When ocean dynamic drives the land to ocean input of iron

Nishioka and co-authors demonstrate the pivotal role of tidal mixing in the Kuril Islands chain (KIC) for determining iron (Fe) supply to the euphotic zone of the Western Subartic Pacific. Indeed, Fe derived from sediments in the Sea of Okhotsk is discharged through the KIC into the intermediate water masses (~ 800 m) of the western North Pacific. The redistribution of this Fe-rich intermediate water by intensive mixing as it crosses the KIC is the predominant process determining the ratio of micronutrient (Fe) to macronutrients (e.g., nitrate) in subsurface waters. This process explains the significant phytoplankton growth and great seasonal variability observed in the Western compared to the Eastern Subarctic Pacific.

13 2 Nishioka l

Figure: This image shows the role of tidal mixing in the oceanic dissolved Fe cycle in the subarctic North Pacific, with section profiles of dissolved Fe from this Nishioka’s work and from previous Nishioka’s works (Line P and 165°E line [Nishioka et al., 2001, 2007]).
A basin-scale vertical section profiles for disolved Fe is also shown on the bottom right corner of the figure.Please click here to see the figure larger.



Nishioka, J., T. Nakatsuka, Y.W. Watanabe, I. Yasuda, K. Kuma, H. Ogawa, et al. (2013) Intensive mixing along an island chain controls oceanic biogeochemical cycles Global Biogeochemical Cycles, Volume: 27, Issue: 3 DOI: http://dx.doi.org/10.1002/gbc.20088

Nishioka, J., S. Takeda, C. S. Wong, and W. K. Johnson (2001), Sizefractionated iron concentrations in the northeast Pacific Ocean: Distribution of soluble and small colloidal iron, Mar. Chem., 74, 157–179.

Nishioka, J., et al. (2007), Iron supply to the western subarctic Pacific: Importance of iron export from the Sea of Okhotsk, J. Geophys. Res.,112, C10012, DOI: htttp://dx.doi.org/10.1029/2006JC004055.

Latest highlights

Science Highlights

Tracing dust deposition with aluminium and silicate at a resolution never reached before

Benaltabet and his colleagues propose a study of the dissolved aluminium and silicate fate in the Gulf of Aqaba (Red Sea).


Science Highlights

Actinium-227 distribution traces at least three processes in the North Atlantic Ocean

Le Roy and colleagues report an oceanic section of Actinium-227 in the North Atlantic Ocean.


Science Highlights

Do you want to know more about iron and its isotopes? This review is for you!

Authors present a comprehensive review of iron and iron isotope sources, internal cycling, and sinks in the ocean.


Science Highlights

Different fates of four poorly soluble trace elements in the Pacific Ocean

Zheng and co-authors present the full-depth distributions of aluminum, lead, manganese and copper in the western South Pacific.