An overwhelming majority of climatologists believe there will be significant changes in climate during the next century. Although the rate and magnitude of this change are uncertain, it could happen very rapidly.

In August 1987, a working group of fifty scientists and humanists from Russia, Eastern and Western Europe, the United States, and Canada gathered in Calgary to focus their attention on the impact upon civilization of sudden climate change. One of the more revealing aspects of climate change discussed in Thinking the Unthinkable: Civilization and Rapid Climate Change is that contrary to the popular viewpoint complex societies are more vulnerable to environmental and climate disruption than less “advanced” societies. This work was written to emphasize the gravity of the situation we now face. It should serve to inform not only those concerned with our global environment, but more importantly the policy makers who will be responsible for setting new guidelines and policies aimed at safeguarding our fragile environment.