GAW Report No. 205 - IGAC Project

CHAPTER 3 - ASIAFigure 36 - Mass concentrations of carbonaceous and ionic species of total suspended particles during level flights madeat 300, 600, and 1300 m on 19 March 2003. ME0307, ME0308, and ME0309 correspond to flights (~2 h) that took off at 08:30,12:30, and 16:30 local time, respectively. Reproduced by permission of Elsevier from Hasegawa, S., S. Wakamatsu,T. Ohara, Y. Itano, K. Saitoh, M. Hayasaki, and S. Kobayashi (2007), Vertical profiles of ultrafine to supermicron particlesmeasured by aircraft over Osaka metropolitan area in Japan [Hasegawa et al., 2007]Traffic-related air pollutants have been monitored near major roads at 10 sites in the Kanto,Chubu, and Kansai areas by the Ministry of the Environment of Japan (MOE) since 2005 [e.g.,Naser et al., 2009]. Nitrogen oxides (NO X ), suspended particulate matter (SPM, 100% cut-offaerodynamic diameter at 10 mm), PM 2.5 , and BC were instantaneously and continuously monitoredat four stations at various distances (about 5, 35, 70, and 150 m) from each of the target roads.Naser et al. [2009] used these measurement data and a Gaussian plume model to derive theemission factor of BC to SPM at roadside sites. They obtained good agreement between theobserved and estimated ratios with a proportionality constant (BC/SPM) of 0.4, indicating that thesame BC/SPM emission ratio.MOE also measured VOCs (63 compounds) at four urban sites in the Kansai areathroughout 2004 [Sasaki and Sakamoto, 2007]. Five samples were collected at each site in everyseason. The analysis, made by using a Chemical Mass Balance model, suggested that gasolinevapour and gasoline vehicle exhaust were significant sources of atmospheric VOCs.Remaining problemsThe effects of regulations of NO X , VOCs, and PM emissions on O 3 and PM concentrationsshould be assessed by using the monitoring data from MOE and various research groups. Also,source contributions of O 3 and PM should be evaluated by analyzing these measurement data incombination with model simulation. Because the Osaka area is closer to the Asian continent thanTokyo, it is more strongly affected by the outflow of Asian pollutants. More systematic assessmentof the effect of transboundary pollution on pollutants in the Kansai area is needed.3.10 PEARL RIVER DELTAIntroduction and specific features of the cityThe Pearl River Delta (PRD) situated at 21 ° 17´–23 ° 56´N and 111 ° 59´–115 ° 25´E is connectedto the South China Sea. The PRD region covers 4.17 × 10 4 km 2 with a population of over 38 million.Most of the PRD region includes Guangdong Province and two Special Administrative Regions of107