Science Highlights

Some recent GEOTRACES science findings are reported below.

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 […]

23.01.2015

When direct mapping of diatoms reveals unexpected fate of trace metals in the twilight zone

Twining and co-authors (2014, see reference below) used synchrotron x-ray fluorescence mapping to measure macronutrients such phosphorus (P), sulphur (S), and silicon (Si), and also trace metals like iron (Fe), […]

20.01.2015

Iron isotopes in the Equatorial Pacific Ocean: when the dissolved phases are heavier than the particulate ones

A detailed study of the dissolved and particulate iron (Fe) concentrations and isotopes off the Papua New Guinea coast is proposed. Regarding the sources, iron isotopic composition (δ56Fe) values reveal […]

16.01.2015

Unprecedented set of dissolved manganese data in the North Atlantic Ocean (US GEOTRACES cruise)

Manganese (Mn) is an essential nutrient for biological growth. In the ocean, manganese distribution is sensitive to several processes: redox conditions, photochemistry, biological activity, abiotic scavenging, and also eolian, hydrothermal […]

08.01.2015

What controls the copper isotopic composition in oceanic waters?

Takano and co-workers (2014, see reference below) strongly suggest that the isotopic composition of dissolved copper (δ65Cu) in surface seawater is mainly controlled by supply from rivers, the atmosphere and […]

19.12.2014

Seasonal iron supply in the Southern Ocean is dominated by winter mixing

An international team of researchers analysed the available dissolved iron data taken from all previous studies of the Southern Ocean, together with satellite images taken of the area, to quantify […]

24.11.2014

Why is the deep ocean zinc isotopic signature so heavy?

The oceanic balance of the micronutrient zinc (Zn) is getting more puzzling –although better documented- while the Zn isotope data set increases. Presenting the first high resolution section of seawater […]

14.11.2014

Present day neodymium isotopic composition of the Caribbean Sea deep waters questions the paleo-application of this tracer in restricted basins

The first profiles of neodymium (Nd) concentration and isotopic composition in the Carribbean Sea have been published. They show that surface and intermediate waters flow through the Caribbean with essentially […]

07.11.2014

The sources of the water soluble organic matter contained in the aerosols over the Atlantic ocean decoded

Organic matter is an important component of aerosols, which can absorb (or scatter) light, contributing a warming (or cooling) effect to the atmospheric radiative budget. However, this impact is tightly […]

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