Work

Spatial and temporal variation of raindrop size distribution in Great Britain

Year: 2025

Type: article

Abstract: Raindrop size distributions (DSDs) play a key role in revealing the underlying physical processes of rainfall. This study investigates the characteristics of the DSDs in Great Britain (GB) using data collected from eleven Thies laser precipitation monitors (LPMs) between 2017 and 2019. Around one million one-minute raindrop samples were fitted to a normalized gamma drop distribution model. This study examines the DSD characteristics from both temporal (seasons) and spatial (geography and topography) perspectives, considering different rain types (stratiform and convective) and rain rate clusters. The results indicate that the average mass-weighted mean diameter D m and the average normalized intercept parameter log 10 N w are influenced by geographical and atmospheric conditions. The D m tends to be lower and log 10 N w is higher in the western and hilly regions, with the opposite pattern observed over the eastern plain of GB. Both parameters are strongly correlated with rain rate. Compared to subtropical/tropical regions, stratiform rain in GB exhibits smaller D m and larger log 10 N w , while the characteristics of convective rain align with the maritime-like cluster. Significant differences in D m are observed between stratiform (0.78–1.00 mm) and convective (1.30–1.74 mm) rain, with both showing a significant negative linear correlation with log 10 N w . Moreover, extreme convective events show distinct seasonality, with larger D m and lower log 10 N w during the warm season. Furthermore, a bimodal distribution is observed for log 10 N w in light rain events over western and hilly regions, highlighting the complexity of microphysical processes associated with small raindrops. The characteristics of DSDs observed in this study provide valuable insights for future investigations into GB's precipitation formation and quantitative precipitation estimation using weather radar.

Source: Atmospheric Research

DOI: 10.1016/j.atmosres.2025.108699

Authors: Shan Jiang, Dawei Han, Rafael Rosolem, Merhala Thurai, Miguel A. Rico-Ramirez

Institutions: University of Bristol, Colorado State University

Language: English

Topic: Precipitation Measurement and Analysis

Subfield: Atmospheric Science

Field: Earth and Planetary Sciences

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,310

Funders: National Science Foundation, University of Bristol, China Scholarship Council