• 한국대기환경학회지
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• 제18권4호
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• pp.275-284
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• 2002

Atmospheric concentrations of organochlorine pesticides (OCPs) in Seoul, South Korea between July 1999 and May 2000 were determined to investigate concentration distribution in air, relationship between concentrations and meteorological conditions, and apportionment of sources e.g. local sources (air- surface exchange) and long range transport. Endosulfan and $\alpha$-HCH were the highest concentrations in atmosphere with values typcally ranging from 10s to l00s of pg/㎥. These high concentrations may be attributed to their usage, period and chemical property (Koa). All OCPs also showed elevated levels during the summer and were positively correlated with temperature. This would suggest that a seasonal enhancement was due to (re)volatilization from secondary sources and application during the warmer months. The temperature dependence of atmospheric concentrations of OCPs were investigated using plots of the natural logarithm of partial pressure (In P) vs reciprocal mean temperatures (1/T), and environmental phase-transition energies were calculated for each of the pesticides. For OCPs, temperature dependence was statistically significant (at the 99.99% confidence level) and temperature accounted for 35~95% of the variability in concentrations. The relatively higher slopes and phase-transition energies for $\alpha$-, ${\gamma}$-chlordane, endosulfan and endosulfan sulfate suggested that volatilization from local sources influenced their concentrations. The relatively lower those for $\alpha$-, ${\gamma}$-HCH, p, p'-DDE and heptachlor epoxide also suggested that volatilization from local sources and long range transport influenced their concentrations.

• 한국대기환경학회지
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• 제33권2호
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• pp.174-183
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• 2017

The background level and timely variation characteristics of atmospheric $^{222}Rn$ concentrations have been evaluated by the real time monitoring at Gosan site of Jeju Island, Korea, during 2008~2015. The average concentration of atmospheric radon was $2,480mBq\;m^{-3}$ for the study period. The cyclic seasonality of radon was characterized such as winter maximum and summer minimum, consistent with the reduction in terrestrial fetch going to summer. On monthly variations of radon, the mean concentration in October was the highest as $3,041mBq\;m^{-3}$, almost twice as that in July ($1,481mBq\;m^{-3}$). The diurnal radon concentrations increased throughout the nighttime approaching to the maximum ($2,819mBq\;m^{-3}$) at around 7 a.m., and then gradually decreased throughout the daytime by the minimum ($2,069mBq\;m^{-3}$) at around 3 p.m. The diurnal radon cycle in winter showed comparatively small amplitude due to little variability in atmospheric mixing depth, conversely, large amplitude was observed in summer due to relatively a big change in atmospheric mixing depth. The cluster back-trajectories of air masses showed that the high radon events occurred by the predominant continental fetch over through Asia continent, and the radon concentrations from China continent were about 1.9 times higher on the whole than those from the North Pacific Ocean. The concentrations of $PM_{10}$ also increased in proportion to the high radon concentrations, showing a good linear correlation between $PM_{10}$ and radon concentrations.

• 한국대기환경학회지
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• 제23권1호
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• pp.132-140
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• 2007

Concentrations of atmospheric fine particles in Chungnam were measured at 7 sampling sites during 2005. The daily average concentrations of PM 10, PM2.5, and PM1 ranged from 14.9 to $136.5{\mu}g/m^3$, 8.2 to $113.2{\mu}g/m^3$, and 5.7 to $107.5{\mu}g/m^3$, respectively, and the highest levels were observed at Yeongi site. The lowest concentrations for the all size fractions of particulate were observed at Taean located at the west end of the peninsula. The daily average PM10 concentrations were below the current National Standard at all sites, while the daily average PM2.5 concentrations frequently exceeded the US Standard at Cheonan, Dangjin, Boryeong, and Yeongi sites. The frequencies of PM2.5 concentrations exceeding the US standard at Cheonan, Dangjin, Boryeong, and Yeongi were 10.8%, 6.7%, 6.7%, and 26.7%, respectively. In addition, $68{\sim}80%$ of PM10 was in the PM2.5 fraction indicating that fine particles were the major component of atmospheric particles in Chungnam.

