Traffic Pollution in Xi’an city, P.R.China (BAQ 2002)

Xi'an city is the key economic center and transportation axis for the central and western region of China. It is better known throughout the world for its historical relics and antiquities. Air quality in Xi’an has bee moderately to heavily-polluted since the last decade. In this article, the author makes a quantitative analysis of traffic emission and its effects on the urban environment in Xi'an. Based on the estimation done in this study, the share of NOx, HC and CO pollution from urban traffic in Xi’an stands at around 46.43%, 62.47 % and 51.64 % at present. The study also shows that vehicle emission of NOx will increase even if the strict vehicle emission standards are going to be adopted, the share of NOx emission from traffic will increase to 63.38 % by 2010. The introduction of new standards will reduce HC and CO emission by a large degree by 2005, but with the increase of vehicle population and kilometers driven, their emission will slightly increase after 2005