A numerical study on indicators of long-range transport potential for anthropogenic particulate matters over northeast Asia

Kim, C.H.,Park, S.Y.,Kim, Y.J.,Chang, L.S.,Song, S.K.,Moon, Y.S.,Song, C.K. Pergamon Press ; Elsevier [distribution] 2012 Atmospheric environment Vol.58 No.-

Several indicators of the long-range transport potential of particulate matters have been proposed. These indicators can be used in the interpretation of the long-range transport process over northeast Asia. In order to characterize the indicators of long-range transport potential for days during which the concentration of particulate matter is high, we first classified these days during which PM<SUB>10</SUB> concentration was high into two extreme synoptic cases: long-range transport (LRT) case, and local emission with stagnation (LES) case. The classification employed here was on the basis of semi-empirical approach by employing the synoptic meteorological variables including relative vorticity, vorticity advection, and geostrophic wind speed/direction at a geopotential level of over 850 hPa. Simulation results of the two cases using the MM5-CMAQ modeling system were contrasted to determine suitable indicators of LRT potential. The results showed that the most effective indicator is the ratio of aromatic organic compounds to NO<SUB>x</SUB>, with correlation coefficients of 0.70 for toluene/NO<SUB>x</SUB>, and 0.72 for xylene/NO<SUB>x</SUB>. The ratios of N-containing species such as NO<SUB>x</SUB> (or NO<SUB>y</SUB>) to CO were the next best alternative indicators, with correlation coefficients of 0.53-0.62. The sulfur conversion ratios such as SO<SUB>4</SUB><SUP>2-</SUP>/(SO<SUB>2</SUB> + SO<SUB>4</SUB><SUP>2-</SUP>) and SO<SUB>4</SUB><SUP>2-</SUP>/SO<SUB>2</SUB> suggested good indicators for high sulfate condition (i.e., SO<SUB>4</SUB><SUP>2-</SUP> > 10 μg m<SUP>-3</SUP>). However, carbon aerosol ratio OC/EC did not show clearly separated regression lines distinguishing the LRT and LES cases, implying that ratios of both sulfur conversion in less polluted atmosphere and carbon aerosol should be considered carefully using them with confidence about their indication of the LRT potential over northeast Asia.

Analysis of Summertime Atmospheric Transport of Fine Particulate Matter in Northeast Asia

Hikari Shimadera,Hiroshi Hayami,Yu Morino,Toshimasa Ohara,Satoru Chatani,Shuichi Hasegawa,Naoki Kaneyasu 한국기상학회 2013 Asia-Pacific Journal of Atmospheric Sciences Vol.49 No.3

In Northeast Asia, the effect of long-range transport of air pollutants is generally pronounced in spring and winter, but can be important even in summer. This study analyzed summer-time atmospheric transport of elemental carbon (EC) and sulfate (SO42−) with the Community Multiscale Air Quality (CMAQ) model driven by the Weather Research and Forecasting (WRF) model. The WRF/CMAQ modeling system was applied to regions ranging from Northeast Asia to the Greater Tokyo Area in Japan in summer 2007. In terms of EC,while the model simulated well the effect of long-range transport, the simulation results indicated that domestic emissions in Japan dominantly contributed (85%) to EC concentrations in the Greater Tokyo. In terms of SO42−, the simulation results indicated that both domestic emissions (62%) and long-range transport from the other countries (38%) substantially contributed to SO42− concentrations in the Greater Tokyo. Distinctive transport processes of SO42− were associated with typical summer-time meteorological conditions in the study region. When a Pacific high-pressure system covered the main island of Japan, domestic emissions, including volcanic emission, dominantly contributed to SO42− concentrations in the Greater Tokyo. When a high-pressure system prevailed over the East China Sea and lowpressure systems passed north of Japan, synoptic westerly winds associated with this pressure pattern transported a large amount of SO42− from the continent to Japan. In addition, although heavy precipitation and strong wind decreased SO42− concentrations near the center of a typhoon, peripheral typhoon winds occasionally played an important role in long-range transport of SO42−.

