A Review of Uncertainty Sources on Weather Ground-Based Radar for Rainfall Estimation

Abstract

Efforts in hydrometeorology are concentrated on finding the causes of the ground based radar uncertainty sources for rainfall estimation recently. The error sources are interactions between radar with atmosphere and topography. Radar singly often covers systematic error whereas atmospheric and topographic errors are relevant to location and precipitation pattern. This article reviews uncertainty sources on weather ground-based radar in order to rainfall estimation that have been discussed in nine main categories includes; the range effects, radar signal attenuation, beam blockage, vertical air motion and precipitation drift, ground clutter, anomalous propagation, vertical variability of the precipitation system, variability of the Z-R relationship and bright band. Topographic errors such as ground clutter and beam blockage primarily can be eliminated by attentive in site selection. Atmospheric errors such as vertical air motion and precipitation drift can filter or eliminated by calibration methods. Systematic errors include radar signal attenuation and anomalous propagation is the result of structural changes in the radar waves in space. Thus, this review is explored the characteristics of uncertainty error resources and a comprehensive appraisal of experimental procedures is provided.

Rainfall Estimation Model in Seasonal Zone and Non-Seasonal Zone Regions Using Weather Radar Imagery Based on a Gradient Boosting Algorithm

“…For several reasons, radar and rain gauge quantitative measurements of precipitation can differ [67]; for example, the estimated rainfall measured by the weather radar may be rainfall that has not yet reached the ground's surface and is often far from the radar. The direction of wind movement could also affect the area of rainfall [68][69][70]. The product of the vertical reflectivity of the radar showed significant variability due to the growth of precipitation, evaporation, and the influence of the wind.…”

Precipitation Monitoring Using Commercial Microwave Links: Current Status, Challenges and Prospectives

“…Substitute Equation (3) into (5) to obtain an estimate R of the path-averaged rain rate, with the real path-averaged rain rate R shown by Equation (7):…”

“…However, the parameters of the Z-R relationship are highly sensitive to the raindrop size distribution (DSD) associated with precipitation types, geographical locations and climatic characteristics, which may cause large systematic biases [4]. Other uncertainty sources include ground clutter, beam blockage, bright bands and the vertical variability of the precipitation system [5]. As meteorological satellite technology matures, satellites can measure precipitation almost globally, which is especially important in areas where radar and rain gauges are not available [6].…”

A multi‐sensor evaluation of precipitation uncertainty for landslide‐triggering storm events

“…Since ground‐based radar is an indirect measurement of precipitation, its performance is dependent on skilful conversion of the radar signal to precipitation volume. Beam blockage and interference from buildings or even insects in the radar's path are another limitation (Bousquet & Smull, 2003 ; Fornasiero et al, 2004 ; Nikahd et al, 2016 ). Most ground‐based radars use multiple bands of radar and multiple polarities to compute the raindrop shape and size distributions used in the processing and limit the impact of known sources of error, which offers an advantage over other indirect techniques such as some of those incorporated into satellite‐based measurements (Chandrasekar et al, 2008 ).…”