  In the interstellar medium the turbulence is believed to be forced mostly
through supernova explosions. In a first approximation these flows can be
written as a gradient of a potential being thus devoid of vorticity. There are
several mechanisms that could lead to vorticity generation, like viscosity and
baroclinic terms, rotation, shear and magnetic fields, but it is not clear how
effective they are, neither is it clear whether the vorticity is essential in
determining the turbulent diffusion acting in the ISM. Here we present a study
of the role of rotation, shear and baroclinicity in the generation of vorticity
in the ISM.
