  The long-time large-distance behaviour of free decaying two dimensional
turbulence is studied. Stochastic solutions of the Navier-Stokes equation are
explicitly shown to follow renormalisation group trajectories.
  It is proven that solutions of the Navier-Stokes equation asymptotically
converge to fixed points which are conformal field theories. A particular fixed
point is given by the free Gaussian field with a charge at infinity. The stream
function is identified with a vertex operator. It happens that this solution
also admits constant $n$-enstrophy fluxes in the asymptotic regime, therefore
fulfilling all requirements to represent an asymptotic state of two-dimensional
turbulence.
  The renormalisation basin of attraction of this fixed point consists of a
charged Coulomb gas. This Coulomb gas gives an effective description of
turbulence.
