• Journal of Environmental Health Sciences
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• v.22 no.4
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• pp.62-68
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• 1996

Precipitation samples were collected by the wet-only event sampling method at Seoul from September 1991 to April 1995. Concentrations of samples for the ion components($NO_3^-, NO_2^-, SO_4^{2-}, Cl^-, F^-, Na^+, K^+, Ca^{2+}, Mg^{2+}$ and $NH_4^+$) were measured in addition to pH and electric conductivity. During the sampling period, 182 samples were collected, but only 163 samples were identified as valid. The pH, calculated from the volume-weighted $H^+$ concentration, was found to be 4.7, indicating a relatively intensive acidity compared with data from other regions of the world, where acid deposition was known to be a problem. Above all, the concentration of non-seasalt sulfate was $84 \mu eq/L$, which was the highest compared to that measured in other regions of the world. The major acidifying ions in the precipitation at Seoul were identified as sulfate and nitrate except for chloride, because the Cl/Na ratio in the precipitation was close to the ratio in seawater. If all of the non-seasalt sulfate and nitrate existed in the form of sulfuric and nitric acids, respectively, the average pH in the precipitation was calculated as 3.7, lower than the measured value. Consequently, the difference between the calculated and measured pH suggest that the acidity of precipitation was neutralized by alkaline species, not due to the low contribution of an anthropogenic air pollutants to the precipitation. The equivalent concentration ratio of sulfate to nitrate was 3.5, which indicated that the contributions of sulfuric and nitric acids to the precipitation acidity were 78% and 22%, respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.4
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• pp.385-392
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• 1999

This study was carried out to investigate the constituents of inorganic ions of precipitation in Mokpo and Yeochon area from Jan. 1996 to Dec. 1997. The volume-weighted mean pH of precipitation was 5.7(4.8~7.8) at Mokpo, and 5.6(5.1~7.4) at Yeochon area, respectively. The non-seasalt(nss) anion concentrations were found in order of $nss-SO^{2-}_4>NO^-_3>nss-Cl^-$ at two areas. The portion of $nss-SO^{2-}_4;and;NO^-_3$ was 71~84% out of anions. The the non-seasalt cation concentrations were found in order of $NH^+_4>nss-Ca^{2-}>nss-Mg^{2+}>nss-K^-$ at two areas. The portion of $NH^+_4;and; nss-Ca^{2+}$ was 85~92% out cations. Compared regionally the year concentraton of $nss-SO^{2-}_4$, the result of Yeochon was 3 times higher than that of Mokpo in 1996, while the results of two regions were almost similar in 1997. The reason was that Yeochon was restricted area of the use of 0.5% sulfur B-C oil, controlled air pollution emission area, controlled semitotal amounts of air pollution emission area and partial operating of factories in 1997. There were no ions having high correlation with $H^+,;but;nss-SO^{2-}_4,;NO^-_3,;NH^+_4;and;nss-Ca^{2+}$ showed high correlation coefficient each other. It seems that these ions have little correlation with $H^+$ because they are washed out on binding state. Factor analysis showed that the first factor was complicated factor containing anthropogenic and soil resource, the second factor was sea-salt resource and the third factor was independent behavior of hydrogen at Mokpo. While, the first factor was complicated factor containing anthropogenic and sea-salt resource, the second factor was $Ca(NO_3)_2$ salt and the third factor was $NH^+_4;and;SO^{2-}_4$ synergied by resource and combination at Yeochon.

• Journal of Environmental Health Sciences
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• v.24 no.3
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• pp.77-86
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• 1998

