Earth System Modeling—An Integrated Assessment Tool for Environmental Studies

This paper overviews a wide spectrum of influences on the Earth’s climate system. These include external effects, such as variations in the solar energy output, and internal influences. Internal influences include both natural and human-caused effects. The feedbacks associated with the Earth’s climate system are nonlinear and occur over a range of time and space scales. As a result, our ability to predict the future of climate is hindered, and perhaps impossible. We need to assess integrated Earth system climate models to assess the limits of predictability, to evaluate when sudden transitions might occur, and to evaluate the vulnerability of the climate to human-caused and natural forcings. These subjects are discussed in this paper.