  We demonstrate that relativistic conformal hydrodynamics in 2+1 dimensions
displays a turbulent behaviour which cascades energy to longer wavelengths on
both flat and spherical manifolds. Our motivation for this study is to
understand the implications for gravitational solutions through the AdS/CFT
correspondence. The observed behaviour implies gravitational perturbations of
the corresponding black brane/black hole spacetimes (for sufficiently large
scales/temperatures) will display a similar cascade towards longer wavelengths.
