The Congo River is the world’s second largest river by discharge volume and the only major river discharging into an eastern boundary region. Despite of its size, the Congo River plume and its influence on trace element cycles and ocean primary productivity is poorly constrained. During GEOTRACES cruise GA08, Vieira and co-workers (2020, see reference […]
Jan / 30 / 2020
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
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
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
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
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
Interaction of the currents with the sediments deposited on the margins of the Crozet Islands (Southern Ocean) contributes to the supply of iron and other micronutrients to marine waters. This natural fertilization feeds a phytoplankton bloom that was object of study of the KEOPS 2 GEOTRACES process study. Sanial and co-authors (2014, see reference below) […]
Jul / 23 / 2014