The Algerian current: comparisons between in situ and laboratory data sets

The Algerian current is compared to a laboratory current created in a rotating tank. The experimental current flows along a regular wall and over a motionless denser water, with a constant flow rate and a uniform velocity at the source. Data collected in the laboratory are compared with satellite and in situ data sets. The various characteristic phenomena are shown to be similar: both currents are unstable and generate meanders and cyclonic–anticyclonic eddy-pairs. Eventually, the anticyclone remains and is associated with a marked lowering of the interface. The phase speed and growth of the meanders and the shape and size of the eddies in the laboratory are in quite good agreement with those deduced from in situ data and satellite images. The observations and the velocity and interface height measurements in the laboratory allow a better understanding of the Algerian current dynamics and its instability process.