INTEGRATED ASSESSMENT MODELS OF GLOBAL CLIMATE-CHANGE

We review recent work in the integrated assessment modeling of global climate change. This field has grown rapidly since 1990. Integrated as sessment models seek to combine knowledge from multiple disciplines in formal integrated representations; inform policy-making, structure kn owledge, and prioritize key uncertainties; and advance knowledge of br oad system linkages and feedbacks, particularly between socioeconomic and biophysical processes. They may combine simplified representations of the socioeconomic determinants of greenhouse gas emissions, the at mosphere and oceans, impacts on human activities and ecosystems, and p otential policies and responses. We summarize current projects, groupi ng them according to whether they emphasize the dynamics of emissions control and optimal policy-making, uncertainty, or spatial detail. We review the few significant insights that have been claimed from work t o date and identify important challenges for integrated assessment mod eling in its relationships to disciplinary knowledge and to broader as sessment seeking to inform policy-and decision-making.