• 한국환경과학회지
• /
• 제22권6호
• /
• pp.651-666
• /
• 2013

This study introduces a novel approach to the differentiation of two phenomena, Asian Dust and haze, which are extremely difficult to distinguish based solely on comparisons of PM10 concentration, through use of the Optical Particle Counter (OPC), which simultaneously generates PM10, PM2.5 and PM1.0 concentration. In the case of Asian Dust, PM10 concentration rose to the exclusion of PM2.5 and PM1.0 concentration. The relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration were below 40%, which is consistent with the conclusion that Asian Dust, as a prime example of the coarse-particle phenomenon, only impacts PM10 concentration, not PM2.5 and PM1.0 concentration. In contrast, PM10, PM2.5 and PM1.0 concentration simultaneously increased with haze. The relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration were generally above 70%. In this case, PM1.0 concentration varies because a haze event consists of secondary aerosol in the fine-mode, and the relative ratios of PM10 and PM2.5 concentration remain intact as these values already subsume PM1.0 concentration. The sequential shift of the peaks in PM10, PM2.5 and PM1.0 concentrations also serve to individually track the transport of coarse-mode versus fine-mode aerosols. The distinction in the relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration in an Asian Dust versus a haze event, when collected on a national or global scale using OPC monitoring networks, provides realistic information on outbreaks and transport of Asian Dust and haze.

• 한국입자에어로졸학회지
• /
• 제15권2호
• /
• pp.45-56
• /
• 2019

The public's concern on ambient $PM_{2.5}$ has been increasing in Korea. We have estimated (1) the annual and monthly mean $PM_{2.5}$ concentrations, (2) the frequency by the $PM_{2.5}$ concentration interval, and (3) the high concentration occurrence duration time between 2015 and 2018 at 16 administration regions. We found that there have been differences in all three above parameters' trends among the studied 16 regions in Korea. Still, Jeonbuk showed the highest rank in all three parameters' trends. In Jeonbuk, the average $PM_{2.5}$ concentration and the sum of the frequency fraction when the $PM_{2.5}$ concentration being over $75{\mu}g/m^3$ between 2016 and 2018 was $28.4{\mu}g/m^3$ and 9.0%, respectively. And the days when the $PM_{2.5}$ concentration is over $50{\mu}g/m^3$ between 2015 and 2018 were 149. Chungbuk was the only region with the increasing trend of $PM_{2.5}$ concentration between 2016 and 2018. And in Seoul and Gyeonggi, the average $PM_{2.5}$ concentrations decreased whereas the high concentration frequency fraction increased between 2016 and 2018. Also, it is found that there have been differences in the trends of the frequency by the $PM_{2.5}$ concentration interval and the high concentration occurrence duration time between $PM_{10}$ and $PM_{2.5}$.

• 한국환경보건학회지
• /
• 제45권2호
• /
• pp.186-191
• /
• 2019

Objectives: Subway is one of the most common transportation modes in Seoul, Korea. The objectives of this study were to determine characteristics of in-cabin $PM_{2.5}$ concentration in Seoul Metro Line Number 2 and to identify factors of the $PM_{2.5}$ concentration. Methods: In-cabin $PM_{2.5}$ concentrations in Seoul Metro Line Number 2 were measured using real-time monitors and the factors affecting $PM_{2.5}$ concentration in cabin were observed. Linear regression analysis of in-cabin $PM_{2.5}$ concentration and indoor/outdoor (I/O) ratio were performed. Results: In-cabin $PM_{2.5}$ concentration was associated with the in-cabin $PM_{2.5}$ concentration in previous station. In-cabin $PM_{2.5}$ concentration was correlated with ambient $PM_{2.5}$ concentration and associated with underground station with control of the in-cabin $PM_{2.5}$ concentration in previous station. I/O ratio increased as the number of passengers increased and when passing through the underground station with control of I/O ratio in previous station. Conclusion: In-cabin $PM_{2.5}$ concentration was affected by ambient $PM_{2.5}$ concentration. Therefore, management of in-cabin $PM_{2.5}$ concentrations should be based on outdoor air quality.

• 한국환경과학회지
• /
• 제29권7호
• /
• pp.749-760
• /
• 2020

This study investigates the characteristics of diurnal, seasonal, and weekly roadside and residential concentrations of PM₁₀ and PM_2.5 in Busan, as well as relationship with meteorological phenomenon. Annual mean PM₁₀ and PM_2.5 concentrations in Busan were 44.2 ㎍/㎥ and 25.3 ㎍/㎥, respectively. The PM_2.5/PM₁₀ concentration ratio was 0.58. Diurnal variations of PM₁₀ and PM_2.5 concentrations in Busan were categorized into three types, depending on the number of peaks and times at which the peaks occurred. Roadside PM₁₀ concentration was highest on Saturday and lowest on Friday. Residential PM₁₀ concentration was highest on Monday and lowest on Friday. Residential PM_2.5 concentration was highest on Monday and Tuesday and lowest on Friday. PM₁₀ and PM_2.5 concentrations were highest on Asian dust and haze, respectively. The results indicate that understanding the spaciotemporal variation of fine particles could provide insights into establishing a strategy to control urban air quality.

