An approach to modeling climate based on feedback relationships

Feedback occurs between many components of the climate system, and makes the study of climate very difficult. A modeling approach is presented in which feedbacks are represented specifically. Analysis of very simple models shows how feedback between two components affects their behavior; positive feedback increases persistence, and can produce climatic changes even without changes in external forcing. In any quantitative study, the magnitudes of all relevant feedbacks must be known accurately. As an example, it is shown how the effect of CO₂ on global temperature must depend greatly on the feedback between global temperature and ice extent.