Dynamics and predictability of the large-scale atmospheric circulation regimes

We put forward hypothesis that the multiplicity of dynamic regimes in the atmosphere reflects the stationary state - chaos intermittency The quasi-solenoidal model of the nonlinear interaction between planetary atmospheric wave and zonal flow was considered. Numerical simulations demonstrated pronounced intermittent oscillations. Periods of laminar motion are accompanied by blocking of the zonal transfer. A bifurcation mechanism led to appearance of such oscillations was investigated analytically. It was shown that in the generalized space of parameters and phase coordinates the singularity like Whitney set exists which is intersected by the Hopf bifurcation line. The numerical experiments have revealed that the laminar phase is accompanied by the disturbance of exponential scattering of the phase trajectories in spite of the chaotic character of the dynamics on the whole. Local violation of divergence of the trajectories implies a theoretical possibility of forecasting of individual atmospheric formations for time intervals exceeding the mean period of predictability.