The measurement of ice nucleating particles at Tai'an city in East China

摘要

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 degrees C were 1.57 L-1 and 4.82 L-1 at RHw = 95% and RHw = 101%, respectively. At T = -25 degrees 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 mu m (< 0.5 mu m). 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.