• 한국환경과학회지
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• 제26권2호
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• pp.159-172
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• 2017

Asthma deaths in Seoul peaked on the third, fifth, and second days after the PM concentration exceeded the daily average concentration standard. We classified the synoptic meteorological conditions, based on the days involving such cases, into three categories. Type 1 included the meteorological condition likely to cause high air pollution concentrations in the leeward region, the dominant wind direction of which is the northwest. Type 2 included the meteorological condition likely to cause high air pollution concentrations due to the weak wind velocity under stable atmospheric conditions. Type 3 was when the passage low atmospheric pressure and the expansion of high atmospheric pressure occurred at the rear, indicating a meteorological condition likely to cause high air pollution, in certain regions. Type 1 occurred 11 times, with high concentrations of over $100{\mu}g/m^3$ being observed in the southeastern part of Seoul. Type 2 occurred 24 times, often accompanied by a PM concentration of $100{\sim}400{\mu}g/m^3$. Type 3 occurred 11 times, and was accompanied by several days of yellow dust that accounted for the highest concentrations.

• 분석과학
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• 제36권4호
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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.

• 대기
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• 제26권3호
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• pp.387-400
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• 2016

In this study, the atmospheric $CO_2$ concentrations estimated by CT2013B, a recent version of CarbonTracker, are compared with $CO_2$ measurements from the Comprehensive Observation Network for Trace gases by Airliner (CONTRAIL) project during 2010-2011. CarbonTracker is an inversion system that estimates surface $CO_2$ fluxes using atmospheric $CO_2$ concentrations. Overall, the model results represented the atmospheric $CO_2$ concentrations well with a slight overestimation compared to observations. In the case of horizontal distribution, variations in the model and observation difference were large in northern Eurasia because most of the model and data mismatch were located in the stratosphere where the model could not represent $CO_2$ variations well enough due to low model resolution at high altitude and existing phase shift from the troposphere. In addition, the model and observation difference became larger in boreal summer. Despite relatively large differences at high latitudes and in boreal summer, overall, the modeled $CO_2$ concentrations fitted well to observations. Vertical profiles of modeled and observed $CO_2$ concentrations showed that the model overestimates the observations at all altitudes, showing nearly constant differences, which implies that the surface $CO_2$ concentration is transported well vertically in the transport model. At Narita, overall differences were small, although the correlation between modeled and observed $CO_2$ concentrations decreased at higher altitude, showing relatively large differences above 225 hPa. The vertical profiles at Moscow and Delhi located on land and at Hawaii on the ocean showed that the model is less accurate on land than on the ocean due to various effects (e.g., biospheric effect) on land compared to the homogeneous ocean surface.

• 한국환경과학회지
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• 제19권7호
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• pp.861-869
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• 2010

The present study aims to evaluate the characteristics of atmospheric polycyclic aromatic hydrocarbons (PAHs) pollution in roadside and residential areas of two Korean metropolitan cities (Seoul and Incheon) and a background area (Seokmolee). This purpose was established by analyzing temporal and spacial concentration distribution of total and 7 individual PAHs, which were extracted from ambient particulate matters, and by utilizing a multivariate statistical method (principal component analysis, PCA) for the qualitative determination of potential PAH sources. Target PAHs included benzo(a)anthracene (BaA), benzo(a)pyrene (BaP), benzo(b)fluoranthene (BbF), benzo(k)fluoranthene (BkF), chrysene (Chr), dibenzo(a,h)anthracene (DahA), and indeno(1,2,3-cd)pyrene (IcdP). For all surveyed sites, the concentrations of total PAHs were higher in winter season than in other seasons. However, the concentrations of individual PAHs varied with surveyed sites. In both residential and roadside sites of Seoul and Incheon, BbF revealed the highest atmospheric levels. For all 7 target PAHs, the ambient concentrations were higher in Seoul and Incheon than in a background area (Seokmolee). In both residential and roadside areas, the concentrations of 4 target PAHs (BaA, BbF, BkF, DahA) were higher in Incheon than in Seoul. However, both the residential and roadside Chr concentrations were comparable in Seoul and Incheon. In addition, the residential IcdP concentrations were higher in Incheon than in Seoul, whereas the roadside concentrations were higher in Seoul. The roadside and residential BaP concentrations exhibited the reverse result to the IcdP concentrations. An PCA analysis suggested that atmospheric PAHs in both residential and roadside areas would be due to combined effects of several potential sources such as gasoline- and diesel-fueled vehicles, coal/oil combustion, and waste incineration.

