Kim, Jeongbeen Ha, Yoonkyeong Cho, Kyungil Lee, Soodong Jung, Jinsang Lee, Seung-Bok Lee, Ji Yi Song, Mijung Jang, Kyoung-Soon Lee, Kwangyul Ahn, Junyoung Kim, Changhyuk 2024-05-09T09:30:16Z 2024-05-09T09:30:16Z 2024-05-09 2024-05 0048-9697 https://pubs.kist.re.kr/handle/201004/149807 The hygroscopicity of PM2.5 particles plays an important role in PM2.5 haze in Northeast Asian countries by influencing particle growth and chemical composition. New particle formation (NPF) and atmospheric volatile organic compounds (VOCs) are factors that influence particle hygroscopicity. However, the lack of real-time hygroscopicity measurements has deterred the understanding of their effects on particle hygroscopicity. In this study, two intensive monitoring campaigns were conducted during the summer of 2021 and spring of 2022 using real-time aerosol instruments, including a humidified tandem differential mobility analyzer (HTDMA), in Seosan, Republic of Korea. The hygroscopicity parameter kappa was calculated from the real-time HTDMA measurement data (kappa Gf). The diurnal variations in kappa Gf exhibited strong inverse linear correlations with the total concentration of VOCs (CTVOC) during the two campaigns. The higher atmospheric CTVOC in summer increased the growth rate of the particle diameter from 10 to 40 nm (6 nm/h) compared with that in spring (2.7 nm/h), resulting in a faster change in kappa Gf for 40-nm particles in summer than in spring because of the increase in organic matter in the chemical compositions of particles. In addition, NPF events introduced additional tiny fresh particles into the atmosphere, which reduced the kappa Gf of 40-nm particles and increased the intensity of the less English Elsevier BV Effects of volatile organic compounds and new particle formation on real-time hygroscopicity of PM2.5 particles in Seosan, Republic of Korea Article 10.1016/j.scitotenv.2024.171516 1 Science of the Total Environment, v.924 Science of the Total Environment 924 N scie scopus 001209867700001 2-s2.0-85187639069 Environmental Sciences Environmental Sciences & Ecology Article SIZE-RESOLVED HYGROSCOPICITY CONDENSATION NUCLEI ACTIVITY RIVER DELTA REGION HR-TOF-AMS AEROSOL HYGROSCOPICITY MIXING STATE CHEMICAL-COMPOSITION SUBURBAN SITE AMBIENT AEROSOLS URBAN AEROSOL HTDMA Growth factor Hygroscopicity parameter Probability density function New particle formation Volatile organic compound