Gosan Site Research Articles

Pollution Characteristics of Ambient Fine Particulate Matters at Mt. Halla-1100 and Gosan Sites in Jeju Island

Ambient fine particulate matters of PM10 and PM2.5 were collected at the Mt. Halla-1100 site (a site at an altitude of 1100 meters on Mt. Halla) and the Gosan site, which comprise a typical mountainous site and coastal background site, respectively, on Jeju Island. The major water-soluble ionic species of these sites were analyzed. The average mass concentrations of PM10 and PM2.5 at the Mt. Halla-1100 site were 0.59 times lower and 0.78 times lower, respectively, than those at the Gosan site. The composition ratios of the major secondary air pollutants (nss-SO42-, NO3-, and NH4+) of PM10 and PM2.5 were 86.2% and 93.2%, respectively, at the Mt. Halla-1100 site, while those at the Gosan site were 67.7% and 87.2%, respectively. These results show the comparatively larger contributions at the Mt. Halla-1100 site. The principal component analysis reveals that the main affecting factors for the ionic compositions of PM10 and PM2.5 particles at both sites are the anthropogenic emission sources, especially the comparative influence of organic acids at the Mt. Halla-1100 site, and the marine sources at the Gosan site. Based on the neutralization factors, the fine particulate matters were acidified mainly by sulfuric and nitric acids, and the neutralization was relatively caused by calcium carbonate in PM10 particles and ammonia in PM2.5 particles. The clustered back trajectory analyses indicated that the major ionic concentrations of PM10 and PM2.5 comparatively increased when the airflow moved from continental China and the Korean Peninsula. The polluting influence from China was apparent in the upper planetary boundary layer (PBL) compared with that at ground level. Key Words: PM10, PM2.5, Mt. Halla-1100 site, Gosan site, Planetary Boundary Layer (PBL)

Ionic Compositions of PM10 and PM2.5 Related to Meteorological Conditions at the Gosan Site, Jeju Island from 2013 to 2015

Ionic Compositions of PM10 and PM2.5 Related to Meteorological Conditions at the Gosan Site, Jeju Island from 2013 to 2015

제주도 고산지역의 대기 라돈 배경농도 및 시계열 변동

제주도 고산지역의 대기 라돈 배경농도 및 시계열 변동

2013년 고산지역 연무, 황사, 연무-황사혼재 대기 에어로졸의 화학조성 특성

2013년 고산지역 연무, 황사, 연무-황사혼재 대기 에어로졸의 화학조성 특성

Influences of Long‐Range Transported Air Pollutants on Atmospheric TSP Aerosol Compositions at Jeju Island of Korea during 2011–2013

Atmospheric total suspended particulate aerosols were collected at the Gosan site of Jeju Island during 2011–2013, and their major water‐soluble ionic and elemental species were analyzed in order to examine the chemical composition change and pollution characteristics change between Asian dust (AD) and non‐Asian dust (NAD) periods. The comparison of the aerosol compositions showed that the concentrations of soil‐originated species such as nss‐Ca2+, Al, Fe, Ti, Mn, Ba, and Sr increased by as much as 4.5–18.6 times during the AD periods. Meanwhile, the concentrations of nss‐SO4 2 − and NO3 −, typical secondary aerosol species, increased 1.2 and 2.5 times, respectively. On the contrary, NH4 + concentration decreased slightly during the AD periods, probably because of the neutralization reaction of acidic ammonium ion with basic calcium carbonate. A comparison of ion balances suggested that the carbonate contents in AD are likely much larger than those of NAD. Based on a cluster back‐trajectory analysis, it was found that the concentrations of anthropogenic and soil‐sourced components, such as nss‐SO4 2 −, NO3 −, NH4 +, and nss‐Ca2+, increased when an air mass moved into Jeju Island from the China continent, but decreased when an air mass moved from the North Pacific Ocean.

