Authors：Feng Han，Rui Xie，Yue lu，Jiayu Fang, Yu Liu

Abstract：This study expounded the mechanism of the effects of urban agglomeration economies on carbon emissions based on the theory of agglomeration economies. Based on the STIRPAT model, we built an econometric model. We then used the method of spatial econometrics to estimate the effects of urban agglomeration economies on carbon emissions through matching the firm-level data and panel data of 283 prefecture level and above cities from 2003 to 2010 in China. The results reveal that both specialization and diversification agglomeration can significantly promote carbon emission reduction in local and neighboring cities through the agglomeration externalities. Specifically, specialization agglomeration of low-end technology industry has significant reduction effects on carbon emission of local and neighboring cities in most cases, while the diversification agglomeration has increased it. The specialization and diversification agglomeration of midrange technology industry have increased the carbon emissions of the local and neighboring cities. Furthermore, the specialization and diversification agglomeration of high-end technology industry have significant carbon emission reduction effects in varying degrees for the local and neighboring cities.

Key Words：Specialization agglomeration;Diversification agglomeration;Carbon emissions;Spatial spillover effects