GAW Report No. 205 - IGAC Project

CHAPTER 3 - ASIAProblems remainingThe success of air quality improvements for Beijing Olympic Games proved that thereduction of precursors of ozone and fine particles were correct in the short-term, but will be toughin long term. Xu et al., [2008] used a 3D air quality model to show that the Beijing urban area was ina VOC-limited regime, while the downwind area changed gradually to a NO X -controlled process.Furthermore, 35–60% of the ozone during pollution episodes at the Beijing Olympic Stadium wasfound to come from sources of ozone precursors outside Beijing, e.g. from Hebei Province andTianjin [Streets et al., 2007]. Fine particles have significant origins of both primary emissions andsecondary production and therefore are not very well understood yet for Beijing. Furthermore, thegrey haze and fine particles issue is known to be a regional problem. Therefore, a regionalperspective is required to provide efficient control measures to overcome ozone and fine particleproblems. A better understanding of the interaction between the formation of ozone and fineparticles, shown in Figure 11, is essential in order to implement effective measures to abate bothfine particle and the ground-level ozone pollution in the next 20 years.Figure 11 - The change of peak concentrations of ambient ozone levels at Zhongguancun site in Beijingduring ozone episodes [Shao et al., 2006]3.4 DELHI, INDIADelhi, the capital city of India, hosted the Commonwealth Games in October 2010 (CWG2010). With the Games, the debate on air quality in Delhi and athletes health during the Games tookcenter stage, similar to the debates on air quality in Beijing before and during the Olympics Gamesin 2008 [UNEP, 2009].The National Capital Region (NCR) of Delhi has grown rapidly in the past two decades. Itnow covers an estimated area of 900 km 2 , which includes new townships and satellite centers suchas Noida, Gurgaon, Ghaziabad, and Faridabad, all of which are a combination of informationtechnology firms and industrial clusters (a graphical representation of the NCR is presented inFigure 12). In 2007, the population of NCR was estimated at 16 million. It is expected to reach 22.5million in 2025 [UNHABITAT, 2008].73