https://repository.kopri.re.kr/handle/201206/15874 2026-04-06T10:04:37Z 2026-04-06T10:04:37Z Oh, Seungmee Kim, Yong Pyo Park, Ki-Tae Seo, Min Ju Park, Jiyeon Yoon, Young Jun Jung, Chang Hoon Lee, Ji Yi https://repository.kopri.re.kr/handle/201206/16549 2026-02-04T06:05:00Z 2025-02-01T00:00:00Z

Title: Spatiotemporal distribution of marine aerosols and gaseous species over the North Pacific Ocean Authors: Oh, Seungmee; Kim, Yong Pyo; Park, Ki-Tae; Seo, Min Ju; Park, Jiyeon; Yoon, Young Jun; Jung, Chang Hoon; Lee, Ji Yi Abstract: Observational studies of marine aerosols are essential for understanding the global aerosol budget and its environmental impacts. This study presents simultaneous in-situ measurements of major ionic components (Cl , NO3, SO4 2 , NH4+, K+, Ca2+, Na+, and Mg2+) in aerosols and gaseous species (HCl, HNO3, HONO, SO2, and NH3) over the North Pacific Ocean from July 4 to 15 and September 19 to October 3, 2022. Using high temporal resolution instruments aboard the Republic of Korea’s icebreaker research vessel Araon, this study aimed to (1) report the spatial and temporal distributions of aerosols and gaseous species, (2) estimate the source contribu tions of continental anthropogenic pollutants, and (3) assess the influence of aerosol chemical composition and gaseous species on aerosol acidity and water content. Our results revealed a significant decline in anthropogenic contributions, from 72.4 ±11.2 % in the Yellow Sea and East Sea to 32.0 ±10.8 % in the remote Pacific, accompanied by an increase in natural aerosols from 27.6 ±11.2 % to 68.0 ±10.8 %. Elevated concentrations of ammonia (NH3) and nitrous acid (HONO) were observed in the remote ocean, likely associated with the marine environment and biological activities. This increase in NH3, along with a decrease in sulfate concentrations, contributed to the formation of more alkaline aerosols in the remote ocean. Despite the limited availability of previous studies for direct comparisons, our findings align with observed trends and highlight the unique physicochemical properties of marine aerosols. These results enhance our understanding for the interactions between continental pollutants and marine environments, emphasizing the distinct characteristics of marine aerosols and their potential role in modifying atmospheric processes and influencing climate change.

2025-02-01T00:00:00Z Kang, Hyo Jin Jung, Chang Hoon Lee, Bang Yong Krejci, Radovan Heslin-Rees, Dominic Aas, Wenche Yoon, Young Jun https://repository.kopri.re.kr/handle/201206/16053 2025-08-22T07:43:11Z 2025-01-01T00:00:00Z

Title: Aerosol hygroscopicity influenced by seasonal chemical composition variations in the Arctic region Authors: Kang, Hyo Jin; Jung, Chang Hoon; Lee, Bang Yong; Krejci, Radovan; Heslin-Rees, Dominic; Aas, Wenche; Yoon, Young Jun Abstract: In this study, we quantified aerosol hygroscopicity parameter using aerosol microphysical observation data (xphy), analyzing monthly and seasonal trends in xphy by correlating it with aerosol chemical composition over 6 years from April 2007 to March 2013 at the Zeppelin Observatory in Svalbard, Arctic region. The monthly mean xphy value exhibited distinct seasonal variations, remaining high from winter to spring, reaching its minimum in summer, followed by an increase in fall, and maintaining elevated levels in winter. To verify the reliability of xphy, we employed the hygroscopicity parameter calculated from chemical composition data (xchem). The chemical composition and PM2.5 mass concentration required to calculate xchem was obtained through Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2) reanalysis data and the calculation of xchem assumed that Arctic aerosols comprise only five species: black carbon (BC), organic matter (OM), ammonium sulfate (AS), sea salt aerosol less than a diameter of 2.5 mu m (SSA2.5), and dust aerosol less than a diameter of 2.5 mu m (Dust2.5). The xchem had no distinct correlation but had a similar seasonal trend compared to xphy. The xchem value followed a trend of SSA2.5 and was much higher by a factor of 1.6 +/- 0.3 than xphy on average, due to a large proportion of SSA2.5 mass concentration in MERRA-2 reanalysis data. This may be due to the overestimation of sea salt aerosols in MERRA-2 reanalysis. The relationship between monthly mean xphy and the chemical composition used to calculate xchem was also analyzed. The elevated xphy from October to February resulted from the dominant influence of SSA2.5, while the maximum xphy in March was concurrently influenced by increasing AS and Dust2.5 associated with long-range transport from mid-latitude regions during Arctic haze periods and by SSA mass concentration obtained from in-situ sampling, which remained high from the preceding winter. The relatively low xphy from April to September can be attributed to low SSA2.5 and the dominance of organic compounds in the Arctic summer. Either natural sources such as those of marine and terrestrial biogenic origin or long-range-transported aerosols may contribute to the increase in organic aerosols in summer, potentially influencing the reduction in xphy of atmospheric aerosols. To our knowledge, this is the first study to analyze the monthly and seasonal variation of aerosol hygroscopicity calculated using long-term microphysical data, and this result provides evidence that changes in monthly and seasonal hygroscopicity variation occur depending on chemical composition.

