Review on Climate Characteristics of Lightning Activity

Latest research results on the correlation between lightning activity and climate and climate change are reviewed. The results indicate that global lightning can be measured by using satellite optical sensor,Schumann resonances, and the time-of-arrival (TOA) techniques at very low frequency. It is observed that high lightning density areas mainly lie in seaboards, mountains, high frequency mesoscale cyclone areas,and convergent regions such as the intertropical convergence zone. Eighty-eight percent of global lightning discharges occurs in continent island and seaboard areas. The three regions hit most frequently by lightning are Congo in equatorial Africa, South America, and South and Southeast Asia. A lot of studies reveal that the global lightning activity is directly related to the earth's climate and climate change. The global lightning activity responds positively to temperature changes on many time scales, such as diurnal, pentad,intraseasonal, semiannual, annual, ENSO, and decadal time scales. However, the sensitivity of lightning to temperature changes appears to diminish at longer time scales. Since lightning can be monitored easily and continuously, it becomes a useful and important parameter for monitoring climate change. The lightning discharge is a significant producing source of nitrogen oxides (NOx) in the atmosphere, which is closely associated with ozone production and the earth's radiation balance. There exists a robust positive correlation between lightning activity and upper tropospheric water vapor on short time scales. The effect of aerosol on thunderstorm and lightning is uncertain. More observations and investigations are needed to identify the coupling mechanism between lightning and climate change.