Modelling Climate Change and its Economic Consequences

We present a new model for climate system analysis, called CLIMBER-2 (for CLIMate and BiosphERe, level 2). This model fills the current gap between simple, highly parameterized climate models and computationally expensive coupled models of global atmospheric and oceanic circulation. We outline the basic assumptions implicit in CLIMBER-2 and we present examples of climate system analysis including a study of atmosphere-ocean interaction during the last glacial maximum, an analysis of synergism between various components of the climate system during the mid-Holocene around 6000 years ago, and a transient simulation of potential climate change during the next millennium. These studies demonstrate the feasibility of a computationally efficient analysis of climate system dynamics which is a prerequisite for future climate impact research and, more generally, Earth system analysis, i.e. the analysis of feedbacks between our environment and human activities.