During the last deglaciation (19,000–9,000 years ago), atmospheric CO2 increased by about 80 ppm. Understanding the mechanisms responsible for this change is a central theme of palaeoclimatology, relevant for predicting future CO2 transfers in a warming world. Deglacial CO2 rise hypothetically tapped an accumulated deep Pacific carbon reservoir, but the processes remain elusive as they are underconstrained by existing tracers. Here we report high-resolution authigenic neodymium isotope data in North Pacific sediment cores and infer abyssal Pacific overturning weaker than today during the Last Glacial Maximum but intermittently stronger during steps of deglacial CO2 rise. Radiocarbon evidence suggestive of relatively ‘old’ deglacial deep Pacific water is reinterpreted here as an increase in preformed 14C age of subsurface waters sourced near Antarctica, consistent with movement of aged carbon out of the deep ocean and release of CO2 to the atmosphere during the abyssal flushing events. The timing of neodymium isotope changes suggests that deglacial acceleration of Pacific abyssal circulation tracked Southern Hemisphere warming, sea-ice retreat and increase of mean ocean temperature. The inferred magnitude of circulation changes is consistent with deep Pacific flushing as a significant, and perhaps dominant, control of the deglacial rise of atmospheric CO2.
This is a preview of subscription content, access via your institution
Open Access articles citing this article.
Indian Ocean glacial deoxygenation and respired carbon accumulation during mid-late Quaternary ice ages
Nature Communications Open Access 10 August 2023
Nature Geoscience Open Access 03 April 2023
Nature Communications Open Access 16 September 2022
Access Nature and 54 other Nature Portfolio journals
Get Nature+, our best-value online-access subscription
$29.99 / 30 days
cancel any time
Subscribe to this journal
Receive 12 print issues and online access
$259.00 per year
only $21.58 per issue
Rent or buy this article
Prices vary by article type
Prices may be subject to local taxes which are calculated during checkout
Sikes, E. L., Allen, K. A. & Lund, D. C. Enhanced δ13C and δ18O differences between the South Atlantic and South Pacific during the last glaciation: the deep gateway hypothesis. Paleoceanography 32, 1000–1017 (2017).
Curry, W. B. & Oppo, D. W. Glacial water mass geometry and the distribution of δ13C of ΣCO2 in the western Atlantic Ocean. Paleoceanography 20, PA1017 (2005).
Wunsch, C. Determining paleoceanographic circulations, with emphasis on the Last Glacial Maximum. Quat. Sci. Rev. 22, 371–385 (2003).
Jansen, M. F. & Nadeau, L.-P. The effect of Southern Ocean surface buoyancy loss on the deep-ocean circulation and stratification. J. Phys. Oceanogr. 46, 3455–3470 (2016).
Marchitto, T. M., Lehman, S. J., Ortiz, J. D., Flückiger, J. & van Geen, A. Marine radiocarbon evidence for the mechanism of deglacial atmospheric CO2 rise. Science 316, 1456–1459 (2007).
Broecker, W. et al. Radiocarbon age of late glacial deep water from the equatorial Pacific. Paleoceanography 22, PA2206 (2007).
Okazaki, Y. et al. Deepwater formation in the North Pacific during the Last Glacial Termination. Science 329, 200–204 (2010).
Burke, A. & Robinson, L. F. The Southern Ocean’s role in carbon exchange during the last deglaciation. Science 335, 557–561 (2012).
Davies-Walczak, M. et al. Late Glacial to Holocene radiocarbon constraints on North Pacific Intermediate Water ventilation and deglacial atmospheric CO2 sources. Earth Planet. Sci. Lett. 397, 57–66 (2014).
Rose, K. A. et al. Upper-ocean-to-atmosphere radiocarbon offsets imply fast deglacial carbon dioxide release. Nature 466, 1093–1097 (2010).
Cook, M. S. & Keigwin, L. D. Radiocarbon profiles of the NW Pacific from the LGM and deglaciation: evaluating ventilation metrics and the effect of uncertain surface reservoir ages. Paleoceanography 30, 174–195 (2015).
Lund, D. C., Mix, A. C. & Southon, J. Increased ventilation age of the deep northeast Pacific Ocean during the last deglaciation. Nat. Geosci. 4, 771–774 (2011).
