Abstract
A simple model is used to examine the hypothesis that nonlinear interactions among atmospheric radiation, cumulus convection, and the surface moisture flux can result in a stationary, low-frequency (30–60 day period) oscillating heat source in the tropical atmosphere. The model produces low-frequency oscillations of temperature, moisture, and precipitation. The mechanism that produces these oscillations is identified through analyses of the model and its results. The relevance of this mechanism to understanding the observed Madden-Julian oscillation in the tropical atmosphere over the Indian and western Pacific Ocean is discussed.
