Uranium-238 data and physical transports off the Peruvian coast are questioning the thorium-uranium export model
Authors determined insignificant advective and diffusive thorium-234 fluxes at 25 stations in the Peruvian oxygen minimum zone
Pacific Ocean
Surface water trace element and isotope data challenge dust flux models
Using measurements of dissolved and particulate thorium-230 and thorium-232 along a section across the South Pacific, authors estimated the dust flux over this remote area
The power of combining geochemical tracer data with direct current measurements
Learn about new discoveries done combining seawater Rare Earth Elements concentrations and direct physical oceanographic observations
A new model simulates the speciation and dispersion of hydrothermal iron
Roshan and collaborators present new observations of dissolved iron and its physical speciation in the South Pacific
Mechanisms driving biological CO2 drawdown in the Subarctic Pacific unraveled
Nishioka and co-authors compiled comprehensive data sets of iron and macronutrients covering the whole subarctic Pacific…
Loihi Seamount, hydrothermal Helium-3 and dissolved iron sources and their dispersion within the Pacific Ocean
As part of the GEOTRACES cruise GP15, Jenkins and co-workers (2020, see reference below) observed large water column anomalies in helium isotopes and trace metal concentrations above the Loihi Seamount […]
Oceanic Margins as sources of lithogenic particulate and dissolved iron in the North Pacific Ocean
Three GEOTRACES Japanese cruises on board the R/V Hakuho Maru allowed establishing basin-scale and full-depth sectional distributions of total dissolvable iron (tdFe), dissolved iron (dFe), and labile particulate iron (lpFe=tdFe […]
Rare Earth distribution and pattern anomalies in the Solomon Sea
The Solomon Sea is surrounded by high and intensively weathered islands. Its complex topography and hydrography make this area a potential source of trace elements to the waters flowing through […]
South Pacific particulate organic carbon fate challenges Martin’s Law
Joint Science Highlight with US-Ocean Carbon & Biogeochemistry (OCB). Carbon storage in the ocean is sensitive to the depths at which particulate organic carbon (POC) is respired back to CO2 […]
About the decoupled fates of aluminium, manganese, cobalt and lead in the North Pacific Ocean
Did you know that each of these tracers could follow its own marine story, quite decoupled from the others?
All the bioactive elements are not affected by the land-ocean gradient of the atmospheric deposition along the Eastern Pacific Zonal Transect
Atmospheric dust is considered an important source of trace elements to the ocean. As part of the Eastern Pacific Zonal Transect GEOTRACES cruise (EPZT GP16), Buck and co-workers collected 17 […]
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 […]
Cadmium to phosphorus ratio in euphotic zone particulates: why does it vary?
Bourne and co-workers examine the particulate cadmium to phosphorus ratio (Cd/P) variations of 3 particle fractions (<1µm, 1-51µm and >51µm) from 50 casts covering spatial and temporal scales never reached so far […]
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 […]
When hydrothermal iron fertilizes the surface ocean in the Western Tropical South Pacific Ocean
For the first time, iron measurements in the Western Tropical South Pacific reveal that shallow hydrothermal inputs from the Tonga Arc region fertilize the euphotic waters of this vast region. […]
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.
Surface South Pacific ecosystems reflect the availability of the nutrients iron, nitrate and phosphate
Thanks to a high resolution section across the South Pacific (150°E-150°W, GEOTRACES GP13 cruise), Ellwood and co-workers (2018, see reference below) identify that the gradient of sources and fates of […]
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 […]
Dissolved zinc and silicate decoupling in the North Pacific Ocean
Large-scale distributions of dissolved zinc (Zn) in the western and central subarctic North Pacific Ocean was established as part of the North Pacific GEOTRACES section GP02. Kim and co-workers could […]
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 […]
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 […]
Shelf sediment dissolved iron source via non-reductive dissolution in the Gulf of Alaska
Crusius and co-workers (2017, see reference below), reveal temporal and spatial variability in the sources of iron (Fe) to the northern Gulf of Alaska, based on data from cruises from […]
Important external dissolved iron inputs, HNLC water formation and strong biological seasonality explained in the North Pacific Ocean
Subarctic Pacific is known as High Nutrient, Low Chlorophyll (HNLC) area, where phytoplankton growth is limited by dissolved iron (DFe) availability. The biological activity in the surface waters is also […]
What controls hydrothermal plume transport of iron over 4000 km in the deep Pacific Ocean?
The striking extension of the dissolved iron and manganese plumes over more than 4000 km from their hydrothermal sources along the US GEOTRACES East Pacific Zonal Transect (EPZT) cruise (GP16) has […]
Siderophores facilitate microbial adaptation to iron limitation in the eastern tropical Pacific Ocean
Siderophores are organic compounds secreted by microbes to facilitate iron uptake. Using new methods to characterize trace metal organic ligands in seawater, Boiteau and colleagues (2016, see reference below) measured […]
Up to four mercury species measured along the GEOTRACES East Pacific Zonal Transect
Total mercury (HgT), elemental mercury (Hg0), monomethyl-mercury (MMHg), and dimethyl-mercury (DMHg) were measured at an unprecedent resolution so far along the East Pacific Zonal Transect (EPZT) GEOTRACES cruise (GP16). Knowing […]
Oxygen biogeochemistry exerts a strong influence on cobalt cycling
This is an important result of the US GEOTRACES East Pacific Zonal Transect (EPZT) cruise (GP16) discussed by Hawco and his co-workers (2016, see reference below). The distribution of dissolved […]
Prokaryotic communities display elevated trace metal concentrations in Pacific oxygen deficient zone
Local particulate maxima in many bioactive trace metals (cadmium, Cd; cobalt, Co; nickel, Ni; vanadium, V; and zinc, Zn) are found in the upper Oxygen Deficient Zone (ODZ), coincident with […]
Lithogenic influence from the Hawaiian Islands detectable up to Station ALOHA surface waters
By coupling neodymium (Nd) and radium (Ra) isotopes and Rare Earth Element (REE) signals, Henning Fröllje and co-workers (2016, see reference below) show that the coastal Hawaiian waters are affected […]