Sikes, E. L., Cook, M. S. & Guilderson, T. P. Reduced deep ocean ventilation in the Southern Pacific Ocean during the last glaciation persisted into the deglaciation. Earth Planet. Sci. Lett. 438, 130–138 (2016).
Jones, D. C., Ito, T., Takano, Y. & Hsu, W.-C. Spatial and seasonal variability of the air-sea equilibration timescale of carbon dioxide. Glob. Biogeochem. Cycles 28, 1163–1178 (2014).
Koeve, W., Wagner, H., Kähler, P. & Oschlies, A. 14C-age tracers in global ocean circulation models. Geosci. Model Dev. 8, 2079–2094 (2015).
Skinner, L. C., Fallon, S., Waelbroeck, C., Michel, E. & Barker, S. Ventilation of the deep Southern Ocean and deglacial CO2 rise. Science 328, 1147–1151 (2010).
Sarnthein, M., Balmer, S., Grootes, P. M. & Mudelsee, M. Planktic and benthic 14C reservoir ages for three ocean basins, calibrated by a suite of 14C plateaus in the glacial-to-deglacial Suigetsu atmospheric 14C record. Radiocarbon 57, 129–151 (2015).
Lacan, F. & Jeandel, C. Neodymium isotopes as a new tool for quantifying exchange fluxes at the continent–ocean interface. Earth Planet. Sci. Lett. 232, 245–257 (2005).
Abbott, A. N., Haley, B. A. & McManus, J. Bottoms up: sedimentary control of the deep North Pacific Ocean’s εNd signature. Geology 43, 1035–1035 (2015).
Du, J., Haley, B. A. & Mix, A. C. Neodymium isotopes in authigenic phases, bottom waters and detrital sediments in the Gulf of Alaska and their implications for paleo-circulation reconstruction. Geochim. Cosmochim. Acta 193, 14–35 (2016).
Haley, B. A., Du, J., Abbott, A.N. & McManus, J. The impact of benthic processes on rare earth element and neodymium isotope distributions in the oceans. Front. Mar. Sci. 4, 426 (2017).
Gebbie, G. & Huybers, P. The mean age of ocean waters inferred from radiocarbon observations: sensitivity to surface sources and accounting for mixing histories. J. Phys. Oceanogr. 42, 291–305 (2012).
Menviel, L. et al. Poorly ventilated deep ocean at the Last Glacial Maximum inferred from carbon isotopes: a data–model comparison study. Paleoceanography 32, 2–17 (2016).
Cuffey, K. M. et al. Deglacial temperature history of West Antarctica. Proc. Natl Acad. Sci. USA 113, 14249–14254 (2016).
WAIS Divide Project Members. Onset of deglacial warming in West Antarctica driven by local orbital forcing. Nature 500, 440–444 (2013).
Clark, P. U., McCabe, A. M., Mix, A. C. & Weaver, A. J. Rapid rise of sea level 19,000 years ago and its global implications. Science 304, 1141–1144 (2004).
Parrenin, F. et al. Synchronous change of atmospheric CO2 and Antarctic temperature during the last deglacial warming. Science 339, 1060–1063 (2013).
Marcott, S. A. et al. Centennial-scale changes in the global carbon cycle during the last deglaciation. Nature 514, 616–619 (2014).
Bereiter, B., Shackleton, S., Baggenstos, D., Kawamura, K. & Severinghaus, J. Mean global ocean temperatures during the last glacial transition. Nature 553, 39 (2018).
Schmitt, J. et al. Carbon isotope constraints on the deglacial CO2 rise from ice cores. Science 336, 711–714 (2012).
Bauska, T. K. et al. Carbon isotopes characterize rapid changes in atmospheric carbon dioxide during the last deglaciation. Proc. Natl Acad. Sci. USA 113, 3465–3470 (2016).
Anderson, R. F. et al. Wind-driven upwelling in the Southern Ocean and the deglacial rise in atmospheric CO2. Science 323, 1443–1448 (2009).
Basak, C. et al. Breakup of last glacial deep stratification in the South Pacific. Science 359, 900–904 (2018).
Talley, L. D. Freshwater transport estimates and the global overturning circulation: shallow, deep and throughflow components. Prog. Oceanogr. 78, 257–303 (2008).
