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Increased nutrient supply to the Southern Ocean during the Holocene and its implications for the pre-industrial atmospheric CO2 rise

Abstract

A rise in the atmospheric CO2 concentration of ~20 parts per million over the course of the Holocene has long been recognized as exceptional among interglacials and is in need of explanation. Previous hypotheses involved natural or anthropogenic changes in terrestrial biomass, carbonate compensation in response to deglacial outgassing of oceanic CO2, and enhanced shallow water carbonate deposition. Here, we compile new and previously published fossil-bound nitrogen isotope records from the Southern Ocean that indicate a rise in surface nitrate concentration through the Holocene. When coupled with increasing or constant export production, these data suggest an acceleration of nitrate supply to the Southern Ocean surface from underlying deep water. This change would have weakened the ocean’s biological pump that stores CO2 in the ocean interior, possibly explaining the Holocene atmospheric CO2 rise. Over the Holocene, the circum-North Atlantic region cooled, and the formation of North Atlantic Deep Water appears to have slowed. Thus, the ‘seesaw’ in deep ocean ventilation between the North Atlantic and the Southern Ocean that has been invoked for millennial-scale events, deglaciations and the last interglacial period may have also operated, albeit in a more gradual form, over the Holocene.

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Fig. 1: Sediment core and deep sea coral locations relative to austral summer surface nitrate concentrations and oceanic fronts.
Fig. 2: Holocene records of fossil-bound δ15N and biogenic opal flux from the Southern Ocean, compared with atmospheric CO2 and with climate- and circulation-related records from the Northern Hemisphere.

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References

  1. Waugh, D. W. Changes in the ventilation of the southern oceans. Philos. Trans. R. Soc. A 372, 20130269 (2014).

    Google Scholar 

  2. Marcott, S. A., Shakun, J. D., Clark, P. U. & Mix, A. C. A reconstruction of regional and global temperature for the past 11,300 years. Science 339, 1198–1201 (2013).

    Google Scholar 

  3. Indermühle, A. et al. Holocene carbon-cycle dynamics based on CO2 trapped in ice at Taylor Dome, Antarctica. Nature 398, 121–126 (1999).

    Google Scholar 

  4. Ruddiman, W. F. The Anthropogenic greenhouse era began thousands of years ago. Clim. Change 61, 261–293 (2003).

    Google Scholar 

  5. Broecker, W. S., Lynch-Stieglitz, J., Clark, E., Hajdas, I. & Bonani, G. What caused the atmosphere’s CO2 content to rise during the last 8000 years? Geochem. Geophys. Geosyst. 2, 2001GC000177 (2001).

    Google Scholar 

  6. Ridgwell, A. J., Watson, A. J., Maslin, M. A. & Kaplan, J. O. Implications of coral reef buildup for the controls on atmospheric CO2 since the Last Glacial Maximum. Paleoceanography 18, 1083 (2003).

    Google Scholar 

  7. Sunda, W. G. & Huntsman, S. A. Interrelated influence of iron, light and cell size on marine phytoplankton growth. Nature 390, 389–392 (1997).

    Google Scholar 

  8. Sarmiento, J. L. & Toggweiler, J. R. A new model for the role of the oceans in determining atmospheric p CO2. Nature 308, 621–624 (1984).

    Google Scholar 

  9. Toggweiler, J. R., Russell, J. L. & Carson, S. R. Midlatitude westerlies, atmospheric CO2, and climate change during the ice ages. Paleoceanography 21, PA2005 (2006).

    Google Scholar 

  10. Moreno, P. I., François, J. P., Moy, C. M. & Villa-Martínez, R. Covariability of the southern westerlies and atmospheric CO2 during the Holocene. Geology 38, 727–730 (2010).

    Google Scholar 

  11. Anderson, R. F. et al. Wind-driven upwelling in the Southern Ocean and the deglacial rise in atmospheric CO2. Science 323, 1443–1448 (2009).

