On Theoretical Limits of Predictability

Abstract

The question of whether long-range deterministic predictions of the atmosphere are possible is examined directly in terms of growth of initial errors. Simple physical models are considered in which a unit mass moves at constant and variable speeds. It is concluded that the distant-future location of the mass is unpredictable in both cases. Estimated growth rates of temperature errors associated with a simple periodic model of the atmosphere are found to be appreciable. To generalize these results, it is suggested that deterministic predictions of meteorological variables are not feasible at long range, if only because of the growth of inevitable initial errors with time.