Abstract
Glacial–interglacial deep Indo-Pacific carbonate ion concentration ([CO32−]) changes were mainly driven by two mechanisms that operated on different timescales: 1) a long-term increase during glaciation caused by a carbonate deposition reduction on shelves (i.e., the coral reef hypothesis), and 2) transient carbonate compensation responses to deep ocean carbon storage changes. To investigate these mechanisms, we have used benthic foraminiferal B/Ca to reconstruct deep-water [CO32−] in cores from the deep Indian and Equatorial Pacific Oceans during the past five glacial cycles. Based on our reconstructions, we suggest that the shelf-to-basin shift of carbonate deposition raised deep-water [CO32−], on average, by 7.3 ± 0.5 (SE) μmol/kg during glaciations. Oceanic carbon reorganisations during major climatic transitions caused deep-water [CO32−] deviations away from the long-term trend, and carbonate compensation processes subsequently acted to restore the ocean carbonate system to new steady state conditions. Deep-water [CO32−] showed similar patterns to sediment carbonate content (%CaCO3) records on glacial–interglacial timescales, suggesting that past seafloor %CaCO3 variations were dominated by deep-water carbonate preservation changes at our studied sites.
| Original language | English |
|---|---|
| Pages (from-to) | 42-53 |
| Number of pages | 12 |
| Journal | Earth and Planetary Science Letters |
| Volume | 471 |
| DOIs | |
| Publication status | Published - 1 Aug 2017 |
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The effect of ocean alkalinity and carbon transfer on deep-sea carbonate ion concentration during the past five glacial cycles. / Kerr, Joanna; Rickaby, Rosalind; Yu, Jimin; Elderfield, Henry; Sadekov, Aleksey Yu.
In: Earth and Planetary Science Letters, Vol. 471, 01.08.2017, p. 42-53.Research output: Contribution to journal › Article
TY - JOUR
T1 - The effect of ocean alkalinity and carbon transfer on deep-sea carbonate ion concentration during the past five glacial cycles
AU - Kerr, Joanna
AU - Rickaby, Rosalind
AU - Yu, Jimin
AU - Elderfield, Henry
AU - Sadekov, Aleksey Yu
PY - 2017/8/1
Y1 - 2017/8/1
N2 - Glacial–interglacial deep Indo-Pacific carbonate ion concentration ([CO32−]) changes were mainly driven by two mechanisms that operated on different timescales: 1) a long-term increase during glaciation caused by a carbonate deposition reduction on shelves (i.e., the coral reef hypothesis), and 2) transient carbonate compensation responses to deep ocean carbon storage changes. To investigate these mechanisms, we have used benthic foraminiferal B/Ca to reconstruct deep-water [CO32−] in cores from the deep Indian and Equatorial Pacific Oceans during the past five glacial cycles. Based on our reconstructions, we suggest that the shelf-to-basin shift of carbonate deposition raised deep-water [CO32−], on average, by 7.3 ± 0.5 (SE) μmol/kg during glaciations. Oceanic carbon reorganisations during major climatic transitions caused deep-water [CO32−] deviations away from the long-term trend, and carbonate compensation processes subsequently acted to restore the ocean carbonate system to new steady state conditions. Deep-water [CO32−] showed similar patterns to sediment carbonate content (%CaCO3) records on glacial–interglacial timescales, suggesting that past seafloor %CaCO3 variations were dominated by deep-water carbonate preservation changes at our studied sites.
AB - Glacial–interglacial deep Indo-Pacific carbonate ion concentration ([CO32−]) changes were mainly driven by two mechanisms that operated on different timescales: 1) a long-term increase during glaciation caused by a carbonate deposition reduction on shelves (i.e., the coral reef hypothesis), and 2) transient carbonate compensation responses to deep ocean carbon storage changes. To investigate these mechanisms, we have used benthic foraminiferal B/Ca to reconstruct deep-water [CO32−] in cores from the deep Indian and Equatorial Pacific Oceans during the past five glacial cycles. Based on our reconstructions, we suggest that the shelf-to-basin shift of carbonate deposition raised deep-water [CO32−], on average, by 7.3 ± 0.5 (SE) μmol/kg during glaciations. Oceanic carbon reorganisations during major climatic transitions caused deep-water [CO32−] deviations away from the long-term trend, and carbonate compensation processes subsequently acted to restore the ocean carbonate system to new steady state conditions. Deep-water [CO32−] showed similar patterns to sediment carbonate content (%CaCO3) records on glacial–interglacial timescales, suggesting that past seafloor %CaCO3 variations were dominated by deep-water carbonate preservation changes at our studied sites.
KW - alkalinity
KW - carbonate compensation
KW - carbonate ion
KW - coral reef hypothesis
KW - glacial
UR - http://www.scopus.com/inward/record.url?scp=85019401149&partnerID=8YFLogxK
U2 - 10.1016/j.epsl.2017.04.042
DO - 10.1016/j.epsl.2017.04.042
M3 - Article
VL - 471
SP - 42
EP - 53
JO - Earth & Planetary Science Letters
JF - Earth & Planetary Science Letters
SN - 0012-821X
ER -