Macro-and Microphysical Characteristics of Extreme Rainfall Producing-convective Clouds Observed by the Nanjing Dual-polarimetric Radar During the 2020-2022 Warm Seasons
WANG Ying
LUO Yali
LIU Xi
WU Chong
REN Fumin
Abstract：Despite global warming increases extreme precipitation frequency,the understanding of the macro-and microphysical characteristics of extreme precipitation-producing convective clouds in different regions remains incomplete.This study utilizes dual-polarization radar and rain gauges data(May-September 2020-2022)in the Nanjing area to compare three rainfall intensity-based Extreme Precipitation Features(EPFs)groups(ER1,ER2,ER3).Each group is further categorized into EPFs with intense,moderate and weak convection.It is found that,as the rainfall extremity increases,the horizontal extent of 40 dBZ region in EPFs increases,whereas 20 dBZ regions exhibit minimal changes.The proportion of intense convection EPFs rises from 11.4%to 25.4%,while the proportion of weak convection declines from 36.6%to 23.8%.The liquid and ice water contents in intense and moderate convection EPFs increase significantly with more extreme rainfall,while both mixed-and liquid-phase processes become more active.In EPFs with intense convection,liquid-phase processes are mainly dominated by size sorting and evaporation,while EPFs with weak convection are governed by coalescence.The raindrop size distributions resemble maritime-like convection,with characteristics between"maritime-like"and"continental-like"convection.The peak values of concentration and droplets size belong to"maritime-like"convection,with raindrop size distributions featuring a mean size large than"maritime-like"droplets and a concentration much higher than"continental-like"raindrops.As the rainfall extremity increases,liquid-phase processes show a slightly decrease in raindrop coalescence and a slight increase in raindrop breakup.The average raindrops size and concentration of ER1 to ER3 exhibit minimal variation.
Keywords：extreme precipitationconvective intensityNanjing areadual-polarimetric radarmicrophysi-cal characteristics
Publication Date：2025-06-30
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：13( 427-439 )