Helium isotopes help to constrain high-resolution model dynamics in the Mediterranean Sea

The terrigenic helium isotope distribution was simulated for the first time in the whole Mediterranean Sea, using a high-resolution model (NEMO-MED12) at one-twelfth of a degree horizontal resolution (6–8 km).

Together with providing valuable constraints on the crustal and mantle helium fluxes, the simulations and their comparisons with observations provide a new technique for improving the dynamical regional model. This is clearly illustrated by the confirmation of the shortcomings of the model dynamics in representing the deep ventilation of the Ionian sub-basin…

16 Ayache
Figure: Total δ 3He (sum of terrigenic, tritiugenic and atmospheric helium) model–data comparison along the Meteor M5 (September 1987) section. (a) Colour-filled contours indicate simulated δ 3He (%), whereas colour-filled dots represent in situ observations. (b) and (c): comparison of average vertical profiles for the Levantine and Ionian sub-basins, respectively; model results are in blue; red indicates in situ data. Click here to view the figure larger.


Ayache, M., Dutay, J.-C., Jean-Baptiste, P., & Fourré, E. (2015). Simulation of the mantle and crustal helium isotope signature in the Mediterranean Sea using a high-resolution regional circulation model. /Ocean Science/, /11/(6), 965–978. doi:10.5194/os-11-965-2015

Latest highlights

Science Highlights

A new proxy for ocean iron bioavailability

The approach established and verified in this study, opens a new way for determining dissolved iron bioavailability in samples across the ocean.


Science Highlights

Scavenging differentiates the distribution of cadmium, nickel, zinc and copper in the North Pacific Ocean

Zheng and co-authors observed sectional distributions of cadmium, nickel, zinc, and copper in the North Pacific Ocean during three GEOTRACES related cruises…


Science Highlights

Surprising conservativity of trace metals along a costal embayment salinity gradient

Chen and co-workers analyzed an array of trace metals together with Rare Earth Elements in a salinity gradient in the Jinhae Bay, the largest semi-enclosed bay in South Korea…


Science Highlights

Measuring actinium-227 by mass spectrometry is feasible, sensitive and reliable!

Levier and co-authors have developed a new protocol measurement of the dissolved actinium in seawater.