황사, 연무, 박무 현상이 미세먼지 화학조성에 미치는 영향: 2014년 제주도 고산지역 측정

In order to examine the variation characteristics of chemical compositions in accordance with the different meteorological conditions, PM10 and PM2.5 were collected at Gosan site of Jeju Island in 2014, and then their ionic and elemental species were analyzed. The concentrations of nss-SO4 and NH4 were respectively 4.3 and 3.3 times higher in fine particle mode (PM2.5) compared to coarse particle mode (PM10-2.5), however NO3concentration was 1.6 times higher in coarse mode compared to fine particle mode. During Asian dust days, the concentrations of nssCa and NO3increased highly as 7.7 and 4.5 times in coarse particle mode, and 3.0 and 4.9 times higher in fine particles, respectively. Especially, the concentrations of the crustal species (Al, Fe, Ca, K, Mn, Ba, Sr, etc.) indicated a noticeable increase during the Asian dust days. For the haze days, the concentrations of secondary pollutants increased 2.2~2.7 and 2.9~6.0 times in coarse and fine particles, respectively, and they were 0.8~1.1 and 1.8~2.4 times, respectively, during the mist days. The aerosols were acidified largely by sulfuric and nitric acids, and neutralized mainly by ammonia in fine particle mode during the haze days, but neutralized by calcium carbonate in coarse particle mode during the Asian dust days. The clustered back trajectory analysis showed that the concentrations of nss-SO4, NO3-, and NH4 + were relatively high when the inflow pathway of air mass was from the southern part of China.

A sub-decadal trend in diacids in atmospheric aerosols in eastern Asia

Abstract. Change in secondary organic aerosols (SOAs) has been predicted to be highly uncertain in the future atmosphere in Asia. To better quantify the SOA change, we examine the sub-decadal (2001–2008) trend in major surrogate compounds (C2–C10 diacids) of SOA in atmospheric aerosols from Gosan site on Cheju Island, South Korea. The Gosan site is influenced by pollution outflows from eastern Asia. The molecular distributions of diacids were characterized by the predominance of oxalic (C2) acid followed by malonic (C3) and succinic (C4) acids in each year. The seasonal variations in diacids in each year were characterized by the highest concentrations of saturated diacids in spring and unsaturated diacids in winter. The consistent molecular distributions and seasonal variations along with significantly similar air mass transport patterns are indicative of similar pollution sources for diacids in eastern Asia on a sub-decadal scale. However, the intensity of the pollution sources has increased as evidenced by the increases in major diacids at the rate of 3.9–47.4 % per year, particularly in April. The temporal variations in atmospheric tracer compounds (carbon monoxide, levoglucosan, 2-methyltetrols, pinic acid, glyoxylic acid, glyoxal and methylglyoxal) suggest that the increases in diacids are due to enhanced precursor emissions associated with more anthropogenic than biogenic activities followed by the compounds' chemical processing in the atmosphere. The trends in diacids contrast with the reported decreases in sulfate, nitrate and ammonium in recent years in eastern Asia. This study demonstrates that recent pollution control strategies in eastern Asia were not able to decrease organic acidic species in the atmosphere. The increases in water-soluble organic acid fraction could modify the aerosol organic composition and its sensitivity to climate relevant physical properties.

