Probing a post monsoon Mesoscale Convective System (MCS) and the generated Transient Luminous Events (TLEs) over Indian Region

Abstract

<p>A Mesoscale Convective System (MCS), consisting of three Super Cells<br>formed over South-east Indian, is assessed in detail with satellite and ground based<br>data-sets. The MCS under investigation generated a total of Ten (10) upward<br>electrical discharges (9 Sprites and 1 Gigantic Jet) commonly named as Transient<br>Luminous Events (TLEs). The TLEs were recorded from TLE observation station<br>located at Allahabad, India. The event occurred in the Post-Monsoon period of 2013<br>on October 7, during 15-23 UT hours. The MCS was spread over a region of 25000 sq.<br>Kilometers. A lowest cloud top temperature value of -84.7 0 C was observed in the<br>mature stage of the MCS, during 2130 UT hours, and the cloud top altitude was<br>reaching 17.6 km. The coldest cloud top region was covering an average area of<br>13000 sq. Km. The measured Convective Available Potential Energy (CAPE) value was<br>606.9 J/kg at 00 UT on 7 th October which dropped to 211 J/kg at 00 UT on 8 th<br>October. The mean lightning flash rate during the formation and maturity stages of<br>the MCS was around 46.03 min -1 . During the entire lifespan of the thunderstorm,<br>peak currents were found to be reaching ±400 kA. Such high electric currents,<br>extreme cold temperature and towering altitudes of the convective complexes show<br>how much a MCS is dynamically active and the TLEs which it produced are known to<br>electrically connect the lower atmosphere to the upper space environment.</p>