• 한국환경과학회지
• /
• 제19권8호
• /
• pp.1013-1023
• /
• 2010

The purpose of this study was to analyze the characteristics of spacio-temporal variation for $PM_{10}$ and $PM_{2.5}$ concentration in Busan. $PM_{10}$ concentration has been reduced for the past three year and exceeded $50\;{\mu}g/m^3$ of the national standard for $PM_{10}$. $PM_{2.5}$ concentration showed gradual decrease or stagnant trends and exceeded the U.S. EPA standard. Seasonal analysis of $PM_{10}$ and $PM_{2.5}$ suggested spring>winter>fall>summer(by Asian dust) and winter>spring>summerenlifall(by anthropogenic effect) in the order of high concentration, respectively. Characterization of diurnal variations suggests that $PM_{10}$ levels at all the three sites consistently exhibited a peak at 1000LST and $PM_{2.5}$ at Jangrimdong experienced the typical $PM_{2.5}$ diurnal trends such that a peak was observed in the morning and the lowest level at 1400LST. In the case of seasonal trends, the $PM_{2.5}/PM_{10}$ ratio was in the order of summer>winter>fall>spring at all the study sites, with a note that spring bears the lowest concentration. During AD events, $PM_{10}$ concentration exhibited the highest level at Jangrimdong and the lowest level at Joadong. And $PM_{2.5}/PM_{10}$ ratio in AD was 0.16~0.28.

• 한국환경과학회지
• /
• 제23권5호
• /
• pp.819-827
• /
• 2014

This study analyzes the chemical composition of metallic elements and water-soluble ions in $PM_{10}$ and $PM_{2.5}$. $PM_{10}$ and $PM_{2.5}$ concentrations in Busan during 2010-2012 were $97.2{\pm}67.5$ and $67.5{\pm}32.8{\mu}g/m^3$, respectively, and the mean $PM_{2.5}/PM_{10}$ concentration ratio was 0.73. The contribution rate of water-soluble ions to $PM_{10}$ ranged from 29.0% to 58.6%(a mean of 38.6%) and that to $PM_{2.5}$ ranged from 33.9% to 58.4%(a mean of 43.1%). The contribution rate of sea salt to $PM_{10}$ was 13.9% for 2011 and 9.7% for 2012, while that to $PM_{2.5}$ was 17.4% for 2011 and 10.1% for 2012. $PM_{10}$ concentration during Asian dust events was $334.3{\mu}g/m^3$ and $113.3{\mu}g/m^3$ during non-Asian dust events, and the $PM_{10}$ concentration ratio of Asian Dust/Non Asian dust was 2.95. On the other hand, the $PM_{2.5}$ concentration in Asian dust was $157.4{\mu}g/m^3$ and $83.2{\mu}g/m^3$ in Non Asian dust, and the $PM_{2.5}$ concentration ratio of Asian Dust/Non Asian dust was 1.89, which was lower than that of $PM_{10}$.

• 한국환경과학회지
• /
• 제24권6호
• /
• pp.777-784
• /
• 2015

This study investigates weekday/weekend characteristics of $PM_{10}$ and $PM_{2.5}$ concentration and metallic elements in Busan in the springtime of 2013. $PM_{10}$ concentration on weekday/weekend were 77.54 and $67.28{\mu}g/m^3$, respectively. And $PM_{2.5}$ concentration on weekday/weekend were 57.81 and $43.83{\mu}g/m^3$, respectively. Also, $PM_{2.5}/PM_{10}$ concentration ratio on weekdays/weekend was 0.75 and 0.65, respectively. The contribution rates of Na to total metallic elements in $PM_{10}$ on weekday/weekend were 38.3% and 38.9%, respectively. It would be useful in control effectively with management of urban fine particle to understand characteristics of fine particle concentration on weekday/weekend.