• 한국대기환경학회지
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• 제34권5호
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• pp.677-686
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• 2018

An intensive measurement was conducted to study the mass and number concentrations of atmospheric aerosols in Anheung ($36.679^{\circ}N$, $126.186^{\circ}E$), the west coastal measurement site of Korea during December 2017~April 2018. To evaluate relationships between the aerosols and meteorological parameters, comparisons of Optical Particle Counter (OPC) measured data and Auto Weather System (AWS) data were performed. Measured PM mass concentrations are $PM_{10}=42.814{\pm}30.103{\mu}g/m^3$, $PM_{2.5}=29.674{\pm}25.063{\mu}g/m^3$, $PM_1=28.958{\pm}24.658{\mu}g/m^3$, respectively. The PM ratios showed that the $PM_{10}$ concentrations contained about 67.8% of $PM_{2.5}$, while most part of $PM_{2.5}$ was $PM_1$ (about 97.1%). Timely collocation with AWS data were performed, exploring relations with the PM concentrations. PM concentrations can be explained by wind direction and relative humidity conditions. The significant reductions of fine particles in mass and number concentrations may attribute to actions on particle growth and wet removal. In these results, we suppose that the aerosol concentrations and size distributions are affected by inflow direction and air mass sources from the origin.

• 한국대기환경학회지
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• 제3권2호
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• pp.11-17
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• 1987

Atmospheric particulate matter (A.P.M.) was collected on quartz fiber filters from March 1985 to February 1986 at Chung-Ang University according to particle size using Andersen high-volume air smapler, and benzo (a) pyrene concentration in these particulates were analyzed by high performance liquid chromatography. The annual arithmetic mean concentration of A.P.M. was 115.50$\mug/m^3$. The annual arithmetic mean concentrations of coarse particles and fine particles in A.P.M. were 52.54$\mum/m^3$ and 62.96$\mum/m^3$ respectively. THe annual arithmetic mean concentration of benzo(a)pyrene in A.P.M. was 1.44$ng/m^3$. THe annual arithmetic mean concentrations of benzo(a)pyrene in coarse particles and fine particles were 0.05 $ng/m^3$ and 1.39 $ng/m^3$ respectively. Thus, the concentration of benzo(a)pyrene showed maldistribution of 96.53% in fine particle. A.P.M. showed wide fluctuation according to the season. The concentration of A.P.M. was lowest in summer and high in spring and winter. Coarse and fine particle concentrations in A.P.M. were highest in spring and winter, respectively. The concentrations of benzo(a)pyrene was highest in winter and lowest in summer. The concentrations of benzo(a)pyrene in fine and coarse particles were highest in winter and spring, respectively.

• 한국환경과학회지
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• 제11권8호
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• pp.801-810
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• 2002

The current paper describes the indoor/outdoor air quality in school environments through analyses of the heavy metal concentrations using Inductive Coupled Plasma(ICP). School environments in a heavy traffic area, two industrial areas, quasi-industrial area, and residential area were evaluated. The results were as follows: (1) The locations with the highest indoor and outdoor concentrations of heavy metals were the industrial areas followed by the heavy traffic area, residential area, and quasi-industrial area in a descending order of magnitude. Plus, the indoor heavy metal concentrations were higher then the outdoor ones. (2) The main heavy metal components were Zn, Al and Ca. Higher concentration levels were found indoors than outdoors. The heavy metal concentrations were also higher in the classrooms than in the corridor or outdoors. (3) The total heavy metal concentrations in the studied areas were highly dependent on the weather elements. including the relative humidity, mixing ratio, and wet-bulb depression. Accordingly, special ventilation systems are recommended to reduce air pollution in school environments.