제주도 고산지역 대기 에어로졸의 입경별 산성화-중화 특성

제주도 고산지역에서 2010~2011년에 대기 에어로졸을 입경별로 채취하여 산성화와 중화 특성을 조사하였다. 인위적 기원의 <TEX>$NH_4{^+}$</TEX>와 nss-<TEX>$SO_4{^{2-}}$</TEX>은 일반적으로 <TEX>$0.7{\sim}1.1{\mu}m$</TEX>의 극미세 입자에서 높은 농도를 보였으나, 황사 시에는 <TEX>$4.7{\sim}5.8{\mu}m$</TEX>의 조대입자 범위에서도 함께 농도가 높은 이산형 분포를 나타내어 황사와 비황사 간에 서로 다른 분포 패턴을 보였다. nss-<TEX>$Ca^{2+}$</TEX>과 <TEX>$NO_3{^-}$</TEX>은 <TEX>$3.3{\sim}4.7{\mu}m$</TEX>의 조대입자에서 높은 농도를 보였으며, 특히 <TEX>$NO_3{^-}$</TEX>은 미세입자와 조대입자 영역에서 농도가 높은 이산형 분포를 나타내었다. 고산지역 대기 에어로졸의 산성화는 황산과 질산 등 무기산에 의한 영향이 대부분이며, 유기산인 포름산과 아세트산은 1.6~6.4% 정도 산성화에 기여하는 것으로 확인되었다. 또한 암모니아, 탄산칼슘, 탄산마그네슘 등이 대기 에어로졸의 산성 물질 중화에 주로 관여하고 있으며, 특히 암모니아에 의한 중화는 비황사와 황사 기간 모두 미세입자 영역에서 훨씬 더 높은 기여도를 보였으나, 탄산칼슘은 조대입자 영역에서 더 큰 중화 기여도를 보였다. The size fractionated atmospheric aerosols have been collected at Gosan site of Jeju Island during 2010~2011, and then their characteristics of acidification and neutralization have been investigated. The anthropogenic <TEX>$NH_4{^+}$</TEX> and nss-<TEX>$SO_4{^{2-}}$</TEX> showed high concentrations mostly at ultra-fine particle mode of <TEX>$0.7{\sim}1.1{\mu}m$</TEX>, but they also had a bimodal distribution showing high concentrations at coarse particle mode of <TEX>$4.7{\sim}5.8{\mu}m$</TEX> during Asian Dust periods. The concentrations of nss-<TEX>$Ca^{2+}$</TEX> and <TEX>$NO_3{^-}$</TEX> were relatively high at coarse particle mode of <TEX>$3.3{\sim}4.7{\mu}m$</TEX>, especially <TEX>$NO_3{^-}$</TEX> showed high concentrations with a bimodal pattern at both fine and coarse particle modes. The acidification of atmospheric aerosols at Gosan area was contributed mostly by inorganic sulfuric and nitric acids, while the contribution by organic formic and acetic acids was only 1.6~6.4%. Furthermore, the neutralization of acidic species among atmospheric aerosols was performed mostly by <TEX>$NH_3$</TEX>, <TEX>$CaCO_3$</TEX> and <TEX>$MgCO_3$</TEX>, especially the neutralization by <TEX>$NH_3$</TEX> was high in fine particle mode, while that by <TEX>$CaCO_3$</TEX> was relatively high in coarse particle mode.

제주도 고산지역 CO2농도의 단기 변동에 영향을 미치는 요인 분석

This study examined the short-term variability of concentrations measured at the Gosan site (, ) in Jeju, Korea for the last 9 years from 2002 to 2010. The weekly distribution shows higher concentrations during weekends than weekdays which implies the impact of local emissions because Jeju Island is one of the top tourist attraction in Korea. In diurnal variation, concentration reached the maximum at 6 am and the minimum at 1 pm. The high concentrations were mostly associated with lower wind speed (below 4 m/s) and easterlies, which was typical of summer night. In other seasons, however, the high concentrations were encountered under strong westerlies (8~16 m/s), which implies the influence of Chinese outflows. concentrations were found to be highly correlated with meteorological parameters including wind speed, temperature, humidity, and solar radiation except for winter.

연무 에어로졸의 조성 및 기류 유입경로별 변화: 2012-2013년 제주도 고산지역 측정

Abstract: The atmospheric aerosols of PM 10 and PM 2.5 were collected at Gosan site of Jeju Island during 2012-2013. Their ionic and elemental species were analyzed in order to examine the composition variation of thehaze aerosols in accordance with the pathway of air mass. The concentrations of nss-SO 42− , NO 3− , and NH 4+ increased 2.1~3.7 times in coarse particle and 3.1~6.5 times in fine particle modes, respectively, showingespecially high NO 3− concentrations in fine particles during the haze days. The concentrations of S, Zn, Pband K increased 3.0~5.6 times in coarse particles and 3.2~7.7 times in fine particles during the haze days,on the other hand Al, Fe, and Ca concentrations were high only in coarse particles. Due to the back trajectoryanalysis, the concentrations of nss-SO 42− and NO 3− for haze days were high when the inflow pathway of airmass was from China, especially a high increase of NO 3− as through the south of China. The NO 3 /nss-SO 42 concentration ratio was relatively high in coarse mode as air mass inflow from China, but in fine mode itwas high as air mass passing through the Korean peninsula. 요약: 국내 배경지역인 제주도 고산측정소에서 2012~2013년에 대기 미세먼지를 채취하여 분석한 결과로부터 연무와 비현상일의 조성특성을 조사하였다. 연무 시 nss-SO

