In this study, we investigated the reasons for the increase and decrease in CAPSS emissions between Version 5(2015 ~ 2019) and Version 6(2016 ~ 2019). To do so, we studied the characteristics of CAPSS emissions in the port cities of Gunsan, Yeosu, and...
In this study, we investigated the reasons for the increase and decrease in CAPSS emissions between Version 5(2015 ~ 2019) and Version 6(2016 ~ 2019). To do so, we studied the characteristics of CAPSS emissions in the port cities of Gunsan, Yeosu, and Suyeong-gu, Busan, and the inland cities of Iksan and Jeonju.
First, Gunsan compared and analyzed commercial, residential, and industrial complex areas(air pollution characteristics) according to major pollution sources by considering the concentration and characteristics of major air pollutants using measurement network data and meteorological data by urban atmosphere region, and performed back trajectory analysis using the back trajectory model HYSPLIT-4 to analyze the cluster characteristics.
Second, we analyzed the differences and characteristics of CO, NOX, SOX, PM10, VOCS, and NH3 emissions by year using Existing-CAPSS existing emission data(Version 5) for 5 years (2015 ~ 2019) and Recalculated-CAPSS recalculated emission data(Version 6) for 4 years(2016 ~ 2019), and analyzed the differences in emission characteristics in neighboring regions(Iksan, Jeonju).
Third, Yeosu used the improved CAPSS emission data(Version 6) from 2016 to 2021 to calculate and analyze local emissions by substance(CO, NOX, SOX, PM10, VOCS, NH3) by source characteristics. We also compared and analyzed the impact of emissions in Gunsan and Yeosu, which have industrial complexes, with emissions in Suyeong-gu, Busan, which does not have industrial complexes.
Air pollutants in Gunsan(2017 ~ 2019) decreased with NO2(14.6 ← 11.7 ppb), SO2(4.5 ← 4.4 ppb), and PM10(45.3 ← 44.6 μg/m3), and increased with CO(470.9 → 477.8 ppb), O3(32.8 → 33.1 ppb), and PM2.5(25.7 → 26.0 μg/m3). And the monthly changes in air pollutants in Gunsan were highest in January to February for SO2, CO, and NO2(5.1 ~ 5.7 ppb, 602.8 ~ 593.9 ppb, 16.0 ~ 14.1 ppb), O3 in May to June(39.9 ~ 38.8 ppb), PM10 in March to May(53.4 ~ 49.7 μg/m3), and PM2.5 in January to March(29.9 ~ 36.9 μg/m3). The average values of all air pollutants were lower in July to August than in other months. PM10 and PM2.5 showed the highest concentrations in March to May due to yellow dust.
According to the analysis of seasonal changes in air pollutants in Gunsan, SO2 and NO2 are fall> winter> spring> summer, CO is winter> fall> spring> summer, O3 is spring> summer> winter> fall, and PM10 and PM2.5 are spring> winter> fall> summer.
In the local air quality characteristics of Gunsan and Iksan, SO2 and PM10 were higher in the industrial area of Gunsan(5.5 ppb, 46.7 μg/m3) and in the commercial area of Iksan 4.4 ppb, 52.0 μg/m3). In Gunsan, CO and PM2.5 were high in residential areas(461.7 ppb, 43.9 μg/m3), in Iksan, CO was high in industrial areas(544.3 ppb), and PM2.5 was high in commercial areas(34.0 μg/m3). O3 concentrations were high in industrial areas(Gunsan 34.5 ppb, Iksan 31.3 ppb), and NO2 was high in commercial areas(Gunsan 14.0 ppb, Iksan 17.1 ppb).
The cluster analysis using the inverse trajectory model HYSPLIT-4 categorized Gunsan into four clusters in 2017, six in 2018, and five in 2019, and Iksan into five clusters in 2017, six in 2018, and four in 2019.
As a result of comparing the emissions of Ex-CAPSS(Version 5) and Re-CAPSS(Version 6) in Gunsan, the emissions of Re-CAPSS by substance decreased by 39.76% for CO, 9.98% for PM10, 5.53% for VOCS, and 9.24% for NH3, and increased by 2.86% for Re-NOX and 1.97% for Re-SOX compared to the emissions of Ex-CAPSS by substance. The difference between the emission characteristics of Ex-CAPSS and Re-CAPSS emissions in Gunsan showed different differences in the emission characteristics of Re-CO and Re-PM10.
As a result of comparing the Ex-CAPSS emissions and Re-CAPSS emissions of Gunsan, Iksan, and Jeonju, Gunsan was found to have higher Ex, Re-NOX, SOX, and VOCS emissions than Iksan and Jeonju, while Iksan had higher Ex, Re-NH3 emissions and Jeonju had higher Ex, Re-PM10 emissions. And Gunsan showed different differences in Ex·Re-CO, Iksan showed different differences in Ex·Re-PM10, NH3, and Jeonju showed different differences in Ex·Re-NH3.
The reason for the high emissions of CO, NOX, SOX, VOCS, and NH3 in Yeosu is that the utilization rate of industrial and agricultural parks increased year by year during the study period. NOX and SOX showed a decreasing trend during the study period, while VOCS emissions increased. And the total emissions of CO, NH3, SOX, and VOCS were found to be high mainly in the production process, especially in the petrochemical, chemical, and chemical product manufacturing processes. This is because Yeosu has the second largest petrochemical production and petroleum consumption after Ulsan, and its industrial economic structure is thought to be influenced by the fact that the petroleum manufacturing industry is larger than the mining industry.
According to the results of the emission source characterization for each of the six air pollutants in Yeosu, CO was emitted from non-road transportation sources and production processes, PM10 was emitted from non-road transportation sources and fugitive dust, and NH3 was emitted from production processes. NOX was emitted from non-road transportation pollution sources and combustion in energy production, SOX was emitted from production processes and combustion in energy production, and VOCS emission sources were investigated as production processes.
When looking at the amount of air pollutant emissions in Yeosu, Gunsan, and Busan Suyeong-gu, Busan Suyeong-gu was found to be much lower than Yeosu and Gunsan. Since there is no industrial complex in Busan Suyeong-gu, the amount of emissions was found to be low, suggesting that the presence or absence of industrial complexes affects the amount of emissions.
When examining the characteristics and ratios of air pollutant emissions in Yeosu, Gunsan, and Suyeong-gu, Busan, Gunsan was found to have the highest VOCs emissions from the shipbuilding industry, while Yeosu was found to have the highest VOCs emissions from the petrochemical manufacturing and processing industry. Therefore, it is believed that investment in high-intensity VOCs control equipment is absolutely necessary to improve air quality in Gunsan and Yeosu.
For air quality concentrations in Yeosu, CO, NO2, SO2, and PM10 showed a decreasing trend in contrast to Gunsan and Busan Suyeong-gu, which is likely influenced by the geography of the area.
The difference between the increase and decrease in CAPSS emissions between Version 5 and Version 6 are attributed to the emissions impact of whether or not ship leisure sources are included in the non-road transportation sources.