Using dye tracers to understand the development of the T–-S structureof the ocean thermocline

Understanding what sets the T--S relation within the thermocline, and
how long and what volume of ventilated waters in each T--S class stay in the sub-surface
thermocline is a key question for climate prediction. In particular the sparsity of
the T--S distribution has been a puzzle since the days of
Stommel. Here we use runs performed for the TICTOC project, in which water is labelled by its
year of ventilation and its source region, to understand how the
volumetric T--S relation is laid down year on year, and  evaluate the
importance of near-surface (mostly vertical) mixing in the first year of ventilation
against longer term mixing (much of which is isopycnal) in specifying the T--S distribution.