Coupling and decoupling of barium and radium-226 along the GEOVIDE GEOTRACES section

Because radium-226 (226Ra) and barium (Ba) are both alkaline earth metals and thus display similar chemical behaviours, studying their fate in contrasting environments is of prime interest. With this aim, Le Roy and co-workers (2018, see reference below) realised a high resolution description of the distribution of these tracers along the GEOVIDE section (GA01, see […]

Sep / 04 / 2018

High mesopelagic carbon remineralization traced by particulate biogenic barium in the North Atlantic Ocean

The high resolution section of particulate “excess Ba” (Baxs) measured by Lemaitre and co-authors (2018, see reference below) along the GEOVIDE GA1 section (R/V Pourquoi Pas? spring 2014) confirmed the ability of this parameter as proxy of the particulate organic carbon (POC) remineralization. Despite their importance for the biological pump quantification, POC remineralization data are […]

May / 28 / 2018

Barium isotope measurements help constraining the oceanic barium cycle

Hsieh and Henderson (2017, see reference below) propose a compilation of the oceanic barium (Ba) concentrations together with its isotopic profiles measured so far. Their review covers the main oceanic basins, comparing data obtained in the North and South Atlantic, North Pacific and the Southern Oceans. Their main conclusions are: near-surface Ba isotope values are […]

Oct / 19 / 2017

Solute-particle interactions and the enhanced dissolved barium flux from the Ganga River estuary

Dissolved and particulate barium (Ba) were investigated in samples that were collected in six periods of contrasting water discharge over two years (2012 and 2013) by Saumik and Dalai (2016, see reference below) in the Ganga (Hooghly) River estuary. The authors thoroughly documented anthropogenic sources and submarine groundwater discharges, which account for less than 2% […]

Nov / 16 / 2016

New insights into global barium cycling from the first barium isotope data for seawater

A new method developed by Horner and co-workers (2015, see reference below) allows for the determination of dissolved barium (Ba) isotopic compositions in seawater using nanogram quantities of Ba. The formation of BaSO4 (barite) in open ocean seawater is largely driven by the microbial remineralization of sinking organic matter. By analysing a 4500 m depth […]

Nov / 16 / 2015

Tracking the Indian Ocean source of barium

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 […]

Sep / 05 / 2013

Results from the GEOTRACES cruise section GIPY11

An interesting comparison of data of dissolved barium (Ba) and data of dissolved aluminium (Al) and silicate (Si) collected onboard the GEOTRACES cruise GIPY11 (ARK-XXII/2 Polarstern expedition) is presented in the article of Roeske and colleagues (Roeske et al, 2012). This comparison is used to distinguish between signals produced by the regeneration of sinking particles […]

Jul / 04 / 2012