This award supports studies of long-term (Pleistocene and Cenozoic) climate change aimed at developing a plausible physical model to account for the simultaneous time-evolution of many climatic variables (e.g., ice mass, CO2, ocean state and surface temperature and their spatial distributions). The studies involve statistical analyses of the relevant time-series records as well as theoretical studies based on both "deductive" physics (using general circulation models and statistical-dynamical models) and "inductive" low-order models (using qualitative physics, structured by the theory of dynamical systems analysis). This work will enlarge upon our present theory of Pliocene/Pleistocene climatic evolution by (a) extension to Pre-Pliocene changes, (b) extension to a two-dimensional geography, (c) incorporation of explicit ocean dynamics, (d) explicit treatment of the continental biosphere, and (e) establishing closure relations between the fast and slow response variables by systematic GCM studies.
