The termohaline circulation in the ocean, TallEx: Laboratory Experiments in the formation of Oceanographers and Meteorologists.

DERNIS MEDIAVILLA; L. RUIZ ETCHEVERRY; M. L. C. TEJEDOR; D. MOREIRA; R. FERRARI; C. G. SIMIONATO

Buenos Aires

Congreso; XIII Congreso Latinoamericano e Ibérico de Meteorología (CLIMET XIII) y el X Congreso Argentino de Meteorología (CONGREMET X); 2009

Due the few direct observations in the abyssal flow in the ocean, the laboratory experiments and the theory have been an invaluable guide to deduce the most circulations patterns. Two important inferences can be made from the direct observations collected in the ocean. First, the dense water are formed on the surface in small and highly localized regions of the ocean in the polar seas. Thus, the abyssal circulation appears to be induced for local sources. But, for mass conservation, for each water particle that sinks, another must return to the surface. However, the distributions of the properties not suggest that the return occurs concentrated in one or some few regions of the ocean. Its seems reasonable to assume, then, upwelling occurs in a so dispersed to the basin scale compensating subsidence. On the other hand, the observations also shows that the deep flow is slow and the temporal scales involved are very large. The deep ocean must be, hence, in geostrophic, thermal wind and hydrostatic balance. In these work we discuss the results of laboratory experiments conducted in an acrylic tank mounted on a rotating table in the Departamento de Ciencias de la Atmósfera y los Océanos (DCAO) laboratory, under the Taller de Experimentación en Fluidos Geofísicos (TALLEX). The experiments illustrate the dynamics principles underlying the thermohaline circulation of the oceans, which is forced for the sinking of dense fluid formed in the surface at high latitudes. The sphericity of the Earth is represented by a slopping bottom. The sinking of water in high latitudes is represented by a fluid source in a corner of the tank, using ink as a tracer. It is hoped that these experiments represent a contribution to improving the quality of the teaching of science in our FCEyN and training of human resources in the area of experimental geophysical flows.