    Google Scholar 

  12. Denton, G. H. et al. The Last Glacial termination. Science 328, 1652–1656 (2010).

    Google Scholar 

  13. Lamy, F. et al. Holocene changes in the position and intensity of the southern westerly wind belt. Nat. Geosci. 3, 695–699 (2010).

    Google Scholar 

  14. Martinez-Garcia, A. et al. Iron fertilization of the Subantarctic Ocean during the last ice age. Science 343, 1347–1350 (2014).

    Google Scholar 

  15. Studer, A. S. et al. Antarctic zone nutrient conditions during the last two glacial cycles. Paleoceanography 30, 2014PA002745 (2015).

    Google Scholar 

  16. Wang, X. T. et al. Deep-sea coral evidence for lower Southern Ocean surface nitrate concentrations during the last ice age. Proc. Natl Acad. Sci. USA 114, 3352–3357 (2017).

    Google Scholar 

  17. Francois, R. et al. Contribution of Southern Ocean surface-water stratification to low atmospheric CO2 concentrations during the last glacial period. Nature 389, 929–935 (1997).

    Google Scholar 

  18. Dezileau, L., Bareille, G. & Reyss, J. L. The 231Pa/230Th ratio as a proxy for past changes in opal fluxes in the Indian sector of the Southern Ocean. Mar. Chem. 81, 105–117 (2003).

    Google Scholar 

  19. Robinson, R. S. et al. A review of nitrogen isotopic alteration in marine sediments. Paleoceanography 27, PA4203 (2012).

    Google Scholar 

  20. Ren, H. et al. Impact of glacial/interglacial sea level change on the ocean nitrogen cycle. Proc. Natl Acad. Sci. USA 114, E6759–E6766 (2017).

    Google Scholar 

  21. Shemesh, A., Macko, S. A., Charles, C. D. & Rau, G. H. Isotopic evidence for reduced productivity in the glacial Southern. Ocean. Sci. 262, 407–410 (1993).

    Google Scholar 

  22. Sigman, D. M., Altabet, M. A., Francois, R., McCorkle, D. C. & Gaillard, J.-F. The isotopic composition of diatom-bound nitrogen in Southern Ocean sediments. Paleoceanography 14, 118–134 (1999).

    Google Scholar 

  23. Robinson, R. S., Brunelle, B. G. & Sigman, D. M. Revisiting nutrient utilization in the glacial Antarctic: evidence from a new method for diatom-bound N isotopic analysis. Paleoceanography 19, PA3001 (2004).

    Google Scholar 

  24. Studer, A. S., Ellis, K. K., Oleynik, S., Sigman, D. M. & Haug, G. H. Size-specific opal-bound nitrogen isotope measurements in North Pacific sediments. Geochim. Cosmochim. Acta 120, 179–194 (2013).

    Google Scholar 

  25. Horn, M. G., Beucher, C. P., Robinson, R. S. & Brzezinski, M. A. Southern Ocean nitrogen and silicon dynamics during the last deglaciation. Earth Plant. Sci. Lett. 310, 334–339 (2011).

    Google Scholar 

  26. Robinson, R. S. & Sigman, D. M. Nitrogen isotopic evidence for a poleward decrease in surface nitrate within the ice age Antarctic. Quat. Sci. Rev. 27, 1076–1090 (2008).

    Google Scholar 

  27. Marconi, D. et al. Tropical dominance of N2 fixation in the North Atlantic Ocean. Glob. Biogeochem. Cycles 31, 1608–1623 (2017).

    Google Scholar 

  28. Rafter, P. A., DiFiore, P. J. & Sigman, D. M. Coupled nitrate nitrogen and oxygen isotopes and organic matter remineralization in the Southern and Pacific Oceans. J. Geophys. Res. 118, 4781–4794 (2013).

    Google Scholar 

  29. Sigman, D. M., Altabet, M. A., McCorkle, D. C., François, R. & Fischer, G. The δ15N of nitrate in the Southern Ocean: consumption of nitrate in surface waters. Glob. Biogeochem. Cycles 13, 1149–1166 (1999).

