A Model of the Internal Feedback System Involved in Late Quaternary Climatic Variations

Abstract

Because of the small net rates of energy flow involved in very long-term changes in ice mass (10?1 W m?2) it will be impossible to proceed in a purely deductive manner to develop a theory for these changes. An inductive approach will be necessary-perhaps beg formulated in terms of multi-component stochastic-dynamical systems of equations governing the variables and feedbacks thought to be relevant from qualitative physical reasoning (e.g., ?conceptual models?). The output of such models should be required to conform as closely as possible to all lines of observational evidence on climatic change, have a predictive quality in the search for new observational evidence, and satisfy the general conservation laws and all the results of physical measurement of the fast response (high energy flux) processes that generally lead to diagnostic relationships. A prototype of such an inductive model is described. This model is formulated as a nonlinear dynamical system governing three components: continental ice mass marine ice mass, and bulk ocean temperature. The solution is shown to have several properties in common with geological evidence for the variations of these quantities.