항공관측 및 대기질 모델링을 통한 L TP 영향 산정

장임석(Lim-Seok Chang),성경희(Kyoung-Hee Sung),최진수(Jin-Su Choi),반수진(Soo-Jin Ban),안준영(Joon-Young Ahn),서석준(Seok-Jun Seo),김수연(Su-Yeon Kim) 한국환경관리학회 2010 環境管理學會誌 Vol.16 No.2

본 연구는 한반도 주변지역 장거리 이동 대기오염물질의 특성파악과 중국으로부터 이동되어 오는 장거리 이동 대기오염물질이 한반도 대기질에 미치는 영향을 평가하고 그 원인 규명을 통하여 과학적인 저감대책을 수립하는 것이 최종 목적이다. 이러한 목적을 위하여 항공기를 이용하여 서해 상공에서 대기오염물질의 측정과 집중측정 기간에 대한 상층기상 및 종관 분석을 수행하였다. 1997~2009년까지 측정기간 중 서해상에 영향을 준 기류의 48%가 Ⅱ권역의 영향이었고 기류의 이동경로 별로 뚜렷한 농도 차이를 보였다. 그 외 권역은 1.09~3.78 ppb의 범위를 보였고 Ⅱ, Ⅲ권역 사례의 7~25%, 4~15%에 불과하여 권역 Ⅱ, Ⅲ을 영향을 SO₂ 고농도 사례의 주요 원인으로 생각할 수 있다. 또한 권역별 기류에 따른 이동량을 분석한 결과, SO₂의 경우 측정기간 중 유입량은 유출량의 약 5배로 서해안이 중국으로부터 이동하는 SO₂의 직접적인 영향을 받고 있는 것으로 나타났다. To estimate the long-range transboundary air pollutants, aircraft measurements, upper and synoptic atmosphere analysis, and modeling have been performed. Flight measurement was carried out over the West Sea of Korea when westerly winds to identify the impact of air pollutants from China on air quality in Korea and to estimate the transboundary influx of air pollutants. In this year, it was found that long-range air pollutants were transported in various patterns. On April 17, a high concentration appeared in two different layers, while on October 16 a high concentration occurred in all sections due to the stagnation of the pollutants. As a result of back trajectory analysis by region, 48 percent of the total air currents affecting air quality over the West Sea during the observation periods (1997~2009) came from Region Ⅱ, with the concentrations of each transport track distinctively different. The modeling was conducted using MM5, SMOKE, and CMAQ. The impact of long-range air pollutants on local air quality was examined through emissions sensitivity analysis for the spring (Mar.~May) and Autumn (Sep.~Nov.) of 2009. In spring, about 18~65% of the total PM10 concentration was influenced by long-range transported air pollutants, while in autumn from 11 to 51% of the PM₁? concentration was affected. These results will be better estimated through the constant improvement of emission data. For the accuracy of the modeling work, a preliminary study should be done first, including improvement of emission inventories, identification of complex aerosol and photochemical reaction mechanism in the atmosphere, and establishment of contribution assessment methodology.

두 층 관측 기상인자의 주성분-다중회귀분석으로 도출되는 고농도 미세먼지의 부산-서울 지역차이 해석

최다니엘(Daniel Choi),장임석(Lim-Seok Chang),김철희(Cheol-Hee Kim) 한국기상학회 2021 대기 Vol.31 No.1

In this study, two-step statistical approach including Principal Component Analysis (PCA) and Multiple Linear Regression (MLR) was employed, and main meteorological factors explaining the high-PM<SUB>2.5</SUB> episodes were identified in two regions: Seoul and Busan. We first performed PCA to isolate the Principal Component (PC) that is linear combination of the meteorological variables observed at two levels: surface and 850 hPa level. The employed variables at surface are: temperature (T<SUB>2m</SUB>), wind speed, sea level pressure, south-north and west-east wind component and those at 850 hPa upper level variables are: south-north (v<SUB>850</SUB>) and west-east (u<SUB>850</SUB>) wind component and vertical stability. Secondly we carried out MLR analysis and verified the relationships between PM<SUB>2.5</SUB> daily mean concentration and meteorological PCs. Our two-step statistical approach revealed that in Seoul, dominant factors for influencing the high PM<SUB>2.5</SUB> days are mainly composed of upper wind characteristics in winter including positive u<SUB>850</SUB> and negative v<SUB>850</SUB>, indicating that continental (or Siberian) anticyclone had a strong influence. In Busan, however, the dominant factors in explanaining in high PM<SUB>2.5</SUB> concentrations were associated with high T<SUB>2m</SUB> and negative u<SUB>850</SUB> in summer. This is suggesting that marine anticyclone had a considerable effect on Busan’s high PM<SUB>2.5</SUB> with high temperature which is relevant to the vigorous photochemical secondary generation. Our results of both differences and similarities between two regions derived from only statistical approaches imply the high-PM<SUB>2.5</SUB> episodes in Korea show their own unique characteristics and seasonality which are mostly explainable by two layer (surface and upper) mesoscale meteorological variables.

