When lateral advective transport explains between 80 and 100% of the dissolved aluminium distribution

Artigue and colleagues (2021, see reference below) present new dissolved aluminum (dAl) data from the 2017 GEOTRACES process study GApr08 along 22°N in the subtropical North Atlantic Ocean. The originality of this study is that the authors used a model that does not neglect advection in the surface, and the results of an optimum multiparameter analysis below 200 m to separate the component of the dAl signal derived from water mass transport from its biogeochemical component. Thanks to this approach Artigue and co-authors have shown that while the dAl distribution is usually considered to be dominated by atmospheric dust input and removal by particle scavenging, water mass transport plays a major role from the surface to the sea floor and cannot be neglected in this area. At the surface, advection and dust dissolution are equally important dAl sources. Below 200 m, again a major role is played by water mass transport, while dissolved/particle interactions act as a moderate dAl sink from 200 to 1000 m and as a moderate dAl source from 1000 to 5500 m (grey shaded area in the figure below).

Overall, these results evidence that the effect of advection cannot be neglected in areas where a conjunction of significant horizontal dAl gradients and significant horizontal currents is found.

Figure (modified from Artigue et al., 2021): Mean measured dissolved aluminum concentration (dAl) profile (blue dots), mean water mass transport dAl profile (red dots), and mean ‘biogeochemical’ dAl profile (difference between the blue and red curves, white dots) of the seven stations of GApr08 cruise. Error bars are standard errors from the 7 station mean.


Artigue, L., Wyatt, N. J., Lacan, F., Mahaffey, C., & Lohan, M. C. (2021). The importance of water mass transport and dissolved‐particle interactions on the aluminum cycle in the subtropical North Atlantic. Global Biogeochemical Cycles, e2020GB006569. https://doi.org/10.1029/2020GB006569

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.


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.


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.


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.