美国克林顿政府1996年4月声称，作为一项有效措施，美国在日本京都召开的联合国防止地球变暖会议（1997年12月1～11日）上所能接受的任何有关减少CO。排放量的建议，都必须包括允许排放额度贸易条款，以使由于减少CO。排放量所增加的成本趋于合理化。美国的“酸雨计划”是世界 The U.S. Clinton administration stated in April 1996 that as an effective measure, the United States should accept any reduction CO concerning the United Nations Earth Summit on Climate Change (December 1-11, 1997) held in Kyoto, Japan. Emissions recommendations must all include the allowances for the trade terms of the credits, so as to reduce the CO. The incremental costs of emissions tend to be rationalized. The U.S. “Acid Rain Program” is the world