• 한국지구과학회지
• /
• 제33권6호
• /
• pp.469-480
• /
• 2012

본 연구는 3년(2005. 12. 1-2008. 11. 30) 동안 부산의 $PM_{2.5}$ 대기오염자동관측소(장림동: 공업지역, 좌동: 주거지역) 측정자료 중 고농도 $PM_{2.5}$(24시간 환경기준 $50{\mu}g/m^3$)에 대한 $PM_{2.5}$ 및 $PM_{2.5}/PM_{10}$ 농도비의 일변화 특성과 함께 시 공간적 풍계(풍향 및 풍속)에 따른 특성을 분석하고자 하였다. 고농도 $PM_{2.5}$는 장림동과 좌동 각각 182일 및 27일이었다. 장림동에서 고농도 $PM_{2.5}$의 시간평균농도 및 $PM_{2.5}/PM_{10}$ 농도비의 일변화는 모든 계절에서 오후에 비해 새벽과 오전 및 야간에 높은 비슷한 패턴을 나타내었다. 좌동의 여름 주간에 $PM_{2.5}/PM_{10}$ 농도비가 증가하는 것은 해양조건에서 광화학반응에 의해 생성되는 이차 입자상물질 중 $PM_{10}$의 거대입자 농도가 미세입자인 $PM_{2.5}$ 농도보다 더 감소하기 때문이다. 시간대별로 시 공간적 풍계(풍향 및 풍속등급) 특성을 분석하였다. 그 결과, 고농도 $PM_{2.5}$는 장림동에서 공업단지의 산업활동에 의한 오염물질 정체와 주변지역의 오염물질 이동에 의해 발생되었다. 좌동에서는 주로 주거와 상업활동으로 인한 지역적 오염물질 정체로 발생하는 것으로 나타났다.

• 한국대기환경학회지
• /
• 제34권1호
• /
• pp.156-165
• /
• 2018

Long-term trend analysis on air pollutant concentrations is very important to diagnose the present status and plan for the future. In this study, the long-term trends of $PM_{2.5}$ concentrations were estimated based on the relationship between the visibility and $PM_{2.5}$ concentration regarding the effects of relative humidity in Seoul and Chuncheon. The relationships between the visibility and $PM_{2.5}$ concentration were derived from the measurement data in 2015 and 2016. Then, the annual trends of $PM_{2.5}$ concentration from 1982 to 2014 were estimated and compared to those of $PM_{10}$ concentration available in Seoul and Chuncheon. During the estimation process, four ranges of relative humidity were considered such as less than 30%, 31~50%, 51~70%, and 71~90%. In Seoul and Chuncheon, the visibility and $PM_{2.5}$ concentration generally have the inverse relationship while the visibility decreases as the relative humidity increases. The estimated $PM_{2.5}$ concentrations similarly showed the decreasing tendencies from 2006 to 2012 in Seoul and Chuncheon. However, the estimated $PM_{2.5}$ concentrations showed the increasing tendency before 2005 in Chuncheon in contrast to the decreasing tendency in Seoul. This implies that the long-term trends of $PM_{2.5}$ concentration in different cities in South Korea reflect the local influencing factors. For example, 'Special Act on the Improvement of Atmospheric Environment in the Seoul Metropolitan Area' can affect the different long-term trends in Seoul and Chuncheon. The estimated $PM_{2.5}$ concentrations were validated with the measured ones in Seoul and Chuncheon. While the general tendencies were well matched between the estimated and measured concentrations, the $PM_{2.5}$ concentration trends in 1990s and their monthly variations are needed to be improved quantitatively using more reference data for longer years.

• 한국환경과학회지
• /
• 제27권7호
• /
• pp.577-586
• /
• 2018

This research investigated the characteristics of $PM_{10}$ and $PM_{2.5}$ concentration at roadside (Choryangdong) and residential (Sujeongdong) locations in Busan. The $PM_{10}$ concentration at roadside and residential locations were 50.5 and $42.9{\mu}g/m^3$, respectively, and $PM_{2.5}$ at roadside and residential were 28.1 and $23.9{\mu}g/m^3$, respectively. The roadside/residential ratio of $PM_{10}$ and $PM_{2.5}$ concentration were 1.18, and the $PM_{2.5}/PM_{10}$ ratio at roadside and residential were 0.55 and 0.56, respectively. The $PM_{10}$ concentration in spring at roadside were $64.6{\mu}g/m^3$, and were the highest, followed by $48.0{\mu}g/m^3$ and $45.2{\mu}g/m^3$ in winter and summer. Number of exceedances per year of the daily limit value for $PM_{10}$ at roadside and residential were 66 and 39 days, respectively. The $PM_{10}$ and $PM_{2.5}$ concentration, and $PM_{2.5}/PM_{10}$ ratio at roadside were $53.0{\mu}g/m^3$, $29.0{\mu}g/m^3$ and 0.55 for day, and $45.5{\mu}g/m^3$, $26.7{\mu}g/m^3$ and 0.59 for night, respectively. These results indicate that understanding the relationship between roadside and residential could provide insight into establishing a strategy to control urban air quality.