The impact of the different sources of iron on the ability of the ocean to absorb atmospheric carbon dioxide: reversing the paradigm?

Using model simulations, Tagliabue and co-authors (2014, see reference below) tested the sensitivity of the ocean to absorb the atmospheric carbon dioxide (CO2) in response to variable supply of iron. They found that while atmospheric CO2 is sensitive to sedimentary iron input, it is relatively insensitive to dust and hydrothermal iron input.

The weak reaction of atmospheric CO2 to dust input, which completely change previous paradigms, is due to the fact that dust is not the major iron input to the remote Southern Ocean, while sediment supply plays an overwhelming role in regulating export production in this oceanic area.

This works also shows that while hydrothermal input is crucial in governing the iron inventory for ~25% of the ocean, it remains restricted to the deep ocean, and has small effect on atmospheric CO2.

14 Tagliabue l

Figure: A map of the dominant iron source in controlling the dissolved iron inventory (upper) and biological carbon export flux (lower panel). Please click here to view the figure larger.

 

Reference:

Tagliabue, A., Aumont, O., & Bopp, L. (2014). The impact of different external sources of iron on the global carbon cycle. Geophysical Research Letters, 41(3), 920–926. doi:10.1002/2013GL059059. Click here to access the paper.

Latest highlights

Science Highlights

Controls of cadmium-phosphate systematic unraveled by Neural Networks and Ocean Circulation Inverse Model

Roshan and DeVries explore the similarities and contrasts between oceanic cadmium and phosphate cycles using an Artificial Neural Network mapping technique and Ocean Circulation Inverse Model.

23.06.2021

Science Highlights

Retreat of large marine-terminating glaciers may increase iron supply to surface waters

The findings demonstrate that glacial retreat and loss of ice-shelves may potentially result in increases in dissolved Fe supply to surface waters downstream of large marine terminating glaciers in future.

31.05.2021

Science Highlights

A new and more quantitative atlas of the deep-sea burial fluxes of major and trace elements

Among other findings, authors find that the new opal flux is roughly a factor of two increase over previous estimates having important implications for the global silicon cycle.

21.05.2021

Science Highlights

Updated compilation of the global continental and marine lithogenic neodymium isotopic measurements

This new compilation and gridded datasets offer a concrete way forward to improve the application of neodymium isotopes as a useful tracer of ocean circulation.

05.05.2021

Rechercher