Talley, L. D. Closure of the global overturning circulation through the Indian, Pacific, and Southern Oceans: schematics and transports. Oceanography 21, 80–97 (2013).
Menviel, L., England, M. H., Meissner, K. J., Mouchet, A. & Yu, J. Atlantic–Pacific seesaw and its role in outgassing CO2 during Heinrich events. Paleoceanography 29, 58–70 (2014).
Lauderdale, J. M., Williams, R. G., Munday, D. R. & Marshall, D. P. The impact of Southern Ocean residual upwelling on atmospheric CO2 on centennial and millennial timescales. Clim. Dyn. 48, 1611–1631 (2017).
Menviel, L., Mouchet, A., Meissner, K. J., Joos, F. & England, M. H. Impact of oceanic circulation changes on atmospheric δ 13CO2. Glob. Biogeochem. Cycles 29, 1944–1961 (2015).
Gray, W. R. et al. Deglacial upwelling, productivity and CO2 outgassing in the North Pacific Ocean. Nat. Geosci. 11, 340–344 (2018).
Zhao, N., Marchal, O., Keigwin, L., Amrhein, D. & Gebbie, G. A synthesis of deglacial deep-sea radiocarbon records and their (in)consistency with modern ocean ventilation. Paleoceanogr. Paleoclimatology 33, 128–151 (2018).
de la Fuente, M., Skinner, L., Calvo, E., Pelejero, C. & Cacho, I. Increased reservoir ages and poorly ventilated deep waters inferred in the glacial Eastern Equatorial Pacific. Nat. Commun. 6, 7420 (2015).
Martínez-Botí, M. A. et al. Boron isotope evidence for oceanic carbon dioxide leakage during the last deglaciation. Nature 518, 219–222 (2015).
Rae, J. W. B. et al. Deep water formation in the North Pacific and deglacial CO2 rise. Paleoceanography 29, 645–667 (2014).
Friedrich, T., Timmermann, A., Stichel, T. & Pahnke, K. Ocean circulation reconstructions from εNd: a model-based feasibility study. Paleoceanography 29, 1003–1023 (2014).
McManus, J. F., Francois, R., Gherardi, J.-M., Keigwin, L. D. & Brown-Leger, S. Collapse and rapid resumption of Atlantic meridional circulation linked to deglacial climate changes. Nature 428, 834–837 (2004).
Marzocchi, A. & Jansen, M. F. Connecting Antarctic sea ice to deep-ocean circulation in modern and glacial climate simulations. Geophys. Res. Lett. 44, 2017GL073936 (2017).
Loose, B., McGillis, W. R., Perovich, D., Zappa, C. J. & Schlosser, P. A parameter model of gas exchange for the seasonal sea ice zone. Ocean Sci 10, 17–28 (2014).
Abernathey, R. P. et al. Water-mass transformation by sea ice in the upper branch of the Southern Ocean overturning. Nat. Geosci. 9, 596–601 (2016).
Adkins, J. F., Ingersoll, A. P. & Pasquero, C. Rapid Climate Change and conditional instability of the glacial deep ocean from the thermobaric effect and geothermal heating. Quat. Sci. Rev. 24, 581–594 (2005).
Lund, D. C. et al. Enhanced East Pacific Rise hydrothermal activity during the last two glacial terminations. Science 351, 478–482 (2016).
Adkins, J. F., McIntyre, K., & Schrag, D. P. The salinity, temperature, and δ18O of the glacial deep ocean. Science 298, 1769–1773 (2002).
Zahn, R. & Mix, A. C. Benthic foraminiferal δ18O in the ocean’s temperature–salinity–density field: constraints on Ice Age thermohaline circulation. Paleoceanography 6, 1–20 (1991).
Roberts, J. et al. Evolution of South Atlantic density and chemical stratification across the last deglaciation. Proc. Natl Acad. Sci. USA 113, 514–519 (2016).
Meijers, A. J. S. The Southern Ocean in the Coupled Model Intercomparison Project phase 5. Philos. Trans. R. Soc. A 372, 20130296 (2014).
Bereiter, B. et al. Revision of the EPICA Dome C CO2 record from 800 to 600 kyr before present. Geophys. Res. Lett. 42, 542–549 (2015).
Böhm, E. et al. Strong and deep Atlantic meridional overturning circulation during the last glacial cycle. Nature 517, 73–76 (2015).
