Article 3 of the Kyoto Protocol states a target in which the total amount of emissions of the six greenhouse gases in the developed countries should be reduced by at least 5% compared to that of 1990 during the period of 2008 through 2012, and in Article 4 it is stated that the total amount of emissions of carbon dioxide and other five gases the amount of which is expressed in the equivalent value of carbon dioxide should be reduced so that the emissions does not exceed the following assigned target values.
京都議定書第3条では、2008年から2012年までの期間中に、先進国全体の温室効果ガス6種の合計排出量を1990年に比べて少なくとも5%削減することを目的と定め、続く第4条では、各締約国が二酸化炭素とそれに換算した他5種以下の排出量について、以下の割当量を超えないよう削減することを求めている。