么空气如此重要答出3条即可____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________2大气中多余的二氧化碳从何而来从上述材料可以看出人类赖以生存的大气正遭受空前严重的破坏二氧化碳作为一种主要的温室性气体含量增加导致气候变暖地球