Study on identification of thunderstorm gale based on fuzzy-logical principle and Radar mosaic data

摘要

Based on Radar mosaic 3D data, automatic weather stations and disaster wind data, twenty cases of thunderstorm gale from 2008 to 2012 in North China are analyzed to develop a automated detection of thunderstorm gale with fuzzy logical based algorithm. The capability of the algorithm was examined. (1) In the algorithm, six main radar identification indices for ground gale detection are storm maximum reflectivity, storm maximum vertical integrated liquid water content, temporal variability of vertical integrated liquid water, storm speed, echo top and VIL density. Based on statistical analysis, the corresponding membership functions and weight coefficient were given. (2) In order to test the comprehensive identification of different types thunderstorm weather process, the echo is dived into three types of echo, such as massive echo, banding echo and floccus echo, the massive echo is triggered by strong storm monomer, including maximum echo strength, higher of echo top, bigger of VIL value and faster moving speed; Banding echo mainly contains the squall line and the bow echo, it's length is greater than the width; floccus echo generally refers to mixed echo both large area layer echo and the isolated massive echo. (3) All the gale is tested and analyzed, the results show: the gale of massive echo is caused nearby thunderstorm cell and traverse route is same; the affect range of banding echo wind is at the forefront of the band echo; strong wind area of floccus echo is around the storm monomer. The area of three types is mostly same both the identified wind range and the real wind, the hit rate of massive, banding echo and floccus echo is respectively 96.2%, 68.6% and 45.3%, floccus is lower because of the weak echo intensity and lower VIL. (4) Application the system of automatic identification system, the history course of thunderstorm wind in Henan province is anti-pushed. The results between calculate data and ground truth are consistent. This also proved that the automatic identification method is efficiently and feasible, it has important practical guiding significance for business system in short-term forecasting and nowcast warning. The work also provides a foundation in warning the position of surface gale.