The high total carbonate in the northwestern region suggests high biological productivity. The settling products are decomposed immediately below the summer mixed layer and increase the total carbonate in the subsurface. In the eastern Pacific, alkalinity becomes lower, suggesting high alkalinity pump effects, which reduce alkalinity in the model subsurface (a couple of hundreds meters depth).
The further misfit possibly occurs: e.g., horizontal advection of water and biological production in winter are completely omitted in the model. However, the good representation of the physical properties suggests appropriateness of the present one-dimensional model for reproducing the fundamental signatures. The biological production could be significant in the subtropical region even in winter, although it is of interest that the chemical properties are well reproduced in the forward calculations.
ACKNOWLEDGEMENT
The present work was partially supported by Japan Marine Science and Technology Center, Japan Marine Science Foundation and National Space Development Agency.
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