Descriptive or conceptual models? Contributions of economics to the climate policy debate

Economists have brought two distinct modeling styles to the debate on climate policy. Some attempt to forecast the effects of policy decisions by constructing models that purport to be "descriptive" of the global economic system. The alternative approach is a "conceptual" focus on key elements of a particular economic or environmental issue. The descriptive models typically offer numerical comparisons of policy scenarios to a baseline, while the conceptual modelers often seek to provide insight into the ethical foundations or implications of different assumptions. These different modeling styles exhibit both contrasts and areas of overlap in their policy implications. © Springer 2005.