Abstract
A state variable 
(
,s) most sensitive to isopycnal thermohaline variations and least
correlated with the density field is proposed.
is constructed so that its diapycnal gradient d
is related to the density gradient ratio R
:d
(1+R
)/(1-R
). It is simultaneously a tracer conserved by isentropic motions, and
an indicator of diffusive stability. It is useful for the combined description
of interleaving and double-diffusive processes at the boundary between water
masses.
Author Keywords: Equation of state; Double diffusion;
Tracer
