Impact of electrified and non-electrified clouds on the inter-seasonal characteristics of surface-based precipitation

摘要

A multi-sensor analysis of the characteristics of electrified and non-electrified clouds along with their impact on the surface-based raindrop size distribution (DSD) during the inter-seasonal phases of Indian summer monsoon over a heavy precipitation region of Western Ghat (WG) has been highlighted in the present paper. The analysis reveals that during the pre-monsoon (monsoon) months, raindrops of larger diameter dominate the rainfall evolving from the non-electrified (electrified) clouds compared to the rainfall evolving from the electrified (non-electrified) ones. The complex relationship of the convective rainfall with highly charged electrified clouds forces the smaller drops aloft and thereby allowing the larger drops to precipitate locally during the pre-monsoon season. While for the monsoon months, as most of the rainfall originates from the deep clouds, the chances of drops to break-up/evaporate is comparatively less for the precipitation evolving from electrified clouds with charged droplets with respect to the non-electrified ones. Hence, drops of larger diameter dominate the monsoon rainfall associated with lightning. Correspondingly, the paper also highlighted a case study of the changing morphology of the vertical structure of clouds and surface precipitation with the evolution of lightning during various stages of a typical rainfall event over the orographic region of WG.