장기 관측을 통한 Black Carbon의 지역별 변동 특성 분석

다국어 초록 (Multilingual Abstract)

This study examined long-term trends, seasonal variability, diurnal patterns, and spatial heterogeneity of black carbon (BC) across three sites in South Korea (Yongin, Seoul, and Baengnyeongdo) based on extended observational datasets and ancillary information. To ensure inter-site comparability, BC absorption coefficients at Yongin were recalculated using the manufacturer-provided mass absorption coefficients (MAC = 6.6 m2 g-1). The mean BC absorption coefficient over the entire observation period was highest in Seoul (20.07 Mm-1), followed by Yongin (8.41 Mm-1) and Baengnyeongdo (4.56 Mm-1), indicating pronounced spatial gradients associated with differing emission environments and degrees of urbanization.
Annual mean absorption coefficients peaked in 2021 at 22.25 Mm-1 in Seoul and 5.78 Mm-1 in Baengnyeongdo, which were attributed to the combined effects of COVID-19 restriction relaxation, decreased precipitation, and enhanced contributions from high-emission source regions. In contrast, Yongin exhibited only a marginal increase (0.15 Mm-1) between 2020 and 2021, consistent with limited local emission sources and a slight reduction in adjacent traffic volume. Owing to the absence of local precipitation data for Yongin, precipitation records from nearby cities (Suwon and Icheon) were analyzed, revealing substantial decreases from 2020 to 2021 (e.g., Suwon: 1,635 to 1,084 mm; Icheon: 1,668 to 1,076 mm), which suggests that weakened wet scavenging likely contributed to the observed BC enhancement.
All three sites displayed pronounced seasonal cycles, with maximum absorption coefficients occurring in winter (Seoul: 24.2 Mm-1; Yongin: 17.29 Mm-1; Baengnyeongdo: 5.40 Mm-1) and minimum values in summer (17.0, 7.59, and 3.51 Mm-1, respectively). At Yongin, BC concentrations exhibited strong negative correlations with precipitation (r = -0.82) and temperature (r = -0.97), indicating the dominant influence of wet scavenging and boundary-layer development on BC variability. Furthermore, PSCF analysis demonstrated that wintertime high-BC episodes in Seoul and Baengnyeongdo were closely associated with air mass transport from eastern China and the Korean Peninsula, underscoring the significance of long-range transport processes.
This study provides robust multi-site, long-term observational evidence that BC concentrations do not necessarily decline consistently during periods of reduced anthropogenic activity, owing to the combined influences of meteorological conditions and regional transport. The findings enhance the understanding of BC variability across contrasting regional environments in South Korea and offer a valuable benchmark dataset for the evaluation of satellite-derived and reanalysis-based BC products.

목차 (Table of Contents)

• 제 1 장 서론 1
• 제 2 장 용인 지역 대기 중 BC 농도 특성 분석 및 일변화 패턴 군집 분석 6
• 제 1 절 서론 6
• 제 2 절 연구 방법 7
• 2.1. 측정 지역 및 측정 기간 7
• 2.2. 측정 장비 10
• 2.3. MERRA-2 재분석 데이터 14
• 2.4. 군집 분석 16
• 제 3 절 결과 및 토론 19
• 3.1. 전체 측정기간 농도 변화 19
• 3.1.1. 연도별 농도 변화 19
• 3.1.2. 월별 농도 변화 27
• 3.1.3. 일변화 및 요일별 농도 변화 32
• 3.2. 최적 군집 수 도출 40
• 3.3. 군집별 BC 농도 일변화 및 월별 비율 분포 43
• 3.4. 군집별 기상 인자 일변화 패턴 분석 50
• 3.4.1. Increase 51
• 3.4.2. Decrease 53
• 3.4.3. 8 AM peak 55
• 3.4.4. 10 AM peak 57
• 3.4.5. High 59
• 제 4 절 소결론 65
• 제 3 장 백령도 및 서울 기여도 분석 69
• 제 1 절 서론 69
• 제 2 절 연구 방법 70
• 2.1. 측정 지역 및 기간 70
• 2.2. 측정 장비 73
• 2.3. 역궤적 분석 75
• 제 3 절 결과 및 토론 77
• 3.1. 연도별 BC 흡수계수 추이 분석 77
• 3.2. 계절별 BC 흡수계수 추이 분석 84
• 3.3. 역궤적 분석 90
• 3.4. PSCF 분석 99
• 제 4 절 소결론 107
• 제 4 장 결론 110
• 부록 115
• 제 1 절 서론 115
• 제 2 절 측정 및 연구 방법 118
• 2.1. 측정 장소 및 기간 118
• 2.2. 측정원리 119
• 2.3. MAAP (multi-angle absorption photometer) 121
• 2.4. TAP (tricolor absorption photometer) 122
• 2.5. 확산 건조기 (diffusion drier) 126
• 제 3 절 결과 128
• 3.1. 장비 간 자료 보정을 통한 흡수계수 일치성 확보 연구 결과 128
• 3.1.1. βabs의 시계열 변화 128
• 3.1.2. βabs간의 상관관계 132
• 3.2. 확산 건조기 설치 유무에 따른 광흡수의 차이 분석 결과 134
• 3.2.1. 광흡수계수 (βabs)의 시계열 변화 134
• 3.2.2. 두 대의 TAP 간의 광흡수계수 (βabs)의 상관성 136
• 3.2.3. 확산 건조기 설치 유무에 따른 TAP와 MAAP 광흡수계수의 상관성 138
• 제 4 절 결론 140
• 참고 문헌 143