An important part of global change studies is to understand how the Earth's climate has varied naturally in the past.  Knowledge of historically observed variations in climate provides us with information on current climate conditions and recent climate changes.  Studies of the geologic record extend our knowledge of the Earth's climate far beyond historical records by providing  evidence of climates drastically different from today.  By studying these ancient climates, and climate changes, we can understand the inner workings of the climate system.  By coupling the knowledge of the climate system with knowledge of historical climate conditions, we can predict future climate change. 

In order to understand fully the workings of the climate system, we must study climate change in all regions of the globe.  The Arctic and Subarctic are thought to have particularly sensitive climates.  These regions are expected to respond early and with great strength to global-scale changes in the Earth's climate system (e.g. the human-induced greenhouse effect).  The significance of this response increases when we consider the potential effects of rapid arctic and subarctic climate change on the climate of the entire planet.  Examples of such changes (called feedbacks) are altered ocean circulation due to melting of arctic sea ice, and the release of large amounts of greenhouse gasses by melting of arctic permafrost layers and warming of arctic tundra soils.