• Journal of Environmental Science International
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• v.11 no.12
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• pp.1235-1242
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• 2002

The purpose of this study is to estimate wet deposition flux and to investigate wet deposition characteristics by using the ADOM model. Wet deposition flux of highly reactive $SO_2$ is estimated by applying observed meteorological parameters and concentrations of chemical species to the ADOM model. Wet deposition is largely dependent on large scale precipitation and cloud thickness. Wet deposition flux of sulfate depends on $SO_2$ oxidation in clouds. When large amount of $SO_2$ is converted to sulfate, deposition flux of sulfate increases, but wet deposition flux of $SO_2$ is small. On the whole, the pattern of sulfate wet deposition flux agrees with the typical pattern of sulfate wet deposition that is high in the summer(July) and low in the winter(January).

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.3
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• pp.231-241
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• 1997

A tracer model was applied in the Far East Asia to investigate the dry deposition rates of air pollutants on Korean Peninsula originated from different countries including China and Japan. Wind direction was chosen to predict the maximum deposition rates and SO$_2$ was chosen as a tracer to estimate the source strength. Model simulation shows that inflow, deposition and airborne ratios of China-originated SO$_2$ were 50%, 8% and 30%, respectively, at most. Also it was found that deposition, outbounded and airborne ratios of Korea-originated SO$_2$ were 15~77%, 8~75%, and 3~30%, respectively Model simulation also shows that inflow, deposition and airborne ratios of Kyushu-originated SO$_2$ were, 30~45%, 8~14％ and 20~25%, respectively. This study shows that tracer model can be applied on the estimation of air pollutants partitioning in regional scale and that more sophisticated modules and schemes can be developed and applied to better predict the transboundary amounts of air pollutants in this region.

• Journal of Environmental Science International
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• v.10 no.1
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• pp.1-8
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• 2001

This study was carried out estimating the dry deposition flux of $SO_2$at eight urban areas in Korea during one year of 1996. To calculate the deposition flux, deposition velocities were calculated by turbulence parameters estimated from routine meteorological data. Also, hourly averaged $SO_2$concentrations which calculated from air pollution monitoring data of each city were used. The dry deposition velocities were mostly higher in the coastal areas than the other areas, which would be caused by relatively strong wind. And, they were high in the daytime because of turbulence activities. The deposition flux of $SO_2$is mainly related to the atmospheric concentration. The annual average $SO_2$concentration and the deposition flux were 22.62ppb and 1510.52g/$\textrm{km}^2$/hr at Pusan respectively. Also, the flux was higher in winter than other season, which was a significant contribution of exhausted fuel for heating. While the deposition velocity was high to 0.688cm/sec at Yosu in case of strong wind and small cloud cover, the deposition flux was high to 1597.4g/$\textrm{km}^2$/hr at Pusan in case of weak wind and small cloud cover.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.5
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• pp.465-478
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• 1998

In this study, seasonal variations of the dry deposition velocity and deposition flux for the sulfur dioxide were analysed. The field observation was performed during one year (from November 1, 1995 to October 31, 1996) in Chunchon basin. The turbulence data were measured by 3-dimensional sonic anemometer/thermometer, and were estimated by mean meteorological data obtained at two heights (2.5 m and 10 m) of meteorological tower. Also, the estimation methods were evaluated by comparing the turbulence data. The results showed that the estimated dry deposition velocity and turbulence parameter such as uc and sensible heat flux using mean meteorological data were relatively similar to the sonic measurements, but all showed somewhat large differences. The dry deposition velocity was large in summer and small in winter mainly due to canopy resistance (rc). The major factor which affects diurnal variation of the velocity was aerodynamic resistance (rw). The SO2 dry deposition flux was large in winter and small in summer in Chunchon.

