emission limit

• Yet one of the main sticking points for the u . s . ? the absence from that accord of a requirement that developing countries agree to firm emission limits ? looms as even more of an obstacle as a successor agreement is contemplated to take effect when kyoto expires in 2012
  在规范开发中国家同意固定排放量的协议中，美国缺席了，但这个胶著的问题将随著2012年京都议定书到期、世界各国斟酌是否拟定后续协议，而显得越来越棘手。