Comparison of the Number Concentration and the Chemical Composition of the Atmospheric PM2.5in Jeju Area

The number concentrations and the water soluble ionic concentrations of <TEX>$PM_{2.5}$</TEX> have measured at Gosan site in Jeju, Korea, from March 2010 to December 2010, to clarify their characteristics. <TEX>$PM_{2.5}$</TEX> number concentrations vary from 22.57 to <TEX>$975.65particles/cm^3$</TEX> with an average value of <TEX>$240.41particles/cm^3$</TEX>, which have been recorded evidently high in spring season as compared with those in other season. And the concentrations in small size ranges are greatly higher than those in large size ranges, so the number concentration in the size range <TEX>$0.25{\sim}0.45{\mu}m$</TEX> has more than 94% of the total number concentration of <TEX>$PM_{2.5}$</TEX>. The major ionic components in <TEX>$PM_{2.5}$</TEX> are <TEX>$SO{_4}^{2-}$</TEX>, <TEX>$NH_4{^+}$</TEX> and <TEX>$NO_3{^-}$</TEX>, which are mainly originated from anthropogenic sources, on the other hand, the concentrations of <TEX>$Cl^-$</TEX>, <TEX>$K^+$</TEX>, <TEX>$Ca^{2+}$</TEX> and <TEX>$Mg^{2+}$</TEX> are recorded relatively lower levels. The concentrations of the major ionic components are very high in spring season, but the concentration levels of the other components are recorded significantly high in winter season. On the other hand, in summer season, the lowest concentration levels are observed for overall components as well as the sum of them. The concentration ratios of nss-<TEX>$SO{_4}^{2-}/SO{_4}^{2-}$</TEX> and nss-<TEX>$Ca^{2+}/Ca^{2+}$</TEX> are 98.1% and 88.9%. And the concentration ratio of <TEX>$SO{_4}^{2-}/NO_3{^-}$</TEX>(3.64) is greatly higher than the value in urban area due to no large <TEX>$NO_x$</TEX> emission sources in the measurement. In addition, the correlation and the factor analysis for the number and the ionic concentrations of <TEX>$PM_{2.5}$</TEX> are performed to identify their sources. From the Pearson correlation analysis and the factor analysis, it can be suggested that the smaller parts(< <TEX>$0.5{\mu}m$</TEX>) of <TEX>$PM_{2.5}$</TEX> is contributed by anthropogenic sources, but the sources of the remaining larger parts of <TEX>$PM_{2.5}$</TEX> are not able to be specified sources in this study.

Seasonal variations of stable carbon isotopic composition of bulk aerosol carbon from Gosan site, Jeju Island in the East China Sea

This study explores the usefulness of stable isotopic composition (δ13C) along with other chemical tracers and air mass trajectory to identify the primary and secondary sources of carbonaceous aerosols. Aerosol samples (n = 84) were collected continuously from April 2003 to April 2004 at Gosan site in Jeju Island, South Korea. The concentrations of total carbon (TC), HCl fumed carbonate-free total carbon (fumed-TC) and their δ13C were measured online using elemental analyzer interfaced to isotope ratio mass spectrometer (EA-IRMS). Similar concentrations of TC and fumed-TC and their similar δ13C values suggest the insignificant contribution of inorganic carbon to Gosan aerosols. The monthly averaged δ13CTC showed the lowest in April/May (−24.2 to −24.4‰), which is related with the highest concentrations of oxalic acid (a secondary tracer). The result indicates an enhanced contribution of TC from secondary sources. The monthly averaged δ13CTC in July/August (−23.0 to −22.5‰) were similar to those in January/February (−23.1‰ to −22.7‰). However, chemical tracers and air mass transport pattern suggest that the pollution source regions in January/February are completely different from those in July/August. Higher δ13C values in July/August are aligned with higher concentration ratios of marine tracers (azelaic acid/TC and methanesulfonate/TC), suggesting an enhanced contribution of marine organic matter to the aerosol loading. Higher δ13C values in January/February are associated with higher concentrations of phthalic acid and K+/TC, indicating more contributions of carbonaceous aerosols from fossil fuel and C4-plant biomass combustion. This study demonstrates that δ13CTC, along with other chemical tracers and air mass trajectory, can be used as a tracer to understand the importance of primary versus secondary pollution sources of carbonaceous aerosols in the atmosphere.

