资源环境科技发展态势分析平台

This study proposes a new estimation method for vertically integrated liquid water content (VIL) using radar reflectivity volume data and temperature sounding retrieved from the numerical weather model analysis. This method addresses uncertainty factors in conventional VIL estimation associated with the effects from the bright band (BB) and radar beam geometry near the radar site. The new VIL is then used for precipitation classification (convective/stratiform) and wind turbine clutter detection in the hope that the estimated VIL indicating vertical activities or development of precipitation systems will account for the two independent subjects together, in opposite ways. The non-precipitation radar echoes returned from wind turbines do not likely generate significant degree of VIL, compared to the one estimated from actual convective cells, which contain comparable reflectivity strength. We tested the proposed VIL estimation, precipitation classification, and wind turbine clutter detection methods using various Iowa cases and illustrated their successful application. We also performed a quantitative evaluation of precipitation classification using ground reference data from a dense rain gauge network over the Turkey River basin in Iowa. The evaluation results show improved performance for most non-convective event cases estimated by the stratiform estimator (Z = 200R(1.6)) because we applied the convective estimator (Z = 300R(1.4)) to all event cases without classification. In addition, we demonstrated the potential of the new classification to mitigate significant BB effects in quantitative precipitation estimation using a correction method based on the vertical profile of reflectivity.