Concentration Variations in Particulate Matter in Seoul Associated with Asian Dust and Smog Episodes

Abstract

Particulate species were measured in April-May 2003 at two sites, one in the megacity of Seoul and the other in the Deokjeok Island to the west of Seoul, to examine the effects of long-range transport under the influence of prevailing westerlies. The effects of Asian dust were observed in April, and a severe smog episode occurred in late May. During May, all air pollutants showed negative correlations with wind speed at Seoul, particularly for NO 2 and CO, a large proportion of which result from vehicle emissions. SO 4 2-continued to increase in association with an inflow of air pollutants from China with heavy use of coal, with fluctuations depending on wind speed. The smog episode in late May occurred as emissions from Siberian forest fires were superimposed on pollutant inflows from China that had persisted since early May and local emissions accumulated under stagnant conditions. During the episode, Siberian forest fires increased K + while local emissions primarily from vehicles increased NO 3 -, OC, and EC. The effects of an inflow of air pollutants from the outside were significant at Deokjeok, with small local emissions, resulting in substantial increases in Ca 2+ during the Asian dust event and SO 4 2-during the smog episode, compared to those at Seoul. Because both sites were strongly influenced by the effects of long-range transport in May, PM 2.5 along with SO 4 2-and K + exhibited a strong correlation between Seoul and Deokjeok.

Spatial and Temporal Variation of PM2.5 and Atmospheric PCDD/Fs in Northern Taiwan during Winter Monsoon and Local Pollution Episodes

“…Accordingly, PCDD/Fs might have travelled from somewhere in northern China to the coastal regions of northern and southern China to Taiwan, suggesting that these pollutants resulted in transboundary pollution because of air-mass transport (Chen et al, 2015;Yang et al, 2017), causing an increase of PCDD/F concentration on the island. A similar phenomenon was also observed before in Korea (Lee et al, 2007;Ghim et al, 2017). PCDD/Fs might also have been brought by air currents from the Pacific Ocean, which are active in the east of Taiwan.…”

Long-Range Transport Influence on Key Chemical Components of PM2.5 in the Seoul Metropolitan Area, South Korea, during the Years 2012–2016

“…In Northeast Asia, in particular, precursor emissions and meteorological conditions change markedly depending on the season. Thus, the concentration and composition of PM 2.5 show clear seasonal variations [11,12]. in individual PM 2.5 major chemical components and quantifies foreign impacts, using air-quality modeling; and, finally, Section 4 summarizes our findings.…”

“…The zero-out contribution (ZOC) [65] represents the change in concentration when the emission reduction rate of the target area is assumed to be 100%, using the derived sensitivity factor. ZOC was Atmosphere 2020, 11,48 6 of 19 used as the concentration impact of the target emissions in this study. The impact of Chinese emissions on the PM 2.5 concentration in SMA was calculated by adding the ZOCs of each component, in the following manner:…”

“…Atmosphere 2020, 11 Figure 3A shows the frequency distribution of PM 2.5 concentrations during the cold (winter and spring) and warm seasons (summer and autumn). Frequencies are shown as probabilities to account Atmosphere 2020, 11, 48 8 of 19 for the varying amounts of data available in the cold and warm seasons.…”

Characterisation of particulate matter at a high-altitude site in southwest India: Impact of dust episodes

“…Therefore, seven day air mass backward trajectories at a height of 3000 m above the ground level were studied using the HYSPLIT model. This model describes the information on the latitude, longitude and altitude of air mass pathways and is useful to identify the probable source regions (Lelieveld et al 2002;Oanh et al 2016;Ghim et al 2017). Schauer et al (2016) have reported the impact of long-range transport of Saharan dust along with emissions from wildfires over a high-altitude site in Austrian Alps.…”