Where, how and which trace elements are released from dust at the sea surface?

Science Highlights

25 January 2018

Alex Baker and Tim Jickells (2017, see reference below) propose to answer to this question thanks to analysis of aerosols collected in the framework of the Atlantic Meridional Transect (AMT). They established the soluble concentrations of a range of trace metals (iron, aluminium, manganese, titanium, zinc, vanadium, nickel and copper) and major ions. They reveal much higher inputs to the North Atlantic Ocean compared to the South Atlantic Ocean, reflecting stronger land based emission sources in the Northern Hemisphere. Comparison of these inputs with the surface water contents of the same trace metals compiled in the GEOTRACES intermediate data product show surprising features that you will discover if you read this paper…

18 Baker lowFigures: (A) Approximate tracks of the AMT cruises (dots and triangles) and general flow directions of the seven major atmospheric transport routes encountered during the cruises (arrows). Abbreviations for the air transport regimes are: continental Europe (EUR), North Africa including the Sahara and Sahel: (SAH), Southern Africa impacted by biomass burning emissions (SAB), Southern Africa not impacted by biomass burning (SAF), South America (SAM), remote North or South Atlantic i.e. not crossing land for at least 5 days prior to collection (RNA and RSA respectively). (B) Box and whisker plots showing the variations in the concentrations of iron, aluminium, manganese, titanium, zinc, vanadium, nickel and copper with air transport/source type for the AMT transect. They reveal much higher inputs to the North Atlantic Ocean, reflecting stronger land based emission sources in the Northern Hemisphere. Please click here to view the figure larger. (Figures modified from Progress in Oceanography)

Reference:

Baker, A. R., & Jickells, T. D. (2017). Atmospheric deposition of soluble trace elements along the Atlantic Meridional Transect (AMT). Progress in Oceanography, 158, 41–51. http://doi.org/10.1016/j.pocean.2016.10.002

Latest highlights

Regional zinc cycling in the Indian Ocean

Chinni and his colleagues present dissolved zinc distributions across the Arabian Sea, Bay of Bengal and southern tropical Indian Ocean…

Contrasting organic carbon  remineralisation rates revealed by particulate excess barium in the North Pacific and South China Sea

Yuan and co-workers quantify organic carbon remineralisation in the twilight zone of the China Sea using particulate excess barium as a proxy…

Sedimentary controls on seawater nickel distributions and nickel isotope compositions: a two steps study

Nickel isotopic mass balance in the ocean stands among the less understood so far…

23 million years of productivity reconstructed in the Central Pacific Ocean using past and modern proxies

Using diverse geochemical proxies, Chu and colleagues analysed an iron–manganese crust to reconstruct central Pacific productivity over the past 23 million years.

Rechercher