IDEAS home Printed from https://ideas.repec.org/a/nat/natcom/v10y2019i1d10.1038_s41467-019-12549-z.html
   My bibliography  Save this article

Marine nitrogen fixers mediate a low latitude pathway for atmospheric CO2 drawdown

Author

Listed:
  • Pearse J. Buchanan

    (University of Liverpool
    University of Tasmania
    CSIRO Oceans and Atmosphere, CSIRO Marine Laboratories
    ARC Centre of Excellence in Climate System Science)

  • Zanna Chase

    (University of Tasmania)

  • Richard J. Matear

    (CSIRO Oceans and Atmosphere, CSIRO Marine Laboratories
    ARC Centre of Excellence in Climate Extremes)

  • Steven J. Phipps

    (University of Tasmania)

  • Nathaniel L. Bindoff

    (University of Tasmania
    CSIRO Oceans and Atmosphere, CSIRO Marine Laboratories
    ARC Centre of Excellence in Climate Extremes
    Antarctic Climate and Ecosystems Cooperative Research Centre)

Abstract

Roughly a third (~30 ppm) of the carbon dioxide (CO2) that entered the ocean during ice ages is attributed to biological mechanisms. A leading hypothesis for the biological drawdown of CO2 is iron (Fe) fertilisation of the high latitudes, but modelling efforts attribute at most 10 ppm to this mechanism, leaving ~20 ppm unexplained. We show that an Fe-induced stimulation of dinitrogen (N2) fixation can induce a low latitude drawdown of 7–16 ppm CO2. This mechanism involves a closer coupling between N2 fixers and denitrifiers that alleviates widespread nitrate limitation. Consequently, phosphate utilisation and carbon export increase near upwelling zones, causing deoxygenation and deeper carbon injection. Furthermore, this low latitude mechanism reproduces the regional patterns of organic δ15N deposited in glacial sediments. The positive response of marine N2 fixation to dusty ice age conditions, first proposed twenty years ago, therefore compliments high latitude changes to amplify CO2 drawdown.

Suggested Citation

  • Pearse J. Buchanan & Zanna Chase & Richard J. Matear & Steven J. Phipps & Nathaniel L. Bindoff, 2019. "Marine nitrogen fixers mediate a low latitude pathway for atmospheric CO2 drawdown," Nature Communications, Nature, vol. 10(1), pages 1-10, December.
    • Handle: RePEc:nat:natcom:v:10:y:2019:i:1:d:10.1038_s41467-019-12549-z
    DOI: 10.1038/s41467-019-12549-z
    as

    Download full text from publisher

    File URL: https://www.nature.com/articles/s41467-019-12549-z
    File Function: Abstract
    Download Restriction: no
    File URL: https://libkey.io/10.1038/s41467-019-12549-z?utm_source=ideas
    LibKey link: if access is restricted and if your library uses this service, LibKey will redirect you to where you can use your library subscription to access this item
    ---><---

    More about this item

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:nat:natcom:v:10:y:2019:i:1:d:10.1038_s41467-019-12549-z. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    We have no bibliographic references for this item. You can help adding them by using this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: Sonal Shukla or Springer Nature Abstracting and Indexing (email available below). General contact details of provider: http://www.nature.com .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.