Interplay between chaos and external noise in an extended system: improved forecasting due to intrinsic stocahstic resonance phenomena

Abstract

We have investigated the effects of noise on an extended chaotic system using as benchmark the Lorenz'96 model. The analysis of the system's time evolution and its time and space correlations show numerical evidence for two distinct stochastic resonance-like behaviors as a function of the external noise intensity, or the system size, and they result to be only weakly sensitive to an external periodic signal. The underlying mechanisms can be associated to a noise induced chaos reduction. A new view of the stochastic resonance phenomenon in a nonstationary situation is shown, studying the resonant phenomena implications in forecasting by exploiting a new method that quantifies the reduction of chaos error evolution process.