Key, R. M. et al. A global ocean carbon climatology: results from Global Data Analysis Project (GLODAP). Glob. Biogeochem. Cycles 18, GB4031 (2004).
Howe, J. N. W. et al. Antarctic intermediate water circulation in the South Atlantic over the past 25,000 years. Paleoceanography 31, 1302–1314 (2016).
Wilson, D. J., Piotrowski, A. M., Galy, A. & Clegg, J. A. Reactivity of neodymium carriers in deep sea sediments: implications for boundary exchange and paleoceanography. Geochim. Cosmochim. Acta 109, 197–221 (2013).
Blaser, P. et al. Extracting foraminiferal seawater Nd isotope signatures from bulk deep sea sediment by chemical leaching. Chem. Geol. 439, 189–204 (2016).
Molina-Kescher, M., Frank, M. & Hathorne, E. Nd and Sr isotope compositions of different phases of surface sediments in the South Pacific: extraction of seawater signatures, boundary exchange, and detrital/dust provenance. Geochem. Geophys. Geosystems 15, 3502–3520 (2014).
Wu, Q. et al. Neodymium isotopic composition in foraminifera and authigenic phases of the South China Sea sediments: implications for the hydrology of the North Pacific Ocean over the past 25 kyr. Geochem. Geophys. Geosystems 16, 3883–3904 (2015).
Tachikawa, K. et al. The large-scale evolution of neodymium isotopic composition in the global modern and Holocene ocean revealed from seawater and archive data. Chem. Geol. 457, 131–148 (2017).
Muratli, J. M., McManus, J., Mix, A. & Chase, Z. Dissolution of fluoride complexes following microwave-assisted hydrofluoric acid digestion of marine sediments. Talanta 89, 195–200 (2012).
O’Nions, R. K., Carter, S. R., Evensen, N. M. & Hamilton, P. J. Geochemical and cosmochemical applications of Nd isotope analysis. Annu. Rev. Earth Planet. Sci. 7, 11–38 (1979).
Tanaka, T. et al. JNdi-1: a neodymium isotopic reference in consistency with LaJolla neodymium. Chem. Geol. 168, 279–281 (2000).
Weis, D. et al. High-precision isotopic characterization of USGS reference materials by TIMS and MC-ICP-MS. Geochem. Geophys. Geosystems 7, Q08006 (2006).
Praetorius, S. K. et al. North Pacific deglacial hypoxic events linked to abrupt ocean warming. Nature 527, 362–366 (2015).
Praetorius, S. K. & Mix, A. C. Synchronization of North Pacific and Greenland climates preceded abrupt deglacial warming. Science 345, 444–448 (2014).
Haslett, J. & Parnell, A. A simple monotone process with application to radiocarbon-dated depth chronologies. J. R. Stat. Soc. Ser. C Appl. Stat. 57, 399–418 (2008).
Abbott, A. N., Haley, B. A., McManus, J. & Reimers, C. E. The sedimentary flux of dissolved rare earth elements to the ocean. Geochim. Cosmochim. Acta 154, 186–200 (2015).
Tachikawa, K., Athias, V. & Jeandel, C. Neodymium budget in the modern ocean and paleo-oceanographic implications. J. Geophys. Res. Oceans 108, 3254 (2003).
Arsouze, T., Dutay, J.-C., Lacan, F. & Jeandel, C. Reconstructing the Nd oceanic cycle using a coupled dynamical–biogeochemical model. Biogeosciences 6, 2829–2846 (2009).
Rempfer, J., Stocker, T. F., Joos, F., Dutay, J.-C. & Siddall, M. Modelling Nd-isotopes with a coarse resolution ocean circulation model: sensitivities to model parameters and source/sink distributions. Geochim. Cosmochim. Acta 75, 5927–5950 (2011).
de Lavergne, C., Madec, G., Roquet, F., Holmes, R. M. & McDougall, T. J. Abyssal ocean overturning shaped by seafloor distribution. Nature 551, 181–186 (2017).
Ferrari, R., Mashayek, A., McDougall, T. J., Nikurashin, M. & Campin, J.-M. Turning ocean mixing upside down. J. Phys. Oceanogr. 46, 2239–2261 (2016).
de Lavergne, C., Madec, G., Le Sommer, J., Nurser, A. J. G. & Naveira Garabato, A. C. On the consumption of Antarctic Bottom Water in the abyssal ocean. J. Phys. Oceanogr. 46, 635–661 (2015).
