Abstract
In this report, the potential for salt finger instability in the central water of the World Ocean is examined. The form of the temperature– salinity relationship determined from the Levitus climatological data and the density ratio of this relationship are used as a proxy to identify the regions that are susceptible to salt finger activity. The analysis indicates that most of the North and South Atlantic basins, and southeastern Indian and southwestern South Pacific Central Waters have density ratios smaller than 2.0. This is an indication that enhanced vertical salinity fluxes due to salt fingers can be an additional process affecting the thermocline freshwater budget. This study also indicates that most of the ocean's central water T–S curves are better described by a constant density ratio T–S curve than by a straight line connecting near-surface and intermediate water types.