Title: Dynamic Transitions for thermohaline circulation

Abstract: Oceanic circulation is one of key sources of internal
climate variability.  One important source of such variability is the
thermohaline circulation (THC). Physically speaking, the buoyancy
fluxes at the ocean surface give rise to  gradients in temperature and
salinity, which produce, in 
turn, density gradients. These gradients are, overall, sharper in the
vertical than in the horizontal and are associated  therefore with an
overturning or THC. 

In this talk, I shall present a new  mathematical theory associated
with the thermohaline circulations (THC). The results derived provides
a general transition and stability theory for the Boussinesq system,
governing the motion and states of the large-scale ocean
circulation. A convection scale law is introduced, leading to an
introduction of proper friction terms in the model in order to derive
the correct circulation length scale. In particular, the dynamic
transitions of the model with the derived friction terms suggest that
the THC favors the continuous transitions to stable multiple equilibria.