Radium

Environmental changes in the Arctic Ocean are occurring now!

This is what reveals the first full transarctic section of radium-228 (228Ra) in surface waters measured during Arctic cruises along GEOTRACES transects GN04 (cruise PS94) and GN01 (cruise HLY1502) proposed by Rutgers van der Loeff and colleagues (2018, see reference below). 228Ra activities in the central Arctic have increased from 2007 through 2011 to 2015 […]

Sep / 22 / 2018

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

Revelations from the dissolved 226Ra-228Ra pair distribution in the South East Pacific Ocean

While it is confirmed that radium-226 (226Ra) is an interesting tracer of the water masses encountered along the GP16 US East Pacific Zonal Transect (EPZT) section cruise, 228Ra data coupled to the dissolved iron (Fe), cobalt (Co) and manganese (Mn) ones provide evidence that lateral transport of sediments from continental margins, including shelves and slopes, […]

Jun / 05 / 2018

Climate change induced spectacular increase of the land-ocean inputs in the Arctic Ocean

Measurements of radium-228 (228Ra) in the framework of the 2015 U.S. GEOTRACES Arctic Transect (GN01), revealed that the surface water content of this tracer has almost doubled over the last decade, specifically in the Transpolar Drift near the North Pole. Radium isotopes are excellent tracers of land-ocean inputs. A mass balance model for 228Ra allowed […]

Jan / 09 / 2018

Coupling Rare Earth Elements concentrations, neodymium and radium isotopes: a powerful tool to decode environmental processes

For the first time, neodymium (Nd) isotopic compositions have been measured together with dissolved and colloidal Rare Earth Elements (REE) concentrations in the Amazon estuary salinity gradient, as part of the GEOTRACES process study AMANDES (Chief scientist: Catherine Jeandel). The sharp drop of REE concentrations in the low-salinity area (already observed in several estuaries) is […]

Jul / 06 / 2015

Two GEOTRACES works question the present ocean chemical elements budgets

New revelations on the land-ocean flux of chemical elements are presented in two different papers highlighting the value of the ocean isotopic data. Both works reveal that the present quantification of the oceanic cycle of the chemical elements need to be revisited…a big question to dig in! When radiogenic and trace metal isotopes suggest that the […]

May / 15 / 2015

Radium quartet reveals no less than four main processes along the GEOTRACES North Atlantic Ocean section (30°N)

The four radium (Ra) isotopes (224Ra, 223Ra, 228Ra, 226Ra, “radium quartet”) are produced in situ via decay of their insoluble  thorium isotope parents in sediments from the continental margins and deep-sea and then released to the ocean. In the ocean, their distributions are controlled by particle removal (226Ra) and radioactive decay with four different half-lives. […]

Jan / 23 / 2015

Nice coupling between radium-228 and neodymium parameter distribution in oceanic surface waters

Using Radium-228 (228Ra) activity as an indicator of coastal water mass influence and a compilation of Neodymium (Nd) parameters in the first 100 m, Chen and co-authors propose that more stratified regions are generally associated with low surface Nd concentrations and that lateral mixing of Nd from coastal surface current is not the only mechanism determining […]

Jul / 14 / 2013

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