The Economic Effects of Legislation to Reduce Greenhouse-Gas Emissions
"Global climate change poses one of the nation’s most significant long-term policy
challenges. Human activities are producing increasingly large quantities of greenhouse
gases, especially CO2. A strong consensus has developed in the expert community
that, if allowed to continue unabated, the accumulation of greenhouse gases in the
atmosphere will have extensive, highly uncertain, but potentially serious and costly
impacts on regional climates throughout the world. Those impacts are expected to
include widespread changes in the physical environment, changes in biological systems
(including agriculture), and changes in the viability of some economic sectors.
Moreover, the risk of abrupt and even catastrophic changes in climate cannot be ruled
out.1

Those expected and possible harms may motivate policy actions to reduce the extent
of climate change. However, the cost of doing so may be significant because it would
entail substantial reductions in global emissions over the coming decades. U.S. emissions
currently account for roughly 20 percent of global emissions. As a result, substantially
reducing global emissions would probably entail large reductions in U.S.
emissions as well as emissions in other countries. Achieving such reductions would
probably involve transforming the U.S. economy from one that runs on CO2-
emitting fossil fuels to one that increasingly relies on nuclear and renewable fuels,
accomplishing substantial improvements in energy efficiency, or implementing the
large-scale capture and storage of CO2 emissions..."