An Intercomparison Study of NEXRAD Precipitation Estimates

摘要: Systematic biases in WSR-88D (Weather Surveillance Radar–1988 Doppler) hourly precipitation accumulation estimates are characterized from analyses of more than 1 year data and rain gage the southern plains. Biases examined three contexts: (1) that arise range-dependent sampling WSR-88D, (2) systematic differences radar rainfall two radars observing same area, (3) between rainfall. Range-dependent affect accumulations products over much area covered by WSR-88D. Significant underestimation occurs within 40 km range due to bias reflectivity observations at higher elevation angles used for estimation close radar. Bright band anomalous propagation (AP) lead overestimation intermediate range. Beyond 150 spring-summer beyond 100 winter-fall, is pronounced incomplete beam filling overshooting precipitation. Radar-radar intercomparison studies suggest calibration a significant problem some sites. Anomalous during clear-air conditions, major with previous National Weather Service network radars, has been largely eliminated processing. AP remains cases which returns embedded rain. Radar–rain indicate relative gages paired gage-radar estimates. Analyses spatial coverage heavy rainfall, however, illustrate fundamental advantages networks estimation.