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A previously formulated dynamical model of the late Pleistocene ice ages (based on the hypothesis that the global CO2 system can provide the instability to drive a natural oscillation involving feedbacks between the cryosphere, atmosphere, and ocean) is extended to include (1) additive earth orbital forcing (summer insolation changes at 65°N) and (2) tectonic forcing in the form of a postulated variation in the multiplicative parameters (rate constants) of the model system. The structural (e.g., bifurcation) properties of the model are examined in detail to reveal the regions of parameter space wherein the geologically inferred features of the full Pleistocene can be simulated, including the observed chronology, the phase relationships between ice, CO2, and North Atlantic Deep Water formation, and the mid‐Pleistocene transition.

Observational studies of the atmospheric energy cycle involving large‐scale components of the general circulation, as measured by wave number around latitude circles, are reviewed. The relevant equations are set down in full form for a closed global system. All pertinent observational studies of the terms arising in these equations are listed chronologically, and the results of the most comprehensive of these studies are displayed in energy flow diagrams for winter and summer average conditions. The need for further work is suggested by the imbalances and omissions and the inadequacies of data coverage.

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A dynamical model of the Pleistocene ice ages, incorporating many of the qualitative ideas advanced recently regarding the possible role of ocean circulation, chemistry, temperature, and productivity in regulating long‐term atmospheric carbon dioxide variations, has been constructed. This model involves one additional term (and free parameter) beyond that included in a previous model (B. Saltzman and A. Sutera, 1987), providing the capacity for an asymmetic (for example, “saw‐toothed”) response. It is shown that many of the main features exhibited by the δ18O‐derived ice record and the Vostok core/δ13C‐derived carbon dioxide record in the late Pleistocene can be deduced as a free oscillatory solution of the model, including a rapid déglaciation during which a spike of high CO2 and a rapid surge in North Atlantic deep water production occurs. It is expected that the addition of reasonable levels of external (for example, Earth orbital) forcing will enable the model to account for a significant amount of the remaining observed variance and covariance of the slow response climatic variables over the full Pleistocene including the mid‐Pleistocene transition.