Wind Profiler Radars for understanding the influence of Convective Boundary Layer on precipitating clouds

摘要

The objective of this research is to elucidate tropical Continental boundary layer structures, evolution and their influence on precipitating cloud systems during different seasons over Gadanki, Southern India. We used WPR reflectivity, Doppler velocity and spectral width data in time versus altitude to characterize general behavior of convective boundary layer based on the morning and evening transition. From a wide variety of observed patterns, three categories are identified: (i) Decent, (ii) Ascent, and (ii) Inversion Layer. Results show the Ascent cases occur on relatively warm and moist days with strong turbulence and weak capping inversion [maximum occurrence in monsoon], decent days occur [pre-monsoon] on cooler and direr days with strong turbulence and temperature inversion and IL days occur [winter] on warm dry days with stronger turbulence and stronger and strong thermal inversion associated with multiple layers. WPR observational results also show that during Southwest monsoon mesoscale convective cloud systems are frequently prevalent than in Northeast winter monsoon over Southern India. Vertical rain structures, especially bright-band (BB) signatures are also analyzed to study possible relations between the BB structure and DSD.