FROM SHORT-SCALE ATMOSPHERIC VARIABILITY TO GLOBAL CLIMATE DYNAMICS -TOWARD A SYSTEMATIC THEORY OF AVERAGING

Traditionally, climate is defined by the properties of the averages of the meteorological fields over an appropriate time interval. In this paper die properties of the time-averaged observables of a red noise a tmosphere and of a simplified model of thermal convection are investig ated both analytically and numerically and are compared to those of th e original finescale variables. It is shown that averaging tends to re duce the domain of variability and the attractor dimension favors pers istence of initial correlations and enhances predictability. The impli cations of these findings in the real-world atmosphere are briefly ass essed.