Zinc and lead isotopes reveal human footprint on the most remote oceanic regions
Benaltabet and co-workers analysed suspended particles collected on GEOTRACES GP21 cruise tracked from Chile to New Caledonia.
Isotopes
Contraction of North Atlantic Deep Water during glacial times: a paradigm called into question
Blaser and co-authors propose a new distribution of deep-water masses in the Atlantic Ocean during the Last Glacial Maximum and the Heinrich Stadial 1…
Magmatic activity at the Carlsberg Ridge in the Indian Ocean triggered by glacial sea-level variation
De and colleagues provide a high-resolution record of magmatic input and associated hydrothermal activity over the past 49 kyr from a core recovered from a magmatic segment of the slow-spreading Carlsberg Ridge in the Indian Ocean.
Mercury content and isotopes in bird’s guano: a window to reconstruct past climates
By analysing peat cores, Chuxian Li and her colleagues have shown how populations of nesting seabirds have fluctuated on a sub-Antarctic Island over the last 8,000 years.
Sedimentary controls on seawater nickel distributions and nickel isotope compositions: a two steps study
Nickel isotopic mass balance in the ocean stands among the less understood so far…
Lead isotopes, reversible scavenging and ventilation processes in the South Atlantic Ocean
Olivelli and co-authors present seawater lead concentrations and lead isotopes for 10 depth profiles collected in the South Atlantic Ocean.
Pulling back the veil on reversible scavenging of lead
This work further contains the role that reversible scavenging may play in the cycling of lead in the ocean, an ever-evolving global experiment where lead contamination can be tracked in real-time.
The North Pacific Ocean, a key actor for the zinc oceanic cycle
Sieber and his colleagues lift the veil on some of the mechanisms that control the behavior of zinc in the Pacific Ocean, and more globally.
Disentangling what controls the cadmium distribution in the Pacific Ocean
Sieber and his colleagues established the distribution of dissolved cadmium concentrations and isotopes in a section extending from Alaska to Tahiti.
Nickel bioactive role in the oceans assessed by its isotopes
Lemaitre and her colleagues realized the simultaneous analysis of the dissolved nickel isotopes and concentrations in the North Atlantic.
Mercury stable isotopes constrain atmospheric pathways to the ocean
The study’s results hold promise that the implementation of anti-pollution measures under the Minamata Convention will likely result in a faster decrease of oceanic mercury levels than previously thought.
Isotopic chromium variations do not always reflect the occurrence of low oxygenated waters
Dissolved chromium (Cr) in the ocean is present under two oxidation states: The oxidized and soluble Cr (VI) and the reduced more reactive Cr (III). Reduction of Cr (VI) to […]
Using the three thorium isotope toolbox to probe the particle dynamic within an East Pacific Rise hydrothermal plume
The insoluble radiogenic isotopes of thorium (Th) are produced at a known rate in the water column via the decay of soluble uranium (234Th, 230Th) and radium (228Th) isotopes. These […]
The circulation loop in the North Atlantic and Arctic oceans depicted by the artificial radionuclides
Three articles from three cruises highlighted here! Atlantic waters have been recently recognized to play an increasing role in reducing sea-ice extent in the Arctic Ocean at a rate now […]
Cadmium isotopes, tracers of the cadmium sequestration as cadmium sulphide in oxygen minimum zone?
The linear relationship between the seawater cadmium and phosphate dissolved concentrations lead to use the cadmium/calcium (Cd/Ca) imprinted in calcareous archives to reconstruct the past phosphate (PO4) distributions. However, variations […]
Local geologies imprint the Antarctic Bottom Water neodymium isotopic signatures
Dissolved neodymium (Nd) isotopes and concentrations were measured at six stations in the Australian sector of the Southern Ocean, targeting the study of the Adelie Land Bottom Water (ALBW), a […]
More realistic oceanic particle field improved the thorium-230 and protactinium-231 modeling
Thorium-230 (230Th) and protactinium-231 (231Pa) are two geochemical tracers extensively used for investigating particle transport in the ocean and reconstructing past ocean circulation. A key feature in reproducing their distributions by […]
Helium-3 plumes in the deep Indian Ocean confirm hydrothermal activity
Thanks to samples collected as part of the Japanese GEOTRACES cruise in 2009 – 2010, along section GI04, Takahata and co-workers (2018, see reference below) identified a maximum helium-3 ratios […]
The role of melting-ice in driving the slowdown of circulation in the western Atlantic Ocean revealed by protactinium-thorium ratio
Abrupt climate changes in the past have been attributed to variations in Atlantic Meridional Overturning Circulation (AMOC) strength. Knowing the exact timing and magnitude of the AMOC shift is important […]
Environmental changes in the Arctic Ocean are occurring now!
Radium-228 increase in the central Arctic (2007 to 2015), is attributed to stronger wave action on shelves due to a longer ice-free season.
Influence of particle composition on the rate constants of thorium adsorption
Chemical species are constantly exchanged between seawater (solution, D) and particles (solid material, P). This continuous D-P exchange is a key process determining the chemical composition of the ocean. Particles […]
Contrasting fates of the cadmium-cadmium isotopes in the Kuroshio and Oyashio environmental systems
Yang et al. (2018, see reference below) studied the relative importance of physical and biogeochemical processes on controlling the isotopic composition of dissolved and particulate cadmium (Cd) in a GP18 […]
Labile particulate iron isotopic signatures trace hydrothermal and margin inputs down to the benthic layers in the Eastern Pacific Ocean
For the first time, labile and total particulate iron (pFe) isotopic signatures were measured along a full depth oceanographic section (more than 200 0.8-51 µm-sized particles) in the Eastern Pacific […]
Revelations from the dissolved 226Ra-228Ra pair distribution in the South East Pacific Ocean
They show that radium-228 data coupled to the dissolved iron, cobalt and manganese provide evidence that lateral transport of sediments from continental margins.
Why did the concentration of atmospheric carbon dioxide rise so much and so quickly during the last deglaciation?
During the Last Glacial Maximum, the deep southern Pacific waters were stratified, efficiently accumulating old, CO2 rich waters. Basak and co-authors (2018, see reference below) measured neodymium isotopes in sediment […]
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 […]
New neodymium concentration and isotopic data from the West Pacific Ocean
In the framework of the GEOTRACES TransGeoBioOc process study (GPpr04), seawater samples were collected at 12 stations (and up to 17 depths per stations) along the SO223T cruise transect from […]
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 […]
Short-Term Variability of Dissolved Rare Earth Elements and Neodymium Isotopes in the Entire Water Column of the Panama Basin
Patricia Grasse and co-workers (2017, see reference below) present new dissolved neodymium isotope compositions (εNd) and rare earth element (REE) concentrations from the Panama Basin. REE concentrations peak at the […]
Surprising cadmium isotope results north of the Subantarctic Front in the South West Atlantic Ocean
Xie and co-workers (2017, see reference below) report cadmium (Cd) isotopic compositions from five stations and 15 tow-Fish surface waters from 50ºS to the equator along GEOTRACES GA02 Leg 3. […]