Assimilation of Reflectivity Data in a Convective-Scale, Cycled 3DVAR Framework with Hydrometeor Classification
Top Cited Papers
Open Access
- 1 March 2012
- journal article
- Published by American Meteorological Society in Journal of the Atmospheric Sciences
- Vol. 69 (3), 1054-1065
- https://doi.org/10.1175/jas-d-11-0162.1
Abstract
The impact of assimilating radar reflectivity and radial velocity data with an intermittent, cycled three-dimensional variational assimilation (3DVAR) system is explored using an idealized thunderstorm case and a real data case on 8 May 2003. A new forward operator for radar reflectivity is developed that uses a background temperature field provided by a numerical weather prediction model for automatic hydrometeor classification. Three types of experiments are performed on both the idealized and real data cases. The first experiment uses radial velocity data only, the second experiment uses both radial velocity and reflectivity data without hydrometeor classification, and the final experiment uses both radial velocity and reflectivity data with hydrometeor classification. All experiments advance the analysis state to the next observation time using a numerical model prediction, which is then used as the background for the next analysis. Results from both the idealized and real data cases show that, assimilating only radial velocity data, the model can reconstruct the supercell thunderstorm after several cycles, but the development of precipitation is delayed because of the well-known spinup problem. The spinup problem is reduced dramatically when assimilating reflectivity without hydrometeor classification. The analyses are further improved using the new reflectivity formulation with hydrometeor classification. This study represents a successful first effort in variational convective-scale data assimilation to partition hydrometeors using a background temperature field from a numerical weather prediction model.Keywords
This publication has 19 references indexed in Scilit:
- Ensemble Kalman Filter Assimilation of Radar Observations of the 8 May 2003 Oklahoma City Supercell: Influences of Reflectivity Observations on Storm-Scale AnalysesMonthly Weather Review, 2011
- 3DVAR and Cloud Analysis with WSR-88D Level-II Data for the Prediction of the Fort Worth, Texas, Tornadic Thunderstorms. Part II: Impact of Radial Velocity Analysis via 3DVARMonthly Weather Review, 2006
- 3DVAR and Cloud Analysis with WSR-88D Level-II Data for the Prediction of the Fort Worth, Texas, Tornadic Thunderstorms. Part I: Cloud Analysis and Its ImpactMonthly Weather Review, 2006
- Precipitation and Evolution Sensitivity in Simulated Deep Convective Storms: Comparisons between Liquid-Only and Simple Ice and Liquid Phase Microphysics*Monthly Weather Review, 2004
- A Three-Dimensional Variational Data Analysis Method with Recursive Filter for Doppler RadarsJournal of Atmospheric and Oceanic Technology, 2004
- A Variational Method for the Analysis of Three-Dimensional Wind Fields from Two Doppler RadarsMonthly Weather Review, 1999
- The Influence of Midtropospheric Dryness on Supercell Morphology and EvolutionMonthly Weather Review, 1998
- The Local Analysis and Prediction System (LAPS): Analyses of Clouds, Precipitation, and TemperatureWeather and Forecasting, 1996
- On the Environments of Tornadic and Nontornadic MesocyclonesWeather and Forecasting, 1994
- Terminal Velocity of Raindrops AloftJournal of Applied Meteorology, 1969