Articles | Volume 17, issue 19
https://doi.org/10.5194/bg-17-4919-2020
https://doi.org/10.5194/bg-17-4919-2020
Research article
 | 
14 Oct 2020
Research article |  | 14 Oct 2020

Effects of 238U variability and physical transport on water column 234Th downward fluxes in the coastal upwelling system off Peru

Ruifang C. Xie, Frédéric A. C. Le Moigne, Insa Rapp, Jan Lüdke, Beat Gasser, Marcus Dengler, Volker Liebetrau, and Eric P. Achterberg

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Cited articles

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Thorium-234 (234Th) is widely used to study carbon fluxes from the surface ocean to depth. But few studies stress the relevance of oceanic advection and diffusion on the downward 234Th fluxes in nearshore environments. Our study in offshore Peru showed strong temporal variations in both the importance of physical processes on 234Th flux estimates and the oceanic residence time of 234Th, whereas salinity-derived seawater 238U activities accounted for up to 40 % errors in 234Th flux estimates.
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