The physical mechanisms of climate change are not yet well understood. This proposal requests support to analyze glacial- interglacial climate change using a series of experiments with a series of energy balance models (EBM). The PI will use a coupled climate-sea ice model (CCSI) to evaluate: 1) the influence of ice transport and leads on polar and global climate and 2) the impact of Milankovitch solar radiation variations on climate. The CCSI will then be coupled with a continental ice sheet model to examine the processes involved in ice sheet initiation and ice sheet response to Milankovitch solar radiation variations. This research program will help to delineate the effects on climate of changes in sea ice distribution and help to isolate the mechanisms of continental ice sheet growth and decay.