Descriptive, prescriptive and second-best approaches to the control of global greenhouse gas emissions

A prescriptive, second-best approach is developed for determining the control of greenhouse gas emissions in an inter-temporal multi-region model of the world. Concerns about inter and intra-generational equity are reflected in the rate of time preference and regional weights of a social welfare function. Choices are narrowed down by the ethical principle of anonymity. A third dimension of equity, inequality aversion, is subject to greater variation. The aggressiveness of recommended abatement can be made to bracket results for a common descriptive model by the choice of inequality aversion. In this manner, the perception of a sharp dichotomy between descriptive and prescriptive approaches is moderated.