Electrical signature of the October 2013 very severe cyclonic storm Phailin

Abstract

In this study we examine first of its kind from Indian sub-continent which concentrates the electrical signatures of lightning discharges associated with a very severe cyclonic storm (VSCS). Phailin cyclone during 8–14 October 2013 has been selected for the study. We have primarily used ground-based GLD360 network lightning data to understand the distribution, polarity and radiated peak current of lightning discharge associated with the inner core (~100 km radius) of Phailin. In the initial development stage of Phailin as a deep depression on 8–9 October, there were very few lightning discharged (>50) in the inner core, but when Phailin developed into a VSCS on 10 October, ~2300 lightning discharges were recorded in inner core. There was near-even distribution of positive cloud to ground and negative cloud to ground discharges in the core, and with strong opposite peak currents of ±150 kA prior to the cyclone landfall. The observations show that monitoring of lightning discharges in eye of the cyclone is helpful in tracking its intensity changes and hence can serve as early warning systems.