in the development of a CO 2 sink, which counteracted the CO 2 outgassing from the Southern Hemisphere oceans over this period. © 2013 Macmillan Publishers Limited.