2025-01-01T00:00:00Z Park, Ki-Tae Yoon, Young Jun Lee, Kitack https://repository.kopri.re.kr/handle/201206/16041 2025-08-22T06:07:26Z 2025-01-01T00:00:00Z

Title: Quantifying dimethylsulfoniopropionate lyase activity in marine environments using selected ion flow tube mass spectrometry Authors: Park, Ki-Tae; Yoon, Young Jun; Lee, Kitack Abstract: The global sulfur cycle is largely influenced by the production of dimethyl sulfide (DMS), which is primarily generated through the enzymatic cleavage of algal dimethylsulfoniopropionate (DMSP). This study presents an efficient and simplified method for analyzing DMSP lyase activity (DLA) by measuring the conversion efficiency of DMSP to DMS using selected ion flow tube mass spectrometry (SIFT-MS) coupled with a dissolved gas extraction device. Unlike conventional methods, which involve multiple steps such as trapping, desorption, and chromatographic separation, the proposed method consists of two streamlined steps: (1) Introduction of excess DMSP substrate into the sample vial, followed by continuous measurement of DMS evolution via SIFT-MS; (2) recording the DMS response at 3-s intervals and calculating the DMS production rate by dividing the integrated DMS mass over time intervals. The high-frequency detection of trace-level DMS enhances the accuracy of release rate measurements and aids in optimizing the DMSP substrate concentration. The performance of the proposed method was evaluated using cultured phytoplankton and natural seawater samples, achieving an analytical precision less than 10 % and a total analysis time of under 10 min, substantially faster than traditional gas chromatography-based techniques. This method provides a robust tool for investigating the dynamics of DMSrelated processes in marine environments.

2025-01-01T00:00:00Z Oh, Seungmee Kim, Yong Pyo Park, Ki-Tae Seo, Min Ju Park, Jiyeon Yoon, Young Jun Yoon, Young Jun Lee, Ji Yi https://repository.kopri.re.kr/handle/201206/16029 2025-08-22T03:07:46Z 2025-01-01T00:00:00Z

Title: Spatiotemporal distribution of marine aerosols and gaseous species over the North Pacific Ocean Authors: Oh, Seungmee; Kim, Yong Pyo; Park, Ki-Tae; Seo, Min Ju; Park, Jiyeon; Yoon, Young Jun; Yoon, Young Jun; Lee, Ji Yi Abstract: Observational studies of marine aerosols are essential for understanding the global aerosol budget and its environmental impacts. This study presents simultaneous in-situ measurements of major ionic components (Cl？, NO3？, SO42？, NH4+, K+, Ca2+, Na+, and Mg2+) in aerosols and gaseous species (HCl, HNO3, HONO, SO2, and NH3) over the North Pacific Ocean from July 4 to 15 and September 19 to October 3, 2022. Using high temporal resolution instruments aboard the Republic of Korea's icebreaker research vessel Araon, this study aimed to (1) report the spatial and temporal distributions of aerosols and gaseous species, (2) estimate the source contributions of continental anthropogenic pollutants, and (3) assess the influence of aerosol chemical composition and gaseous species on aerosol acidity and water content. Our results revealed a significant decline in anthropogenic contributions, from 72.4 ± 11.2 % in the Yellow Sea and East Sea to 32.0 ± 10.8 % in the remote Pacific, accompanied by an increase in natural aerosols from 27.6 ± 11.2 % to 68.0 ± 10.8 %. Elevated concentrations of ammonia (NH3) and nitrous acid (HONO) were observed in the remote ocean, likely associated with the marine environment and biological activities. This increase in NH3, along with a decrease in sulfate concentrations, contributed to the formation of more alkaline aerosols in the remote ocean. Despite the limited availability of previous studies for direct comparisons, our findings align with observed trends and highlight the unique physicochemical properties of marine aerosols. These results enhance our understanding for the interactions between continental pollutants and marine environments, emphasizing the distinct characteristics of marine aerosols and their potential role in modifying atmospheric processes and influencing climate change.

2025-01-01T00:00:00Z