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The composition of marine aerosol is quite complex, and its sources are diverse. Across the East China Sea (ECS) and the Yellow Sea (YS), multi-dimensional analysis of marine aerosols was conducted. The characteristics of carbonaceous aerosols and gaseous pollutants were explored through in situ ship-based observation, MERRA-2 reanalysis datasets and TROPOMI data from Sentinel-5P satellite. Black carbon (BC)'s average concentration is 1.35 ± 0.78 μg/m3, with high-value BC observed during the cruise. Through HYSPLIT trajectory analysis, sources of BC were from the northern Eurasian continent, the Shandong Peninsula, the ECS and Northwest Pacific Ocean (NWPO). The transport of marine sources like ship emissions cannot be ignored. According to the absorption Angstrom exponent (AAE), BC originates from biomass burning (BB) in the shortwave band (~370 nm) and from fossil fuel combustion in the longwave band (~660 nm). Organic carbon (OC), sulfate (SO42−) and BC report higher Angstrom exponent (AE) while dust and sea salt reveal lower AE, which can be utilized to classify the aerosols as being fine- or coarse-mode, respectively. OC has the highest AE (ECS: 1.98, YS: 2.01), indicating that anthropogenic activities could be a significant source. The process of biomass burning aerosol (BBA) mixed with sea salt could contribute to the decline in BBA's AE. Ship emissions may affect the distribution of tropospheric nitrogen dioxide (NO2) in the ECS, especially during the COVID-19 pandemic. Tropospheric NO2 over the YS has the highest value (up to 12 × 1015 molec/cm2). Stratospheric NO2 has a ladder-like distribution from north to south, and the variation gradient was lower than that in the troposphere. Carbon monoxide (CO) accumulates in the south and east of the ECS and the east of the YS, while the variation over the eastern YS is relatively frequent. Seas near the Korean Peninsula have extremely high CO concentration (up to 1.35 × 1017 molec/cm2). [ABSTRACT FROM AUTHOR]

In order to make up for deficiencies in the observations of ice nucleating particles (INP) over different regions of China, the concentration of INPs and aerosol number concentrations were measured at Tai'an city in Shandong province, East China using the newly built static vacuum water vapor diffusion chamber during June 2018. The INP concentration increases with the decrease of activation temperature and the increase of water relative humidity. The average concentrations of INP at T = −20 °C were 1.57 L−1 and 4.82 L−1 at RH w = 95% and RH w = 101%, respectively. At T = −25 °C the average concentrations were 11.5 L−1 and 37.5 L−1. A high (very low) correlation was found between INP concentration and the number concentration of aerosol particles having a size in the range of 0.5–5.0 μm (<0.5 μm). Further, it is evident that the key meteorological variables have significant influence on the INP concentration with strong winds resulting in higher concentration of larger particles, implies increase in the concentration of INP. At last, we compared the INP concentrations measured at Tai'an with different background regions of China, and found it is closest to that observed in the Nanjing city. • The concentration of INP and aerosols were measured in Tai'an city in Shandong province in eastern of China. • High correlation was found between INP concentration and the number concentration of aerosol particles lager than 0.5 μm. • Strong wind can lead to higher concentration of INP. • Different parameterizations were compared. [ABSTRACT FROM AUTHOR]