Economics focus

摘要

At the beginning of 2001 the Intergovernmental Panel on Climate Change (IPCC) released, as the main result of its massive Third Assessment Review, a set of figures that have become the most-cited numbers in the field of environmental policy, and quite possibly the most-cited numbers in any field of public policy. The panel, whose task was to assess the extent to which emissions of greenhouse gases may warm the planet over the coming century, reported that "globally averaged mean surface temperature is projected to increase by 1.4 to 5.8℃ over the period 1990 to 2100." This alarming conclusion has become the starting-point for popular and official discussion of global warming and the policies that might mitigate it. Bear in mind how expensive some approaches to the problem, such as the Kyoto Protocol, might be if governments actually succeeded in implementing them. Vast sums are at stake.