Circulation

Particulate fluxes and circulation in a changing Arctic Ocean: tracer data and modeling

A complete review of published and new water column profiles of thorium-230 (230Th) and protactinium-231 (231Pa) concentrations and neodymium (Nd) isotopic compositions collected in the Amerasian Basin of the Arctic Ocean between 1983 and 2015 was performed by Grenier and co-workers (2019, see reference below). This review allowed them to identify regional and temporal variability […]

Mar / 27 / 2020

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 comparable to losses from atmospheric thermodynamic forcing. Beyond the Arctic Ocean, the water mass transport and transformation processes in the North Atlantic Ocean substantially contribute […]

Jan / 30 / 2019

Astonishing protactinium and thorium profiles in the Mediterranean Sea

In the framework of the GEOTRACES cruise along the GA04 section in the Meditterranean Sea, Gdaniec et al. (2018, see reference below) measured thorium (Th) and protactinium (Pa) isotope distributions on 8 profiles across the Mediterranean Sea. Contrasting with what is observed in the open ocean: Depth profiles of these tracers are non linear, indicating […]

Mar / 29 / 2018

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 Busan (South Korea) to Suva (Fiji) (Figure a). This beautiful set of Nd concentration ([Nd]) and isotopic (εNd) signature data allow Behrens and co-workers (2017, […]

Dec / 06 / 2017

What do the first 236-Uranium data reveal in the Arctic Ocean?

Casacuberta and co-authors (2016, see reference below) propose the first set of data for the artificial radionuclide 236-Uranium (236U) in the Arctic Ocean. The novelty of this study compared to the first comprehensive dataset they published in the western North Atlantic Ocean (GEOTRACES GA02 section), is the combination of 236U with 129-Iodine (129I). The 236U/238U and […]

Mar / 10 / 2016

Lead isotopes tracks leakage of Indian Ocean seawater into the Atlantic Ocean

Stable lead isotopes have been measured by Maxence Paul and co-workers along 40°S during the first and second legs of the UK GEOTRACES cruise (GA10) in the Atlantic Ocean. They clearly help to identify three different end-members and mixing between them: open ocean South Atlantic seawater, Indian Ocean seawater, and coastal inputs from South Africa. […]

Jan / 15 / 2016

Dissolved gallium in the Beaufort Sea: a promising conservative water mass tracer

Mc Allister and Orians (2015, see reference below) present the first dissolved Ga (DGa) data ever reported in the Arctic. DGa behaves very conservatively, helping to constrain the mixing of water masses of Pacific and Atlantic origins. Its conservative behaviour helps distinguishing seasonal processes that are influencing temperature and Nitrate:Phosphate of Pacific Water entering the […]

Aug / 24 / 2015

Neodymium isotopic signature of the Ross Sea Water characterized

The first seawater neodymium isotopic compositions (εNd) and neodymium concentrations [Nd] profiles across the South Pacific circum-Antarctic fronts have been published recently (Basak et al., 2015, see reference below). Thanks to this exceptional GEOTRACES-compliant data, collected on R/V Polarstern cruise PS75, authors characterize the εNd signature of Ross Sea Bottom Water (εNd ~ -7) and show that […]

Jun / 12 / 2015

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