Fractal Attractor of the Deep Convection Cycle in the Northwest Mediterranean Sea

Abstract. Deep convection in the Gulf of Lion is an important ocean mixing process in the western Mediterranean Sea caused by large cooling fluxes at the sea surface. It aids the Mediterranean thermohaline circulation, and promotes phytoplankton blooming. This work investigates the three different periods of the process: preconditioning, deep convecting, and restratification, through the lens of fractal attractor analysis with the local correlation dimension. From the analysis it was determined that preconditioning period is most predictable period, with a local correlation dimension of 10 to 30, followed by the deep convecting period, with a local correlation dimension of 30 to 45. However, the deep convecting period can also exhibit random process like behavior with local correlation dimensions growing exceedingly high in April and May. The least predictable period was the restratification period, with typical local correlation dimensions of 50 to 80 near the end of restratification.