The concentrations of atmospheric dimethylsulfide (DMS) and the relevant environmental parameters were measured as part of the 3rd year project (August 1997-July 1998) to investigate the long range transport of atmospheric pollutants (LRTAP) between China and Korea. The main purpose of this study was to derive the contribution of natural sulfur emissions (represented by oceanic DMS fluxes) in estimating the total budgets of sulfur transported across the Yellow Sea. To this end, DMS concentrations were determined from the two western coastal monitoring sites (Cheju and Kang Hwa islands) during three field intensive experiments covering fall, winter, and spring seasons. From these series of experiments, we found that DMS concentrations of Cheju and Kang Iffwa were averaged at 74 $\pm$ 49.5 (range: 19~282 pptv (N=81)) and 63.7 $\pm$ 35.1 (range:25.8~131 pptv (N=19)), respectively. By combining these 3rd year data with those measured previously from the 2nd year, we were able to derive some general pictures of seasonal distribution patterns of DMS. Although DMS data were difficult to derive relationships with other parameters determined simultaneously, they were rarely exhibiting good correlations with temperature or wind speed. The oceanic flux of DMS for the western coastal regions of Korea, when estimated based on our data from two islands, was found on the range of 8.8~12.2 GgS/yr. By considering the relationship between DMS and non-seasalt sulfate, we could also provide rough estimate of relative significance of natural emissions of sulfur. If oceanic DMS emitted from those regions is entirely converted to sulfate, it could represent 10 to 25% of total sulfur budgets in the western Sea of Korea.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.1
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• pp.9-18
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• 1997

Precipitation samples were collected by the wet- only event sampling method from Seoul during September 1991 to April 1995. These samples were analyzed for the concentrations of the major ionic components (N $O_3$$^{[-10]}$ , N $O_2$$^{[-10]}$ , S $O_4$$^{2-}$, C $l^{[-10]}$ , $F^{[-10]}$ , N $a^{＋}$, $K^{+}$, $Ca^{2＋}$, $Mg^{2＋}$, and N $H_4$$^{＋}$), pH, and electric conductivity. During the study period, a total of 182 samples were collected, but only 163 samples were used for the data analysis via quality assurance of precipitation chemistry data. The volume-weighted pH was found to be 4.7. The major acidifying species from our precipitation studies were identified to be non-seasalt sulfate (84$\pm$9 $\mu$eq/L) and nitrate (24$\pm$2 $\mu$eq/L) except for chloride. Because the Cl/Na ratio in the precipitation was close to the ratio in seawater. If all of the non-seasalt sulfate and nitrate were in the form of sulfuric and nitric acids, the mean pH in the precipitation could have been as low as 3.7 lower than the computed value. Consequently, the difference between two pH values indicate that the acidity of precipitation was neutralized by alkaline species. The equivalent concentration ratio of sulfate to nitrate was 3.5, indicating that sulfuric and nitric acids can comprise 78％ and 22％ of the precipitation acidity, respectively. Analysis of temporal trend in the measured acidity and ionic components were also performed using the linear regression method. The precipitation acidity generally showed a significantly decreasing trend, which was compatible with the pattern of the ratio (N $H_4$$^{＋}$＋C $a^{2＋}$)/ (nss-S $O_4$$^{2-}$＋N $O_3$$^{[-10]}$ ).).

• Journal of Korean Society for Atmospheric Environment
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• v.8 no.3
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• pp.191-197
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• 1992

In order to investigate the chemical components of acid precipitation at Kangwha near the Yellow Sea and Seoul in Korea, the precipitation samples were collected by wetonly precipitation sampler from February 1991 to January 1992, and pH, electric conductivity(E. C.) and major water-soluble ionic components were analyzed. Strong negative linear correlations were observed between the rainfall amount and the sum of major ionic components in $\mu eq/\ell$ at two sites. The sum of major ionic components also correlated negatively with rain intensity. The analytical results of precipitation samples at two sites were compared each other. Average values of volume-weighted pH were found to be 5.21 at Kangwha and 5.09 at Seoul. The cationic abundance($\mu eq/\ell$) in rainwater showed the general trend $NH_4^+ > Na^+ > Ca^{2+} > Mg^{2-+} > H^+ > K^+$ at Kangwah and $NH_4^+ > Ca^{2+} > Na^+ > H^+ > Mg^{2+} > K^+$ at Seoul. The anionic abundance showed the general trend $SO_4^{2-} > Cl^- > NO_3^-$ at Kangwha and $SO_4^{2-} > NO_3^- > Cl^-$ at Seoul. The concentrations of seasalt such as $Na^+ and Cl^-$ were higher at Kangwha than Seoul. The concentrations of $nss-SO_4^{2-}, nss-Cl^- and NO_3^-$ which are acid composition were higher at Seoul(96.3 $\mu eq/\ell$) than Kangwha(69.0 $\mu eq/\ell$). The contribution of seasalt to the composition of precipitation were higher at Kangwha(34.1%) than Seoul(15.7%). Ammonia and calcium species in rainwater at Kangwha and Seoul are interpreted to have 91% of neutralizing capacity of the original sulfuric and nitric acids. Provided that the precipitation acidity originates primarily from sulfate and nitrate, sulfate was found to contribute about 73-75% of the free precipitation acidity.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.2
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• pp.143-152
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• 1998

