Study On Dynamic Changes And Influence Tactors Of Direct And Embodied Carbon Emission In City Scale

Cities have played a more and more important role in global warming in recent years, so research on carbon emission in city has become a hotspot. This paper takes Shanghai as an example to make a comprehensive analysis of direct carbon emission and embodied carbon emission in urban trade activity. By confirming the main influence factors in the changes of carbon emission, such efforts can open up avenues for better constructions of low carbon economy for Shanghai.. After accounting for the direct carbon emission based on the energy consumption activity in industries, embodied carbon emission is calculated with Input-Output Table. In addition, this paper conducts time series analysis for the influence coefficient and sensitivity coefficient of carbon emission in economic industries. Structural decomposition analysis is adopted to analyze the influence of CO2 emission intensity, intermediate production structure, final demand structure, per capita final demand volume, and population on the total direct carbon emission change by stage and by sector. In consideration of the increasing volume of import and export in Shanghai, structural decomposition analysis is also used to analyze the influence of CO2 emission intensity, intermediate production structure, import/export structure, import/export volume on the changes of embodied carbon emission. Results are as follows:(1) From the perspective of total carbon emission, the amount of direct carbon emission in urban trade activities of Shanghai presents a trend of rising; by contrast, the intensity of direct carbon emission decreases year by year in the same period. The amount of embodied carbon emission first decreases and then increases slowly and finally increases in the last few years. The intensity of embodied carbon emission experiences a trend of reducing as a whole in this period, while in details it fluctuates from the year 2000 to 2005 and increases modestly from 2005 to 2012.(2) From the perspective of the industries’ relation, the influences of CO2 emission intensities from Oil processed manufacturing, metal smelting, the production and supply of water and building remain stable from 1997 to 2012. It is important to note that the influence coefficients of carbon emission intensity from these four industries are all larger than 1. By contrast, the influence coefficients of carbon emission intensity from most trades in the tertiary industry increases in this period. On the other hand, the sensitivity coefficients of oil processed manufacturing, metal smelting, power industry, transportation and storage keep better than average in the period.(3) Analyze the factors which influence the direct carbon emission in Shanghai from two dimensions:production and final demand. From the perspective of production, final demand structure and population are the main reasons that account for the increase of carbon emission in urban trade activities, whereas the changes of CO2 emission intensity, intermediate production structure and final demand per capital alleviate the increase of carbon emission to some extent. CO2 emission intensity exerts negative influences on the carbon emission in most primary and secondary industries and positive influences on the carbon emission in the tertiary industries and building. Population and end demand per capital leads to the increase of carbon emission in most industries. From the perspective of final demand, the trade activities between Shanghai and other districts are the main reasons leading to the change of carbon emission in Shanghai. The consumption of urban residences and government also play important roles in the change of carbon emission in Shanghai.(4) From the perspective of embodied carbon emission in export and import, total import and export is the most vital reason for the increase in embodied carbon emission. CO2 emission intensity, intermediate production structure and import structure are main reasons for decrease in embodied CO2 emission. CO2 emission intensity, intermediate production structure also decrease embodied carbon emission in export, but export structure increases carbon emission embodied in export. The result indicates that Shanghai has made progress in encouraging renewable energy, but economic dominated by heavy industry is still not suitable for low carbon development in Shanghai.According to the above analysis, corresponding policies are suggested for low carbon development of Shanghai.