###
气象:2010,36(1):54-58
本文二维码信息
码上扫一扫!
临近预报系统(SWIFT)中风暴产品的设计及应用
(1.广州中心气象台,广州 510080;2. 国家气象中心, 北京 100081;3.国家气象中心, 北京 100081;4.广东省湛江市气象局, 湛江 524001)
Storm Series Algorithms in the SWIFT and Application in the Second FDP Trial
(1.Guangzhou Central Meteorological Observatory, Guangzhou 510080;2. National Meteorological Center, Beijing 100081;3.National Meteorological Center, Beijing 100081;4.Zhanjiang Meteorological Bureau of Guangdong Province, Zhanjiang 524001)
摘要
图/表
参考文献
相似文献
本文已被:浏览 1848次   下载 2125
投稿时间:2008-06-11    修订日期:2009-09-14
中文摘要: 介绍了临近预报系统“SWIFT”(Severe Weather Integrated Forecasting Tools )中的风暴产品的设计,包括风暴识别、风暴追踪和风暴预报。在识别风暴时,采用了多反 射率因子阈值、特征核抽取和相近单体处理技术,并保留远距离上的强的2D风暴,该方法在 面对成串或成簇多单体时,能够分离多个单体核,并准确定位。在风暴追踪和预报算法中, 对当前时刻识别出来的风暴,利用匹配方案,将其与前1时刻的风暴建立对应关系,追寻历 史轨迹,匹配方案是在空间位置相关的前提下,按照相似原则进行;风暴预报采用TREC (Tr acking Radar Echoes by Correlation)技术获取的移动矢量场进行外推,提供未来1小时 内的风暴移动位置。在北京奥运会天气预报示范项目(Forecast Demonstration Project, 简称FDP)第二次 测试期间,该风暴产品得到应用。分析表明:在预报时效为30分钟时,风暴产品在X轴和Y 轴上的平均绝 对误差为7.1和6.2 km,样本数为3891个;随着预报时效的增加,风暴产品的平均绝对误差 增大,且在经向上的误差略大于纬向上;在径向上,风暴产品的预报出现了系统性的偏慢, 而在纬向上,预报出现了系统性的偏快。
Abstract:The storm series algorithms in the SWIFT (Severe Weather Integrated Forecastin g Tools), including storm cell identification, storm tracking and storm forecast , are discussed. Storm cell identification algorithm tests the intensity and con tinuity of the objective echoes by multiple prescribed thresholds to build 3 D storms. It uses multiple reflectivity thresholds, newly designs the techniques of cell nucleus extraction and close spaced storms processing, and therefore is capable of identifying embedded cells in multi cellular storms. The strong area components at a long distance are saved as 2 D storms. Storm cells identified in two consecutive volume scans are associated temporally to determine the cell tracking. The distance between the centroid of each cell detected in the current volume scan and each of the first guess location is calculated to check distanc e correlation. Those similar storms with distance correlation are matched. The m otion vector for each storm is computed by using the technique of TREC (Tracking Radar Echoes by Correlation), and storm locations in the next hour are provided . During the second trial of the FDP (Forecast Demonstration Project) in 2007, t hese algorithms have been applied. It is found that 3891 storms are identified a nd the mean absolute errors in the X-axis and Y-axis for 30 min storm fore cast are 7.1 and 6.2 km respectively. With the increase of forecast time length, the mean absolute errors of the storm product become larger, and the X-axis error is greater than that in the Y-axis. The statistical analysis also shows t hat the mean forecast velocity in the X-axis is less than the mean actual veloc ity of storms, but the conclusion is contrary in the Y-axis.
文章编号:     中图分类号:    文献标志码:
基金项目:中国气象局气象新技术推广项目预报员专项(CMATG2009YB09)和广东省气象局气象科技项 目(2007E08)联合资助
引用文本:
胡胜,罗兵,黄晓梅,梁巧倩,沃伟峰,2010.临近预报系统(SWIFT)中风暴产品的设计及应用[J].气象,36(1):54-58.
HU Sheng,LUO Bing,HUANG Xiaomei,LIANG Qiaoqian,WO Weifeng,2010.Storm Series Algorithms in the SWIFT and Application in the Second FDP Trial[J].Meteor Mon,36(1):54-58.