• Analytical Science and Technology
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• v.9 no.1
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• pp.98-106
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• 1996

The concentration of sulfur dioxide in Wonju City was predicted using TCM (Texas Climatological Model). We have studied the transportation and wet deposition of $SO_2$ using the TCM and the analysis of rainfalls. The results are as follows : At the Hak-Sung Dong site in Wonju city, the correlation coefficient between the measured and calculated concentrations were 0.904. Sulfur dioxide was washed out by wet deposition. The wet deposition ratio to total amount of emitted sulfur dioxide was higher in summer than in autumn and winter seasons due to heavy rainfall in summer. The correlation coefficient between the precipitation and wet deposition of sulfur dioxide was 0.68. The months with greater rainfall showed that the measured concentrations of sulfur dioxide were much lower than the predicted ones. Although the amount of precipitation in April was smaller than in summer, the wet deposition ratio in April was much higher than any other months, due to the sulfur dioxide that was adsorbed on particulate matter and moisture was transported during the period of yellow sand phenomena from China.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.1
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• pp.31-42
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• 2000

The dry deposition velocities and fluxes of air pollutants such as SO2(g), O3(g), HNO3(g), sub-micron particulates, NO3(s), and SO42-(s) were estimated according to local meteorological elements in the atmospheric boundary layer. The model used for these calculations was the multiple layer resistance model developed by Hicks et al.1). The meteorological data were recorded on an hourly basis from July, 1990 to June, 1991 at the Austin Cary forest site, near Gainesville FL. Weekly integrated samples of ambient dry deposition species were collected at the site using triple-fiter packs. For the study period, the annual average dry deposition velocities at this site were estimated as 0.87$\pm$0.07 cm/s for SO2(g), 0.65$\pm$0.11 cm/s for O3(g), 1.20$\pm$0.14cm/s for HNO3(g), 0.0045$\pm$0.0006 cm/s for sub-micron particulates, and 0.089$\pm$0.014 cm/s for NO3-(s) and SO42-(s). The trends observed in the daily mean deposition velocities were largely seasonal, indicated by larger deposition velocities for the summer season and smaller deposition velocities for the winter season. The monthly and weekly averaged values for the deposition velocities did not show large differences over the year yet did show a tendency of increased deposition velocities in the summer and decreased values in the winter. The annual mean concentrations of the air pollutants obtained by the triple filter pack every 7 days were 3.63$\pm$1.92 $\mu\textrm{g}$/m3 for SO42-, 2.00$\pm$1.22 $\mu\textrm{g}$/m-3 for SO2, 1.30$\pm$0.59 $\mu\textrm{g}$/m-3 for HNO3, and 0.704$\pm$0.419 $\mu\textrm{g}$/m3 for NO3-, respectively. The air pollutant with the largest deposition flux was SO2 followed by HNO3, SO42-(S), and NO3-(S) in order of their magnitude. The sulfur dioxide and NO3- deposition fluxes were higher in the winter than in the summer, and the nitric acid and sulfate deposition fluxes were high during the spring and summer.

• Journal of Environmental Health Sciences
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• v.22 no.2
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• pp.124-129
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• 1996

In order to investigate the deposition chara.cteristics of water-soluble ionic components in dustfall in Kwangju city, dustfall samples were collected by deposit jar for one year from December 1992 to November 1993. The depositjon amount of dustfall and water-soluble ionic components ($SO_4^{2-}, NO_3^-, Cl^-, NH_4^+, Na^+, Ca^{2+}, Mg^{2+}, K^+$) were measured. The total deposition amount of dustfall was 10.0 ton/$km^2$/month and showed seasonal trend of Summer and Spring > Fall and Winter. The total deposition amounts of water-soluble components showed 2.41 ton/$km^2$/month and seasonal trend of Summer > Fall > Spring > Winter. Deposition amount of $SO_4^{2-}$ was 0.99 ton/$km^2$/month which makes up 41% of water-soluble components. The deposition amounts of dustfall and watersoluble components according to the sampling points were approximately similar to each other. From this result, it can be estimated that the deposition amounts of dustfall and water-soluble components in dustfall were more influenced by the seasonal variation than the regional emission characteristics of pollution source. The content of each ionic component to the deposition amount of water-soluble components showed in order of $SO_4^{2-} > Cl^- > NH_4^+ > Na^+ > Ca^{2+} = K^+ > NO_3^- > Mg^{2+}$ respectively.

