Necessity of reducing greenhouse gases CO2 has a life of 50 to 200 years. The UN estimates that in 1992 the amount of CO2 in the atmosphere had increased 30 % since the industrial revolution. If in the 21st century we want to keep to a level of twice that of the industrial revolution, then the world's CO2 emissions will have to be reduced by more than half.
★溫室氣體減量的必要 CO2 壽命長達 50-200 年，聯合國估計，1992 年時，全球 CO2 已比工業革命時增加 30 %，若要在 21 世紀末將濃度保持在工業革命時的 2 倍，則全球 CO2 之排放量需較目前削減一半以上。