Effect of meteorological parameters and environmental pollution on thunderstorm and lightning activity over an urban metropolis of India

The purpose of this study is to understand the effect of meteorological parameters and environmental pollution on thunderstorm and lightning activity over Kolkata (22.65 degrees N,88.45 degrees E), India during the pre monsoon season (April-May). The aerosol optical depth, cloud top temperature and lightning flash rate are analyzed with 2004-2010 observations. The convective available potential energy (CAPE) and convective condensation level (CCL) are utilized to view the role of convective energy and level of cloud base in thunderstorm and lightning activities. The suspended particulate matter (SPM), sulfur oxides (SOx) and nitrogen oxides (NOx) are also considered for a precise understanding of the effects of all these parameters on thunderstorms and lightning activity. High variability in convective energy persists over Kolkata during the pre monsoon season. It is observed that high CAPE and lower CCL leads to maximum wind speed with thunderstorms. Irrespective of CCL heights the average concentration of SPM is observed to be high for increased lightning flash rate. It is revealed that increased surface pollution in a near storm environment can increase the lightning flash rate during thunderstorms. The result also shows that the enhanced lightning activity intensifies the production of tropospheric NO2. (C) 2013 Elsevier Ltd. All rights reserved.