Vertical air motion retrieval from frequency-modulated continuous-wave-radar rain measurements

Abstract

Vertically pointing S-band Doppler radars measure reflectivity-velocity spectra, where the falling velocity of raindrops appears as a shift along the velocity axis. However, in convective rain scenarios, vertical air motion (VAM) introduces errors into radar-derived products, including drop size distribution, rain rate, and reflectivity factor. This study presents an enhanced forward-model retrieval method for estimating VAM velocity and retrieving these radar products. The forward estimator employs a parameterized Gamma distribution and an unknown VAM velocity to estimate the radar-observed aliased reflectivity-velocity profile. Building on previous work by the authors, this paper introduces a mathematical formulation for the aliased radar reflectivity along with first application of the method to a real measurement case from VORTEX-SE 2017 campaign.

This research is part of the project PID2021-126436OB-C21, funded by MInisterio de Ciencia, Innovación y Universidades (MICIU)/Agencia Estatal de Investigación (AEI)/10.13039/501100011033 and ERDF/EU, and part of the PRIN 2022 PNRR, project P20224AT3W funded by Ministero dell’Università e della Ricerca. The European Commission collaborated under project H2020 ATMO-ACCESS (GA-101008004).

Peer Reviewed

Postprint (author's final draft)