Influence of aerosols on lightning activities in central eastern parts of China

Abstract

Abstract Time series data of lightning flash rates, aerosol optical depth (AOD), surface relative humidity, potential temperature, and convective available potential energy (CAPE) for 14 consecutive summers (2001–2014) over central eastern parts of China (32.5°–40°N, 100°–120°E) have been analyzed to investigate the impact of aerosol on the lightning flash rate. The Pearson correlation and the partial correlation are used to study the linear correlations between the lightning flash rate and AOD, potential temperature, surface relative humidity, and CAPE. The results show that the lightning flash rate is positively correlated ( r = .64) with AOD under relatively clean conditions (AOD < 1.0), which may result from aerosol microphysical effect. In the situation of high aerosol concentration (AOD > 1.0), the correlation between AOD and lightning flash rate is not obvious ( r = −.06), which may be due to the radiation effect of aerosol and the decrease of the number of large ice particles caused by excessive aerosol concentration. CAPE and surface relative humidity are both positively correlated with the lightning flash rates under relatively clean (AOD < 1.0) and relatively polluted (AOD > 1.0) conditions. Potential temperature is moderate positively correlated with the lightning flash rate under relatively clean conditions ( r = .51, AOD < 1.0) but shows no significant linear relationship under relatively polluted conditions ( r = .07, AOD > 1.0).