WRF-Chem 모형을 이용한 한반도 대기질 모의

이재형(Jae-Hyeong Lee),장임석(Lim-Seok Chang),이상현(Sang-Hyun Lee) 한국기상학회 2015 대기 Vol.25 No.4

There is an increasing need to improve the air quality over South Korea to protect public health from local and remote anthropogenic pollutant emissions that are in an increasing trend. Here, we evaluate the performance of the WRF-Chem (Weather Research and Forecasting-Chemistry) model in simulating near-surface air quality of major Korean cities, and investigate the impacts of time-varying chemical initial and lateral boundary conditions (IC/BCs) on the air quality simulation using a chemical downscaling technique. The model domain was configured over the East Asian region and anthropogenic MICS-Asia 2010 emissions and biogenic MEGAN-2 emissions were applied with RACM gaseous chemistry and MADE/SORGAM aerosol mechanism. Two simulations were conducted for a 30-days period on April 2010 with chemical IC/BCs from the WRF-Chem default chemical species profiles (‘WRF experiment’) and the MOZART-4 (Model for OZone And Related chemical Tracers version 4) (‘WRF_MOZART experiment’), respectively. The WRF_MOZART experiment has showed a better performance to predict near-surface CO, NO₂, SO₂, and O₃ mixing ratios at 7 major Korean cities than the WRF experiment, showing lower mean bias error (MBE) and higher index of agreement (IOA). The quantitative impacts of the chemical IC/BCs have depended on atmospheric residence time of the pollutants as well as the relative difference of chemical mixing ratios between the WRF and WRF_MOZART experiments at the lateral boundaries. Specifically, the WRF_MOZART experiment has reduced MBE in CO and O₃ mixing ratios by 60~80 ppb and 5~10 ppb over South Korea than those in the WRF-Chem default simulation, while it has a marginal impact on NO₂ and SO₂ mixing ratios. Without using MOZART-4 chemical IC, the WRF simulation has required approximately 6-days chemical spin-up time for the East Asian model domain. Overall, the results indicate that realistic chemical IC/BCs are prerequisite in the WRF-Chem simulation to improve a forecast skill of local air quality over South Korea, even in case the model domain is sufficiently large to represent anthropogenic emissions from China, Japan, and South Korea.

구름과 에어로졸 고찰

염성수(Yum, Seong Soo),김병곤(Kim, Byung Gon),김상우(Kim, Sang Woo),장임석(Chang, Lim Seok),김승범(Kim, Seong Bum) 한국기후변화학회 2011 한국기후변화학회지 Vol.2 No.4

2008년 북경 올림픽이 한반도 대기질에 미치는 영향

송형도 ( Hyung Do Song ),최진수 ( Jin Soo Choi ),홍성철 ( Sung Chel Hong ),장임석 ( Lim Seok Chang ),김정수 ( Jung Soo Kim ),이석조 ( Suk Jo Lee ) 한국환경과학회 2009 한국환경과학회지 Vol.18 No.6

한 · 중 · 일 PM<SUB>10</SUB> 국가 배경농도 최근 경향 분석

양금희(Geum-Hee Yang),이종재(Jong-Jae Lee),유영숙(Young-Sook Lyu),장임석(Lim-Seok Chang),임재현(Jae Hyun Lim),이동원(Dong-Won Lee),김상균(Sang-Kyun Kim),김철희(Cheol-Hee Kim) 한국대기환경학회 2016 한국대기환경학회지 Vol.32 No.4

항공관측 및 대기질 모델링을 활용한 장거리 이동물질 영향 연구

이성우(Sung-Woo Lee),최민혁(Min-Hyeok Choi),최진수(Jin-Su Choi),손정석(Jung-Suk Son),김성용(Sung-Yong Kim),장임석(Lim-Seok Chang),이성우(Sung-Woo Lee),김종춘(Jong-Chun Kim),반수진(Soo-Jin Ban),장성기(Seong-Ki Jang),황경철(Kyung-Chul 한국환경관리학회 2011 環境管理學會誌 Vol.17 No.3