제주지역 PM10의 수농도 및 질량농도와 원소성분 조성 특성

The number concentrations, the mass concentrations and the elemental concentrations of PM10 have measured at Gosan site in Jeju, Korea, from March 2010 to December 2010. And the correlation and the factor analysis for the number, the mass and the elemental concentrations of PM10 are performed to identify their relationships and sources. The average PM10 number concentration is observed 246 particles/cm(35.7∼1,017 particles/cm) and the average PM10 mass concentration is shown 50.1 μg/m3(16.7∼441.4 μg/m3) during this experimental period. The number concentrations are significantly decreased with increasing particle size, hence the concentrations for the smaller particles less than 2.5 μm(PM2.5) are contributed 99.6% to the total PM10 number concentrations. The highest concentration of the 20 elements in PM10 determined in this study is shown by S with a mean value of 1,497 ng/m3 and the lowest concentration of them is found by Cd with a mean value of 0.57 ng/m3. The elements in PM10 are evidently classified into two group based on their concentrations: In group 1, including S>Na> Al>Fe>Ca>Mg>K, the elemental mean concentrations are higher than several hundred ng/m3, on the other hand, the concentrations are lower than several ten ng/m3 in group 2, including Zn>Mn>Ni>Ti>Cr>Co>Cu>Mo>Sr>Ba>V >Cd. The size-separated number concentrations are shown positively correlated with the mass concentrations in overall size ranges, although their correlation coefficients, which are monotonously increased or decreased with size range, are not high. The concentrations of the elements in group 1 are shown highly correlated with the mass concentrations, but the concentrations in group 2 are shown hardly correlated with the mass concentrations. The elements originated from natural sources have been predominantly related to the mass concentrations while the elements from anthropogenic sources have mainly affected on the number concentrations of PM10.

