Effect of Atmospheric Aerosol on Lightning Activity Over North East India

Abstract

The observations of the lightning activity variation from 1998 to 2011 due to atmospheric aerosol effect over the North East India have been reported here. It has been observed that the lightning activity increases very rapidly in this region with a rate of 867 lightning flashes per year. Lightning activity over this region mainly occurs in two periods—March to June and August to October every year. As the higher lightning activity occurs during March to June months, i.e., mainly during the Monsoon season, correlation has been found between lightning activity and convective activity.  Good correlation has been observed with lightning upto the year 2009, after that lightning activity increases suddenly in the year 2010 and then again decreases. In further analysis, it is observed that the aerosol activity increases very significantly between 2009 and 2011 and may be the reason for increasing the lightning activity over this region in around 2010. 

Keywords:  Lightning , convective available potential energy, aerosol optical depth