Ionospheric Responses to Very Severe Tropical Cyclones

In this study our aim is to find out the significant characteristics of ionospheric-tropospheric coupling during very severe cyclonic storms Lehar (2013) and Vayu (2019). We study the daily variation of average vertical total electron content (AVTEC) during the tropical cyclone(TC)s and compare it with the monthly mean of AVTEC variation. After the landfall of TC Lehar the AVTEC over a cyclone affected area Port Blair is dropped by 16 TECU (from 60 TECU to 44 TECU) whereas, during Vayu it is enhanced by 6 TECU (from 16 TECU to 22 TECU) over Yibal. The convective activity generated near the TCs inferred from the outgoing longwave radiation (OLR) can be the cause of the generation of Gravity waves which initiates ionospheric disturbances.