황사와 연무 시 PM10및 PM2.5미세먼지 조성 비교: 2010-2011년 고산지역 측정

제주도 고산측정소에서 <TEX>$PM_{10}$</TEX>, <TEX>$PM_{2.5}$</TEX> 미세먼지를 채취하여 주요 성분을 분석한 결과로부터 입경분포 및 오염 특성을 조사하였다. <TEX>$NH{_4}{^+}$</TEX>, nss-<TEX>$SO{_4}^{2-}$</TEX>, <TEX>$K^+$</TEX>, <TEX>$CH_3COO^-$</TEX>은 대체적으로 미세입자 분포하고, <TEX>$NO{_3}{^-}$</TEX>은 조대와 미세입자에 고루 분포하였으나 <TEX>$Na^+$</TEX>, <TEX>$Cl^-$</TEX>, <TEX>$Mg^{2+}$</TEX>, nss-<TEX>$Ca^{2+}$</TEX>은 대부분 조대입자에 분포되는 경향을 보였다. 황사 시에 조대입자와 미세입자에서 nss-<TEX>$Ca^{2+}$</TEX>이 36.7배, 15.0배 증가하고, <TEX>$NO{_3}{^-}$</TEX>은 조대입자에서 3.2배, 미세입자에서 3.1 배 높았다. 또 Al, Fe, Ca, K, Mg, Ti, Mn, Sr, Ba의 농도도 크게 증가하였다. 연무 시에는 nss-<TEX>$SO{_4}^{2-}$</TEX>, <TEX>$NO{_3}{^-}$</TEX>, <TEX>$NH{_4}{^+}$</TEX> 농도가 조대입자에서 1.3~2.6배, 미세입자에서 1.5~4.2배 상승하였고, 특히 미세입자에서 <TEX>$NO{_3}{^-}$</TEX> 농도가 크게 상승하였다. 고산지역 미세입자의 오염원 특성을 조사한 결과, 조대입자는 해염 영향이 가장 크고, 다음으로 토양, 인위적 오염원 순으로 영향을 많이 받았으나 미세입자는 인위적인 오염원 영향이 더 크고, 다음으로 해양과 토양 유입의 영향을 많이 받고 있는 것으로 나타났다. The <TEX>$PM_{10}$</TEX> and <TEX>$PM_{2.5}$</TEX> samples were collected at Gosan Site of Jeju Island, and analyzed, in order to investigate the size distribution and pollution characteristics of their components. <TEX>$NH{_4}{^+}$</TEX>, nss-<TEX>$SO{_4}^{2-}$</TEX>, <TEX>$K^+$</TEX>, and <TEX>$CH_3COO^-$</TEX> were mostly existed in fine particles. Meanwhile, <TEX>$NO{_3}{^-}$</TEX> was distributed in both fine and coarse particles, and <TEX>$Na^+$</TEX>, <TEX>$Cl^-$</TEX>, <TEX>$Mg^{2+}$</TEX>, nss-<TEX>$Ca^{2+}$</TEX> were rich in coarse particle mode. The concentrations of nss-<TEX>$Ca^{2+}$</TEX> and <TEX>$NO{_3}{^-}$</TEX> were increased 36.7 and 3.2 times in coarse particles, and 15.0 and 3.1 times in fine particles during the Asian Dust periods. Especially, the concentrations of crustal elemental species such as Al, Fe, Ca, K, Mg, Ti, Mn, Sr, Ba were highly increased for those periods. In the haze events, the concentrations of secondary air pollutants were increased 1.3~2.6 and 1.5~4.2 times in coarse and fine particles, respectively. Moreover, the remarkable increase of <TEX>$NO{_3}{^-}$</TEX> concentration was also observed in fine particle mode. The factor analysis showed that the composition of coarse particles was influenced mainly by marine sources, followed by soil and anthropogenic sources. On the other hand, the fine particles were influenced by anthropogenic sources, followed by marine and soil sources.

Aerosol properties and associated regional meteorology during winter pollution event at Gosan climate observatory, Korea

This paper describes aerosol optical and physical properties and the corresponding meteorological analysis during a winter-time fine aerosol event at a regional background station, Gosan, in Korea. Spatio-temporal distributions of air pollutants over Northeast Asia during winter are governed by continental outflows; however, winter is the highest in magnitude (9.5 ± 8.7 Mm−1) of aerosol absorption coefficient (σa) among other seasons and the second highest in magnitude (105.3 ± 104.8 Mm−1) of aerosol scattering coefficient (σs) after spring at the Gosan site. Values for σs and σa at Gosan during the winter polluted period (WPP; January 3 to 10, 2008) were recorded as 238.97 ± 123.85 and 18.42 ± 8.49 Mm−1, respectively, which were approximately 5 times greater than those during the winter clean period (WCP; January 13 to 16, 2008) of this study. An ensemble analysis of the OMI aerosol index, wind vectors and background trajectories during the WPP reveals that a slow-moving anticyclonic system, preceded by a frontal system, brought heavy aerosol loading from the Asian continent to the Gosan site. Space-based lidar CALIOP observations support the presence of heavy loadings of aerosol and pollutant plumes over the Yellow sea, before arriving at the Gosan.

