Tracking the Indian Ocean source of barium

Science Highlights

5 September 2013

Intermediate waters of the Bay of Bengal can be a significant source of dissolved barium (Ba) to the Indian Ocean. This is the conlusion of an extensive study of the dissolved Ba distribution along a north-south section in the Bay of Bengal conducted by Satinder Pal Singh and co-workers. At steady state, researchers found that the annual Ba influx from the Ganga­-Brahmaputra river system to the surface waters seems to be balanced through its removal via sinking particulates, resulting in no lateral outflow of dissolved Ba from the Ganga­-Brahmaputra to the Indian Ocean through these surface waters. However, most of this sinking particulate Ba (~95%) is regenerated in the intermediate waters ~100-­500 m. Therefore, frequently ventilated intermediate waters of the Bay of Bengal, receiving a large input of dissolved Ba through particle remineralization can be a significant source of dissolved Ba to the Indian Ocean.

13 Pal singh 2

Figure: Locations of seawater profile samples (depth profiles collected in this study are represented by red circles whereas white squares during the GEOSECS programme). The yellow triangles are locations of the sediment cores 4032 and 4040. The box is an enlarged view of the locations of shelf stations. Click here to see figure larger.

 

Reference:

Satinder Pal Singh, Sunil Kumar Singh, Ravi Bhushan (2013), Internal cycling of dissolved barium in water column of the Bay of Bengal, Marine Chemistry 154, p. 12-23 DOI:10.1016/j.marchem.2013.04.013. Click here to access the paper.

Latest highlights

Continuous record of the Antarctic Circumpolar Current latitude over the last glacial-interglacial cycles

The meridional positions of the oceanic fronts separating subtropical and Antarctic waters are key to constraining the mechanisms that drive the degassing of deeply-stored CO2 at the end of the glacial periods…

23 Million Years of iron sources reconstructed in the Northwest Pacific Ocean using iron isotopes in a ferromanganese crust

Using iron isotopes and elemental records, Chu and co-workers analysed an iron-manganese crust recovered from the Hongyan Seamount, and reconstructed the sources of dissolved Fe to the Northwest Pacific Ocean…

Variability of the past deep-water masses in the Arabian Sea over the last 41ka

Shukla and colleagues propose a high-resolution authigenic ƐNd record measured from a sediment core located in the eastern Arabian Sea…

Arctic outflows to Davis Strait and the Labrador Sea traced by radionuclide distributions

This study demonstrates that Arctic outflows through the Canadian Arctic Archipelago play a much more significant role than previously recognised.

Rechercher