Analyzing the Characteristics of Cloud Condensation Nuclei (CCN) in Hebei, China Using Multi-Year Observation and Reanalysis Data

The study of the characteristics and variations cloud condensation nuclei (CCN) plays an important role in understanding effects aerosol–cloud interactions. This paper selected observation data a city region Shijiazhuang North China from 2005 to 2007, along with corresponding MERRA-2 ERA5 data, analyze CCN, sort factors affecting diurnal variation CCN number concentration (NCCN) according their importance, build relationship between NCCN supersaturation (SS) heavily polluted region. results show that there was bimodal distribution daily time series for Shijiazhuang, China. By calculating correlation pollutants observed winter we identified dominant factor peaks is SO2 morning but NO2 evening. We also ranked by using reanalysis found greatest impact summer, atmospheric stability winter. Finally, determined SS Twomey formula (NCCN = cSSk) reasonable value range (i.e., 0.5~0.7) parameter East Specifically, it more be 0.5 summer 0.7