Seasonal Composition Characteristics of TSP and PM2.5 Aerosols at Gosan Site of Jeju Island, Korea during 2008-2011

The collection of TSP and <TEX>$PM_{2.5}$</TEX> aerosols has been made at the Gosan Site of Jeju Island during 2008-2011, and their ionic and elemental species were analyzed, in order to examine the seasonal variation and characteristics of aerosol compositions. The anthropogenic components (<TEX>$NH_4{^+}$</TEX>, <TEX>$nss-SO_4{^{2-}}$</TEX>, <TEX>$NO_3{^-}$</TEX>, S, Zn, Pb) and the soil components (<TEX>$nss-Ca^{2+}$</TEX>, Al, Fe, Ca) showed high concentrations in spring as the prevailing westerly wind, but the concentrations of the sea-salt components (<TEX>$Na^+$</TEX>, <TEX>$Cl^-$</TEX>) were high in winter. In TSP, the neutralization by <TEX>$NH_3$</TEX> increased in summer, but the neutralization by <TEX>$CaCO_3$</TEX> increased in spring and fall seasons. The organic acids (<TEX>$HCOO^-$</TEX>, <TEX>$CH_3COO^-$</TEX>) contributed to the acidification of the aerosols by only 5.0%, so the acidification could be mostly contributed by the inorganic acids (<TEX>$SO_4{^{2-}}$</TEX>, <TEX>$NO_3{^-}$</TEX>). From the examination of the source origins by factor analysis, the compositions of TSP were influenced by the order of soil > anthropogenic > marine, on the other hand, those of <TEX>$PM_{2.5}$</TEX> were by the order of anthropogenic > marine > soil. The backward trajectory analyses showed that the concentrations of <TEX>$NH_4{^+}$</TEX>, <TEX>$nss-SO_4{^{2-}}$</TEX>, <TEX>$NO_3{^-}$</TEX> and <TEX>$nss-Ca^{2+}$</TEX> increased highly when the air masses had moved from China continent into Gosan area of Jeju Island.

2010년 봄철 고농도 황사의 입경별 화학조성 특성

The size-fractionated aerosol samples have been collected at Gosan Site of Jeju Island during the spring season of 2010, in order to examine the chemical composition characteristics of the Asian Dust and Non-Asian Dust particles. The concentrations of , Al, and nss- in had tremendously increased during the heavy Asian Dust (March 20, 2010). The concentration ratios of Asian Dust to Non-Asian Dust for the soil species (nss-, , Al, Fe, Ti, Mn) were 12.2~30.7, meanwhile those for the anthropogenic species (nss-, , , , Zn, Pb, and Cu) were 2.9~7.8. During the heavy Asian Dust event, the concentration increase of in were much more apparent than those of nss- and , and the soil species (nss- and ) showed much higher concentration increase. The neutralization factor of was higher than that of . However, the neutralization factor of in was exceptionally high during the heavy Asian Dust, showing the evidence of heavy migration of soil particles. From the study for size fractionated particles, it was found that nss- and were mostly distributed in fine particle mode, on the other hand, existed evenly in both fine and coarse particle modes, and the soil species (nss-, Al, Fe, etc.) were mainly in the latter mode. During the heavy Asian Dust, in particular, the concentrations of , nss-, , Zn, and Pb had increased in coarse particle mode as well.

제주도 고산측정소의 대기 라돈농도 시계열 변화

The realtime monitoring of radon () concentrations has been carried out from Gosan site, Jeju Island for three years of 2006~2008, in order to evaluate the background level and timely variational characteristics of atmospheric radon. The mean concentration of radon measured during the studying period was with its annual mean values in the range of . The relative ordering of the seasonal mean concentrations was seemed to vary such as winter () > fall () > spring () > summer (). The monthly mean concentrations were in the order of Jan>Feb>Oct>Nov>Dec>Mar> Sep>Apr>May>Jun>Aug>Jul, so that the highest January value () exceeded almost twice as the July minimum (). The hourly concentrations in a day showed the highest level () at around 7 a.m., increasing during nighttime, while reaching the lowest () at around 3 p.m. From the backward trajectory analysis for a continental fetch of radon, the high concentrations (10%) of radon matched with the air mass moving from the Asia continent to Jeju area. In contrast, the low concentrations (10%) of radon were generally correlated with the air mass of the North Pacific Ocean. In comparison by sectional inflow pathways of air mass, the radon concentrations were relatively high from the north China and the Korean peninsula.