Assessing the effect of long-range pollutant transportation on air quality in Seoul using the conditional potential source contribution function method

Jeong, Ukkyo,Kim, Jhoon,Lee, Hanlim,Lee, Yun Gon Elsevier 2017 Atmospheric environment Vol.150 No.-

<P>It is important to estimate the effects of the long-range transport of atmospheric pollutants for efficient and effective strategies to control air quality. In this study, the contributions of trans-boundary transport to the mean concentrations of SO2, NO2, CO, and PK in Seoul, Korea from 2001 to 2014 were estimated based on the conditional potential source contribution function (CPSCF) method. Eastern China was found to be the major source of trans-boundary pollution in Seoul, but moderate sources were also located in northeastern China. The contribution of long-range transport from Japan was negligible. The spatial distributions of the potential source contribution function (PSCF) values of each pollutant showed reasonable consistency with their emission inventory and satellite products. The PSCF values of SO2 and PM10 from eastern China were higher than those of NO2 and CO. The mean concentrations of SO2, NO2, CO, and PM10 in Seoul for the period from 2001 to 2014 were 534, 37.0, and 619.1 ppb, and 57.4 4 mu g/m(3), respectively. The contributions of long-range transport to the mean concentrations of SO2, NO2, CO, and PM10 in Seoul were 0.74, 3.4, and 39.0 ppb, and 12.1 mu g/m(3), respectively, which are 14%, 9%, 6%, and 21% of the mean concentrations, respectively. The annual mean concentrations of SO2 and NO2 followed statistically significant increasing linear trends (0.5 and 1.6 ppb per decade, respectively), whereas the trends in the annual mean concentrations of CO and PM10 were statistically insignificant. The trends in the ratio of the increased concentrations associated with long-range transport to the annual mean concentrations of the pollutants were statistically insignificant. However, the results indicate that the trans-boundary transport of 502, NO2, CO, and Milio from eastern China consistently affected air quality in Seoul over the study period (2001-2014). Regionally, the effects of the long-range transport of pollutants from Beijing and Harbin-Changchun on air quality in Seoul have become more significant over this period. (C) 2016 Elsevier Ltd. All rights reserved.</P>

Meteorological Mechanisms Associated with Long-range Transport of Asian Dust Observed at the West Coast of North America in April 2001

Song Sang-Keun,Kim Yoo-Keun,Moon Yun-Seob Korean Society for Atmospheric Environment 2004 한국대기환경학회지 Vol.20 No.E1

Meteorological mechanisms in association with long-range transport of Asian dust in April 2001 have been investigated using weather maps, satellite images, TOMS and surface $PM_{10}$ data, backward trajectories, plus modeling output results (geopotential heights, horizontal wind vectors, potential temperatures, and streamlines). The results indicated that long -range transport of Asian dust to the west coast of North America was associated with strong westerlies between the Aleutian low and the Pacific high acting as a conveyor belt. Accelerating westerly flows due to cyclogenesis at the source regions over East Asia transported pollution from the continent to the central Pacific. When the system reached the Aleutian Islands, the intensity of troughs and the westerlies were amplified in the North Pacific. Thereafter the winds between the Aleutian Islands and the Pacific Ocean were more intensified from the air flow transport of the conveyor belt. Consequently, the strong wind in the conveyor belt enhanced the dust transport from the Pacific Ocean to the west coast of North America. This was evidenced by $PM_{10}$ concentration (maximum of about $100{\mu}g\;m^{-3}$) observed In California. Further evidence of the dust transport was found through the observation of satellite images, the distribution of TOMS aerosol index, and the analyses of streamlines and backward trajectories.

