Multiplicative Noise in Atmospheric Dynamics: Modeling and Observations 

 

Abstract

The role of multiplicative noise in atmospheric models and meteorological data analysis is discussed. On the one hand the concepts of multiplicative stochastic perturbations and noise-induced transitions are  applied to a quasi-geostrophic ß-plane model of barotropic flow over topography. The stochastic representation of the damping term leads to a multiplicative stochastic forcing. It is found that the qualitative behavior of the system is a function of the multiplicative noise level. It is suggested that the statistics of the unresolved physical processes could be an important factor to understand the behavior of mid-latitude large-scale atmospheric dynamics. On the other hand it is shown that a proper stochastic description of synopticmidlatitude sea surface winds requires a multiplicative noise component. The results indicate that multiplicative noise terms may be necessary in order to fit stochastic models to reality or more complex models.