대기배경지역 에어로졸의 입경별 수농도 연속 측정

The aerosol number concentration have measured with an aerodynamic particle sizer spectrometer(APS) at Gosan site, which is known as background area in Korea, from January to September 2011. The temporal variation and the size distribution of aerosol number concentration have been investigated. The entire averaged aerosol number concentration in the size range 0.25~32.0 <TEX>${\mu}m$</TEX> is about 252 particles/<TEX>$cm^3$</TEX>. The number concentration in small size ranges(<TEX>${\leq}0.5{\mu}m$</TEX>) are very higher than those in large size ranges, such as, the number concentration in range of larger than 6.5 <TEX>${\mu}m$</TEX> are almost zero particles/<TEX>$cm^3$</TEX>. The contributions of the number concentration to PM10 and/or PM2.5 are about 34%, 20.1% and 20.4% in the size range 0.25~0.28 <TEX>${\mu}m$</TEX>, 0.28~0.30 <TEX>${\mu}m$</TEX> and 0.30~0.35 <TEX>${\mu}m$</TEX>, respectively, however, the contributions are below 1% in range of larger than 0.58 <TEX>${\mu}m$</TEX>. The monthly variations in the number concentration in smaller size range(<1.0 <TEX>${\mu}m$</TEX>) are evidently different from the variations in range of larger than 1.0 <TEX>${\mu}m$</TEX>, but the variations are appeared similar patterns in smaller size range(<1.0 <TEX>${\mu}m$</TEX>), also the variations in range of larger than 1.0 <TEX>${\mu}m$</TEX> are similar too. The diurnal variations in the number concentration for smaller particle(<1.0 <TEX>${\mu}m$</TEX>) are not much, but the variations for larger particle are very evident. Size-fractioned aerosol number concentrations are dramatically decreased with increased particle size. The monthly differences in the size-fractioned number concentrations for smaller size range(<0.7 <TEX>${\mu}m$</TEX>) are not observed, however, the remarkable monthly differences are observed for larger size than 0.7 <TEX>${\mu}m$</TEX>.

제주도 고산지역의 라돈 배경농도 실시간 모니터링

제주도 고산지역에서 라돈(<TEX>$^{222}Rn$</TEX>)을 실시간 모니터링하여 대기 중의 배경농도 수준을 확인하였다. 고산지역의 라돈 농도는 평균 2831 <TEX>$mBq/m^3$</TEX> (0.077 pCi/L)로 우리나라 실내 평균농도보다는 19.5배 낮은 배경농도 수준을 나타내었다. 계절별로는 봄, 여름, 가을, 겨울에 각각 2657, 2071, 3249, 3384 <TEX>$mBq/m^3$</TEX> 농도를 보여 겨울에 높고 여름에 낮은 것으로 조사되었다. 월별로는 10월에 가장 높고 7월에 가장 낮은 농도를 나타내었다. 일간 농도는 오전 7시에 하루 중 가장 높은 농도를 보였고, 오후 2~3시경에 가장 낮은 농도를 나타내는 것으로 확인되었다. 역궤적 분석 결과, 라돈 농도는 기류의 유입경로에 따라 차이를 보였고, 아시아대륙으로부터 제주도로 이동했을 때 농도가 높고 북태평양으로부터 기류가 유입될 때 훨씬 더 낮은 농도를 나타내었다. The real-time monitoring of radon (<TEX>$^{222}Rn$</TEX>) concentrations has been carried out to evaluate the background concentration level of atmospheric radon in Gosan site, Jeju Island. The mean concentration of radon for the recent 10 years was 2831 <TEX>$mBq/m^3$</TEX> (0.077 pCi/L), which was 19.5 time lower than that of indoor radon in Korea. The seasonal concentrations were 2657, 2071, 3249, 3384 <TEX>$mBq/m^3$</TEX> respectively for spring, summer, fall, and winter seasons. In monthly comparison, the radon concentrations were high in October and low in July. The hourly concentrations have increased during the nighttime, showing 3666 <TEX>$mBq/m^3$</TEX> at 7 a.m., and decreased relatively during the daytime, showing 2755 <TEX>$mBq/m^3$</TEX> at 2~3 p.m. From the back trajectory analysis, the radon concentrations showed higher values when the air mass was moved from the Asia continent to Jeju area, on the other hand, it showed low values when it was moved from the North Pacific Ocean.