The aerosol concentrations of ionic components were measured on a daily basis from a coastal monitoring site located at Kosan, Cheju Island from 26 September to 5 October 1997 as a field-intensive for a LRTAP project The chemical species we investigated include most of important inorganic species (i.e., Cl-, NO3-, F-, SO42-, Na+, NH4+, and K+) and some organic species (i.e. formats, acetate, and methanesulfonate (MSA) ions). The concentration data of those important inorganic and organic species obtained during this study were evaluated to properly address their chemical and physical characteristics. Most of major inorganic components including sulfate, sodium, chloride, and potassium ions exhibited very conservative relationships with each other such that the concentration ratios of any pair are quite analogous to that of seawater ratio. Since the oceans serve as the major sources of ionic constituents, their concentration changes appear to be senstively reflected by the factors affecting air-sea processes such as an increase in wind speed or changes in wind direction. A comparative analysis of sulfur-containing species such as seasalt (SS) and nonseasalt (NSS) sulfate and MSA were also made to assess the factors influencing the S cycling. An evaluation of NSS/SS ratios suggests that most of sulfate be associated with NSS fraction rather than 55 one. The finding of lower MSA/NSS-SO42- ratio along with a line of physical evidence such as intrusion of anthropogenically affected air mass suggests that the oxidation of S species have been promoted under the conditions encountered during the study period. Finally, the concentration data of carboxylic species (such as formats and acetate ions) were also analyzed. Although the existence of temporal trends were difficult to assess, these data indicate that their contribution to the precipitation acidity may not be significant enough.

• Journal of Environmental Science International
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• v.7 no.5
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• pp.707-716
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• 1998

The chemical characteristics of precipitation was investigated in Pusan area. Samples were collected from January to November in 1996 at 4 sites, and analyzed pH, major soluble ionic components(C $l^{[-10]}$ , N $O_3$$^{[-10]}$ , S $O_4$$^{2-}$, N $a^{+}$, $K^{+}$, N $H_4$$^{+}$, $Mg^{2+}$, $Ca^{2+}$). The order of anion and cation concentrations for the initial precipitation were C $l^{[-10]}$ ＞ S $O_4$$^{2-}$ ＞ N $O_3$$^{[-10]}$ , and $Ca^{2+}$ ＞ N $a^{+}$ ＞ N $H_4$$^{+}$ ＞ $Mg^{2+}$ ＞ $K^{+}$, respectively. At coastal sites(P1 and P2) C $l^{[-10]}$ and N $a^{+}$ of maritime sources (seasalt) were high, but at inland sites(P3 and P4) nss-C $a^{2+}$ and nss-S $O_4$$^{2-}$ were high. Calcium ion for the initial precipitation showed high value of enrichement factor(EF) relative to seawater composition. The contribution of seasalt to the composition of precipitation was higher at bite P1 (53.5%) than those of the other sites. Throughout the year the concentrations of major ions for the initial precipitation were low in the heavy rain season. The mean pH for the initial precipitation was 5.4 and showed the negative relationship with the precipitaion amount. The S $O_4$$^{2-}$ and N $O_3$$^{[-10]}$ do not play an important role in rain acidification due to the high(97%) neutralizing effect of amonia and calcium species.and calcium species.

