Dual-frequency profiler study of hydrometeor fall speeds in tropical deep convection Journal Article uri icon

Overview

abstract

  • ; This study investigates hydrometeor fall speeds using a dual-frequency profiling radar operating during the 2005–2006 monsoon season near Darwin, Australia. Our focus is on tropical deep convection where the observations provide a new perspective on hydrometeor fall speeds within and near intense drafts having mixed-phase media. The techniques we employ avoid undue assumptions on the air motion or media distributions, offering a convenient path to estimate bulk radar reflectivity(; Z; )-weighted hydrometeor fall speed (; V; t; ). While these mixed-phase media estimates are not specific to size or density, they may be replicated by models and are practical for radar-based retrievals that necessitate; V; t; assumptions. Tests performed under rain and snow conditions show comparable performance to disdrometer and other references. The standard deviation of residuals for rain and snow relationships are ≅1 and ≅0.4 m s; −1; , respectively. In convective core regions aloft, Darwin observations align with existing graupel; V; t; -; Z; treatments, however mixed-phase media typically falls faster (>1–2 m s; −1; ) for; Z; <35 dBZ than prior relationships. Breakdowns suggest that Active and Break monsoon conditions favor a similar; V; t; -; Z; behavior in strong cores. However, Break conditions – those more favorable to intense daytime tropical convection – potentially indicate the presence of additional lofted liquid or melting media mixed in volumes at convective core peripheries; Z; <35 dBZ. Break events also show higher variability in; V; t; -; Z; pairs, with select samples having; V; t; faster than rain for a given; Z; that argues for partially-melted graupel coupled with size-sorting.;

publication date

  • October 2, 2026

Date in CU Experts

  • October 2, 2026 1:39 AM

Full Author List

  • Giangrande SE; Williams CR; Protat A

author count

  • 3

Other Profiles

Electronic International Standard Serial Number (EISSN)

  • 1867-8548

Additional Document Info

start page

  • 6251

end page

  • 6265

volume

  • 19

issue

  • 19