    Google Scholar 

  30. Galbraith, E. D. et al. The acceleration of oceanic denitrification during deglacial warming. Nat. Geosci. 6, 579–584 (2013).

    Google Scholar 

  31. Lambert, F. et al. Dust–climate couplings over the past 800,000 years from the EPICA Dome C ice core. Nature 452, 616–619 (2008).

    Google Scholar 

  32. Anderson, R. F. et al. Biological response to millennial variability of dust and nutrient supply in the Subantarctic South Atlantic Ocean. Philos. Trans. R. Soc. A 372, 20130054 (2014).

    Google Scholar 

  33. Meckler, A. N. et al. Deglacial pulses of deep-ocean silicate into the subtropical North Atlantic Ocean. Nature 495, 495–498 (2013).

    Google Scholar 

  34. Marshall, J. & Speer, K. Closure of the meridional overturning circulation through Southern Ocean upwelling. Nat. Geosci. 5, 171–180 (2012).

    Google Scholar 

  35. Wolfe, C. L. & Cessi, P. What sets the strength of the middepth stratification and overturning circulation in eddying ocean models? J. Phys. Oceanogr. 40, 1520–1538 (2010).

    Google Scholar 

  36. Gnanadesikan, A. A simple predictive model for the structure of the oceanic pycnocline. Science 283, 2077–2079 (1999).

    Google Scholar 

  37. Keeling, R. F. & Visbeck, M. Antarctic stratification and glacial CO2. Nature 412, 605–606 (2001).

    Google Scholar 

  38. Hain, M. P., Sigman, D. M. & Haug, G. H. Carbon dioxide effects of Antarctic stratification, North Atlantic Intermediate Water formation, and subantarctic nutrient drawdown during the last ice age: diagnosis and synthesis in a geochemical box model. Glob. Biogeochem. Cycles 24, GB4023 (2010).

    Google Scholar 

  39. Schmitt, J. et al. Carbon isotope constraints on the deglacial CO2 rise from ice cores. Science 336, 711–714 (2012).

    Google Scholar 

  40. Burke, A. & Robinson, L. F. The Southern Ocean’s role in carbon exchange during the last deglaciation. Science 335, 557–561 (2012).

    Google Scholar 

  41. Yu, J. et al. Loss of carbon from the deep sea since the last glacial maximum. Science 330, 1084–1087 (2010).

    Google Scholar 

  42. Broecker, W. S. & Peng, T.-H. The role of CaCO3 compensation in the glacial to interglacial atmospheric CO2 change. Glob. Biogeochem. Cycles 1, 15–29 (1987).

    Google Scholar 

  43. Goodwin, P., Oliver, K. I. C. & Lenton, T. M. Observational constraints on the causes of Holocene CO2 change. Glob. Biogeochem. Cycles 25, GB2011 (2011).

    Google Scholar 

  44. Brovkin, V. et al. Comparative carbon cycle dynamics of the present and last interglacial. Quat. Sci. Rev. 137, 15–32 (2016).

    Google Scholar 

  45. Thornalley, D. J. R. et al. Long-term variations in Iceland–Scotland overflow strength during the Holocene. Clim. Past 9, 2073–2084 (2013).

    Google Scholar 

  46. Hoogakker, B. A. A. et al. Dynamics of North Atlantic Deep Water masses during the Holocene. Paleoceanography 26, PA4214 (2011).

    Google Scholar 

  47. Kissel, C., Van Toer, A., Laj, C., Cortijo, E. & Michel, E. Variations in the strength of the North Atlantic bottom water during Holocene. Earth Planet. Sci. Lett. 369–370, 248–259 (2013).

    Google Scholar 

  48. Broecker, W. S. Paleocean circulation during the last deglaciation: a bipolar seesaw? Paleoceanography 13, 119–121 (1998).

