• Journal of Environmental Science International
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• v.22 no.6
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• pp.651-666
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• 2013

This study introduces a novel approach to the differentiation of two phenomena, Asian Dust and haze, which are extremely difficult to distinguish based solely on comparisons of PM10 concentration, through use of the Optical Particle Counter (OPC), which simultaneously generates PM10, PM2.5 and PM1.0 concentration. In the case of Asian Dust, PM10 concentration rose to the exclusion of PM2.5 and PM1.0 concentration. The relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration were below 40%, which is consistent with the conclusion that Asian Dust, as a prime example of the coarse-particle phenomenon, only impacts PM10 concentration, not PM2.5 and PM1.0 concentration. In contrast, PM10, PM2.5 and PM1.0 concentration simultaneously increased with haze. The relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration were generally above 70%. In this case, PM1.0 concentration varies because a haze event consists of secondary aerosol in the fine-mode, and the relative ratios of PM10 and PM2.5 concentration remain intact as these values already subsume PM1.0 concentration. The sequential shift of the peaks in PM10, PM2.5 and PM1.0 concentrations also serve to individually track the transport of coarse-mode versus fine-mode aerosols. The distinction in the relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration in an Asian Dust versus a haze event, when collected on a national or global scale using OPC monitoring networks, provides realistic information on outbreaks and transport of Asian Dust and haze.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2003.10a
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• pp.187-187
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• 2003

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.3
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• pp.148-156
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• 2011

The purpose of this study is to analyze the patterns of forest fire possibly related with Asian dust event and carry out a correlation analysis between forest fire occurrence and existence or not of the Asian dust event during dry seasons i.e. February to May in 2000 to 2008. To study the correlation of forest fire and Asian dust, we surveyed information of Asian dust observations, forest fire statistics, fire danger rating index, weather data such as temperature, relative humidity and wind speed of the day occurring the forest fire. As a consequence of analysis, the regional frequency of Asian dust was the highest in Gyeonggi and Chungbuk divisions. Frequencies of forest fire occurrence by the Asian dust events were the highest in the day before three days of the Asian dust event. The highest frequent regions of forest fire occurrence were district of boundary line between Gyeonggi and Western of Gangwon, Chungbuk and Gyeonbuk inland. The correlation between forest fire and fire danger rating index showed the high correlation with the day before three days and after three days of the Asian dust event. These correlation coefficients were 0.50038 and 0.53978 to 1% significance level. The result of analysis between the frequency of forest fire occurrence and wind speed had a highly negative relationship at all the Asian dust days, the day before and after three days. The correlation coefficients had been -0.58623 to -0.61245 to 1% significance level. Relative humidity showed a little of negative relationship with forest fire occurrence in -0.2568(p ${\leq}$ 0.01) for the Asian dust day and -0.35309(p ${\leq}$ 0.01) for next three days. Moreover, at the day before three days of Asian dust events, it was -0.23701 to 1% significance level. However, the mean temperature did not correlate with frequency of forest fire occurrence by Asian dust events at all.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.3
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• pp.255-271
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• 2011

ACE-Asia (Asian Pacific Regional Aerosol Characterization Experiment) in spring 2001 was a turning point to trigger international research interest on Asian dust (AD). This basically arose from the lack of research on AD, the important natural phenomenon to characterize the Northeast Asia. In contrast, health risk related to AD has been the primary concern in Korea. Although due in part to severe AD events of 2001~2002, research and mitigation measures on AD in Korea are typically based on the assumption that AD events are increasing in frequency and severity. However, contrary to the trend in Korea, the number of AD days and emission amounts of AD in China have decreased since 1980s. This paper reviews the impacts of AD on ambient air quality and variations in toxic substances during the AD event, reflecting the concern in Korea. While a great amount of dust particles flow into Korea during the AD event, a considerable amount of dust particles are locally generated as well. Since dust particles are mixed with toxic substances as they pass over polluted areas, the levels of toxic substances become lower in dust particles that do not pass over polluted areas. Broadening the research scope on AD is warranted to understand the AD as an important natural phenomenon, irrespective of its associated health risk.

• Asian Journal of Atmospheric Environment
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• v.8 no.3
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• pp.154-161
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• 2014

The present study was undertaken to evaluate the chemical characteristics of Asian dust (hereafter called "AD") particles with the aid of the most advanced micro-PIXE (Particle-induced X-ray emission) analytical technique. To this end, size-selected particles were sampled on a rural peninsula of Korea (Byunsan, 35.37N; 126.27E) during AD and non-AD periods in 2004. The coarse particle (> $2{\mu}m$) number density during an AD event were 170 times higher than those of the non-AD counterpart. The average net-count of silica in individual particles collected on AD event was roughly 11 times higher than that of non-AD counterpart. The X-ray net-counts of trace elements (Zn, Co, Mn, and V) were also considerably high in AD relative to the non-AD day. Particle classification based on the inter ratio analysis of elemental net-count suggests that a large portion of the coarse particles collected during AD event underwent chemical transformation to a certain degree. The visual interpretation of micro-PIXE elemental maps and elemental localization data in and/or on individual AD particles clarified the internal mixture of AD particles with sea-salt and artificial metallic particles.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.5
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• pp.434-448
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• 2014