• Journal of Environmental Health Sciences
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• v.32 no.4 s.91
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• pp.359-372
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• 2006

In order to investigate the daily deposition characteristics of water-soluble inorganic components in airborne deposit on the Iksan, deposition samples were collected using a deposition gauge from October 16 to November 1, 2004. Deposition samples were collected using two different sampling gauges, a dry gauge and a wet gauge, respectively. To get wet the bottom of wet gauge during the sampling period, the volume of $30{\sim}50ml$ distilled ionized water was added in a wet gauge before the beginning of each deposition sampling. Deposition samples were collected twice a day and analyzed for inorganic water-soluble anions ($Cl^-,\;{NO_3}^-,\;{SO_4}^{2-}$) and cations (${NH_4}^+,\;Na^+,\;K^+,\;Mg^{2+},\;Ca^{2+}$) using ion chromatography. Qualify control and quality assurance of analytical data were checked by the data obtained from reinjection of standard solution, Dionex cross check standard solutions, and random several deposition samples, and measured data was estimated to be reliable. Considering the deposition sample volume, the sampling time, the surface area of sampling container, and the ion concentration measured, the daily deposition amounts for measured ions were calculated in $mg/m^2$. The total daily deposition amounts of all measured ions for dry and wet gauge were $7.5{\pm}2.8$ and $17.7{\pm}4.2mg/m^2$, respectively. A significant increase in deposition amount during rainfall days was observed for both wet gauge and dry gauge, having no difference of deposition amount between in wet gauge and in dry gauge. The mean deposition of all ions measured in this study were higher in wet gauge than in dry gauge because of the surface difference of the sampling container, especially for ${NH_4}^+\;and\;{SO_4}^{2-}$. The mean deposition amounts of ${NH_4}^+\;and\;{SO_4}^{2-}$ in wet gauge were found to be about 10 times and 3 times higher than those in dry gauge, while the rest of the chemical species were equal or a little higher in wet gauge than in dry gauge. Dominant species in dry gauge were ${NO_3}^-\;and\;Ca^{2+}$, accounting for 21% and 28% of the total ion deposition, whereas those in wet gauge were ${SO_4}^{2-}\;and\;{NH_4}^+$, accounting for 19% and 41% of the total ion deposition, respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.1
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• pp.73-81
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• 2005

It is widely accepted that, at present, the SO$_2$ emissions in China are not increasing thanks to the rigorous Chinese government policies. However, with the development of western China, it is possible that the SO$_2$ emission amounts might increase in regional scale. In this study, changes of sulfur deposition pattern and unprotected ecosystem in east Asia due to the sulfur emission pattern changes in China are studied by using the RAINS-Asia model. Five scenarios have been postulated to understand the effects on east Asia, especially, on Korea and Japan. It is found that the increase of SO$_2$ emission in western China might increase the total emission in whole China. And the amount of sulfur deposition from western China on east Asia would be higher than those from eastern China. The deposition amount of sulfur species on Asia is 3.2 Mt when SO$_2$ are emitted from western China only while 2.6 Mt from eastern China only. Generally, Korea and Japan are influenced more by emissions from eastern China than western China. However, if the SO$_2$ emissions from western China increase by 100% while those decrease by 10% in eastern China compared to the base case, the deposition amount of sulfur species on Korea and Japan would be higher than the base case. The fraction of unprotected ecosystem in Korea and Japan for the base case are 50 and 5%. However, if the emissions from western China increase by 100% while those decrease by 10% in eastern China, the fraction of unprotected ecosystem in Korea and Japan would be 52 and 6%.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.4
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• pp.477-486
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• 2006

Dry deposition fluxes for $SO_2$, particulate sulfate, nitrate, ammonium and $HNO_3$ were estimated in urban area for the time period January$\sim$ October 2005. Fluxes were generated using atmospheric concentration data collected both in Acid Deposition and Air Quality Monitoring Networks, and deposition velocities computed by combining land-use data with meteorological information. The resulting annually averaged $SO_2$, $NO_3$, and aerosol deposition velocities were found to be 0.4 cm/s, 4.3 cm/s and 0.1 cm/s, respectively, and thus deposition rates were 4.4 mg/$m^2$. day for $SO_2$, and 5.4 mg/$m^2$ . day for $NHO_3$, and particulate sulfate, ammonium and nitrate recorded 1.0 mg/$m^2$ . day, 0.4 mg/$m^2$ . day and 0.4 mg/$m^2$ day, respectively. Maximum for in seasonal variation of monthly averaged deposition velocities occurred in summer in contrast to $HNO_3$ showing peak in spring. There was no significant variation for aerosol. The dry to total (wet and dry) deposition contributed about 40% for sulfur and 28% for nitrogen species in this study.