Abbott, A. N., Haley, B. A. & McManus, J. The impact of sedimentary coatings on the diagenetic Nd flux. Earth Planet. Sci. Lett. 449, 217–227 (2016).
Jones, K. M., Khatiwala, S. P., Goldstein, S. L., Hemming, S. R. & van de Flierdt, T. Modeling the distribution of Nd isotopes in the oceans using an ocean general circulation model. Earth Planet. Sci. Lett. 272, 610–619 (2008).
Howe, J. N. W., Piotrowski, A. M. & Rennie, V. C. F. Abyssal origin for the early Holocene pulse of unradiogenic neodymium isotopes in Atlantic seawater. Geology 44, 831–834 (2016).
Roberts, N. L. & Piotrowski, A. M. Radiogenic Nd isotope labeling of the northern NE Atlantic during MIS 2. Earth Planet. Sci. Lett. 423, 125–133 (2015).
Talley, L. D. Shallow, intermediate, and deep overturning components of the global heat budget. J. Phys. Oceanogr. 33, 530–560 (2003).
Lambelet, M. et al. Neodymium isotopic composition and concentration in the western North Atlantic Ocean: results from the GEOTRACES GA02 section. Geochim. Cosmochim. Acta 177, 1–29 (2016).
Praetorius, S. et al. Interaction between climate, volcanism, and isostatic rebound in Southeast Alaska during the last deglaciation. Earth Planet. Sci. Lett. 452, 79–89 (2016).
Menard, H. W. & Smith, S. M. Hypsometry of ocean basin provinces. J. Geophys. Res. 71, 4305–4325 (1966).
McLennan, S. M., Hemming, S., McDaniel, D. K. & Hanson, G. N. Geochemical approaches to sedimentation, provenance, and tectonics. Geol. Soc. Am. Spec. Pap. 284, 21–40 (1993).
Ziegler, C. L., Murray, R. W., Hovan, S. A. & Rea, D. K. Resolving eolian, volcanogenic, and authigenic components in pelagic sediment from the Pacific Ocean. Earth Planet. Sci. Lett. 254, 416–432 (2007).
Dunlea, A. G. et al. Dust, volcanic ash, and the evolution of the South Pacific Gyre through the Cenozoic. Paleoceanography 30, 1078–1099 (2015).
Hu, R. et al. Neodymium isotopic evidence for linked changes in Southeast Atlantic and Southwest Pacific circulation over the last 200 kyr. Earth Planet. Sci. Lett. 455, 106–114 (2016).
Noble, T. L., Piotrowski, A. M. & McCave, I. N. Neodymium isotopic composition of intermediate and deep waters in the glacial southwest Pacific. Earth Planet. Sci. Lett. 384, 27–36 (2013).
Elderfield, H. et al. Evolution of ocean temperature and ice volume through the Mid-Pleistocene Climate Transition. Science 337, 704–709 (2012).
Molina-Kescher, M. et al. Reduced admixture of North Atlantic Deep Water to the deep central South Pacific during the last two glacial periods. Paleoceanography 31, 651–668 (2016).
We thank J. Muratli for assistance with bulk sediment digestion and A. Ungerer for assistance with elemental and isotope analyses at the W. M. Keck Collaboratory for Plasma Spectrometry at Oregon State University. We thank the OSU Marine and Geology Repository and the International Ocean Discover Program for providing sediment samples. IODP-U1418 samples were provided by C. Belanger. This study was supported by NSF grant MGG-1357529 (A.C.M. and B.A.H.).
The authors declare no competing interests.
Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
About this article
Cite this article
Du, J., Haley, B.A., Mix, A.C. et al. Flushing of the deep Pacific Ocean and the deglacial rise of atmospheric CO2 concentrations. Nature Geosci 11, 749–755 (2018). https://doi.org/10.1038/s41561-018-0205-6
This article is cited by
Indian Ocean glacial deoxygenation and respired carbon accumulation during mid-late Quaternary ice ages
Nature Communications (2023)
Nature Geoscience (2023)
Nature Reviews Earth & Environment (2023)
Nature Communications (2022)
Nature Communications (2022)