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.2
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• pp.98-104
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• 1994

Precipitation samples were collected at Kosan, Cheju Island over a period of 6 months An automatic rain sampler was manufactured domestically and installed at Kosan station. All samples were collected on a weekly basis. Samples were analyzed for S $O_4$$^{=}$, N $O_3$$^{[-10]}$ , C $l^{[-10]}$ , N $H_4$$^{+}$, N $a^{+}$, $K^{+}$, $Ca^{++}$, $Mg^{++}$, and pH and specific conductivity. The quality analysis of rain sample data were performed based on ion balance and specific conductivity. The pH of rain samples ranged between 4.6 to 6.6. Bicarbonate ion concentration were included in ion balance and specific conductivity calculations. The sum of cation concentrations were slightly greater than the sum of anion concentrations. Calculated specific conductivity was greater than measured specific conductivity. The most probable explanations for this discrepancy is "an anion too low or anion missing." Two criteria were used to identify outliners. They are 1) the difference between the sum of anion concentrations and cation concentration is more than 50 $\mu$eq./1 and 2) the difference between calculated and measured specific conductivity is more than 25%. Chemical analysis from several samples did not satisfy these quality control criteria. Volume weighted average concentrations were calculated. Dominant free acids in rain samples were N $a^{+}$, C $l^{[-10]}$ , S $O_4$$^{=}$, N $O_3$$^{[-10]}$ ions in order of abundance. Non-seasalt sulfate comprises 76% of total sulfate.sulfate.e.ate.e.

• Journal of Environmental Health Sciences
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• v.26 no.2
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• pp.41-48
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• 2000

This study has been carried out to determine the seasonal characteristics of concentration of various ionic (CI-, NO3-, SO42-, Na+, NH+, K+, Ca2+) and heavy metallic (Pb, Mn, Cu, Ni) species in Pusan from August 1997 to April 1998. The concentrations of CI-, Na+, K+ were higher during summer with 2.98 ${\mu}{\textrm}{m}$/㎥. Seasonal variation of total concentration of but the concentration of NH4+ was higher during winter with 2.46${\mu}{\textrm}{m}$/㎥. Seasonal variation of total concentration of heavy metals(Pb, Cu, Mn, Ni) were 186.0 ng/㎥ in summer, 222.6 ng/㎥ in autumn, and 135.83 ng/㎥ in winter. Over the seasons inspected, the concentration of Mn was higher in coarse particles than fine particles and concentration of Ni was higher in fine particles than coarse particles. during yellow sand period, the concentration of TSP was increased about two times than that of other period. SO42-, Ca2+ concentrations were higher than other ionic components because of soil particles. The concentration of Ni showed 94.62ng/㎥ was increased about 4~5 times than other period. Principal component of the yellow sand, SO42-, Ca2+ could be discreased by rainfall and washout effect of atmospheric aerosol was higher in coarse particles than fine particles. Results from PCA(principal component analysis) showed that major pollutant was NaCl by seasalt particulate and (NH4)2SO4.

• Journal of Environmental Health Sciences
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• v.20 no.4
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• pp.1-9
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• 1994

In order to investigate the regional level of air pollutants at Kangwha island situated on the western coast in Korea, the suspended particulate matter samples were collected by using the low volume air sampler on ten interval from March 1992 to February 1993 and the mass concentration of suspended particulate matter (SPM) and the chemical composition of water-soluble major ionic components in SPM samples were measured. During the sampling period, the average concentration of SPM under diameter 10 $\mu$m was found to be 48 $\mu$g/m$^3$ (+ 12). The seasonal concentration of SPM was showed in order of spring>fall>winter>summer. It was considered that higher concentration on spring than other season was affected by the long-range transport of Yellow sand particulate from China continent and lower concentration on summer by the washout and rainout effect of large rainfall. The content of water-soluble component in SPM samples was founded to be about 31% (14.69 $\mu$g/m$^3$) and 65% was unknown or unanalyzed. The content of cationic component showed in order of NH$_4^+$ (44.6%)>Na$^+$ (21.2%)>K$^+$ (14.7%)>Ca$^{2+}$ (13.6%)>Mg$^{2+}$ (5.9 %) and the content of anionic component SO$_4^{2-}$ (62.5%)>NO$_3^-$ (22.3%)>Cl$^-$ (15.2%), respectively. This fact indicates that ammonium and sulfate ion of water-soluble component in SPM sample were dominant in this region. From the chemical composition of water-soluble component, the most of Na$^+$, Mg$^{2+}$ and Cl$^-$ were originated from seawater source but K$^+$, Ca$^{2+}$ and SO$_4^{2-}$ were originated from other non-marine source. The contribution of seasalt to the composition of precipitation was 23%.