carbon
; carbon dioxide
; ice
; air
; Antarctica
; Article
; atmosphere
; deglaciation
; gas exchange
; Holocene
; Northern Hemisphere
; oxidation
; priority journal
; sea
; temperature
; trend study
英文摘要:
An understanding of the mechanisms that control CO2 change during glacial-interglacial cycles remains elusive. Here we help to constrain changing sources with a high-precision, high-resolution deglacial record of the stable isotopic composition of carbon in CO2 (δ13C-CO2) in air extracted from ice samples from Taylor Glacier, Antarctica. During the initial rise in atmospheric CO2 from 17.6 to 15.5 ka, these data demarcate a decrease in δ13C-CO2, likely due to a weakened oceanic biological pump. From 15.5 to 11.5 ka, the continued atmospheric CO2 rise of 40 ppm is associated with small changes in δ13C-CO2, consistent with a nearly equal contribution from a further weakening of the biological pump and rising ocean temperature. These two trends, related to marine sources, are punctuated at 16.3 and 12.9 ka with abrupt, century-scale perturbations in δ13C-CO2 that suggest rapid oxidation of organic land carbon or enhanced air-sea gas exchange in the Southern Ocean. Additional century-scale increases in atmospheric CO2 coincident with increases in atmospheric CH4 and Northern Hemisphere temperature at the onset of the BØlling (14.6-14.3 ka) and Holocene (11.6-11.4 ka) intervals are associated with small changes in δ13C-CO2, suggesting a combination of sources that included rising surface ocean temperature.
Bauska, T.K., College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, United States, Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, United Kingdom; Baggenstos, D., Scripps Institution of Oceanography, University of California, San Diego, San Diego, CA 92093, United States; Brook, E.J., College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, United States; Mix, A.C., College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, United States; Marcott, S.A., Department of Geoscience, University of Wisconsin-Madison, Madison, WI 53706, United States; Petrenko, V.V., Department of Earth and Environmental Sciences, University of Rochester, Rochester, NY 14627, United States; Schaefer, H., Climate and Atmosphere Center, National Institute of Water, Atmospheric Research Ltd., Wellington, 6023, New Zealand; Severinghaus, J.P., Scripps Institution of Oceanography, University of California, San Diego, San Diego, CA 92093, United States; Lee, J.E., College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, United States; Thiemens, M.H., University of California, San Diego, San Diego, CA, United States
Recommended Citation:
Bauska T.K.,Baggenstos D.,Brook E.J.,et al. Carbon isotopes characterize rapid changes in atmospheric carbon dioxide during the last deglaciation[J]. Proceedings of the National Academy of Sciences of the United States of America,2016-01-01,113(13)