Oxygen 18–salinity relationship simulated by an oceanic general circulation model

Abstract

The distribution of H 2 18O in the ocean is simulated using an oceanic general circulation model (GCM). Surface isotopic fluxes prescribed to this model are derived from an atmospheric GCM, which ensures their consistency. The oceanic GCM is initialized with a homogeneous composition, and redistributes isotopic gradients so as to equilibrate with the atmosphere. A good agreement is found between the observations and the simulation concerning (i) the interbasin H 2 18O gradients, especially the Atlantic being more enriched than the Pacific, as well as the meridional gradients; and (ii) the H 2 18O–salinity relationship.