Seasonal variation in aerosol chemistry drives new particle formation and CCN activity in a coastal city, China: insights from year-long online measurements in Fuzhou
Year-long continuous observations demonstrate seasonal impacts of aerosol chemistry on CCN activity in Fuzhou.
Key Points
This study examines how seasonal variations in aerosol chemistry influence new particle formation (NPF) and cloud condensation nuclei (CCN) activity in Fuzhou, China.
Continuous measurements of aerosol concentrations were conducted from June 2021 to May 2022.
A total of 46 NPF events were identified and analyzed for frequency, formation and growth rates.
The influence of temperature and relative humidity on NPF and CCN enhancement was assessed using XGBoost-SHAP.
NPF events showed seasonal variation with highest frequency in spring (27.17%) and lowest in summer (4.35%).
Average formation rate during spring was 5.56 cm-3s-1, while summer exhibited the highest growth rate at 11.68 nm h−1.
NPF significantly enhanced CCN in summer with an enhancement effect (E_NCCN) of 1.64, while spring had minimal CCN enhancement due to high condensation sink.