Aerial Observation of Aerosols Transported from East Asia — Chemical Composition of Aerosols and Layered Structure of an Air Mass over the East China Sea

In this study, the regional transport and characteristics of PM 2.5 pollution were examined through a case study in Beijing, China. The results from an intensive monitoring program indicate that the inorganic particles (sulfate, nitrate, and ammonium), organic carbons, and the elements accounted for 35.5, 24.2, and 15.3% of the total PM 2.5 on an annual average basis, respectively. The proportions of such PM 2.5 components also showed clear seasonal variations. An integrated MM5-CMAQ modeling system was then developed to examine the regional transport of PM 2.5 and its components in Beijing within four typical months of 2010. The results indicate that the annual average total trans-boundary contribution ratio (TBCR) is 42.2, 46.3, 77.4, and 61.6% for the concentrations of PM 2.5 , sulfate, nitrate, and ammonium, respectively. A logarithmic relationship was found between the total TBCR and the PM 2.5 concentrations in Beijing for different seasons. Further investigations showed that trans-boundary transport played a major role in Beijing's PM 2.5 concentrations during the period of high pollution levels, with an annual average TBCR of 54.6%. As a result, the control of PM 2.5 pollution in Beijing needs effective cooperation between Beijing and its surrounding regions, especially during periods of heavy pollution.

Section: Introductionmentioning

confidence: 92%

A Monitoring and Modeling Study to Investigate Regional Transport and Characteristics of PM2.5 Pollution

Lang

Cheng

et al. 2013

“…While AODs were pretty high in the North (such as the north Shanghai, Jining district in Shandong and Maanshan district in Anhui) even in the cleanest year of 2000 and 2003. Therefore, aerosol loadings in the North might associate to human activities induced constructive soil, traffic dust and industrial emissions as well as dust storms from north China (Hatakeyama et al, 2011), and those in the South might associate to natural emissions.…”

Section: Inconsistent Variation Of Aerosol Loading Over Northern and mentioning

confidence: 99%

Study on Long-term Aerosol Distribution over the Land of East China Using MODIS Data

Geng

et al. 2012

East China is among the fastest developing area in Asia, where atmospheric aerosol loading is high due to heavy urban and industrial emission. The Moderate Resolution Imaging Spectroradiometer (MODIS) level 2 aerosol products (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007) were used to study aerosol spatial and temporal distributions, as well as their variations with local meteorological conditions over East China. By combining Aerosol Optical Depth (AOD) and aerosol Fine Mode Fraction (FMF), we found that the urban/industrial aerosol and soil dust are possibly two dominant species over northern part, whereas continental and marine aerosols possibly dominate the southern part of East China. Both annual mean AOD and area with high AOD increased from 2000 to 2007, with the largest increase seen in Yangtze River Delta region (YRD). In summer, AOD in East China reached the maximum of about 0.8 in YRD, dominated by fine mode particles. The minimum AOD occurred in winter with mostly coarse mode particles. Local aerosol properties were analyzed in three typical zones: the northern dry zone (I), the central urban/industrial zone (II) and the southern natural background zone (III). Monthly mean AODs in zone I and II were above 0.5 throughout the entire year, with the maximum AOD in June. High FMFs in this period indicated heavy urban and industrial pollution. Monthly mean AODs and FMFs in zone III reached maximum of 0.51 in April and September (up to 90.7%) respectively. High AOD in spring in zone III appears mostly due to the long-range dust transport from the North.

“…In recent years, long-range transport of air pollutants has often been observed around the East China Sea and the Japan Sea regions in winter and spring Takami et al, 2007;Yang et al, 2007;Hatakeyama et al, 2011;Lai et al, 2011;Kwon et al, 2012). The emissions of carbonaceous aerosols, for example, particulate polycyclic aromatic hydrocarbons (PAHs) and n-alkanes, have also increased (Su et al, 2006;Zhang and Tao, 2009;Inomata, 2012).…”

Section: Introductionmentioning

confidence: 99%

Transported and Local Organic Aerosols over Fukuoka, Japan

Sato

Takami

Irei

et al. 2013

Self Cite

In order to understand transported and local pollution in an urban area that are strongly affected by long-range transport of air pollution, daily concentrations of 15 polycyclic aromatic hydrocarbons (PAHs) and 20 n-alkanes in the total suspended particles were simultaneously measured at sites in Western Japan on Fukue Island (FI), located downwind of mainland East Asia, and Fukuoka City (FC), a megacity close (< 200 km) to the FI site, in spring and winter 2010 and summer 2011. The average total PAH concentration observed at the FC site (2.93 ± 2.17 ng/m 3 ) was higher than that at the FI site (1.78 ± 1.70 ng/m 3 ). The average total n-alkane concentration at the FC site (34.7 ± 21.8 ng/m 3 ) was also higher than that at the FI site (12.2 ± 9.2 ng/m 3 ). However, the total PAH and n-alkane concentrations measured at the FI site were considerably high, despite its remote location. The seasonal changes in the specific PAH ratios, used to determine the source of pollutants, were similar between the FC and FI sites. The average fluoranthene/(fluoranthene + pyrene) ratio was 0.57-0.65 in winter and spring and 0.48-0.51 in summer. PAHs observed at both sites mainly originated from coal or biomass combustion in spring or winter, whereas those were affected by petroleum combustion as well as coal and biomass combustion in summer. These field results show that pollutants transported from mainland East Asia make a significant contribution to the total PAHs and n-alkanes at the FC site in the winter and spring seasons.