中文摘要：

以北京、天津、上海为例,探讨了城市碳排放趋势预测的研究方法。采用最优增长率模型,研究了经济平稳增长的条件下,各市未来的能源碳排放趋势。考虑了水泥工业的碳排放量,并采用CO2FIX模型计算各市森林碳汇量,从而得到各市净碳排放量。结果表明：北京、天津、上海的能源碳排放量都呈倒U型曲线,上海的碳排放量远高于北京和天津两市。北京、天津、上海的水泥碳排放量都呈增加趋势,其中北京每年的水泥碳排放量最大,且增长率也是3个城市中最大的。北京和天津的累计森林碳汇量不断上升,上海的累计森林碳汇量几乎为零。北京、上海、天津的净碳排放量仍呈倒U型曲线增长,但与不考虑水泥碳排放和森林碳汇时的情况差别不大。由此可见,北京、上海、天津应重点减少能源碳排放,有效控制水泥产业碳排放,逐步扩大植树造林面积,从多方面采取措施降低碳排放。

英文摘要：

Taking Beijing,Tianjin and Shanghai for examples,the predictable method was discussed for the carbon emission.Under the conditions of steady economic growth,the trends of their carbon emission from the energy sources were discussed with the model of optimal growth rate.The net carbon emission of each city was gotten after taking into account the carbon emission from the cement industry,and calculating forest carbon sink of each city with the CO2 FIX model.The results showed that in Beijing,Tianjin and Shanghai,the carbon emission from energy sources presented an inverted U-shaped curve,and the carbon emission of energy sources in Shanghai was much higher than that of Beijing and Tianjin.The carbon emission of cement in Beijing,Tianjin and Shanghai,experienced an increasing trend,the annual carbon emission of cement in Beijing was the biggest,and the growth rate was also the biggest among the three cities.In Beijing and Tianjin,the cumulative forest carbon sink is rising,and the accumulated forest carbon sink in Shanghai was almost zero.Net carbon emissions were still growing as the inverted U-shaped curve in Beijing,Shanghai and Tianjin,but the situation was not very different when not taking into account of the cement carbon emission and forest carbon sink.Thus,in Beijing,Shanghai and Tianjin,the effective measures to reduce carbon emission should mainly reduce energy consumption carbon emission,control the carbon emission from the cement industry effectively,and gradually expand the area of afforestation.