The climate of the earth during Marine Oxygen Isotope stage 3 was dominated by a millenium timescale oscillation between cold stadial and warm interstadial conditions first discovered by Willi dansgaard nd Hans Oescger on the basis of analysis of oxygen isotopic data from the GRIP ice core drilled at Summit Greenland. recently published analyses by Peltier and Vettoretti (2014) have demonstrated that this oscillatory process has be recovered in long integrations of the University of Toronto version of the NCAR CCSM4 coupled climate model. The exlanation has recently been found for the discrepency between the observed period of this oscillation and that originally predicted by the model. In this talk I will address the issue of the relationship between the warm and cold states of this oscillation and the quasi-steady cold climate characteristic of Last Glacial Maximum conditions which developed during MIS 2. I will also show that this state is extremely sensitive, especially in terms of the strength of the overturning circulation, to vegetation feedbacks when the model is coupled to a dynamic vegetation model.