TY - JOUR
T1 - Regional variability in black carbon and carbon monoxide ratio from long-term observations over East Asia
T2 - Assessment of representativeness for black carbon (BC) and carbon monoxide (CO) emission inventories
AU - Choi, Yongjoo
AU - Kanaya, Yugo
AU - Park, Seung Myung
AU - Matsuki, Atsushi
AU - Sadanaga, Yasuhiro
AU - Kim, Sang Woo
AU - Uno, Itsushi
AU - Pan, Xiaole
AU - Lee, Meehye
AU - Kim, Hyunjae
AU - Hee Jung, Dong
N1 - Funding Information:
Financial support. This research has been supported by the Environment Research and Technology Development Fund of the Ministry of the Environment, Japan (grant no. 2-1803).
Publisher Copyright:
© Author(s) 2020.
PY - 2020/1/3
Y1 - 2020/1/3
N2 - The black carbon (BC) and carbon monoxide (CO) emission ratios were estimated and compiled from longterm, harmonized observations of the ΔBC/ΔCO ratios under conditions unaffected by wet deposition at four sites in East Asia, including two sites in South Korea (Baengnyeong and Gosan) and two sites in Japan (Noto and Fukuoka). Extended spatio-temporal coverage enabled estimation of the full seasonality and elucidation of the emission ratio in North Korea for the first time. The estimated ratios were used to validate the Regional Emission inventory in ASia (REAS) version 2.1 based on six study domains ("East China", "North China", "Northeast China", South Korea, North Korea, and Japan). We found that the ΔBC/ΔCO ratios from four sites converged into a narrow range (6.2-7.9 ngm-3 ppb-1), suggesting consistency in the results from independent observations and similarity in source profiles over the regions. The BC/CO ratios from the REAS emission inventory (7.7 ngm-3 ppb-1 for East China - 23.2 ngm-3 ppb-1 for South Korea) were overestimated by factors of 1.1 for East China to 3.0 for South Korea, whereas the ratio for North Korea (3.7 ngm-3 ppb-1 from REAS) was underestimated by a factor of 2.0, most likely due to inaccurate emissions from the road transportation sector. Seasonal variation in the BC/CO ratio from REAS was found to be the highest in winter (China and North Korea) or summer (South Korea and Japan), whereas the measured ΔBC/ΔCO ratio was the highest in spring in all source regions, indicating the need for further characterization of the seasonality when creating a bottom-up emission inventory. At levels of administrative districts, overestimation in Seoul, the southwestern regions of South Korea, and Northeast China was noticeable, and underestimation was mainly observed in the western regions in North Korea, including Pyongyang. These diagnoses are useful for identifying regions where revisions in the inventory are necessary, providing guidance for the refinement of BC and CO emission rate estimates over East Asia.
AB - The black carbon (BC) and carbon monoxide (CO) emission ratios were estimated and compiled from longterm, harmonized observations of the ΔBC/ΔCO ratios under conditions unaffected by wet deposition at four sites in East Asia, including two sites in South Korea (Baengnyeong and Gosan) and two sites in Japan (Noto and Fukuoka). Extended spatio-temporal coverage enabled estimation of the full seasonality and elucidation of the emission ratio in North Korea for the first time. The estimated ratios were used to validate the Regional Emission inventory in ASia (REAS) version 2.1 based on six study domains ("East China", "North China", "Northeast China", South Korea, North Korea, and Japan). We found that the ΔBC/ΔCO ratios from four sites converged into a narrow range (6.2-7.9 ngm-3 ppb-1), suggesting consistency in the results from independent observations and similarity in source profiles over the regions. The BC/CO ratios from the REAS emission inventory (7.7 ngm-3 ppb-1 for East China - 23.2 ngm-3 ppb-1 for South Korea) were overestimated by factors of 1.1 for East China to 3.0 for South Korea, whereas the ratio for North Korea (3.7 ngm-3 ppb-1 from REAS) was underestimated by a factor of 2.0, most likely due to inaccurate emissions from the road transportation sector. Seasonal variation in the BC/CO ratio from REAS was found to be the highest in winter (China and North Korea) or summer (South Korea and Japan), whereas the measured ΔBC/ΔCO ratio was the highest in spring in all source regions, indicating the need for further characterization of the seasonality when creating a bottom-up emission inventory. At levels of administrative districts, overestimation in Seoul, the southwestern regions of South Korea, and Northeast China was noticeable, and underestimation was mainly observed in the western regions in North Korea, including Pyongyang. These diagnoses are useful for identifying regions where revisions in the inventory are necessary, providing guidance for the refinement of BC and CO emission rate estimates over East Asia.
UR - http://www.scopus.com/inward/record.url?scp=85077604413&partnerID=8YFLogxK
U2 - 10.5194/acp-20-83-2020
DO - 10.5194/acp-20-83-2020
M3 - Article
AN - SCOPUS:85077604413
SN - 1680-7316
VL - 20
SP - 83
EP - 98
JO - Atmospheric Chemistry and Physics
JF - Atmospheric Chemistry and Physics
IS - 1
ER -