LOCALIZED CONVECTION IN ROTATING STRATIFIED FLUID

We study the convective overturning of a rotating stratified fluid in the laboratory. Convection is induced from the surface of a salt-strat ified fluid by the introduction of salty fluid over a circular area. T he external parameters are buoyancy forcing of strength, B-0, applied over a circular area of radius R(s), the rotation rate as measured by f, ambient stratification N, and the depth H. The experiments are moti vated by physical scaling arguments which attempt to predict the lengt h and velocity scales of the convective chimney as it adjusts under gr avity and rotation and breaks up through baroclinic instability. The s cales of interest include the number, size, and typical speeds of the fragments of the broken chimney, the final depth of penetration of the convective mixed layer, and the total volume of convectively produced water. These scales are tested against the laboratory experiments and found to be appropriate. In this idealized problem we have found the depth of penetration depends only on the size and strength of the forc ing and the ambient stratification encountered by the convection event ; it does not depend explicitly on rotation. The implications of the w ork to deep water formation in the Labrador Sea and elsewhere are disc ussed. Finally, the study has relevance to the role and representation of baroclinic eddies in large-scale circulation of the ocean.