한반도 서해상으로 장거리 이동하는 SO₂의 농도 및 연직분포 특징

한진석,안준영,홍유덕,공부주,이석조,선우영 한국대기환경학회 2004 한국대기환경학회지 Vol.20 No.5

This study was carried out to understand long-range transport of SO₂ using aircraft measurements for the identification of it's horizontal and vertical concentration and distribution pattern. Thirteen missions of aircraft measurements have been done around 37˚00′/124˚30′ from October 1997 to November 2001. Concentrations of SO₂ was 1.5~2.0 ppb in the below mixing layer, 0.6~1.1 ppb in the above mixing layer. SO₂was found to be relatively higher than marine background level, 0.08~0.2ppb, indicating the western coast being influenced by long-range transport except for the summer season. The vertical distribution of SO₂was classified into 3 groups using its vertical sounding and meteorology pattern; the first is linear decay pattern, the second is exponential decay pattern, and the last is gaussian distribution pattern in the below mixing layer, 2 patterns of linear decay and gaussian distribution patterns in the upper layer. It is founded that vertical distribution pattern is strongly dependent on meteorological condition, for example atmospheric stability and predominant air flow.

Determination of the inter-annual and spatial characteristics of the contribution of long-range transport to SO₂ levels in Seoul between 2001 and 2010 based on conditional potential source contribution function (CPSCF)

Jeong, U.,Lee, H.,Kim, J.,Kim, W.,Hong, H.,Song, C.K. Pergamon Press ; Elsevier [distribution] 2013 Atmospheric environment Vol.70 No.-

In this paper, we introduce a new method to estimate the change in mean mixing ratio of a target species at a receptor site due to the contribution of the long-range transport (CLRT). We applied our method to determine inter-annual and inter-seasonal variations in the CLRT of SO<SUB>2</SUB> in Seoul, a major megacity in northeast Asia, during the period from 2001 to 2010. The major potential source areas of SO<SUB>2</SUB> for the 2001-2010 period were located in East China according to the potential source contribution function (PSCF) maps. The CLRT of SO<SUB>2</SUB> in Seoul was estimated to range from 0.40 to 1.03 ppb, which accounted for 8-21% of the ambient mean SO<SUB>2</SUB> mixing ratio in Seoul. The inter-annual variations of estimated CLRT of SO<SUB>2</SUB> was well correlated with those of the total emissions in China during the period of 2001-2008 (R = 0.85). We found that both local emissions from around Seoul and long-range transport from East China, especially the Shandong peninsula, affected the SO<SUB>2</SUB> mixing ratio in Seoul throughout the decade of study. The CLRT of SO<SUB>2</SUB> in Seoul increased after 2007 even though the total emissions of SO<SUB>2</SUB> by China have been decreasing since 2006. The CLRT of SO<SUB>2</SUB> in Seoul was high in spring and winter, which can be attributed to enhanced SO<SUB>2</SUB> emissions in East China during these seasons and a dominant westerly wind. The CLRTs of SO<SUB>2</SUB> accounted for 15, 11, 4, and 12% of the seasonal mean SO<SUB>2</SUB> mixing ratio in spring, summer, fall, and winter, respectively. The uncertainty ranged from 24 to 62% of the estimated CLRT values.

Numerical Analysis of Wintertime Air Pollution in East Asia Region Using Long-Range Transport Model

Jang, Eun-Suk The Korean Environmental Sciences Society 2000 Environmental sciences Vol.4 No.2

In order to understand the wintertime intermittent characteristics of the trans-boundary air pollutant transport observed in East Asia, a numerical simulation of the long-range transport of pollutants was applied using an atmospheric transport model(STEM-II). The numerical simulation was carried out for the entire month of January 1997 and specific atmospheric aerosol (including sulfate, nitrate, and other ion compounds0 observation data were compared from four observation sites(Cheju Island, Kanghwa Island, Dazaifu, and Fukue Island). The observation data revealed that concentration peaks were intermittently observed at 3 to 4-day intervals plus the four observation sites exhibited a very similar spatial variation. The horizontal and spatial scale of the heavily polluted air masses was analyzed based on numerical results. The mechanism of the intermittent transport of air pollutants was clearly explained by a comparison of the observed data with the numerical output. It was found that the wind pattern variations associated with the synoptic scale pressure system changes play an extremely important role in the transport of pollutants in this region.

