Particulate flux of A1, a component of land origin, in the western North Pacific

Abstract

The particulate fluxes of A1 are generally greater in the western North Pacific than in the central and eastern North Pacific, Atlantic and Antarctic oceans. For instance, sediment trap data reported in this paper show the Al flux in the northern part of the Japan Trench is 12.7 mg m −2 day −1 at 5.2 km depth, 130 times greater than that in the deep Antarctic, even though total particulate fluxes are similar. The particulate fluxes of A1 extrapolated to the ocean surface layer roughly equals the observed A1 flux occurring at the ocean-atmosphere interface, suggesting that particulate A1 is atmospheric in origin. Excess A1 fluxes in the subsurface water probably indicate horizontal transport from the continental margin. This is indicated by the different Mg/K ratios of settling particles between the western and eastern North Pacific.