Numerical experiments on the genesis of Sharav cyclones: idealized simulations

A three-level channel flow model is used to investigate the generation of Sharav cyclones in the lee of the Atlas mountains through "idealized' numerical experimentation. A typical initial state consists of a barotropic high-low system, embedded in baroclinic shear flow and centered to the north of the Atlas Mountains. The upper-level trough intensifies slightly when crossing the mountain range and induces then a low-level cyclone in the lee. The trough turns eastward later on and the new cyclone stays close to this upper-level centre. A simple two-dimensional three-layer model is used to explain salient features of this type of lee cyclogenesis. Moreover, additional experiments are conducted in order to elucidate details of the cyclogenetic process. -from Authors