연구 논문 : OMI 이산화황자료와 HYSPLIT 역궤적 계산을 이용한 동북아지역의 장거리 수송되는 이산화황 유입량 산출

박준성 ( Jun Sung Park ),홍현기 ( Hyun Kee Hong ),최원이 ( Wo Nei Choi ),이한림 ( Han Lim Lee ) 대한원격탐사학회 2014 大韓遠隔探査學會誌 Vol.30 No.6

In this present paper, we, for the first time, calculated SO2 inflow from China to Korea peninsula based on OMI SO2 products and HYSPLIT (Hybrid Single Particle Lagrangian Integrated Trajectory Model) backward trajectory calculations. The major factors used to estimate SO2 flux are long range transported SO2 concentration, transport speed of air mass, and thickness of transported air mass layer. The mean and maximum SO2 fluxes are estimated to be 0.81 and 2.11 g·m-2·h-1, respectively based on OMI products while, those of SO2 fluxes are 0.50 and 1.18 g·m-2·h-1 respectively using insitu data obtained at the surface. For most cases, larger SO2 inflow values were found at the surface than those estimated for the air mass layer which extends from surface up to 1.5 km. However, increased transport speed of air mass leads to the enhanced SO2 flux at the altitude up to 1.5 km at the receptor sites. Additionally, we calculate uncertainties of SO2 flux using error propagation method.

Long-range Transport Mechanisms of Asian Dust associated with the Synoptic Weather System

Kim, Yoo-Keun,Lee, Hwa-Woon,Moon, Yun-Seob,Song, Sang-Keun The Korean Environmental Sciences Society 2001 Environmental sciences Vol.10 No.4

The long-range transport mechanisms of Asian dust were analyzed based on the synoptic weather system and numerical simulation by using NCEP/NCAR reanalysis and TOMS data during the periods of 1996-2001. We classified the whole weather types of eastern Asia during spring and created the representative weather types during the yellow sand events using cluster analysis and weather charts for the last 6 years(1996~2001). These long-range transport mechanisms were related to various pressure patterns including high and low, trough and ridge, and upper-level fronts. Case studies of the yellow sand events have performed by the simulation of MM5 with meteorological elements such as the horizontal wind of u and v component, potential temperature, potential vorticity, and vertical circulation during the episodic days(2~8 March 2001). In addition, the origin of the long-range transport was examined with the estimation of backward trajectory using HYSPLIT4 Model. In this paper, we concluded that three weather types at 1000 hPa, 850 hPa, 500 hPa, and 300 hPa levels were classified respectively. The dominant features were the extending continental outflow from China to Korea at 1000 hPa and 850 hPa levels, the deep trough passage and cold advection at 500 hPa and 300 hPa levels during the yellow sand events. And also, we confirmed the existence of pola $r_tropical jets in the upper-level, the behavior of potential vorticity over Korea, the estimation of potential vorticity through vertical cross section, and the transport of yellow sand through backward trajectories.es.

A Comparison of Particulate-Bound Polycyclic Aromatic Hydrocarbons Long-Range Transported from the Asian Continent to the Noto Peninsula and Fukue Island, Japan

Lu Yang,Ning Tang,Atsushi Matsuki,Akinori Takami,Shiro Hatakeyama,Naoki Kaneyasu,Edward G. Nagato,Kei Sato,Ayako Yoshino,Kazuichi Hayakawa 한국대기환경학회 2018 Asian Journal of Atmospheric Environment (AJAE) Vol.12 No.4

This is the first comparative study to examine two different background monitoring sites in Japan to compare differences in the concentration and composition of long-range-transported polycyclic aromatic hydrocarbons (PAHs) from the Asian continent. This study chose the Noto Peninsula (the Kanazawa University Wajima Air Monitoring Station; WAMS) and Fukue Island (the Fukue-jima Atmosphere and Aerosol Monitoring Station; FAMS) to compare 10 weekly periods in 2009 and 2010 from autumn to spring, seasons that are strongly influenced by the Asian continent. The PAHs concentration differed significantly for most periods at these two sites. The backward trajectory analysis found that the low height of the air mass may cause the low concentration and the similar air mass condition could result in the similar concentration. The concentration of long-range-transported PAHs depended more on the source of the coal combustion areas such as Northeast China in heating period.