    Google Scholar 

  49. Ruddiman, W. F. et al. Late Holocene climate: natural or anthropogenic? Rev. Geophys. 54, 93–118 (2016).

    Google Scholar 

  50. Liu, Z. et al. The Holocene temperature conundrum. Proc. Natl Acad. Sci. USA 111, E3501–E3505 (2014).

    Google Scholar 

  51. Orsi, A. H., Whitworth, T. III & Nowlin, W. D. Jr On the meridional extent and fronts of the Antarctic Circumpolar Current. Deep-Sea Res. I 42, 641–673 (1995).

    Google Scholar 

  52. 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).

    Google Scholar 

  53. Knapp, A. N., Sigman, D. M. & Lipschultz, F. N isotopic composition of dissolved organic nitrogen and nitrate at the Bermuda Atlantic time series study site. Glob. Biogeochem. Cycles 19, GB1018 (2005).

    Google Scholar 

  54. Weigand, M. A., Foriel, J., Barnett, B., Oleynik, S. & Sigman, D. M. Updates to instrumentation and protocols for isotopic analysis of nitrate by the denitrifier method. Rapid Commun. Mass Spectrom. 30, 1365–1383 (2016).

    Google Scholar 

  55. Mortlock, R. A. & Froelich, P. N. A simple method for the rapid determination of biogenic opal in pelagic marine sediments. Deep-Sea Res 36, 1415–1426 (1989).

    Google Scholar 

  56. François, R., Frank, M., Rutgers van der Loeff, M. M. & Bacon, M. P. 230Th normalization: an essential tool for interpreting sedimentary fluxes during the late Quaternary. Paleoceanography 19, PA1018 (2004).

    Google Scholar 

  57. Bronk Ramsey, C. Bayesian analysis of radiocarbon dates. Radiocarbon 51, 337–360 (2009).

    Google Scholar 

  58. Bronk Ramsey, C. & Lee, S. Recent and planned developments of the Program OxCal. Radiocarbon 55, 720–730 (2013).

    Google Scholar 

  59. Key, R. M. et al. A global ocean carbon climatology: results from Global Data Analysis Project (GLODAP). Glob. Biogeochem. Cycles 18, GB4031 (2004).

    Google Scholar 

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Acknowledgements

This study was supported by Swiss NSF grant PBEZP2_145695 to A.S.S., US NSF grants 1401489 and 1234664 to D.M.S., Swiss NSF grant PZ00P2_142424 to A.M.-G., grants PP00P2-144811 and PP00P2_172915 to S.L.J., by the Deutsche Forschungsgemeinschaft through grant Li1815/4 to J.A.L., by funding from the Swedish Research Council VR-349-2012-6278 to E.M., from the Natural Environment Research Council NE/N003861/1 to L.F.R., and from the French INSU/LEFE Indien Sud to A.M. This research was also supported by ExxonMobil through the Andlinger Center for Energy and the Environment at Princeton University and by the Grand Challenges Program of Princeton University. Cores MD11-3353 and MD12-3396CQ were retrieved during Indien Sud oceanographic cruises (A.M.) and we express our thanks to the crew of the R/V Marion Dufresne as well as the French Polar Institute (IPEV). The authors thank K. Hendry, M. Palmer and B. Heinz for their valuable input, and X. Crosta for his help with diatom species identification.

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A.S.S., D.M.S., A.M.-G. and G.H.H. designed the study. A.S.S. performed the δ15Ndb analyses and wrote the first draft of the manuscript with D.M.S., A.M.-G. and G.H.H. L.M.T., S.L.J. and J.A.L. contributed the 230Th-normalized opal flux data. E.M. and A.M. provided access to the sediment cores and measured the radiocarbon ages for the construction of the age model. L.F.R. and J.F.A. recovered the corals, and X.T.W. generated the coral-bound δ15N data. All authors contributed to the interpretation of the data and provided input to the final manuscript.

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Correspondence to Anja S. Studer.

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Studer, A.S., Sigman, D.M., Martínez-García, A. et al. Increased nutrient supply to the Southern Ocean during the Holocene and its implications for the pre-industrial atmospheric CO2 rise. Nature Geosci 11, 756–760 (2018). https://doi.org/10.1038/s41561-018-0191-8

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