This study was conducted as the Long-range Transboundary Air Pollutants (LTP) Project among Korea, Japan and China. The research aims to understand atmospheric environment in Northeast Asia as well as determine causes of air pollution in the region. It ultimately wants to provide scientific data for establishing air pollution reduction measures. To this end, several activities were performed including aircraft measurement, upper and synoptic atmosphere analysis, and modeling analysis. Aircraft measurement was carried out in 2010 during two intensive measurement periods in vertical and zonal paths. The first measurement period was between May 15~25 for 7 times, and the second one was November 15~22 for 8 times. The highest pollutants concentration was observed in 20 May 2010. On this day, the mean concentration of SO₂ was 5.56 ppb, CO was 0.23 ppm, O3 was 9.47ppb, NOx was 4.01 ppb, PAN was 1.37 ppb, and particle number was 194.968 N/㎤, higher than the other measurement days. The modeling result during the aircraft measurement was quite reliable as it was performed based on the 2006 INTEX-B emission data. In addition, high concentration events and tracts of air pollutant movement were well simulated in the model. But the modeling result also requires some further improvement as it tends to underestimate their absolute values.

논에서 이탈리안 라이그라스 품종별 파종시기가 월동 및 건물수량에 미치는 영향

김맹중(Meing Jooung Kim),최기준(Ki Jun Choi),김종근(Jong Geun Kim),서성(Sung Seo),윤세형(Sei Hyung Yoon),임영철(Young Chul Lim),임석기(Seok Ki Im),권응기(Eung Gi Kwon),장선식(Sun Sik Chang),김형철(Hyeong Cheol Kim),김태일(Tae Il Kim 韓國草地學會 2009 한국초지조사료학회지 Vol.29 No.4

논에서 내한성 이탈리안 라이그라스의 조중 만생 숙기별 Kospeed, Kowinmaster, Hwasan 101호 3품종을 파종시기별로 9월 30일부터 5일간격으로 10월 20일까지 5처리 파종하여 이듬해 5월 17일에 수확하였고 단위면적당 입모수, 월동률 및 건물수량에 미치는 시험을 2003년부터 2005년까지 수원에서 수행하였다. 논에서 이탈리안 라이그라스 조생종(Kospeed)의 출수기는 5월 7일에서 5월 13일이며 파종일이 늦으면 출수일도 늦어졌다. 또한 조생품종 이탈리안 라이그라스는 개화최성기에 수확할 수 있어 건물수량이 높고 모내기를 적기에 할 수 있었다. 중생종(Kowinmaster)은 5월 16일에 출수하였고, 만생종(Hwasan 101)은 생육시기가 늦어 출수 전에 수확하여 모내기를 5월 20일에 마쳤다. 중부지방에서 적기 모내기를 위해 5월 17일 수확한 건물수량은 9월 30일에 파종한 시험구의 조생종 Kospeed는 7,909 ㎏/㏊이며, 중생종 Kowinmaster 6,398 ㎏/㏊, 만생종 Hwasan 101호 5,204 ㎏/㏊이었다. 건물수량이 높은 조생종(Kospeed)의 논에서 적정 파종시기는 9월 30월에서 10월 5일까지이며 중 만생종은 파종시기가 빨라도 조생종보다 건물수량이 감소하였다. 파종시기에서 9월 하순에서 10월 5일까지는 건물수량이 차이가 없었으나 그 이후는 월동률도 급격히 떨어져지고 건물수량도 감소하였다. 또한 중 만생종은 숙기가 늦어 수분함량이 많아 사일리지 품질에도 영향을 미칠 것으로 판단된다. 따라서 중부지방에서 내한성 이탈리안 라이그라스의 논 재배는 조생종 품종으로 10월 5일 이전에 파종해야 건물수량을 높일 수 있을 것으로 판단한다. This experiment was carried out to investigate the effect of cultivar and seeding date on the winter survival rate, quality and DM yield of Italian ryegrass on paddy field for three years in Suwon. Seeding started from 30th Sep. 2003. at intervals of five days and finished 20th Oct. New varieties of Italian ryegrass used in this experiment were “Kospeed”, “Kowinmaster” and “Hwasan 101”. The winter survival average rate of 5th Oct. seeding plot was 89.8% and it decreased with delayed seeding date. The heading date of “Kospeed” was 7th~13rd May, “Kowinmaster” was 16th May, but “Hwasan 101 ho” didn’t show heading until 17th May. Dry matter (DM) yields of 30th Sep. seeding plot were Kospeed 7,909 ㎏/㏊, Kowinmaster 6,398 ㎏/㏊ and Hwasan 101 ho 5,204 ㎏/㏊. DM yield was decreased with delayed seeding date. Total digestible nutrient (TDN) yield was also decreased with delayed seeding date. Crude protein (CP) content was the highest in Kospeed. seeding plot as 18.3% and in vitro dry matter digestibility (IVDMD) was not showed significant difference among seeding dates.