The aerosol characteristics between haze episode and Asian dust event were identified in January and March, 2013 in Gwang-ju of Korea to investigate the metal elements, ionic concentrations and carbonaceous particles of $PM_{2.5}$ and $PM_{10}$. In the haze episode, the concentrations were increased 1~3.2 times of ionic species and 1.6~2.7 of metal elements. Especially, the concentration of $NO{_3}{^-}$, $SO{_4}{^2-}$ and $NH{_4}{^+}$ consists of 50 percent in ionic species during haze episode that was higher than Asian dust event. This suggests that secondary aerosols from anthropogenic air pollution were mainly contributed by haze episode. During the Asian dust event, increase of metal concentrations was higher than haze episode because of remarkable increase of Ti, K and Fe originated from soil. The concentrations of carbonaceous particles were increased 2.5 times during haze episode, and 2.4 times of OC and 2.1 times of EC during Asian dust event in $PM_{2.5}$. However, these aerosol mass concentration does not affect the OC/EC ratio. The average equivalence ratios of cations/anions in $PM_{2.5}$ were 0.99 in haze episodes and 0.94 during non-event day. The neutralization factor of $NH_3$ was higher than that of $CaCO_3$. Futhermore, $NH{_4}{^+}$ aerosol was aged due to atmospheric stagnation that might be affected by the haze episode.

• Analytical Science and Technology
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• v.36 no.4
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• pp.191-197
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• 2023

Radioactivity concentrations for natural radionuclides were determined from fine dust samples collected in Jeju, Korea according to atmospheric events (Asian dust, haze, fog-mist, and non-event), and radium equivalent activity was calculated. The mean atmospheric radioactivity concentrations for ²³⁸U, ²³²Th, and ⁴⁰K in 127 fine dust samples were 0.49, 0.24, and 7.23 µBq m^-3, respectively, and the radium equivalent activity was 33.25 Bq kg^-1. The mean concentrations of ²³⁸U and ²³²Th in the fine dust during the Asian dust period were 1.31 and 1.60 µBq m^-3, respectively, above the global average, while the values for the other three atmospheric events were lower. The ratio of ²³²Th/²³⁸U radioactivity during the Asian dust period was 1.22, higher than the ratio for the other three atmospheric events.

• Atmosphere
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• v.20 no.3
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• pp.273-286
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• 2010

The northeast part of China(hereafter Manchuria) is one of Asian dust source regions along with Gobi, Inner Mongolia and Loess Plateau. In this study, a geographical survey over the area was carried out to determine its soil characteristics in June 2009. It revealed that some parts of the area, especially near Keerchin desert, consist of alkali clay soil mixed up with sand. Manchuria, where is a vast cornfield, can be a potential source region of Asian dust from fall to following spring after harvesting. The frequency of Asian dust over the region from 1996 to 2009 was examined using 3-hourly GTS SYNOP data and it showed that the occurrence of Asian dust over the region is high in the springtime. It was also revealed that snow cover is the key parameter affecting on the frequency through the analysis of NCEP reanalysis data. To scrutinize the path and structure of Asian dust from Manchuria, the event on 3~4 April 2008 and 25 January 2010 were intensively investigated with regard to features of synoptic weather patterns, satellite imagery, airstream, naked eye-observations, concentrations of PM10, 2.5 and 1.0. For this case, the Asian dust from the area reached to Korea less than a day. However, the duration time of the dust in Korea was short (< 7 hours). The average of hourly PM10 reached up to $340{\mu}g/m^{3}$ at Baengnyeondo during the period. The high PM2.5 and PM1.0 concentrations were also observed at several sites in Korea, indicating that air pollutants could be transported along with the dust.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.2
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• pp.199-210
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• 2013

Detailed 3 dimensional structure of Asian dust plume has been analyzed from the retrieved aerosol data from two different satellites which are the Korea's $1^{st}$ geostationary satellite, namely the Communication, Ocean, Meteorological Satellite (COMS) spacecraft launched in 2010, and the NASA's Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO). COMS spacecraft provides the first time resolved aerial aerosol maps by the systematically well-calibrated multispectral measurements from the Geostationary Ocean Color Imager (GOCI) instrument. GOCI data are used here to evaluate intensity, spatial distribution, and long-range transport of Asian dust plume during 1~2 May 2011. We found that the strong Asian dust plume showing AOT of 2~5 was lofted to the altitude around 2~4 km above the Earth's surface and transported over Yellow Sea with a speed of about 25 km/hr. The CALIPSO extinction coefficient and particulate depolarization ratio (PDR) profiles confirmed that nonspherical dust particles were enriched in the dust plume. This study is a first example of quantitative integration of GOCI and CALIOP measurements for clarifying the overall structure of an Asian dust event.

• Korean Journal of Remote Sensing
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• v.26 no.4
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• pp.387-394
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• 2010

There has been an increasing trend in damaging by the Asian dust in spring. The continuous monitoring of the dust event with IR channels in geostationary satellite is very useful for forecasting and preventing the event. However, the monitoring with the IR channels revealed various problems associated with sensitivity. To eliminate these problems, we introduced a new concept of monitoring by constructing the background threshold values (BTV) and aerosol index (AI). This paper is about to test the reliability of this concept by applying to geostationary satellite, MTSAT-1R.