Fig. 4.

Observations and model simulations of the 10° S transect across the Pacific Ocean. Observations of O₂ (a) and ${\mathrm{NO}}_3^{-}$ (d) are from the World Ocean Atlas 2013 climatology [65], with distance from 175° longitude in the W. Pacific. Arrows in e indicate the idealized 2D flow field, with intensified upwelling driven by wind-stress-induced Ekman transport. Steady state solutions of the metabolic ecosystem model incorporated into the flow field include: O₂ (b), fixed N loss from heterotrophic denitrification and anammox (c), ${\mathrm{NO}}_3^{-}$ (e), and chemoautotrophic C fixation calculated from biomass production rates with a biomass C:N of 5 (f)