The Sensitivity of Single Polarization Weather Radar Beam Blockage Correction to Variability in the Vertical Refractivity Gradient
Open Access
- 1 June 2003
- journal article
- Published by American Meteorological Society in Journal of Atmospheric and Oceanic Technology
- Vol. 20 (6), 845-855
- https://doi.org/10.1175/1520-0426(2003)020<0845:tsospw>2.0.co;2
Abstract
Radars operating in complex orographic areas usually suffer from partial or total beam blockage by surrounding targets at their lowest elevation scans. The need for radar quantitative precipitation estimates in such environments led to the development of beam blockage corrections. This paper aims at evaluating the performance of beam blockage corrections under different electromagnetic propagation conditions with particular interest in anaprop situations. Three years of radiosonde data collected at Barcelona, Spain, a typical Mediterranean coastal site, are used to characterize the behavior of the vertical refractivity gradient near a weather radar. Three different targets surrounding the radar have been chosen and used to evaluate the different beam shielding simulated under different propagation conditions. A simple interception function between the radar beam and the topography is proposed and used for the different targets and propagation conditions considered. Results show that beam blockage correction is generally robust, with departures of 1 dB from the standard propagation conditions correction less than 10% of the time. However, as the presence of extreme anaprop cases would lead to higher differences, the monitoring of the propagation conditions is suggested as a criteria to be considered, among others such as the analysis of the echo structure, as a quality control of the radar quantitative precipitation estimate.Keywords
This publication has 25 references indexed in Scilit:
- The operational weather radar of Fossalon di Grado (Gorizia, Italy): accuracy of reflectivity and differential reflectivity measurementsArchiv für Meteorologie, Geophysik und Bioklimatologie Serie A, 2002
- The 18 June 1997 Companion supercells: Multiparametric Doppler radar analysisArchiv für Meteorologie, Geophysik und Bioklimatologie Serie A, 2000
- Monitoring of Mesoscale Precipitation Systems in the Alps and the Northern Alpine Foreland by Radar and Rain GaugesArchiv für Meteorologie, Geophysik und Bioklimatologie Serie A, 2000
- Weather radar anaprop conditions at a mediterranean coastal sitePhysics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere, 2000
- Simulation of the Orographic Influence on Weather Radar Using a Geometric–Optics ApproachJournal of Atmospheric and Oceanic Technology, 1998
- The WSR-88D Rainfall AlgorithmWeather and Forecasting, 1998
- On the Extraction of Near-Surface Index of Refraction Using Radar Phase Measurements from Ground TargetsJournal of Atmospheric and Oceanic Technology, 1997
- Simulation of Radar Mountain Returns Using a Digitized Terrain ModelJournal of Atmospheric and Oceanic Technology, 1995
- Refractive index variance and its height distribution in different air massesRadio Science, 1977
- The accuracy of radar‐derived rainfall measurements in hilly terrainQuarterly Journal of the Royal Meteorological Society, 1974